644 files changed, 8992 insertions, 6166 deletions

diff --git a/Source/CMakeLists.txt b/Source/CMakeLists.txt
index 1b6bb00..310ffeb 100644
--- a/Source/CMakeLists.txt
+++ b/Source/CMakeLists.txt
@@ -182,6 +182,8 @@ set(SRCS
   cmCheckCustomOutputs.cxx
   cmCLocaleEnvironmentScope.h
   cmCLocaleEnvironmentScope.cxx
+  cmCMakePath.h
+  cmCMakePath.cxx
   cmCommandArgumentParserHelper.cxx
   cmCommonTargetGenerator.cxx
   cmCommonTargetGenerator.h
@@ -412,6 +414,8 @@ set(SRCS
   cmSourceFileLocationKind.h
   cmSourceGroup.cxx
   cmSourceGroup.h
+  cmStandardLevelResolver.cxx
+  cmStandardLevelResolver.h
   cmState.cxx
   cmState.h
   cmStateDirectory.cxx
@@ -496,6 +500,8 @@ set(SRCS
   cmCMakeLanguageCommand.h
   cmCMakeMinimumRequired.cxx
   cmCMakeMinimumRequired.h
+  cmCMakePathCommand.h
+  cmCMakePathCommand.cxx
   cmCMakePolicyCommand.cxx
   cmCMakePolicyCommand.h
   cmConditionEvaluator.cxx
diff --git a/Source/CMakeVersion.cmake b/Source/CMakeVersion.cmake
index 5da59d4..835b785 100644
--- a/Source/CMakeVersion.cmake
+++ b/Source/CMakeVersion.cmake
@@ -1,7 +1,7 @@
 # CMake version number components.
 set(CMake_VERSION_MAJOR 3)
 set(CMake_VERSION_MINOR 18)
-set(CMake_VERSION_PATCH 2)
+set(CMake_VERSION_PATCH 20200910)
 #set(CMake_VERSION_RC 0)
 set(CMake_VERSION_IS_DIRTY 0)
 
diff --git a/Source/CPack/IFW/cmCPackIFWCommon.h b/Source/CPack/IFW/cmCPackIFWCommon.h
index 354d849..95ed213 100644
--- a/Source/CPack/IFW/cmCPackIFWCommon.h
+++ b/Source/CPack/IFW/cmCPackIFWCommon.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackIFWCommon_h
-#define cmCPackIFWCommon_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -77,5 +76,3 @@ protected:
                              cmCPackLog_msg.str().c_str());                   \
     }                                                                         \
   } while (false)
-
-#endif // cmCPackIFWCommon_h
diff --git a/Source/CPack/IFW/cmCPackIFWGenerator.h b/Source/CPack/IFW/cmCPackIFWGenerator.h
index 86a73c8..024d25d 100644
--- a/Source/CPack/IFW/cmCPackIFWGenerator.h
+++ b/Source/CPack/IFW/cmCPackIFWGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackIFWGenerator_h
-#define cmCPackIFWGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -152,5 +151,3 @@ private:
   std::vector<std::string> PkgsDirsVector;
   std::vector<std::string> RepoDirsVector;
 };
-
-#endif
diff --git a/Source/CPack/IFW/cmCPackIFWInstaller.h b/Source/CPack/IFW/cmCPackIFWInstaller.h
index 8b3f96a..6f398e3 100644
--- a/Source/CPack/IFW/cmCPackIFWInstaller.h
+++ b/Source/CPack/IFW/cmCPackIFWInstaller.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackIFWInstaller_h
-#define cmCPackIFWInstaller_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -132,5 +131,3 @@ protected:
   void printSkippedOptionWarning(const std::string& optionName,
                                  const std::string& optionValue);
 };
-
-#endif // cmCPackIFWInstaller_h
diff --git a/Source/CPack/IFW/cmCPackIFWPackage.h b/Source/CPack/IFW/cmCPackIFWPackage.h
index 6a4a170..dbd5540 100644
--- a/Source/CPack/IFW/cmCPackIFWPackage.h
+++ b/Source/CPack/IFW/cmCPackIFWPackage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackIFWPackage_h
-#define cmCPackIFWPackage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -149,5 +148,3 @@ public:
   // Patch to package directory
   std::string Directory;
 };
-
-#endif // cmCPackIFWPackage_h
diff --git a/Source/CPack/IFW/cmCPackIFWRepository.h b/Source/CPack/IFW/cmCPackIFWRepository.h
index c293981..21afd8b 100644
--- a/Source/CPack/IFW/cmCPackIFWRepository.h
+++ b/Source/CPack/IFW/cmCPackIFWRepository.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackIFWRepository_h
-#define cmCPackIFWRepository_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -84,5 +83,3 @@ public:
   RepositoriesVector RepositoryUpdate;
   std::string Directory;
 };
-
-#endif // cmCPackIFWRepository_h
diff --git a/Source/CPack/WiX/cmCMakeToWixPath.h b/Source/CPack/WiX/cmCMakeToWixPath.h
index 8bb9e04..074cc8e 100644
--- a/Source/CPack/WiX/cmCMakeToWixPath.h
+++ b/Source/CPack/WiX/cmCMakeToWixPath.h
@@ -1,12 +1,9 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCMakeToWixPath_h
-#define cmCMakeToWixPath_h
+#pragma once
 
 #include "cmConfigure.h" //IWYU pragma: keep
 
 #include <string>
 
 std::string CMakeToWixPath(const std::string& cygpath);
-
-#endif // cmCMakeToWixPath_h
diff --git a/Source/CPack/WiX/cmCPackWIXGenerator.cxx b/Source/CPack/WiX/cmCPackWIXGenerator.cxx
index 72af10b..8b3644f 100644
--- a/Source/CPack/WiX/cmCPackWIXGenerator.cxx
+++ b/Source/CPack/WiX/cmCPackWIXGenerator.cxx
@@ -221,6 +221,7 @@ bool cmCPackWIXGenerator::InitializeWiXConfiguration()
   this->LightExtensions.insert("WixUIExtension");
   CollectExtensions("CPACK_WIX_EXTENSIONS", this->LightExtensions);
   CollectExtensions("CPACK_WIX_LIGHT_EXTENSIONS", this->LightExtensions);
+  CollectXmlNamespaces("CPACK_WIX_CUSTOM_XMLNS", this->CustomXmlNamespaces);
 
   const char* patchFilePath = GetOption("CPACK_WIX_PATCH_FILE");
   if (patchFilePath) {
@@ -322,6 +323,7 @@ void cmCPackWIXGenerator::CreateWiXVariablesIncludeFile()
   cmWIXSourceWriter includeFile(this->Logger, includeFilename,
                                 this->ComponentGuidType,
                                 cmWIXSourceWriter::INCLUDE_ELEMENT_ROOT);
+  InjectXmlNamespaces(includeFile);
 
   CopyDefinition(includeFile, "CPACK_WIX_PRODUCT_GUID");
   CopyDefinition(includeFile, "CPACK_WIX_UPGRADE_GUID");
@@ -345,6 +347,7 @@ void cmCPackWIXGenerator::CreateWiXPropertiesIncludeFile()
   cmWIXSourceWriter includeFile(this->Logger, includeFilename,
                                 this->ComponentGuidType,
                                 cmWIXSourceWriter::INCLUDE_ELEMENT_ROOT);
+  InjectXmlNamespaces(includeFile);
 
   std::string prefix = "CPACK_WIX_PROPERTY_";
   std::vector<std::string> options = GetOptions();
@@ -393,6 +396,7 @@ void cmCPackWIXGenerator::CreateWiXProductFragmentIncludeFile()
   cmWIXSourceWriter includeFile(this->Logger, includeFilename,
                                 this->ComponentGuidType,
                                 cmWIXSourceWriter::INCLUDE_ELEMENT_ROOT);
+  InjectXmlNamespaces(includeFile);
 
   this->Patch->ApplyFragment("#PRODUCT", includeFile);
 }
@@ -432,6 +436,7 @@ bool cmCPackWIXGenerator::CreateWiXSourceFiles()
 
   cmWIXDirectoriesSourceWriter directoryDefinitions(
     this->Logger, directoryDefinitionsFilename, this->ComponentGuidType);
+  InjectXmlNamespaces(directoryDefinitions);
   directoryDefinitions.BeginElement("Fragment");
 
   std::string installRoot;
@@ -453,6 +458,7 @@ bool cmCPackWIXGenerator::CreateWiXSourceFiles()
 
   cmWIXFilesSourceWriter fileDefinitions(this->Logger, fileDefinitionsFilename,
                                          this->ComponentGuidType);
+  InjectXmlNamespaces(fileDefinitions);
 
   fileDefinitions.BeginElement("Fragment");
 
@@ -463,6 +469,7 @@ bool cmCPackWIXGenerator::CreateWiXSourceFiles()
 
   cmWIXFeaturesSourceWriter featureDefinitions(
     this->Logger, featureDefinitionsFilename, this->ComponentGuidType);
+  InjectXmlNamespaces(featureDefinitions);
 
   featureDefinitions.BeginElement("Fragment");
 
@@ -1147,6 +1154,35 @@ void cmCPackWIXGenerator::CollectExtensions(std::string const& variableName,
   extensions.insert(list.begin(), list.end());
 }
 
+void cmCPackWIXGenerator::CollectXmlNamespaces(std::string const& variableName,
+                                               xmlns_map_t& namespaces)
+{
+  const char* variableContent = GetOption(variableName.c_str());
+  if (!variableContent) {
+    return;
+  }
+
+  std::vector<std::string> list = cmExpandedList(variableContent);
+  for (std::string const& str : list) {
+    auto pos = str.find('=');
+    if (pos != std::string::npos) {
+      auto name = str.substr(0, pos);
+      auto value = str.substr(pos + 1);
+      namespaces.emplace(std::make_pair(name, value));
+    } else {
+      cmCPackLogger(cmCPackLog::LOG_ERROR,
+                    "Invalid element in CPACK_WIX_CUSTOM_XMLNS ignored: "
+                      << "\"" << str << "\"" << std::endl);
+    }
+  }
+  std::ostringstream oss;
+  for (auto& ns : namespaces) {
+    oss << " xmlns:" << ns.first << "=\""
+        << cmWIXSourceWriter::EscapeAttributeValue(ns.second) << '"';
+  }
+  SetOption("CPACK_WIX_CUSTOM_XMLNS_EXPANDED", oss.str().c_str());
+}
+
 void cmCPackWIXGenerator::AddCustomFlags(std::string const& variableName,
                                          std::ostream& stream)
 {
@@ -1172,3 +1208,10 @@ std::string cmCPackWIXGenerator::RelativePathWithoutComponentPrefix(
 
   return path.substr(pos + 1);
 }
+
+void cmCPackWIXGenerator::InjectXmlNamespaces(cmWIXSourceWriter& sourceWriter)
+{
+  for (auto& ns : this->CustomXmlNamespaces) {
+    sourceWriter.AddAttributeUnlessEmpty("xmlns:" + ns.first, ns.second);
+  }
+}
diff --git a/Source/CPack/WiX/cmCPackWIXGenerator.h b/Source/CPack/WiX/cmCPackWIXGenerator.h
index d5a16ec..8609cf3 100644
--- a/Source/CPack/WiX/cmCPackWIXGenerator.h
+++ b/Source/CPack/WiX/cmCPackWIXGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackWIXGenerator_h
-#define cmCPackWIXGenerator_h
+#pragma once
 
 #include <map>
 #include <memory>
@@ -49,6 +48,7 @@ private:
   using id_map_t = std::map<std::string, std::string>;
   using ambiguity_map_t = std::map<std::string, size_t>;
   using extension_set_t = std::set<std::string>;
+  using xmlns_map_t = std::map<std::string, std::string>;
 
   enum class DefinitionType
   {
@@ -147,16 +147,22 @@ private:
   void CollectExtensions(std::string const& variableName,
                          extension_set_t& extensions);
 
+  void CollectXmlNamespaces(std::string const& variableName,
+                            xmlns_map_t& namespaces);
+
   void AddCustomFlags(std::string const& variableName, std::ostream& stream);
 
   std::string RelativePathWithoutComponentPrefix(std::string const& path);
 
+  void InjectXmlNamespaces(cmWIXSourceWriter& sourceWriter);
+
   std::vector<std::string> WixSources;
   id_map_t PathToIdMap;
   ambiguity_map_t IdAmbiguityCounter;
 
   extension_set_t CandleExtensions;
   extension_set_t LightExtensions;
+  xmlns_map_t CustomXmlNamespaces;
 
   std::string CPackTopLevel;
 
@@ -164,5 +170,3 @@ private:
 
   cmWIXSourceWriter::GuidType ComponentGuidType;
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXAccessControlList.h b/Source/CPack/WiX/cmWIXAccessControlList.h
index 64f9a13..ee5efa5 100644
--- a/Source/CPack/WiX/cmWIXAccessControlList.h
+++ b/Source/CPack/WiX/cmWIXAccessControlList.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXAccessControlList_h
-#define cmWIXAccessControlList_h
+#pragma once
 
 #include "cmCPackLog.h"
 #include "cmInstalledFile.h"
@@ -29,5 +28,3 @@ private:
   cmInstalledFile const& InstalledFile;
   cmWIXSourceWriter& SourceWriter;
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXDirectoriesSourceWriter.h b/Source/CPack/WiX/cmWIXDirectoriesSourceWriter.h
index a907d6d..0af3094 100644
--- a/Source/CPack/WiX/cmWIXDirectoriesSourceWriter.h
+++ b/Source/CPack/WiX/cmWIXDirectoriesSourceWriter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXDirectoriesSourceWriter_h
-#define cmWIXDirectoriesSourceWriter_h
+#pragma once
 
 #include <string>
 
@@ -29,5 +28,3 @@ public:
 
   void EndInstallationPrefixDirectory(size_t size);
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXFeaturesSourceWriter.h b/Source/CPack/WiX/cmWIXFeaturesSourceWriter.h
index e03e87b..0facf97 100644
--- a/Source/CPack/WiX/cmWIXFeaturesSourceWriter.h
+++ b/Source/CPack/WiX/cmWIXFeaturesSourceWriter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXFeaturesSourceWriter_h
-#define cmWIXFeaturesSourceWriter_h
+#pragma once
 
 #include "cmCPackGenerator.h"
 #include "cmWIXPatch.h"
@@ -27,5 +26,3 @@ public:
 
   void EmitComponentRef(std::string const& id);
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXFilesSourceWriter.h b/Source/CPack/WiX/cmWIXFilesSourceWriter.h
index 8cc98f5..60dddd4 100644
--- a/Source/CPack/WiX/cmWIXFilesSourceWriter.h
+++ b/Source/CPack/WiX/cmWIXFilesSourceWriter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXFilesSourceWriter_h
-#define cmWIXFilesSourceWriter_h
+#pragma once
 
 #include "cmCPackGenerator.h"
 #include "cmWIXPatch.h"
@@ -37,5 +36,3 @@ public:
                                 std::string const& filePath, cmWIXPatch& patch,
                                 cmInstalledFile const* installedFile);
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXPatch.h b/Source/CPack/WiX/cmWIXPatch.h
index 31a60f4..c78722d 100644
--- a/Source/CPack/WiX/cmWIXPatch.h
+++ b/Source/CPack/WiX/cmWIXPatch.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXPatch_h
-#define cmWIXPatch_h
+#pragma once
 
 #include <string>
 
@@ -33,5 +32,3 @@ private:
 
   cmWIXPatchParser::fragment_map_t Fragments;
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXPatchParser.h b/Source/CPack/WiX/cmWIXPatchParser.h
index 8d5d2ad..70a21bc 100644
--- a/Source/CPack/WiX/cmWIXPatchParser.h
+++ b/Source/CPack/WiX/cmWIXPatchParser.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackWIXPatchParser_h
-#define cmCPackWIXPatchParser_h
+#pragma once
 
 #include <map>
 #include <memory>
@@ -91,5 +90,3 @@ private:
 
   std::vector<cmWIXPatchElement*> ElementStack;
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXRichTextFormatWriter.h b/Source/CPack/WiX/cmWIXRichTextFormatWriter.h
index a879f3d..99471f1 100644
--- a/Source/CPack/WiX/cmWIXRichTextFormatWriter.h
+++ b/Source/CPack/WiX/cmWIXRichTextFormatWriter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXRichTextFormatWriter_h
-#define cmWIXRichTextFormatWriter_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -42,5 +41,3 @@ private:
 
   cmsys::ofstream File;
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXShortcut.h b/Source/CPack/WiX/cmWIXShortcut.h
index c67baf3..315b5ea 100644
--- a/Source/CPack/WiX/cmWIXShortcut.h
+++ b/Source/CPack/WiX/cmWIXShortcut.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXShortcut_h
-#define cmWIXShortcut_h
+#pragma once
 
 #include <map>
 #include <set>
@@ -56,5 +55,3 @@ private:
   shortcut_type_map_t Shortcuts;
   shortcut_id_map_t EmptyIdMap;
 };
-
-#endif
diff --git a/Source/CPack/WiX/cmWIXSourceWriter.h b/Source/CPack/WiX/cmWIXSourceWriter.h
index 8cc2070..f643acd 100644
--- a/Source/CPack/WiX/cmWIXSourceWriter.h
+++ b/Source/CPack/WiX/cmWIXSourceWriter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmWIXSourceWriter_h
-#define cmWIXSourceWriter_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -50,6 +49,8 @@ public:
 
   std::string CreateGuidFromComponentId(std::string const& componentId);
 
+  static std::string EscapeAttributeValue(std::string const& value);
+
 protected:
   cmCPackLog* Logger;
 
@@ -64,8 +65,6 @@ private:
 
   void Indent(size_t count);
 
-  static std::string EscapeAttributeValue(std::string const& value);
-
   cmsys::ofstream File;
 
   State State;
@@ -76,5 +75,3 @@ private:
 
   GuidType ComponentGuidType;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackArchiveGenerator.h b/Source/CPack/cmCPackArchiveGenerator.h
index 7eb5665..5b40013 100644
--- a/Source/CPack/cmCPackArchiveGenerator.h
+++ b/Source/CPack/cmCPackArchiveGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackArchiveGenerator_h
-#define cmCPackArchiveGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -93,5 +92,3 @@ private:
   std::string ArchiveFormat;
   std::string OutputExtension;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackBundleGenerator.h b/Source/CPack/cmCPackBundleGenerator.h
index 27bac3a..072d14f 100644
--- a/Source/CPack/cmCPackBundleGenerator.h
+++ b/Source/CPack/cmCPackBundleGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackBundleGenerator_h
-#define cmCPackBundleGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -33,5 +32,3 @@ protected:
 
   std::string InstallPrefix;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackComponentGroup.h b/Source/CPack/cmCPackComponentGroup.h
index bb980d7..58377d4 100644
--- a/Source/CPack/cmCPackComponentGroup.h
+++ b/Source/CPack/cmCPackComponentGroup.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackComponentGroup_h
-#define cmCPackComponentGroup_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -167,5 +166,3 @@ public:
   /// The list of components.
   std::vector<cmCPackComponent*> Components;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackCygwinBinaryGenerator.h b/Source/CPack/cmCPackCygwinBinaryGenerator.h
index 47bd41e..f5f7700 100644
--- a/Source/CPack/cmCPackCygwinBinaryGenerator.h
+++ b/Source/CPack/cmCPackCygwinBinaryGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackCygwinBinaryGenerator_h
-#define cmCPackCygwinBinaryGenerator_h
+#pragma once
 
 #include "cmCPackArchiveGenerator.h"
 
@@ -25,5 +24,3 @@ protected:
   virtual const char* GetOutputExtension();
   std::string OutputExtension;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackCygwinSourceGenerator.h b/Source/CPack/cmCPackCygwinSourceGenerator.h
index 98d8f0a..964a4d4 100644
--- a/Source/CPack/cmCPackCygwinSourceGenerator.h
+++ b/Source/CPack/cmCPackCygwinSourceGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackCygwinSourceGenerator_h
-#define cmCPackCygwinSourceGenerator_h
+#pragma once
 
 #include "cmCPackArchiveGenerator.h"
 
@@ -27,5 +26,3 @@ protected:
   std::string InstallPrefix;
   std::string OutputExtension;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackDebGenerator.cxx b/Source/CPack/cmCPackDebGenerator.cxx
index 3d5fe6b..560e5c1 100644
--- a/Source/CPack/cmCPackDebGenerator.cxx
+++ b/Source/CPack/cmCPackDebGenerator.cxx
@@ -696,57 +696,57 @@ int cmCPackDebGenerator::createDeb()
 
   const char* debian_pkg_source =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_SOURCE");
-  if (debian_pkg_source && *debian_pkg_source) {
+  if (cmNonempty(debian_pkg_source)) {
     controlValues["Source"] = debian_pkg_source;
   }
   const char* debian_pkg_dep =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_DEPENDS");
-  if (debian_pkg_dep && *debian_pkg_dep) {
+  if (cmNonempty(debian_pkg_dep)) {
     controlValues["Depends"] = debian_pkg_dep;
   }
   const char* debian_pkg_rec =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_RECOMMENDS");
-  if (debian_pkg_rec && *debian_pkg_rec) {
+  if (cmNonempty(debian_pkg_rec)) {
     controlValues["Recommends"] = debian_pkg_rec;
   }
   const char* debian_pkg_sug =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_SUGGESTS");
-  if (debian_pkg_sug && *debian_pkg_sug) {
+  if (cmNonempty(debian_pkg_sug)) {
     controlValues["Suggests"] = debian_pkg_sug;
   }
   const char* debian_pkg_url =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_HOMEPAGE");
-  if (debian_pkg_url && *debian_pkg_url) {
+  if (cmNonempty(debian_pkg_url)) {
     controlValues["Homepage"] = debian_pkg_url;
   }
   const char* debian_pkg_predep =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_PREDEPENDS");
-  if (debian_pkg_predep && *debian_pkg_predep) {
+  if (cmNonempty(debian_pkg_predep)) {
     controlValues["Pre-Depends"] = debian_pkg_predep;
   }
   const char* debian_pkg_enhances =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_ENHANCES");
-  if (debian_pkg_enhances && *debian_pkg_enhances) {
+  if (cmNonempty(debian_pkg_enhances)) {
     controlValues["Enhances"] = debian_pkg_enhances;
   }
   const char* debian_pkg_breaks =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_BREAKS");
-  if (debian_pkg_breaks && *debian_pkg_breaks) {
+  if (cmNonempty(debian_pkg_breaks)) {
     controlValues["Breaks"] = debian_pkg_breaks;
   }
   const char* debian_pkg_conflicts =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_CONFLICTS");
-  if (debian_pkg_conflicts && *debian_pkg_conflicts) {
+  if (cmNonempty(debian_pkg_conflicts)) {
     controlValues["Conflicts"] = debian_pkg_conflicts;
   }
   const char* debian_pkg_provides =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_PROVIDES");
-  if (debian_pkg_provides && *debian_pkg_provides) {
+  if (cmNonempty(debian_pkg_provides)) {
     controlValues["Provides"] = debian_pkg_provides;
   }
   const char* debian_pkg_replaces =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_REPLACES");
-  if (debian_pkg_replaces && *debian_pkg_replaces) {
+  if (cmNonempty(debian_pkg_replaces)) {
     controlValues["Replaces"] = debian_pkg_replaces;
   }
 
@@ -756,7 +756,7 @@ int cmCPackDebGenerator::createDeb()
   const char* debian_pkg_shlibs =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_SHLIBS");
   const bool gen_shibs = this->IsOn("CPACK_DEBIAN_PACKAGE_GENERATE_SHLIBS") &&
-    debian_pkg_shlibs && *debian_pkg_shlibs;
+    cmNonempty(debian_pkg_shlibs);
   if (gen_shibs) {
     cmGeneratedFileStream out;
     out.Open(shlibsfilename, false, true);
@@ -832,11 +832,11 @@ int cmCPackDebGenerator::createDbgsymDDeb()
 
   const char* debian_pkg_source =
     this->GetOption("GEN_CPACK_DEBIAN_PACKAGE_SOURCE");
-  if (debian_pkg_source && *debian_pkg_source) {
+  if (cmNonempty(debian_pkg_source)) {
     controlValues["Source"] = debian_pkg_source;
   }
   const char* debian_build_ids = this->GetOption("GEN_BUILD_IDS");
-  if (debian_build_ids && *debian_build_ids) {
+  if (cmNonempty(debian_build_ids)) {
     controlValues["Build-Ids"] = debian_build_ids;
   }
 
diff --git a/Source/CPack/cmCPackDebGenerator.h b/Source/CPack/cmCPackDebGenerator.h
index ce77e08..ee8f39a 100644
--- a/Source/CPack/cmCPackDebGenerator.h
+++ b/Source/CPack/cmCPackDebGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackDebGenerator_h
-#define cmCPackDebGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -69,5 +68,3 @@ private:
 
   std::vector<std::string> packageFiles;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackDragNDropGenerator.cxx b/Source/CPack/cmCPackDragNDropGenerator.cxx
index fe7abf4..cefb906 100644
--- a/Source/CPack/cmCPackDragNDropGenerator.cxx
+++ b/Source/CPack/cmCPackDragNDropGenerator.cxx
@@ -8,7 +8,9 @@
 #include <map>
 
 #include <CoreFoundation/CoreFoundation.h>
+#include <cm3p/kwiml/abi.h>
 
+#include "cmsys/Base64.h"
 #include "cmsys/FStream.hxx"
 #include "cmsys/RegularExpression.hxx"
 
@@ -18,6 +20,7 @@
 #include "cmGeneratedFileStream.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
+#include "cmXMLWriter.h"
 
 #ifdef HAVE_CoreServices
 // For the old LocaleStringToLangAndRegionCodes() function, to convert
@@ -26,36 +29,28 @@
 #  include <CoreServices/CoreServices.h>
 #endif
 
-static const char* SLAHeader =
-  "data 'LPic' (5000) {\n"
-  "    $\"0002 0011 0003 0001 0000 0000 0002 0000\"\n"
-  "    $\"0008 0003 0000 0001 0004 0000 0004 0005\"\n"
-  "    $\"0000 000E 0006 0001 0005 0007 0000 0007\"\n"
-  "    $\"0008 0000 0047 0009 0000 0034 000A 0001\"\n"
-  "    $\"0035 000B 0001 0020 000C 0000 0011 000D\"\n"
-  "    $\"0000 005B 0004 0000 0033 000F 0001 000C\"\n"
-  "    $\"0010 0000 000B 000E 0000\"\n"
-  "};\n"
-  "\n";
-
-static const char* SLASTREnglish =
-  "resource 'STR#' (5002, \"English\") {\n"
-  "    {\n"
-  "        \"English\",\n"
-  "        \"Agree\",\n"
-  "        \"Disagree\",\n"
-  "        \"Print\",\n"
-  "        \"Save...\",\n"
-  "        \"You agree to the License Agreement terms when you click \"\n"
-  "        \"the \\\"Agree\\\" button.\",\n"
-  "        \"Software License Agreement\",\n"
-  "        \"This text cannot be saved.  This disk may be full or locked, "
-  "or the \"\n"
-  "        \"file may be locked.\",\n"
-  "        \"Unable to print.  Make sure you have selected a printer.\"\n"
-  "    }\n"
-  "};\n"
-  "\n";
+static const uint16_t DefaultLpic[] = {
+  /* clang-format off */
+  0x0002, 0x0011, 0x0003, 0x0001, 0x0000, 0x0000, 0x0002, 0x0000,
+  0x0008, 0x0003, 0x0000, 0x0001, 0x0004, 0x0000, 0x0004, 0x0005,
+  0x0000, 0x000E, 0x0006, 0x0001, 0x0005, 0x0007, 0x0000, 0x0007,
+  0x0008, 0x0000, 0x0047, 0x0009, 0x0000, 0x0034, 0x000A, 0x0001,
+  0x0035, 0x000B, 0x0001, 0x0020, 0x000C, 0x0000, 0x0011, 0x000D,
+  0x0000, 0x005B, 0x0004, 0x0000, 0x0033, 0x000F, 0x0001, 0x000C,
+  0x0010, 0x0000, 0x000B, 0x000E, 0x0000
+  /* clang-format on */
+};
+
+static const std::vector<std::string> DefaultMenu = {
+  { "English", "Agree", "Disagree", "Print", "Save...",
+    // NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+    "You agree to the License Agreement terms when "
+    "you click the \"Agree\" button.",
+    "Software License Agreement",
+    "This text cannot be saved.  "
+    "This disk may be full or locked, or the file may be locked.",
+    "Unable to print.  Make sure you have selected a printer." }
+};
 
 cmCPackDragNDropGenerator::cmCPackDragNDropGenerator()
   : singleLicense(false)
@@ -523,22 +518,43 @@ int cmCPackDragNDropGenerator::CreateDMG(const std::string& src_dir,
     }
   }
 
+  // Create the final compressed read-only disk image ...
+  std::ostringstream final_image_command;
+  final_image_command << this->GetOption("CPACK_COMMAND_HDIUTIL");
+  final_image_command << " convert \"" << temp_image << "\"";
+  final_image_command << " -format ";
+  final_image_command << cpack_dmg_format;
+  final_image_command << " -imagekey";
+  final_image_command << " zlib-level=9";
+  final_image_command << " -o \"" << output_file << "\"";
+
+  std::string convert_error;
+
+  if (!this->RunCommand(final_image_command, &convert_error)) {
+    cmCPackLogger(cmCPackLog::LOG_ERROR,
+                  "Error compressing disk image." << std::endl
+                                                  << convert_error
+                                                  << std::endl);
+
+    return 0;
+  }
+
   if (!cpack_license_file.empty() || !slaDirectory.empty()) {
     // Use old hardcoded style if sla_dir is not set
     bool oldStyle = slaDirectory.empty();
-    std::string sla_r =
-      cmStrCat(this->GetOption("CPACK_TOPLEVEL_DIRECTORY"), "/sla.r");
+    std::string sla_xml =
+      cmStrCat(this->GetOption("CPACK_TOPLEVEL_DIRECTORY"), "/sla.xml");
 
     std::vector<std::string> languages;
     if (!oldStyle) {
       cmExpandList(cpack_dmg_languages, languages);
     }
 
-    cmGeneratedFileStream ofs(sla_r);
-    ofs << "#include <CoreServices/CoreServices.r>\n\n";
+    std::vector<uint16_t> header_data;
     if (oldStyle) {
-      ofs << SLAHeader;
-      ofs << "\n";
+      header_data = std::vector<uint16_t>(
+        DefaultLpic,
+        DefaultLpic + (sizeof(DefaultLpic) / sizeof(*DefaultLpic)));
     } else {
       /*
        * LPic Layout
@@ -558,8 +574,6 @@ int cmCPackDragNDropGenerator::CreateDMG(const std::string& src_dir,
        * }
        */
 
-      // Create vector first for readability, then iterate to write to ofs
-      std::vector<uint16_t> header_data;
       header_data.push_back(0);
       header_data.push_back(languages.size());
       for (size_t i = 0; i < languages.size(); ++i) {
@@ -596,52 +610,50 @@ int cmCPackDragNDropGenerator::CreateDMG(const std::string& src_dir,
         header_data.push_back(0);
 #endif
       }
-      ofs << "data 'LPic' (5000) {\n";
-      ofs << std::hex << std::uppercase << std::setfill('0');
-
-      for (size_t i = 0; i < header_data.size(); ++i) {
-        if (i % 8 == 0) {
-          ofs << "    $\"";
-        }
-
-        ofs << std::setw(4) << header_data[i];
+    }
 
-        if (i % 8 == 7 || i == header_data.size() - 1) {
-          ofs << "\"\n";
-        } else {
-          ofs << " ";
-        }
+    RezDoc rez;
+
+    {
+      RezDict lpic = { {}, 5000, {} };
+      lpic.Data.reserve(header_data.size() * sizeof(header_data[0]));
+      for (uint16_t x : header_data) {
+        // LPic header is big-endian.
+        char* d = reinterpret_cast<char*>(&x);
+#if KWIML_ABI_ENDIAN_ID == KWIML_ABI_ENDIAN_ID_LITTLE
+        lpic.Data.push_back(d[1]);
+        lpic.Data.push_back(d[0]);
+#else
+        lpic.Data.push_back(d[0]);
+        lpic.Data.push_back(d[1]);
+#endif
       }
-      ofs << "};\n\n";
-      // Reset ofs options
-      ofs << std::dec << std::nouppercase << std::setfill(' ');
+      rez.LPic.Entries.emplace_back(std::move(lpic));
     }
 
     bool have_write_license_error = false;
     std::string error;
 
     if (oldStyle) {
-      if (!this->WriteLicense(ofs, 0, "", cpack_license_file, &error)) {
+      if (!this->WriteLicense(rez, 0, "", cpack_license_file, &error)) {
         have_write_license_error = true;
       }
     } else {
       for (size_t i = 0; i < languages.size() && !have_write_license_error;
            ++i) {
         if (singleLicense) {
-          if (!this->WriteLicense(ofs, i + 5000, languages[i],
+          if (!this->WriteLicense(rez, i + 5000, languages[i],
                                   cpack_license_file, &error)) {
             have_write_license_error = true;
           }
         } else {
-          if (!this->WriteLicense(ofs, i + 5000, languages[i], "", &error)) {
+          if (!this->WriteLicense(rez, i + 5000, languages[i], "", &error)) {
             have_write_license_error = true;
           }
         }
       }
     }
 
-    ofs.Close();
-
     if (have_write_license_error) {
       cmCPackLogger(cmCPackLog::LOG_ERROR,
                     "Error writing license file to SLA." << std::endl
@@ -650,96 +662,27 @@ int cmCPackDragNDropGenerator::CreateDMG(const std::string& src_dir,
       return 0;
     }
 
-    if (temp_image_format != "UDZO") {
-      temp_image_format = "UDZO";
-      // convert to UDZO to enable unflatten/flatten
-      std::string temp_udzo = cmStrCat(
-        this->GetOption("CPACK_TOPLEVEL_DIRECTORY"), "/temp-udzo.dmg");
+    this->WriteRezXML(sla_xml, rez);
 
-      std::ostringstream udco_image_command;
-      udco_image_command << this->GetOption("CPACK_COMMAND_HDIUTIL");
-      udco_image_command << " convert \"" << temp_image << "\"";
-      udco_image_command << " -format UDZO";
-      udco_image_command << " -ov -o \"" << temp_udzo << "\"";
-
-      if (!this->RunCommand(udco_image_command, &error)) {
-        cmCPackLogger(cmCPackLog::LOG_ERROR,
-                      "Error converting to UDCO dmg for adding SLA."
-                        << std::endl
-                        << error << std::endl);
-        return 0;
-      }
-      temp_image = temp_udzo;
-    }
-
-    // unflatten dmg
-    std::ostringstream unflatten_command;
-    unflatten_command << this->GetOption("CPACK_COMMAND_HDIUTIL");
-    unflatten_command << " unflatten ";
-    unflatten_command << "\"" << temp_image << "\"";
-
-    if (!this->RunCommand(unflatten_command, &error)) {
-      cmCPackLogger(cmCPackLog::LOG_ERROR,
-                    "Error unflattening dmg for adding SLA." << std::endl
-                                                             << error
-                                                             << std::endl);
-      return 0;
-    }
-
-    // Rez the SLA
+    // Create the final compressed read-only disk image ...
     std::ostringstream embed_sla_command;
-    embed_sla_command << this->GetOption("CPACK_COMMAND_REZ");
-    const char* sysroot = this->GetOption("CPACK_OSX_SYSROOT");
-    if (sysroot && sysroot[0] != '\0') {
-      embed_sla_command << " -isysroot \"" << sysroot << "\"";
-    }
-    embed_sla_command << " \"" << sla_r << "\"";
-    embed_sla_command << " -a -o ";
-    embed_sla_command << "\"" << temp_image << "\"";
-
-    if (!this->RunCommand(embed_sla_command, &error)) {
+    embed_sla_command << this->GetOption("CPACK_COMMAND_HDIUTIL");
+    embed_sla_command << " udifrez";
+    embed_sla_command << " -xml";
+    embed_sla_command << " \"" << sla_xml << "\"";
+    embed_sla_command << " FIXME_WHY_IS_THIS_ARGUMENT_NEEDED";
+    embed_sla_command << " \"" << output_file << "\"";
+    std::string embed_error;
+    if (!this->RunCommand(embed_sla_command, &embed_error)) {
       cmCPackLogger(cmCPackLog::LOG_ERROR,
-                    "Error adding SLA." << std::endl
-                                        << error << std::endl);
-      return 0;
-    }
-
-    // flatten dmg
-    std::ostringstream flatten_command;
-    flatten_command << this->GetOption("CPACK_COMMAND_HDIUTIL");
-    flatten_command << " flatten ";
-    flatten_command << "\"" << temp_image << "\"";
+                    "Error compressing disk image." << std::endl
+                                                    << embed_error
+                                                    << std::endl);
 
-    if (!this->RunCommand(flatten_command, &error)) {
-      cmCPackLogger(cmCPackLog::LOG_ERROR,
-                    "Error flattening dmg for adding SLA." << std::endl
-                                                           << error
-                                                           << std::endl);
       return 0;
     }
   }
 
-  // Create the final compressed read-only disk image ...
-  std::ostringstream final_image_command;
-  final_image_command << this->GetOption("CPACK_COMMAND_HDIUTIL");
-  final_image_command << " convert \"" << temp_image << "\"";
-  final_image_command << " -format ";
-  final_image_command << cpack_dmg_format;
-  final_image_command << " -imagekey";
-  final_image_command << " zlib-level=9";
-  final_image_command << " -o \"" << output_file << "\"";
-
-  std::string convert_error;
-
-  if (!this->RunCommand(final_image_command, &convert_error)) {
-    cmCPackLogger(cmCPackLog::LOG_ERROR,
-                  "Error compressing disk image." << std::endl
-                                                  << convert_error
-                                                  << std::endl);
-
-    return 0;
-  }
-
   return 1;
 }
 
@@ -788,10 +731,67 @@ std::string cmCPackDragNDropGenerator::GetComponentInstallDirNameSuffix(
   return GetComponentPackageFileName(package_file_name, componentName, false);
 }
 
-bool cmCPackDragNDropGenerator::WriteLicense(
-  cmGeneratedFileStream& outputStream, int licenseNumber,
-  std::string licenseLanguage, const std::string& licenseFile,
-  std::string* error)
+void cmCPackDragNDropGenerator::WriteRezXML(std::string const& file,
+                                            RezDoc const& rez)
+{
+  cmGeneratedFileStream fxml(file);
+  cmXMLWriter xml(fxml);
+  xml.StartDocument();
+  xml.StartElement("plist");
+  xml.Attribute("version", "1.0");
+  xml.StartElement("dict");
+  this->WriteRezArray(xml, rez.LPic);
+  this->WriteRezArray(xml, rez.Menu);
+  this->WriteRezArray(xml, rez.Text);
+  this->WriteRezArray(xml, rez.RTF);
+  xml.EndElement(); // dict
+  xml.EndElement(); // plist
+  xml.EndDocument();
+  fxml.Close();
+}
+
+void cmCPackDragNDropGenerator::WriteRezArray(cmXMLWriter& xml,
+                                              RezArray const& array)
+{
+  if (array.Entries.empty()) {
+    return;
+  }
+  xml.StartElement("key");
+  xml.Content(array.Key);
+  xml.EndElement(); // key
+  xml.StartElement("array");
+  for (RezDict const& dict : array.Entries) {
+    this->WriteRezDict(xml, dict);
+  }
+  xml.EndElement(); // array
+}
+
+void cmCPackDragNDropGenerator::WriteRezDict(cmXMLWriter& xml,
+                                             RezDict const& dict)
+{
+  std::vector<char> base64buf(dict.Data.size() * 3 / 2 + 5);
+  size_t base64len =
+    cmsysBase64_Encode(dict.Data.data(), dict.Data.size(),
+                       reinterpret_cast<unsigned char*>(base64buf.data()), 0);
+  std::string base64data(base64buf.data(), base64len);
+  /* clang-format off */
+  xml.StartElement("dict");
+  xml.StartElement("key");    xml.Content("Attributes"); xml.EndElement();
+  xml.StartElement("string"); xml.Content("0x0000");     xml.EndElement();
+  xml.StartElement("key");    xml.Content("Data");       xml.EndElement();
+  xml.StartElement("data");   xml.Content(base64data);   xml.EndElement();
+  xml.StartElement("key");    xml.Content("ID");         xml.EndElement();
+  xml.StartElement("string"); xml.Content(dict.ID);      xml.EndElement();
+  xml.StartElement("key");    xml.Content("Name");       xml.EndElement();
+  xml.StartElement("string"); xml.Content(dict.Name);    xml.EndElement();
+  xml.EndElement(); // dict
+  /* clang-format on */
+}
+
+bool cmCPackDragNDropGenerator::WriteLicense(RezDoc& rez, size_t licenseNumber,
+                                             std::string licenseLanguage,
+                                             const std::string& licenseFile,
+                                             std::string* error)
 {
   if (!licenseFile.empty() && !singleLicense) {
     licenseNumber = 5002;
@@ -799,11 +799,11 @@ bool cmCPackDragNDropGenerator::WriteLicense(
   }
 
   // License file
-  std::string license_format = "TEXT";
+  RezArray* licenseArray = &rez.Text;
   std::string actual_license;
   if (!licenseFile.empty()) {
     if (cmHasLiteralSuffix(licenseFile, ".rtf")) {
-      license_format = "RTF ";
+      licenseArray = &rez.RTF;
     }
     actual_license = licenseFile;
   } else {
@@ -812,85 +812,86 @@ bool cmCPackDragNDropGenerator::WriteLicense(
     if (cmSystemTools::FileExists(license_wo_ext + ".txt")) {
       actual_license = license_wo_ext + ".txt";
     } else {
-      license_format = "RTF ";
+      licenseArray = &rez.RTF;
       actual_license = license_wo_ext + ".rtf";
     }
   }
 
-  // License header
-  outputStream << "data '" << license_format << "' (" << licenseNumber
-               << ", \"" << licenseLanguage << "\") {\n";
   // License body
-  cmsys::ifstream license_ifs;
-  license_ifs.open(actual_license.c_str());
-  if (license_ifs.is_open()) {
-    while (license_ifs.good()) {
-      std::string line;
-      std::getline(license_ifs, line);
-      if (!line.empty()) {
-        EscapeQuotesAndBackslashes(line);
-        std::vector<std::string> lines;
-        if (!this->BreakLongLine(line, lines, error)) {
-          return false;
-        }
-        for (auto const& l : lines) {
-          outputStream << "        \"" << l << "\"\n";
-        }
-      }
-      outputStream << "        \"\\n\"\n";
+  {
+    RezDict license = { licenseLanguage, licenseNumber, {} };
+    std::vector<std::string> lines;
+    if (!this->ReadFile(actual_license, lines, error)) {
+      return false;
     }
-    license_ifs.close();
+    this->EncodeLicense(license, lines);
+    licenseArray->Entries.emplace_back(std::move(license));
   }
 
-  // End of License
-  outputStream << "};\n\n";
-  if (!licenseFile.empty() && !singleLicense) {
-    outputStream << SLASTREnglish;
-  } else {
-    // Menu header
-    outputStream << "resource 'STR#' (" << licenseNumber << ", \""
-                 << licenseLanguage << "\") {\n";
-    outputStream << "    {\n";
-
-    // Menu body
-    cmsys::ifstream menu_ifs;
-    menu_ifs.open(
-      (slaDirectory + "/" + licenseLanguage + ".menu.txt").c_str());
-    if (menu_ifs.is_open()) {
-      size_t lines_written = 0;
-      while (menu_ifs.good()) {
-        // Lines written from original file, not from broken up lines
-        std::string line;
-        std::getline(menu_ifs, line);
-        if (!line.empty()) {
-          EscapeQuotesAndBackslashes(line);
-          std::vector<std::string> lines;
-          if (!this->BreakLongLine(line, lines, error)) {
-            return false;
-          }
-          for (size_t i = 0; i < lines.size(); ++i) {
-            std::string comma;
-            // We need a comma after every complete string,
-            // but not on the very last line
-            if (lines_written != 8 && i == lines.size() - 1) {
-              comma = ",";
-            } else {
-              comma = "";
-            }
-            outputStream << "        \"" << lines[i] << "\"" << comma << "\n";
-          }
-          ++lines_written;
-        }
+  // Menu body
+  {
+    RezDict menu = { licenseLanguage, licenseNumber, {} };
+    if (!licenseFile.empty() && !singleLicense) {
+      this->EncodeMenu(menu, DefaultMenu);
+    } else {
+      std::vector<std::string> lines;
+      std::string actual_menu =
+        slaDirectory + "/" + licenseLanguage + ".menu.txt";
+      if (!this->ReadFile(actual_menu, lines, error)) {
+        return false;
       }
-      menu_ifs.close();
+      this->EncodeMenu(menu, lines);
     }
+    rez.Menu.Entries.emplace_back(std::move(menu));
+  }
+
+  return true;
+}
+
+void cmCPackDragNDropGenerator::EncodeLicense(
+  RezDict& dict, std::vector<std::string> const& lines)
+{
+  // License text uses CR newlines.
+  for (std::string const& l : lines) {
+    dict.Data.insert(dict.Data.end(), l.begin(), l.end());
+    dict.Data.push_back('\r');
+  }
+  dict.Data.push_back('\r');
+}
 
-    // End of menu
-    outputStream << "    }\n";
-    outputStream << "};\n";
-    outputStream << "\n";
+void cmCPackDragNDropGenerator::EncodeMenu(
+  RezDict& dict, std::vector<std::string> const& lines)
+{
+  // Menu resources start with a big-endian uint16_t for number of lines:
+  {
+    uint16_t numLines = static_cast<uint16_t>(lines.size());
+    char* d = reinterpret_cast<char*>(&numLines);
+#if KWIML_ABI_ENDIAN_ID == KWIML_ABI_ENDIAN_ID_LITTLE
+    dict.Data.push_back(d[1]);
+    dict.Data.push_back(d[0]);
+#else
+    dict.Data.push_back(d[0]);
+    dict.Data.push_back(d[1]);
+#endif
   }
+  // Each line starts with a uint8_t length, plus the bytes themselves:
+  for (std::string const& l : lines) {
+    dict.Data.push_back(static_cast<unsigned char>(l.length()));
+    dict.Data.insert(dict.Data.end(), l.begin(), l.end());
+  }
+}
 
+bool cmCPackDragNDropGenerator::ReadFile(std::string const& file,
+                                         std::vector<std::string>& lines,
+                                         std::string* error)
+{
+  cmsys::ifstream ifs(file);
+  std::string line;
+  while (std::getline(ifs, line)) {
+    if (!this->BreakLongLine(line, lines, error)) {
+      return false;
+    }
+  }
   return true;
 }
 
@@ -898,7 +899,7 @@ bool cmCPackDragNDropGenerator::BreakLongLine(const std::string& line,
                                               std::vector<std::string>& lines,
                                               std::string* error)
 {
-  const size_t max_line_length = 512;
+  const size_t max_line_length = 255;
   size_t line_length = max_line_length;
   for (size_t i = 0; i < line.size(); i += line_length) {
     line_length = max_line_length;
@@ -913,25 +914,10 @@ bool cmCPackDragNDropGenerator::BreakLongLine(const std::string& line,
     if (line_length == 0) {
       *error = "Please make sure there are no words "
                "(or character sequences not broken up by spaces or newlines) "
-               "in your license file which are more than 512 characters long.";
+               "in your license file which are more than 255 characters long.";
       return false;
     }
     lines.push_back(line.substr(i, line_length));
   }
   return true;
 }
-
-void cmCPackDragNDropGenerator::EscapeQuotesAndBackslashes(std::string& line)
-{
-  std::string::size_type backslash_pos = line.find('\\');
-  while (backslash_pos != std::string::npos) {
-    line.replace(backslash_pos, 1, "\\\\");
-    backslash_pos = line.find('\\', backslash_pos + 2);
-  }
-
-  std::string::size_type quote_pos = line.find('\"');
-  while (quote_pos != std::string::npos) {
-    line.replace(quote_pos, 1, "\\\"");
-    quote_pos = line.find('\"', quote_pos + 2);
-  }
-}
diff --git a/Source/CPack/cmCPackDragNDropGenerator.h b/Source/CPack/cmCPackDragNDropGenerator.h
index f8c86c0..310b0ab 100644
--- a/Source/CPack/cmCPackDragNDropGenerator.h
+++ b/Source/CPack/cmCPackDragNDropGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackDragNDropGenerator_h
-#define cmCPackDragNDropGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -14,6 +13,7 @@
 #include "cmCPackGenerator.h"
 
 class cmGeneratedFileStream;
+class cmXMLWriter;
 
 /** \class cmCPackDragNDropGenerator
  * \brief A generator for OSX drag-n-drop installs
@@ -45,12 +45,38 @@ private:
   std::string slaDirectory;
   bool singleLicense;
 
-  bool WriteLicense(cmGeneratedFileStream& outputStream, int licenseNumber,
+  struct RezDict
+  {
+    std::string Name;
+    size_t ID;
+    std::vector<unsigned char> Data;
+  };
+
+  struct RezArray
+  {
+    std::string Key;
+    std::vector<RezDict> Entries;
+  };
+
+  struct RezDoc
+  {
+    RezArray LPic = { "LPic", {} };
+    RezArray Menu = { "STR#", {} };
+    RezArray Text = { "TEXT", {} };
+    RezArray RTF = { "RTF ", {} };
+  };
+
+  void WriteRezXML(std::string const& file, RezDoc const& rez);
+  void WriteRezArray(cmXMLWriter& xml, RezArray const& array);
+  void WriteRezDict(cmXMLWriter& xml, RezDict const& dict);
+
+  bool WriteLicense(RezDoc& rez, size_t licenseNumber,
                     std::string licenseLanguage,
                     const std::string& licenseFile, std::string* error);
+  void EncodeLicense(RezDict& dict, std::vector<std::string> const& lines);
+  void EncodeMenu(RezDict& dict, std::vector<std::string> const& lines);
+  bool ReadFile(std::string const& file, std::vector<std::string>& lines,
+                std::string* error);
   bool BreakLongLine(const std::string& line, std::vector<std::string>& lines,
                      std::string* error);
-  void EscapeQuotesAndBackslashes(std::string& line);
 };
-
-#endif
diff --git a/Source/CPack/cmCPackExternalGenerator.cxx b/Source/CPack/cmCPackExternalGenerator.cxx
index 11e1aec..0bc8456 100644
--- a/Source/CPack/cmCPackExternalGenerator.cxx
+++ b/Source/CPack/cmCPackExternalGenerator.cxx
@@ -61,7 +61,7 @@ int cmCPackExternalGenerator::PackageFiles()
   }
 
   const char* packageScript = this->GetOption("CPACK_EXTERNAL_PACKAGE_SCRIPT");
-  if (packageScript && *packageScript) {
+  if (cmNonempty(packageScript)) {
     if (!cmSystemTools::FileIsFullPath(packageScript)) {
       cmCPackLogger(
         cmCPackLog::LOG_ERROR,
@@ -75,6 +75,12 @@ int cmCPackExternalGenerator::PackageFiles()
     if (cmSystemTools::GetErrorOccuredFlag() || !res) {
       return 0;
     }
+
+    const char* builtPackagesStr =
+      this->GetOption("CPACK_EXTERNAL_BUILT_PACKAGES");
+    if (builtPackagesStr) {
+      cmExpandList(builtPackagesStr, this->packageFileNames, false);
+    }
   }
 
   return 1;
@@ -205,7 +211,7 @@ int cmCPackExternalGenerator::cmCPackExternalVersionGenerator::WriteToJSON(
 
   const char* defaultDirectoryPermissions =
     this->Parent->GetOption("CPACK_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS");
-  if (defaultDirectoryPermissions && *defaultDirectoryPermissions) {
+  if (cmNonempty(defaultDirectoryPermissions)) {
     root["defaultDirectoryPermissions"] = defaultDirectoryPermissions;
   }
   if (cmIsInternallyOn(this->Parent->GetOption("CPACK_SET_DESTDIR"))) {
diff --git a/Source/CPack/cmCPackExternalGenerator.h b/Source/CPack/cmCPackExternalGenerator.h
index 80011fd..dfd13e8 100644
--- a/Source/CPack/cmCPackExternalGenerator.h
+++ b/Source/CPack/cmCPackExternalGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackExternalGenerator_h
-#define cmCPackExternalGenerator_h
+#pragma once
 
 #include <memory>
 #include <string>
@@ -86,5 +85,3 @@ private:
 
   std::unique_ptr<cmCPackExternalVersionGenerator> Generator;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackFreeBSDGenerator.h b/Source/CPack/cmCPackFreeBSDGenerator.h
index a18b72f..eed8053 100644
--- a/Source/CPack/cmCPackFreeBSDGenerator.h
+++ b/Source/CPack/cmCPackFreeBSDGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackFreeBSDGenerator_h
-#define cmCPackFreeBSDGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -33,5 +32,3 @@ protected:
   std::string var_lookup(const char* var_name);
   void write_manifest_fields(cmGeneratedFileStream&);
 };
-
-#endif
diff --git a/Source/CPack/cmCPackGenerator.cxx b/Source/CPack/cmCPackGenerator.cxx
index 288dc58..a9fe91c 100644
--- a/Source/CPack/cmCPackGenerator.cxx
+++ b/Source/CPack/cmCPackGenerator.cxx
@@ -20,6 +20,7 @@
 #include "cmGeneratedFileStream.h"
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStateSnapshot.h"
 #include "cmStringAlgorithms.h"
@@ -216,7 +217,7 @@ int cmCPackGenerator::InstallProject()
   mode_t* default_dir_mode = nullptr;
   const char* default_dir_install_permissions =
     this->GetOption("CPACK_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS");
-  if (default_dir_install_permissions && *default_dir_install_permissions) {
+  if (cmNonempty(default_dir_install_permissions)) {
     std::vector<std::string> items =
       cmExpandedList(default_dir_install_permissions);
     for (const auto& arg : items) {
@@ -264,6 +265,23 @@ int cmCPackGenerator::InstallProject()
     return 0;
   }
 
+  // Run pre-build actions
+  const char* preBuildScripts = this->GetOption("CPACK_PRE_BUILD_SCRIPTS");
+  if (preBuildScripts) {
+    const auto scripts = cmExpandedList(preBuildScripts, false);
+    for (const auto& script : scripts) {
+      cmCPackLogger(cmCPackLog::LOG_OUTPUT,
+                    "Executing pre-build script: " << script << std::endl);
+
+      if (!this->MakefileMap->ReadListFile(script)) {
+        cmCPackLogger(cmCPackLog::LOG_ERROR,
+                      "The pre-build script not found: " << script
+                                                         << std::endl);
+        return 0;
+      }
+    }
+  }
+
   if (setDestDir) {
     cmSystemTools::PutEnv("DESTDIR=");
   }
@@ -276,7 +294,7 @@ int cmCPackGenerator::InstallProjectViaInstallCommands(
 {
   (void)setDestDir;
   const char* installCommands = this->GetOption("CPACK_INSTALL_COMMANDS");
-  if (installCommands && *installCommands) {
+  if (cmNonempty(installCommands)) {
     std::string tempInstallDirectoryEnv =
       cmStrCat("CMAKE_INSTALL_PREFIX=", tempInstallDirectory);
     cmSystemTools::PutEnv(tempInstallDirectoryEnv);
@@ -327,13 +345,14 @@ int cmCPackGenerator::InstallProjectViaInstalledDirectories(
   }
   const char* installDirectories =
     this->GetOption("CPACK_INSTALLED_DIRECTORIES");
-  if (installDirectories && *installDirectories) {
+  if (cmNonempty(installDirectories)) {
     std::vector<std::string> installDirectoriesVector =
       cmExpandedList(installDirectories);
     if (installDirectoriesVector.size() % 2 != 0) {
       cmCPackLogger(
         cmCPackLog::LOG_ERROR,
-        "CPACK_INSTALLED_DIRECTORIES should contain pairs of <directory> and "
+        "CPACK_INSTALLED_DIRECTORIES should contain pairs of <directory> "
+        "and "
         "<subdirectory>. The <subdirectory> can be '.' to be installed in "
         "the toplevel directory of installation."
           << std::endl);
@@ -475,10 +494,10 @@ int cmCPackGenerator::InstallProjectViaInstallScript(
                     "- Install script: " << installScript << std::endl);
 
       if (setDestDir) {
-        // For DESTDIR based packaging, use the *project* CMAKE_INSTALL_PREFIX
-        // underneath the tempInstallDirectory. The value of the project's
-        // CMAKE_INSTALL_PREFIX is sent in here as the value of the
-        // CPACK_INSTALL_PREFIX variable.
+        // For DESTDIR based packaging, use the *project*
+        // CMAKE_INSTALL_PREFIX underneath the tempInstallDirectory. The
+        // value of the project's CMAKE_INSTALL_PREFIX is sent in here as the
+        // value of the CPACK_INSTALL_PREFIX variable.
 
         std::string dir;
         if (this->GetOption("CPACK_INSTALL_PREFIX")) {
@@ -523,7 +542,7 @@ int cmCPackGenerator::InstallProjectViaInstallCMakeProjects(
   const char* cmakeProjects = this->GetOption("CPACK_INSTALL_CMAKE_PROJECTS");
   const char* cmakeGenerator = this->GetOption("CPACK_CMAKE_GENERATOR");
   std::string absoluteDestFiles;
-  if (cmakeProjects && *cmakeProjects) {
+  if (cmNonempty(cmakeProjects)) {
     if (!cmakeGenerator) {
       cmCPackLogger(cmCPackLog::LOG_ERROR,
                     "CPACK_INSTALL_CMAKE_PROJECTS is specified, but "
@@ -576,7 +595,7 @@ int cmCPackGenerator::InstallProjectViaInstallCMakeProjects(
         std::string installTypesVar = "CPACK_" +
           cmSystemTools::UpperCase(project.Component) + "_INSTALL_TYPES";
         const char* installTypes = this->GetOption(installTypesVar);
-        if (installTypes && *installTypes) {
+        if (cmNonempty(installTypes)) {
           std::vector<std::string> installTypesVector =
             cmExpandedList(installTypes);
           for (std::string const& installType : installTypesVector) {
@@ -589,7 +608,7 @@ int cmCPackGenerator::InstallProjectViaInstallCMakeProjects(
         std::string componentsVar =
           "CPACK_COMPONENTS_" + cmSystemTools::UpperCase(project.Component);
         const char* components = this->GetOption(componentsVar);
-        if (components && *components) {
+        if (cmNonempty(components)) {
           cmExpandList(components, componentsVector);
           for (std::string const& comp : componentsVector) {
             project.Components.push_back(
@@ -753,7 +772,7 @@ int cmCPackGenerator::InstallCMakeProject(
 
   const char* default_dir_inst_permissions =
     this->GetOption("CPACK_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS");
-  if (default_dir_inst_permissions && *default_dir_inst_permissions) {
+  if (cmNonempty(default_dir_inst_permissions)) {
     mf.AddDefinition("CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS",
                      default_dir_inst_permissions);
   }
@@ -811,7 +830,7 @@ int cmCPackGenerator::InstallCMakeProject(
      *     - Because it was already used for component install
      *       in order to put things in subdirs...
      */
-    cmSystemTools::PutEnv(std::string("DESTDIR=") + tempInstallDirectory);
+    cmSystemTools::PutEnv("DESTDIR=" + tempInstallDirectory);
     cmCPackLogger(cmCPackLog::LOG_DEBUG,
                   "- Creating directory: '" << dir << "'" << std::endl);
 
@@ -887,8 +906,8 @@ int cmCPackGenerator::InstallCMakeProject(
   // forward definition of CMAKE_ABSOLUTE_DESTINATION_FILES
   // to CPack (may be used by generators like CPack RPM or DEB)
   // in order to transparently handle ABSOLUTE PATH
-  if (const char* def = mf.GetDefinition("CMAKE_ABSOLUTE_DESTINATION_FILES")) {
-    mf.AddDefinition("CPACK_ABSOLUTE_DESTINATION_FILES", def);
+  if (cmProp def = mf.GetDefinition("CMAKE_ABSOLUTE_DESTINATION_FILES")) {
+    mf.AddDefinition("CPACK_ABSOLUTE_DESTINATION_FILES", *def);
   }
 
   // Now rebuild the list of files after installation
@@ -921,11 +940,11 @@ int cmCPackGenerator::InstallCMakeProject(
     }
   }
 
-  if (auto d = mf.GetDefinition("CPACK_ABSOLUTE_DESTINATION_FILES")) {
+  if (cmProp d = mf.GetDefinition("CPACK_ABSOLUTE_DESTINATION_FILES")) {
     if (!absoluteDestFiles.empty()) {
       absoluteDestFiles += ";";
     }
-    absoluteDestFiles += d;
+    absoluteDestFiles += *d;
     cmCPackLogger(cmCPackLog::LOG_DEBUG,
                   "Got some ABSOLUTE DESTINATION FILES: " << absoluteDestFiles
                                                           << std::endl);
@@ -936,12 +955,13 @@ int cmCPackGenerator::InstallCMakeProject(
         GetComponentInstallDirNameSuffix(component);
       if (nullptr != this->GetOption(absoluteDestFileComponent)) {
         std::string absoluteDestFilesListComponent =
-          cmStrCat(this->GetOption(absoluteDestFileComponent), ';', d);
+          cmStrCat(this->GetOption(absoluteDestFileComponent), ';', *d);
         this->SetOption(absoluteDestFileComponent,
                         absoluteDestFilesListComponent.c_str());
       } else {
-        this->SetOption(absoluteDestFileComponent,
-                        mf.GetDefinition("CPACK_ABSOLUTE_DESTINATION_FILES"));
+        this->SetOption(
+          absoluteDestFileComponent,
+          cmToCStr(mf.GetDefinition("CPACK_ABSOLUTE_DESTINATION_FILES")));
       }
     }
   }
@@ -964,8 +984,8 @@ bool cmCPackGenerator::ReadListFile(const char* moduleName)
 void cmCPackGenerator::SetOptionIfNotSet(const std::string& op,
                                          const char* value)
 {
-  const char* def = this->MakefileMap->GetDefinition(op);
-  if (def && *def) {
+  cmProp def = this->MakefileMap->GetDefinition(op);
+  if (cmNonempty(def)) {
     return;
   }
   this->SetOption(op, value);
@@ -1076,6 +1096,25 @@ int cmCPackGenerator::DoPackage()
       return 0;
     }
   }
+  // Run post-build actions
+  const char* postBuildScripts = this->GetOption("CPACK_POST_BUILD_SCRIPTS");
+  if (postBuildScripts) {
+    this->MakefileMap->AddDefinition("CPACK_PACKAGE_FILES",
+                                     cmJoin(this->packageFileNames, ";"));
+
+    const auto scripts = cmExpandedList(postBuildScripts, false);
+    for (const auto& script : scripts) {
+      cmCPackLogger(cmCPackLog::LOG_OUTPUT,
+                    "Executing post-build script: " << script << std::endl);
+
+      if (!this->MakefileMap->ReadListFile(script)) {
+        cmCPackLogger(cmCPackLog::LOG_ERROR,
+                      "The post-build script not found: " << script
+                                                          << std::endl);
+        return 0;
+      }
+    }
+  }
 
   /* Prepare checksum algorithm*/
   const char* algo = this->GetOption("CPACK_PACKAGE_CHECKSUM");
@@ -1177,30 +1216,31 @@ bool cmCPackGenerator::IsOn(const std::string& name) const
 
 bool cmCPackGenerator::IsSetToOff(const std::string& op) const
 {
-  const char* ret = this->MakefileMap->GetDefinition(op);
-  if (ret && *ret) {
-    return cmIsOff(ret);
+  cmProp ret = this->MakefileMap->GetDefinition(op);
+  if (cmNonempty(ret)) {
+    return cmIsOff(*ret);
   }
   return false;
 }
 
 bool cmCPackGenerator::IsSetToEmpty(const std::string& op) const
 {
-  const char* ret = this->MakefileMap->GetDefinition(op);
+  cmProp ret = this->MakefileMap->GetDefinition(op);
   if (ret) {
-    return !*ret;
+    return ret->empty();
   }
   return false;
 }
 
 const char* cmCPackGenerator::GetOption(const std::string& op) const
 {
-  const char* ret = this->MakefileMap->GetDefinition(op);
+  cmProp ret = this->MakefileMap->GetDefinition(op);
   if (!ret) {
     cmCPackLogger(cmCPackLog::LOG_DEBUG,
                   "Warning, GetOption return NULL for: " << op << std::endl);
+    return nullptr;
   }
-  return ret;
+  return ret->c_str();
 }
 
 std::vector<std::string> cmCPackGenerator::GetOptions() const
@@ -1289,7 +1329,7 @@ bool cmCPackGenerator::ConfigureFile(const std::string& inName,
                                      bool copyOnly /* = false */)
 {
   return this->MakefileMap->ConfigureFile(inName, outName, copyOnly, true,
-                                          false) == 1;
+                                          false, true) == 1;
 }
 
 int cmCPackGenerator::CleanTemporaryDirectory()
@@ -1378,7 +1418,8 @@ int cmCPackGenerator::PrepareGroupingKind()
           << std::endl);
   }
 
-  // if user specified packaging method, override the default packaging method
+  // if user specified packaging method, override the default packaging
+  // method
   if (method != UNKNOWN_COMPONENT_PACKAGE_METHOD) {
     componentPackageMethod = method;
   }
@@ -1471,7 +1512,7 @@ cmCPackInstallationType* cmCPackGenerator::GetInstallationType(
     installType->Name = name;
 
     const char* displayName = this->GetOption(macroPrefix + "_DISPLAY_NAME");
-    if (displayName && *displayName) {
+    if (cmNonempty(displayName)) {
       installType->DisplayName = displayName;
     } else {
       installType->DisplayName = installType->Name;
@@ -1493,7 +1534,7 @@ cmCPackComponent* cmCPackGenerator::GetComponent(
       "CPACK_COMPONENT_" + cmsys::SystemTools::UpperCase(name);
     component->Name = name;
     const char* displayName = this->GetOption(macroPrefix + "_DISPLAY_NAME");
-    if (displayName && *displayName) {
+    if (cmNonempty(displayName)) {
       component->DisplayName = displayName;
     } else {
       component->DisplayName = component->Name;
@@ -1505,17 +1546,17 @@ cmCPackComponent* cmCPackGenerator::GetComponent(
       cmIsOn(this->GetOption("CPACK_DOWNLOAD_ALL"));
 
     const char* archiveFile = this->GetOption(macroPrefix + "_ARCHIVE_FILE");
-    if (archiveFile && *archiveFile) {
+    if (cmNonempty(archiveFile)) {
       component->ArchiveFile = archiveFile;
     }
 
     const char* plist = this->GetOption(macroPrefix + "_PLIST");
-    if (plist && *plist) {
+    if (cmNonempty(plist)) {
       component->Plist = plist;
     }
 
     const char* groupName = this->GetOption(macroPrefix + "_GROUP");
-    if (groupName && *groupName) {
+    if (cmNonempty(groupName)) {
       component->Group = GetComponentGroup(projectName, groupName);
       component->Group->Components.push_back(component);
     } else {
@@ -1523,13 +1564,13 @@ cmCPackComponent* cmCPackGenerator::GetComponent(
     }
 
     const char* description = this->GetOption(macroPrefix + "_DESCRIPTION");
-    if (description && *description) {
+    if (cmNonempty(description)) {
       component->Description = description;
     }
 
     // Determine the installation types.
     const char* installTypes = this->GetOption(macroPrefix + "_INSTALL_TYPES");
-    if (installTypes && *installTypes) {
+    if (cmNonempty(installTypes)) {
       std::vector<std::string> installTypesVector =
         cmExpandedList(installTypes);
       for (std::string const& installType : installTypesVector) {
@@ -1540,7 +1581,7 @@ cmCPackComponent* cmCPackGenerator::GetComponent(
 
     // Determine the component dependencies.
     const char* depends = this->GetOption(macroPrefix + "_DEPENDS");
-    if (depends && *depends) {
+    if (cmNonempty(depends)) {
       std::vector<std::string> dependsVector = cmExpandedList(depends);
       for (std::string const& depend : dependsVector) {
         cmCPackComponent* child = GetComponent(projectName, depend);
@@ -1564,21 +1605,21 @@ cmCPackComponentGroup* cmCPackGenerator::GetComponentGroup(
     // Define the group
     group->Name = name;
     const char* displayName = this->GetOption(macroPrefix + "_DISPLAY_NAME");
-    if (displayName && *displayName) {
+    if (cmNonempty(displayName)) {
       group->DisplayName = displayName;
     } else {
       group->DisplayName = group->Name;
     }
 
     const char* description = this->GetOption(macroPrefix + "_DESCRIPTION");
-    if (description && *description) {
+    if (cmNonempty(description)) {
       group->Description = description;
     }
     group->IsBold = this->IsOn(macroPrefix + "_BOLD_TITLE");
     group->IsExpandedByDefault = this->IsOn(macroPrefix + "_EXPANDED");
     const char* parentGroupName =
       this->GetOption(macroPrefix + "_PARENT_GROUP");
-    if (parentGroupName && *parentGroupName) {
+    if (cmNonempty(parentGroupName)) {
       group->ParentGroup = GetComponentGroup(projectName, parentGroupName);
       group->ParentGroup->Subgroups.push_back(group);
     } else {
diff --git a/Source/CPack/cmCPackGenerator.h b/Source/CPack/cmCPackGenerator.h
index 33026c1..2512d42 100644
--- a/Source/CPack/cmCPackGenerator.h
+++ b/Source/CPack/cmCPackGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackGenerator_h
-#define cmCPackGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -339,5 +338,3 @@ protected:
     this->Logger->Log(logType, __FILE__, __LINE__,                            \
                       cmCPackLog_msg.str().c_str());                          \
   } while (false)
-
-#endif
diff --git a/Source/CPack/cmCPackGeneratorFactory.h b/Source/CPack/cmCPackGeneratorFactory.h
index 62b7484..0846573 100644
--- a/Source/CPack/cmCPackGeneratorFactory.h
+++ b/Source/CPack/cmCPackGeneratorFactory.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackGeneratorFactory_h
-#define cmCPackGeneratorFactory_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -44,5 +43,3 @@ private:
   DescriptionsMap GeneratorDescriptions;
   cmCPackLog* Logger;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackLog.h b/Source/CPack/cmCPackLog.h
index 68ffcce..6cec39c 100644
--- a/Source/CPack/cmCPackLog.h
+++ b/Source/CPack/cmCPackLog.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackLog_h
-#define cmCPackLog_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -139,5 +138,3 @@ inline std::ostream& operator<<(std::ostream& os, const cmCPackLogWrite& c)
   os.flush();
   return os;
 }
-
-#endif
diff --git a/Source/CPack/cmCPackNSISGenerator.cxx b/Source/CPack/cmCPackNSISGenerator.cxx
index 058b090..2109b4e 100644
--- a/Source/CPack/cmCPackNSISGenerator.cxx
+++ b/Source/CPack/cmCPackNSISGenerator.cxx
@@ -696,7 +696,7 @@ std::string cmCPackNSISGenerator::CreateComponentDescription(
     const char* userUploadDirectory =
       this->GetOption("CPACK_UPLOAD_DIRECTORY");
     std::string uploadDirectory;
-    if (userUploadDirectory && *userUploadDirectory) {
+    if (cmNonempty(userUploadDirectory)) {
       uploadDirectory = userUploadDirectory;
     } else {
       uploadDirectory =
diff --git a/Source/CPack/cmCPackNSISGenerator.h b/Source/CPack/cmCPackNSISGenerator.h
index 88cba45..ded02de 100644
--- a/Source/CPack/cmCPackNSISGenerator.h
+++ b/Source/CPack/cmCPackNSISGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackNSISGenerator_h
-#define cmCPackNSISGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -85,5 +84,3 @@ protected:
 
   bool Nsis64;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackNuGetGenerator.h b/Source/CPack/cmCPackNuGetGenerator.h
index a59db2d..609ec79 100644
--- a/Source/CPack/cmCPackNuGetGenerator.h
+++ b/Source/CPack/cmCPackNuGetGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackNuGetGenerator_h
-#define cmCPackNuGetGenerator_h
+#pragma once
 
 #include "cmCPackGenerator.h"
 
@@ -33,5 +32,3 @@ protected:
    */
   void AddGeneratedPackageNames();
 };
-
-#endif
diff --git a/Source/CPack/cmCPackOSXX11Generator.h b/Source/CPack/cmCPackOSXX11Generator.h
index a6461c8..8fae136 100644
--- a/Source/CPack/cmCPackOSXX11Generator.h
+++ b/Source/CPack/cmCPackOSXX11Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackOSXX11Generator_h
-#define cmCPackOSXX11Generator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -38,5 +37,3 @@ protected:
                              bool copyOnly = false);
   std::string InstallPrefix;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackPKGGenerator.h b/Source/CPack/cmCPackPKGGenerator.h
index be730ab..17cdcdf 100644
--- a/Source/CPack/cmCPackPKGGenerator.h
+++ b/Source/CPack/cmCPackPKGGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackPKGGenerator_h
-#define cmCPackPKGGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -94,5 +93,3 @@ protected:
   // The PostFlight component when creating a metapackage
   cmCPackComponent PostFlightComponent;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackPackageMakerGenerator.h b/Source/CPack/cmCPackPackageMakerGenerator.h
index 0575587..cda9277 100644
--- a/Source/CPack/cmCPackPackageMakerGenerator.h
+++ b/Source/CPack/cmCPackPackageMakerGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackPackageMakerGenerator_h
-#define cmCPackPackageMakerGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -49,5 +48,3 @@ protected:
   double PackageMakerVersion;
   unsigned int PackageCompatibilityVersion;
 };
-
-#endif
diff --git a/Source/CPack/cmCPackProductBuildGenerator.h b/Source/CPack/cmCPackProductBuildGenerator.h
index 015fe4a..462e2fc 100644
--- a/Source/CPack/cmCPackProductBuildGenerator.h
+++ b/Source/CPack/cmCPackProductBuildGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackProductBuildGenerator_h
-#define cmCPackProductBuildGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -49,5 +48,3 @@ protected:
   const char* GetComponentScript(const char* script,
                                  const char* script_component);
 };
-
-#endif
diff --git a/Source/CPack/cmCPackRPMGenerator.h b/Source/CPack/cmCPackRPMGenerator.h
index 075ce84..0288f2f 100644
--- a/Source/CPack/cmCPackRPMGenerator.h
+++ b/Source/CPack/cmCPackRPMGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackRPMGenerator_h
-#define cmCPackRPMGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -68,5 +67,3 @@ protected:
 
   void AddGeneratedPackageNames();
 };
-
-#endif
diff --git a/Source/CPack/cmCPackSTGZGenerator.h b/Source/CPack/cmCPackSTGZGenerator.h
index 79d7035..d2df1f2 100644
--- a/Source/CPack/cmCPackSTGZGenerator.h
+++ b/Source/CPack/cmCPackSTGZGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackSTGZGenerator_h
-#define cmCPackSTGZGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -30,5 +29,3 @@ protected:
   int InitializeInternal() override;
   int GenerateHeader(std::ostream* os) override;
 };
-
-#endif
diff --git a/Source/CPack/cpack.cxx b/Source/CPack/cpack.cxx
index 3a400b7..6c80753 100644
--- a/Source/CPack/cpack.cxx
+++ b/Source/CPack/cpack.cxx
@@ -12,6 +12,7 @@
 #include "cmDocumentationFormatter.h"
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStateSnapshot.h"
 #include "cmStringAlgorithms.h"
@@ -324,21 +325,22 @@ int main(int argc, char const* const* argv)
     }
 
     // Force CPACK_PACKAGE_DIRECTORY as absolute path
-    cpackProjectDirectory = globalMF.GetDefinition("CPACK_PACKAGE_DIRECTORY");
+    cpackProjectDirectory =
+      globalMF.GetSafeDefinition("CPACK_PACKAGE_DIRECTORY");
     cpackProjectDirectory =
       cmSystemTools::CollapseFullPath(cpackProjectDirectory);
     globalMF.AddDefinition("CPACK_PACKAGE_DIRECTORY", cpackProjectDirectory);
 
-    const char* cpackModulesPath = globalMF.GetDefinition("CPACK_MODULE_PATH");
+    cmProp cpackModulesPath = globalMF.GetDefinition("CPACK_MODULE_PATH");
     if (cpackModulesPath) {
-      globalMF.AddDefinition("CMAKE_MODULE_PATH", cpackModulesPath);
+      globalMF.AddDefinition("CMAKE_MODULE_PATH", *cpackModulesPath);
     }
-    const char* genList = globalMF.GetDefinition("CPACK_GENERATOR");
+    cmProp genList = globalMF.GetDefinition("CPACK_GENERATOR");
     if (!genList) {
       cmCPack_Log(&log, cmCPackLog::LOG_ERROR,
                   "CPack generator not specified" << std::endl);
     } else {
-      std::vector<std::string> generatorsVector = cmExpandedList(genList);
+      std::vector<std::string> generatorsVector = cmExpandedList(*genList);
       for (std::string const& gen : generatorsVector) {
         cmMakefile::ScopePushPop raii(&globalMF);
         cmMakefile* mf = &globalMF;
@@ -411,32 +413,31 @@ int main(int argc, char const* const* argv)
             parsed = 0;
           }
           if (parsed) {
-            const char* projName = mf->GetDefinition("CPACK_PACKAGE_NAME");
+            cmProp projName = mf->GetDefinition("CPACK_PACKAGE_NAME");
             cmCPack_Log(&log, cmCPackLog::LOG_VERBOSE,
                         "Use generator: " << cpackGenerator->GetNameOfClass()
                                           << std::endl);
             cmCPack_Log(&log, cmCPackLog::LOG_VERBOSE,
-                        "For project: " << projName << std::endl);
+                        "For project: " << *projName << std::endl);
 
-            const char* projVersion =
-              mf->GetDefinition("CPACK_PACKAGE_VERSION");
+            cmProp projVersion = mf->GetDefinition("CPACK_PACKAGE_VERSION");
             if (!projVersion) {
-              const char* projVersionMajor =
+              cmProp projVersionMajor =
                 mf->GetDefinition("CPACK_PACKAGE_VERSION_MAJOR");
-              const char* projVersionMinor =
+              cmProp projVersionMinor =
                 mf->GetDefinition("CPACK_PACKAGE_VERSION_MINOR");
-              const char* projVersionPatch =
+              cmProp projVersionPatch =
                 mf->GetDefinition("CPACK_PACKAGE_VERSION_PATCH");
               std::ostringstream ostr;
-              ostr << projVersionMajor << "." << projVersionMinor << "."
-                   << projVersionPatch;
+              ostr << *projVersionMajor << "." << *projVersionMinor << "."
+                   << *projVersionPatch;
               mf->AddDefinition("CPACK_PACKAGE_VERSION", ostr.str());
             }
 
             int res = cpackGenerator->DoPackage();
             if (!res) {
               cmCPack_Log(&log, cmCPackLog::LOG_ERROR,
-                          "Error when generating package: " << projName
+                          "Error when generating package: " << *projName
                                                             << std::endl);
               return 1;
             }
diff --git a/Source/CTest/cmCTestBZR.h b/Source/CTest/cmCTestBZR.h
index d7c6321..eb0dbbe 100644
--- a/Source/CTest/cmCTestBZR.h
+++ b/Source/CTest/cmCTestBZR.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestBZR_h
-#define cmCTestBZR_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -50,5 +49,3 @@ private:
   friend class UpdateParser;
   friend class StatusParser;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestBinPacker.h b/Source/CTest/cmCTestBinPacker.h
index ff02b85..e56a437 100644
--- a/Source/CTest/cmCTestBinPacker.h
+++ b/Source/CTest/cmCTestBinPacker.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestBinPacker_h
-#define cmCTestBinPacker_h
+#pragma once
 
 #include <cstddef>
 #include <map>
@@ -27,5 +26,3 @@ bool cmAllocateCTestResourcesRoundRobin(
 bool cmAllocateCTestResourcesBlock(
   const std::map<std::string, cmCTestResourceAllocator::Resource>& resources,
   std::vector<cmCTestBinPackerAllocation>& allocations);
-
-#endif
diff --git a/Source/CTest/cmCTestBuildAndTestHandler.cxx b/Source/CTest/cmCTestBuildAndTestHandler.cxx
index db426b2..a18cbb4 100644
--- a/Source/CTest/cmCTestBuildAndTestHandler.cxx
+++ b/Source/CTest/cmCTestBuildAndTestHandler.cxx
@@ -182,10 +182,9 @@ int cmCTestBuildAndTestHandler::RunCMakeAndTest(std::string* outstring)
     std::vector<std::string> extraPaths;
     std::vector<std::string> failed;
     fullPath = cmCTestTestHandler::FindExecutable(
-      this->CTest, this->ConfigSample.c_str(), resultingConfig, extraPaths,
-      failed);
+      this->CTest, this->ConfigSample, resultingConfig, extraPaths, failed);
     if (!fullPath.empty() && !resultingConfig.empty()) {
-      this->CTest->SetConfigType(resultingConfig.c_str());
+      this->CTest->SetConfigType(resultingConfig);
     }
     out << "Using config sample with results: " << fullPath << " and "
         << resultingConfig << std::endl;
@@ -296,9 +295,8 @@ int cmCTestBuildAndTestHandler::RunCMakeAndTest(std::string* outstring)
     extraPaths.push_back(tempPath);
   }
   std::vector<std::string> failed;
-  fullPath =
-    cmCTestTestHandler::FindExecutable(this->CTest, this->TestCommand.c_str(),
-                                       resultingConfig, extraPaths, failed);
+  fullPath = cmCTestTestHandler::FindExecutable(
+    this->CTest, this->TestCommand, resultingConfig, extraPaths, failed);
 
   if (!cmSystemTools::FileExists(fullPath)) {
     out << "Could not find path to executable, perhaps it was not built: "
diff --git a/Source/CTest/cmCTestBuildAndTestHandler.h b/Source/CTest/cmCTestBuildAndTestHandler.h
index 0c8a040..b9cc35c 100644
--- a/Source/CTest/cmCTestBuildAndTestHandler.h
+++ b/Source/CTest/cmCTestBuildAndTestHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestBuildAndTestHandler_h
-#define cmCTestBuildAndTestHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -71,5 +70,3 @@ protected:
   bool BuildNoCMake;
   cmDuration Timeout;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestBuildCommand.cxx b/Source/CTest/cmCTestBuildCommand.cxx
index 44fdc29..1cc267e 100644
--- a/Source/CTest/cmCTestBuildCommand.cxx
+++ b/Source/CTest/cmCTestBuildCommand.cxx
@@ -2,7 +2,6 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmCTestBuildCommand.h"
 
-#include <cstring>
 #include <sstream>
 
 #include <cmext/string_view>
@@ -12,6 +11,7 @@
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 #include "cmake.h"
@@ -38,13 +38,13 @@ cmCTestGenericHandler* cmCTestBuildCommand::InitializeHandler()
 
   this->Handler = handler;
 
-  const char* ctestBuildCommand =
+  cmProp ctestBuildCommand =
     this->Makefile->GetDefinition("CTEST_BUILD_COMMAND");
-  if (ctestBuildCommand && *ctestBuildCommand) {
-    this->CTest->SetCTestConfiguration("MakeCommand", ctestBuildCommand,
+  if (cmNonempty(ctestBuildCommand)) {
+    this->CTest->SetCTestConfiguration("MakeCommand", *ctestBuildCommand,
                                        this->Quiet);
   } else {
-    const char* cmakeGeneratorName =
+    cmProp cmakeGeneratorName =
       this->Makefile->GetDefinition("CTEST_CMAKE_GENERATOR");
 
     // Build configuration is determined by: CONFIGURATION argument,
@@ -52,49 +52,51 @@ cmCTestGenericHandler* cmCTestBuildCommand::InitializeHandler()
     // CTEST_CONFIGURATION_TYPE script variable, or ctest -C command
     // line argument... in that order.
     //
-    const char* ctestBuildConfiguration =
+    cmProp ctestBuildConfiguration =
       this->Makefile->GetDefinition("CTEST_BUILD_CONFIGURATION");
-    const char* cmakeBuildConfiguration = !this->Configuration.empty()
-      ? this->Configuration.c_str()
-      : ((ctestBuildConfiguration && *ctestBuildConfiguration)
-           ? ctestBuildConfiguration
-           : this->CTest->GetConfigType().c_str());
-
-    const char* cmakeBuildAdditionalFlags = !this->Flags.empty()
-      ? this->Flags.c_str()
+    const std::string* cmakeBuildConfiguration = !this->Configuration.empty()
+      ? &this->Configuration
+      : (cmNonempty(ctestBuildConfiguration) ? ctestBuildConfiguration
+                                             : &this->CTest->GetConfigType());
+
+    const std::string* cmakeBuildAdditionalFlags = !this->Flags.empty()
+      ? &this->Flags
       : this->Makefile->GetDefinition("CTEST_BUILD_FLAGS");
-    const char* cmakeBuildTarget = !this->Target.empty()
-      ? this->Target.c_str()
+    const std::string* cmakeBuildTarget = !this->Target.empty()
+      ? &this->Target
       : this->Makefile->GetDefinition("CTEST_BUILD_TARGET");
 
-    if (cmakeGeneratorName && *cmakeGeneratorName) {
+    if (cmNonempty(cmakeGeneratorName)) {
       if (!cmakeBuildConfiguration) {
-        cmakeBuildConfiguration = "Release";
+        static const std::string sRelease = "Release";
+        cmakeBuildConfiguration = &sRelease;
       }
       if (this->GlobalGenerator) {
-        if (this->GlobalGenerator->GetName() != cmakeGeneratorName) {
+        if (this->GlobalGenerator->GetName() != *cmakeGeneratorName) {
           this->GlobalGenerator.reset();
         }
       }
       if (!this->GlobalGenerator) {
         this->GlobalGenerator =
           this->Makefile->GetCMakeInstance()->CreateGlobalGenerator(
-            cmakeGeneratorName);
+            *cmakeGeneratorName);
         if (!this->GlobalGenerator) {
           std::string e = cmStrCat("could not create generator named \"",
-                                   cmakeGeneratorName, '"');
+                                   *cmakeGeneratorName, '"');
           this->Makefile->IssueMessage(MessageType::FATAL_ERROR, e);
           cmSystemTools::SetFatalErrorOccured();
           return nullptr;
         }
       }
-      if (strlen(cmakeBuildConfiguration) == 0) {
-        const char* config = nullptr;
+      if (cmakeBuildConfiguration->empty()) {
+        const std::string* config = nullptr;
 #ifdef CMAKE_INTDIR
-        config = CMAKE_INTDIR;
+        static const std::string sIntDir = CMAKE_INTDIR;
+        config = &sIntDir;
 #endif
         if (!config) {
-          config = "Debug";
+          static const std::string sDebug = "Debug";
+          config = &sDebug;
         }
         cmakeBuildConfiguration = config;
       }
@@ -102,13 +104,13 @@ cmCTestGenericHandler* cmCTestBuildCommand::InitializeHandler()
       std::string dir = this->CTest->GetCTestConfiguration("BuildDirectory");
       std::string buildCommand =
         this->GlobalGenerator->GenerateCMakeBuildCommand(
-          cmakeBuildTarget ? cmakeBuildTarget : "", cmakeBuildConfiguration,
-          cmakeBuildAdditionalFlags ? cmakeBuildAdditionalFlags : "",
+          cmakeBuildTarget ? *cmakeBuildTarget : "", *cmakeBuildConfiguration,
+          cmakeBuildAdditionalFlags ? *cmakeBuildAdditionalFlags : "",
           this->Makefile->IgnoreErrorsCMP0061());
       cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT,
                          "SetMakeCommand:" << buildCommand << "\n",
                          this->Quiet);
-      this->CTest->SetCTestConfiguration("MakeCommand", buildCommand.c_str(),
+      this->CTest->SetCTestConfiguration("MakeCommand", buildCommand,
                                          this->Quiet);
     } else {
       std::ostringstream ostr;
@@ -123,16 +125,16 @@ cmCTestGenericHandler* cmCTestBuildCommand::InitializeHandler()
     }
   }
 
-  if (const char* useLaunchers =
+  if (cmProp useLaunchers =
         this->Makefile->GetDefinition("CTEST_USE_LAUNCHERS")) {
-    this->CTest->SetCTestConfiguration("UseLaunchers", useLaunchers,
+    this->CTest->SetCTestConfiguration("UseLaunchers", *useLaunchers,
                                        this->Quiet);
   }
 
-  if (const char* labelsForSubprojects =
+  if (cmProp labelsForSubprojects =
         this->Makefile->GetDefinition("CTEST_LABELS_FOR_SUBPROJECTS")) {
     this->CTest->SetCTestConfiguration("LabelsForSubprojects",
-                                       labelsForSubprojects, this->Quiet);
+                                       *labelsForSubprojects, this->Quiet);
   }
 
   handler->SetQuiet(this->Quiet);
diff --git a/Source/CTest/cmCTestBuildCommand.h b/Source/CTest/cmCTestBuildCommand.h
index 0f82817..00dbcc4 100644
--- a/Source/CTest/cmCTestBuildCommand.h
+++ b/Source/CTest/cmCTestBuildCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestBuildCommand_h
-#define cmCTestBuildCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -62,5 +61,3 @@ protected:
   std::string Flags;
   std::string ProjectName;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestBuildHandler.cxx b/Source/CTest/cmCTestBuildHandler.cxx
index 35c2b11..9997548 100644
--- a/Source/CTest/cmCTestBuildHandler.cxx
+++ b/Source/CTest/cmCTestBuildHandler.cxx
@@ -19,6 +19,7 @@
 #include "cmGeneratedFileStream.h"
 #include "cmMakefile.h"
 #include "cmProcessOutput.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmStringReplaceHelper.h"
 #include "cmSystemTools.h"
@@ -248,13 +249,14 @@ void cmCTestBuildHandler::PopulateCustomVectors(cmMakefile* mf)
   }
 
   // Record the user-specified custom warning rules.
-  if (const char* customWarningMatchers =
+  if (cmProp customWarningMatchers =
         mf->GetDefinition("CTEST_CUSTOM_WARNING_MATCH")) {
-    cmExpandList(customWarningMatchers, this->ReallyCustomWarningMatches);
+    cmExpandList(*customWarningMatchers, this->ReallyCustomWarningMatches);
   }
-  if (const char* customWarningExceptions =
+  if (cmProp customWarningExceptions =
         mf->GetDefinition("CTEST_CUSTOM_WARNING_EXCEPTION")) {
-    cmExpandList(customWarningExceptions, this->ReallyCustomWarningExceptions);
+    cmExpandList(*customWarningExceptions,
+                 this->ReallyCustomWarningExceptions);
   }
 }
 
diff --git a/Source/CTest/cmCTestBuildHandler.h b/Source/CTest/cmCTestBuildHandler.h
index a5193f6..58e8d9c 100644
--- a/Source/CTest/cmCTestBuildHandler.h
+++ b/Source/CTest/cmCTestBuildHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestBuildHandler_h
-#define cmCTestBuildHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -156,5 +155,3 @@ private:
   friend class LaunchHelper;
   class FragmentCompare;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestCVS.h b/Source/CTest/cmCTestCVS.h
index 7d33d8f..d20239b 100644
--- a/Source/CTest/cmCTestCVS.h
+++ b/Source/CTest/cmCTestCVS.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestCVS_h
-#define cmCTestCVS_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -51,5 +50,3 @@ private:
   friend class LogParser;
   friend class UpdateParser;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestCommand.h b/Source/CTest/cmCTestCommand.h
index 8efb419..007378d 100644
--- a/Source/CTest/cmCTestCommand.h
+++ b/Source/CTest/cmCTestCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestCommand_h
-#define cmCTestCommand_h
+#pragma once
 
 #include "cmCommand.h"
 
@@ -27,5 +26,3 @@ public:
   cmCTest* CTest;
   cmCTestScriptHandler* CTestScriptHandler;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestConfigureCommand.cxx b/Source/CTest/cmCTestConfigureCommand.cxx
index f42c3f1..db9923e 100644
--- a/Source/CTest/cmCTestConfigureCommand.cxx
+++ b/Source/CTest/cmCTestConfigureCommand.cxx
@@ -12,6 +12,7 @@
 #include "cmCTestConfigureHandler.h"
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 #include "cmake.h"
@@ -38,16 +39,16 @@ cmCTestGenericHandler* cmCTestConfigureCommand::InitializeHandler()
     return nullptr;
   }
 
-  const char* ctestConfigureCommand =
+  cmProp ctestConfigureCommand =
     this->Makefile->GetDefinition("CTEST_CONFIGURE_COMMAND");
 
-  if (ctestConfigureCommand && *ctestConfigureCommand) {
+  if (cmNonempty(ctestConfigureCommand)) {
     this->CTest->SetCTestConfiguration("ConfigureCommand",
-                                       ctestConfigureCommand, this->Quiet);
+                                       *ctestConfigureCommand, this->Quiet);
   } else {
-    const char* cmakeGeneratorName =
+    cmProp cmakeGeneratorName =
       this->Makefile->GetDefinition("CTEST_CMAKE_GENERATOR");
-    if (cmakeGeneratorName && *cmakeGeneratorName) {
+    if (cmNonempty(cmakeGeneratorName)) {
       const std::string& source_dir =
         this->CTest->GetCTestConfiguration("SourceDirectory");
       if (source_dir.empty()) {
@@ -70,7 +71,7 @@ cmCTestGenericHandler* cmCTestConfigureCommand::InitializeHandler()
       bool cmakeBuildTypeInOptions = false;
 
       auto gg = this->Makefile->GetCMakeInstance()->CreateGlobalGenerator(
-        cmakeGeneratorName);
+        *cmakeGeneratorName);
       if (gg) {
         multiConfig = gg->IsMultiConfig();
         gg.reset();
@@ -102,22 +103,22 @@ cmCTestGenericHandler* cmCTestConfigureCommand::InitializeHandler()
       }
 
       cmakeConfigureCommand += " \"-G";
-      cmakeConfigureCommand += cmakeGeneratorName;
+      cmakeConfigureCommand += *cmakeGeneratorName;
       cmakeConfigureCommand += "\"";
 
-      const char* cmakeGeneratorPlatform =
+      cmProp cmakeGeneratorPlatform =
         this->Makefile->GetDefinition("CTEST_CMAKE_GENERATOR_PLATFORM");
-      if (cmakeGeneratorPlatform && *cmakeGeneratorPlatform) {
+      if (cmNonempty(cmakeGeneratorPlatform)) {
         cmakeConfigureCommand += " \"-A";
-        cmakeConfigureCommand += cmakeGeneratorPlatform;
+        cmakeConfigureCommand += *cmakeGeneratorPlatform;
         cmakeConfigureCommand += "\"";
       }
 
-      const char* cmakeGeneratorToolset =
+      cmProp cmakeGeneratorToolset =
         this->Makefile->GetDefinition("CTEST_CMAKE_GENERATOR_TOOLSET");
-      if (cmakeGeneratorToolset && *cmakeGeneratorToolset) {
+      if (cmNonempty(cmakeGeneratorToolset)) {
         cmakeConfigureCommand += " \"-T";
-        cmakeConfigureCommand += cmakeGeneratorToolset;
+        cmakeConfigureCommand += *cmakeGeneratorToolset;
         cmakeConfigureCommand += "\"";
       }
 
@@ -125,8 +126,8 @@ cmCTestGenericHandler* cmCTestConfigureCommand::InitializeHandler()
       cmakeConfigureCommand += source_dir;
       cmakeConfigureCommand += "\"";
 
-      this->CTest->SetCTestConfiguration(
-        "ConfigureCommand", cmakeConfigureCommand.c_str(), this->Quiet);
+      this->CTest->SetCTestConfiguration("ConfigureCommand",
+                                         cmakeConfigureCommand, this->Quiet);
     } else {
       this->SetError(
         "Configure command is not specified. If this is a "
@@ -136,10 +137,10 @@ cmCTestGenericHandler* cmCTestConfigureCommand::InitializeHandler()
     }
   }
 
-  if (const char* labelsForSubprojects =
+  if (cmProp labelsForSubprojects =
         this->Makefile->GetDefinition("CTEST_LABELS_FOR_SUBPROJECTS")) {
     this->CTest->SetCTestConfiguration("LabelsForSubprojects",
-                                       labelsForSubprojects, this->Quiet);
+                                       *labelsForSubprojects, this->Quiet);
   }
 
   cmCTestConfigureHandler* handler = this->CTest->GetConfigureHandler();
diff --git a/Source/CTest/cmCTestConfigureCommand.h b/Source/CTest/cmCTestConfigureCommand.h
index 3f5944a..f338637 100644
--- a/Source/CTest/cmCTestConfigureCommand.h
+++ b/Source/CTest/cmCTestConfigureCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestConfigureCommand_h
-#define cmCTestConfigureCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -45,5 +44,3 @@ protected:
 
   std::string Options;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestConfigureHandler.h b/Source/CTest/cmCTestConfigureHandler.h
index 01fe801..2aad98c 100644
--- a/Source/CTest/cmCTestConfigureHandler.h
+++ b/Source/CTest/cmCTestConfigureHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestConfigureHandler_h
-#define cmCTestConfigureHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -25,5 +24,3 @@ public:
 
   void Initialize() override;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestCoverageCommand.h b/Source/CTest/cmCTestCoverageCommand.h
index 76aaf46..9344852 100644
--- a/Source/CTest/cmCTestCoverageCommand.h
+++ b/Source/CTest/cmCTestCoverageCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestCoverageCommand_h
-#define cmCTestCoverageCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -48,5 +47,3 @@ protected:
   bool LabelsMentioned;
   std::vector<std::string> Labels;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestCoverageHandler.cxx b/Source/CTest/cmCTestCoverageHandler.cxx
index b839c10..093b2d1 100644
--- a/Source/CTest/cmCTestCoverageHandler.cxx
+++ b/Source/CTest/cmCTestCoverageHandler.cxx
@@ -469,8 +469,8 @@ int cmCTestCoverageHandler::ProcessHandler()
     }
 
     const std::string fileName = cmSystemTools::GetFilenameName(fullFileName);
-    std::string shortFileName =
-      this->CTest->GetShortPathToFile(fullFileName.c_str());
+    const std::string shortFileName =
+      this->CTest->GetShortPathToFile(fullFileName);
     const cmCTestCoverageHandlerContainer::SingleFileCoverageVector& fcov =
       file.second;
     covLogXML.StartElement("File");
@@ -538,7 +538,7 @@ int cmCTestCoverageHandler::ProcessHandler()
     covSumXML.StartElement("File");
     covSumXML.Attribute("Name", fileName);
     covSumXML.Attribute("FullPath",
-                        this->CTest->GetShortPathToFile(fullFileName.c_str()));
+                        this->CTest->GetShortPathToFile(fullFileName));
     covSumXML.Attribute("Covered", tested + untested > 0 ? "true" : "false");
     covSumXML.Element("LOCTested", tested);
     covSumXML.Element("LOCUnTested", untested);
@@ -1887,8 +1887,8 @@ int cmCTestCoverageHandler::RunBullseyeCoverageBranch(
         // start the file output
         covLogXML.StartElement("File");
         covLogXML.Attribute("Name", i->first);
-        covLogXML.Attribute(
-          "FullPath", this->CTest->GetShortPathToFile(i->second.c_str()));
+        covLogXML.Attribute("FullPath",
+                            this->CTest->GetShortPathToFile(i->second));
         covLogXML.StartElement("Report");
         // write the bullseye header
         line = 0;
@@ -2064,8 +2064,7 @@ int cmCTestCoverageHandler::RunBullseyeSourceSummary(
       total_untested += (totalFunctions - functionsCalled);
 
       std::string fileName = cmSystemTools::GetFilenameName(file);
-      std::string shortFileName =
-        this->CTest->GetShortPathToFile(file.c_str());
+      std::string shortFileName = this->CTest->GetShortPathToFile(file);
 
       float cper = static_cast<float>(percentBranch + percentFunction);
       if (totalBranches > 0) {
@@ -2266,7 +2265,7 @@ void cmCTestCoverageHandler::LoadLabels(const char* dir)
       // is the end of the target-wide labels.
       inTarget = false;
 
-      source = this->CTest->GetShortPathToFile(line.c_str());
+      source = this->CTest->GetShortPathToFile(line);
 
       // Label the source with the target labels.
       LabelSet& labelSet = this->SourceLabels[source];
@@ -2320,7 +2319,7 @@ bool cmCTestCoverageHandler::IsFilteredOut(std::string const& source)
 
   // The source is filtered out if it does not have any labels in
   // common with the filter set.
-  std::string shortSrc = this->CTest->GetShortPathToFile(source.c_str());
+  std::string shortSrc = this->CTest->GetShortPathToFile(source);
   auto li = this->SourceLabels.find(shortSrc);
   if (li != this->SourceLabels.end()) {
     return !this->IntersectsFilter(li->second);
@@ -2342,14 +2341,14 @@ std::set<std::string> cmCTestCoverageHandler::FindUncoveredFiles(
     std::vector<std::string> files = gl.GetFiles();
     for (std::string const& f : files) {
       if (this->ShouldIDoCoverage(f, cont->SourceDir, cont->BinaryDir)) {
-        extraMatches.insert(this->CTest->GetShortPathToFile(f.c_str()));
+        extraMatches.insert(this->CTest->GetShortPathToFile(f));
       }
     }
   }
 
   if (!extraMatches.empty()) {
     for (auto const& i : cont->TotalCoverage) {
-      std::string shortPath = this->CTest->GetShortPathToFile(i.first.c_str());
+      std::string shortPath = this->CTest->GetShortPathToFile(i.first);
       extraMatches.erase(shortPath);
     }
   }
diff --git a/Source/CTest/cmCTestCoverageHandler.h b/Source/CTest/cmCTestCoverageHandler.h
index 991b89d..8732723 100644
--- a/Source/CTest/cmCTestCoverageHandler.h
+++ b/Source/CTest/cmCTestCoverageHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestCoverageHandler_h
-#define cmCTestCoverageHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -149,5 +148,3 @@ private:
   bool IntersectsFilter(LabelSet const& labels);
   bool IsFilteredOut(std::string const& source);
 };
-
-#endif
diff --git a/Source/CTest/cmCTestCurl.h b/Source/CTest/cmCTestCurl.h
index b0d7f07..d9aa916 100644
--- a/Source/CTest/cmCTestCurl.h
+++ b/Source/CTest/cmCTestCurl.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestCurl_h
-#define cmCTestCurl_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -52,5 +51,3 @@ private:
   bool Quiet;
   int TimeOutSeconds;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestEmptyBinaryDirectoryCommand.h b/Source/CTest/cmCTestEmptyBinaryDirectoryCommand.h
index ac96a4e..ba2b0eb 100644
--- a/Source/CTest/cmCTestEmptyBinaryDirectoryCommand.h
+++ b/Source/CTest/cmCTestEmptyBinaryDirectoryCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestEmptyBinaryDirectoryCommand_h
-#define cmCTestEmptyBinaryDirectoryCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -45,5 +44,3 @@ public:
   bool InitialPass(std::vector<std::string> const& args,
                    cmExecutionStatus& status) override;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestGIT.h b/Source/CTest/cmCTestGIT.h
index 3103d84..a15aef5 100644
--- a/Source/CTest/cmCTestGIT.h
+++ b/Source/CTest/cmCTestGIT.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestGIT_h
-#define cmCTestGIT_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -53,5 +52,3 @@ public:
   friend class DiffParser;
   friend class OneLineParser;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestGenericHandler.cxx b/Source/CTest/cmCTestGenericHandler.cxx
index cc0b4ed..a71f550 100644
--- a/Source/CTest/cmCTestGenericHandler.cxx
+++ b/Source/CTest/cmCTestGenericHandler.cxx
@@ -100,7 +100,7 @@ bool cmCTestGenericHandler::StartResultingXML(cmCTest::Part part,
                                                     << std::endl);
     return false;
   }
-  this->CTest->AddSubmitFile(part, ostr.str().c_str());
+  this->CTest->AddSubmitFile(part, ostr.str());
   return true;
 }
 
diff --git a/Source/CTest/cmCTestGenericHandler.h b/Source/CTest/cmCTestGenericHandler.h
index 94e5418..591d9cd 100644
--- a/Source/CTest/cmCTestGenericHandler.h
+++ b/Source/CTest/cmCTestGenericHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestGenericHandler_h
-#define cmCTestGenericHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -105,5 +104,3 @@ protected:
   cmCTestCommand* Command;
   int SubmitIndex;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestGlobalVC.h b/Source/CTest/cmCTestGlobalVC.h
index ff86591..679b0e1 100644
--- a/Source/CTest/cmCTestGlobalVC.h
+++ b/Source/CTest/cmCTestGlobalVC.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestGlobalVC_h
-#define cmCTestGlobalVC_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -73,5 +72,3 @@ protected:
   void WriteXMLDirectory(cmXMLWriter& xml, std::string const& path,
                          Directory const& dir);
 };
-
-#endif
diff --git a/Source/CTest/cmCTestHG.h b/Source/CTest/cmCTestHG.h
index 2900139..b81f042 100644
--- a/Source/CTest/cmCTestHG.h
+++ b/Source/CTest/cmCTestHG.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestHG_h
-#define cmCTestHG_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -42,5 +41,3 @@ private:
   friend class LogParser;
   friend class StatusParser;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestHandlerCommand.cxx b/Source/CTest/cmCTestHandlerCommand.cxx
index a755632..731932e 100644
--- a/Source/CTest/cmCTestHandlerCommand.cxx
+++ b/Source/CTest/cmCTestHandlerCommand.cxx
@@ -14,6 +14,7 @@
 #include "cmExecutionStatus.h"
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 #include "cmWorkingDirectory.h"
@@ -125,23 +126,22 @@ bool cmCTestHandlerCommand::InitialPass(std::vector<std::string> const& args,
   // CTEST_CONFIGURATION_TYPE script variable if it is defined.
   // The current script value trumps the -C argument on the command
   // line.
-  const char* ctestConfigType =
+  cmProp ctestConfigType =
     this->Makefile->GetDefinition("CTEST_CONFIGURATION_TYPE");
   if (ctestConfigType) {
-    this->CTest->SetConfigType(ctestConfigType);
+    this->CTest->SetConfigType(*ctestConfigType);
   }
 
   if (!this->Build.empty()) {
     this->CTest->SetCTestConfiguration(
-      "BuildDirectory", cmSystemTools::CollapseFullPath(this->Build).c_str(),
+      "BuildDirectory", cmSystemTools::CollapseFullPath(this->Build),
       this->Quiet);
   } else {
     std::string const& bdir =
       this->Makefile->GetSafeDefinition("CTEST_BINARY_DIRECTORY");
     if (!bdir.empty()) {
       this->CTest->SetCTestConfiguration(
-        "BuildDirectory", cmSystemTools::CollapseFullPath(bdir).c_str(),
-        this->Quiet);
+        "BuildDirectory", cmSystemTools::CollapseFullPath(bdir), this->Quiet);
     } else {
       cmCTestLog(this->CTest, ERROR_MESSAGE,
                  "CTEST_BINARY_DIRECTORY not set" << std::endl;);
@@ -151,20 +151,18 @@ bool cmCTestHandlerCommand::InitialPass(std::vector<std::string> const& args,
     cmCTestLog(this->CTest, DEBUG,
                "Set source directory to: " << this->Source << std::endl);
     this->CTest->SetCTestConfiguration(
-      "SourceDirectory", cmSystemTools::CollapseFullPath(this->Source).c_str(),
+      "SourceDirectory", cmSystemTools::CollapseFullPath(this->Source),
       this->Quiet);
   } else {
     this->CTest->SetCTestConfiguration(
       "SourceDirectory",
       cmSystemTools::CollapseFullPath(
-        this->Makefile->GetSafeDefinition("CTEST_SOURCE_DIRECTORY"))
-        .c_str(),
+        this->Makefile->GetSafeDefinition("CTEST_SOURCE_DIRECTORY")),
       this->Quiet);
   }
 
-  if (const char* changeId =
-        this->Makefile->GetDefinition("CTEST_CHANGE_ID")) {
-    this->CTest->SetCTestConfiguration("ChangeId", changeId, this->Quiet);
+  if (cmProp changeId = this->Makefile->GetDefinition("CTEST_CHANGE_ID")) {
+    this->CTest->SetCTestConfiguration("ChangeId", *changeId, this->Quiet);
   }
 
   cmCTestLog(this->CTest, DEBUG, "Initialize handler" << std::endl;);
diff --git a/Source/CTest/cmCTestHandlerCommand.h b/Source/CTest/cmCTestHandlerCommand.h
index a20d607..756952d 100644
--- a/Source/CTest/cmCTestHandlerCommand.h
+++ b/Source/CTest/cmCTestHandlerCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestHandlerCommand_h
-#define cmCTestHandlerCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -58,5 +57,3 @@ protected:
   "The APPEND option marks results for append to those previously "           \
   "submitted to a dashboard server since the last ctest_start.  "             \
   "Append semantics are defined by the dashboard server in use."
-
-#endif
diff --git a/Source/CTest/cmCTestLaunch.h b/Source/CTest/cmCTestLaunch.h
index 79a7712..33ff82c 100644
--- a/Source/CTest/cmCTestLaunch.h
+++ b/Source/CTest/cmCTestLaunch.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestLaunch_h
-#define cmCTestLaunch_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -103,5 +102,3 @@ private:
   void LoadConfig();
   std::string SourceDir;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestMemCheckCommand.h b/Source/CTest/cmCTestMemCheckCommand.h
index 8f4ffb8..6544f16 100644
--- a/Source/CTest/cmCTestMemCheckCommand.h
+++ b/Source/CTest/cmCTestMemCheckCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestMemCheckCommand_h
-#define cmCTestMemCheckCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -43,5 +42,3 @@ protected:
 
   std::string DefectCount;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestMemCheckHandler.cxx b/Source/CTest/cmCTestMemCheckHandler.cxx
index 85b8ab1..8b31e4b 100644
--- a/Source/CTest/cmCTestMemCheckHandler.cxx
+++ b/Source/CTest/cmCTestMemCheckHandler.cxx
@@ -326,6 +326,9 @@ void cmCTestMemCheckHandler::GenerateDartOutput(cmXMLWriter& xml)
     case cmCTestMemCheckHandler::BOUNDS_CHECKER:
       xml.Attribute("Checker", "BoundsChecker");
       break;
+    case cmCTestMemCheckHandler::CUDA_MEMCHECK:
+      xml.Attribute("Checker", "CudaMemcheck");
+      break;
     case cmCTestMemCheckHandler::ADDRESS_SANITIZER:
       xml.Attribute("Checker", "AddressSanitizer");
       break;
@@ -351,7 +354,7 @@ void cmCTestMemCheckHandler::GenerateDartOutput(cmXMLWriter& xml)
   cmCTestMemCheckHandler::TestResultsVector::size_type cc;
   for (cmCTestTestResult const& result : this->TestResults) {
     std::string testPath = result.Path + "/" + result.Name;
-    xml.Element("Test", this->CTest->GetShortPathToFile(testPath.c_str()));
+    xml.Element("Test", this->CTest->GetShortPathToFile(testPath));
   }
   xml.EndElement(); // TestList
   cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
@@ -465,6 +468,8 @@ bool cmCTestMemCheckHandler::InitializeMemoryChecking()
       this->MemoryTesterStyle = cmCTestMemCheckHandler::PURIFY;
     } else if (testerName.find("BC") != std::string::npos) {
       this->MemoryTesterStyle = cmCTestMemCheckHandler::BOUNDS_CHECKER;
+    } else if (testerName.find("cuda-memcheck") != std::string::npos) {
+      this->MemoryTesterStyle = cmCTestMemCheckHandler::CUDA_MEMCHECK;
     } else {
       this->MemoryTesterStyle = cmCTestMemCheckHandler::UNKNOWN;
     }
@@ -485,6 +490,11 @@ bool cmCTestMemCheckHandler::InitializeMemoryChecking()
     this->MemoryTester =
       this->CTest->GetCTestConfiguration("BoundsCheckerCommand");
     this->MemoryTesterStyle = cmCTestMemCheckHandler::BOUNDS_CHECKER;
+  } else if (cmSystemTools::FileExists(
+               this->CTest->GetCTestConfiguration("CudaMemcheckCommand"))) {
+    this->MemoryTester =
+      this->CTest->GetCTestConfiguration("CudaMemcheckCommand");
+    this->MemoryTesterStyle = cmCTestMemCheckHandler::CUDA_MEMCHECK;
   }
   if (this->CTest->GetCTestConfiguration("MemoryCheckType") ==
       "AddressSanitizer") {
@@ -528,6 +538,8 @@ bool cmCTestMemCheckHandler::InitializeMemoryChecking()
       this->MemoryTesterStyle = cmCTestMemCheckHandler::VALGRIND;
     } else if (checkType == "DrMemory") {
       this->MemoryTesterStyle = cmCTestMemCheckHandler::DRMEMORY;
+    } else if (checkType == "CudaMemcheck") {
+      this->MemoryTesterStyle = cmCTestMemCheckHandler::CUDA_MEMCHECK;
     }
   }
   if (this->MemoryTester.empty()) {
@@ -553,6 +565,10 @@ bool cmCTestMemCheckHandler::InitializeMemoryChecking()
                 .empty()) {
     memoryTesterOptions =
       this->CTest->GetCTestConfiguration("DrMemoryCommandOptions");
+  } else if (!this->CTest->GetCTestConfiguration("CudaMemcheckCommandOptions")
+                .empty()) {
+    memoryTesterOptions =
+      this->CTest->GetCTestConfiguration("CudaMemcheckCommandOptions");
   }
   this->MemoryTesterOptions =
     cmSystemTools::ParseArguments(memoryTesterOptions);
@@ -686,6 +702,18 @@ bool cmCTestMemCheckHandler::InitializeMemoryChecking()
       this->MemoryTesterOptions.emplace_back("/M");
       break;
     }
+    case cmCTestMemCheckHandler::CUDA_MEMCHECK: {
+      // cuda-memcheck separates flags from arguments by spaces
+      if (this->MemoryTesterOptions.empty()) {
+        this->MemoryTesterOptions.emplace_back("--tool");
+        this->MemoryTesterOptions.emplace_back("memcheck");
+        this->MemoryTesterOptions.emplace_back("--leak-check");
+        this->MemoryTesterOptions.emplace_back("full");
+      }
+      this->MemoryTesterDynamicOptions.emplace_back("--log-file");
+      this->MemoryTesterDynamicOptions.push_back(this->MemoryTesterOutputFile);
+      break;
+    }
     // these are almost the same but the env var used is different
     case cmCTestMemCheckHandler::ADDRESS_SANITIZER:
     case cmCTestMemCheckHandler::LEAK_SANITIZER:
@@ -771,6 +799,8 @@ bool cmCTestMemCheckHandler::ProcessMemCheckOutput(const std::string& str,
       return this->ProcessMemCheckSanitizerOutput(str, log, results);
     case cmCTestMemCheckHandler::BOUNDS_CHECKER:
       return this->ProcessMemCheckBoundsCheckerOutput(str, log, results);
+    case cmCTestMemCheckHandler::CUDA_MEMCHECK:
+      return this->ProcessMemCheckCudaOutput(str, log, results);
     default:
       log.append("\nMemory checking style used was: ");
       log.append("None that I know");
@@ -1103,6 +1133,119 @@ bool cmCTestMemCheckHandler::ProcessMemCheckBoundsCheckerOutput(
   return defects == 0;
 }
 
+bool cmCTestMemCheckHandler::ProcessMemCheckCudaOutput(
+  const std::string& str, std::string& log, std::vector<int>& results)
+{
+  std::vector<std::string> lines;
+  cmsys::SystemTools::Split(str, lines);
+  bool unlimitedOutput = false;
+  if (str.find("CTEST_FULL_OUTPUT") != std::string::npos ||
+      this->CustomMaximumFailedTestOutputSize == 0) {
+    unlimitedOutput = true;
+  }
+
+  std::string::size_type cc;
+
+  std::ostringstream ostr;
+  log.clear();
+
+  int defects = 0;
+
+  cmsys::RegularExpression memcheckLine("^========");
+
+  cmsys::RegularExpression leakExpr("== Leaked [0-9,]+ bytes at");
+
+  // list of matchers for output messages that contain variable content
+  // (addresses, sizes, ...) or can be shortened in general. the first match is
+  // used as a error name.
+  std::vector<cmsys::RegularExpression> matchers{
+    // API errors
+    "== Malloc/Free error encountered: (.*)",
+    "== Program hit error ([^ ]*).* on CUDA API call to",
+    "== Program hit ([^ ]*).* on CUDA API call to",
+    // memcheck
+    "== (Invalid .*) of size [0-9,]+", "== (Fatal UVM [CG]PU fault)",
+    // racecheck
+    "== .* (Potential .* hazard detected)", "== .* (Race reported)",
+    // synccheck
+    "== (Barrier error)",
+    // initcheck
+    "== (Uninitialized .* memory read)", "== (Unused memory)",
+    "== (Host API memory access error)",
+    // generic error: ignore ERROR SUMMARY, CUDA-MEMCHECK and others
+    "== ([A-Z][a-z].*)"
+  };
+
+  std::vector<std::string::size_type> nonMemcheckOutput;
+  auto sttime = std::chrono::steady_clock::now();
+  cmCTestOptionalLog(this->CTest, DEBUG,
+                     "Start test: " << lines.size() << std::endl, this->Quiet);
+  std::string::size_type totalOutputSize = 0;
+  for (cc = 0; cc < lines.size(); cc++) {
+    cmCTestOptionalLog(this->CTest, DEBUG,
+                       "test line " << lines[cc] << std::endl, this->Quiet);
+
+    if (memcheckLine.find(lines[cc])) {
+      cmCTestOptionalLog(this->CTest, DEBUG,
+                         "cuda-memcheck line " << lines[cc] << std::endl,
+                         this->Quiet);
+      int failure = -1;
+      auto& line = lines[cc];
+      if (leakExpr.find(line)) {
+        failure = static_cast<int>(this->FindOrAddWarning("Memory leak"));
+      } else {
+        for (auto& matcher : matchers) {
+          if (matcher.find(line)) {
+            failure =
+              static_cast<int>(this->FindOrAddWarning(matcher.match(1)));
+            break;
+          }
+        }
+      }
+
+      if (failure >= 0) {
+        ostr << "<b>" << this->ResultStrings[failure] << "</b> ";
+        if (results.empty() || unsigned(failure) > results.size() - 1) {
+          results.push_back(1);
+        } else {
+          results[failure]++;
+        }
+        defects++;
+      }
+      totalOutputSize += lines[cc].size();
+      ostr << lines[cc] << std::endl;
+    } else {
+      nonMemcheckOutput.push_back(cc);
+    }
+  }
+  // Now put all all the non cuda-memcheck output into the test output
+  // This should be last in case it gets truncated by the output
+  // limiting code
+  for (std::string::size_type i : nonMemcheckOutput) {
+    totalOutputSize += lines[i].size();
+    ostr << lines[i] << std::endl;
+    if (!unlimitedOutput &&
+        totalOutputSize >
+          static_cast<size_t>(this->CustomMaximumFailedTestOutputSize)) {
+      ostr << "....\n";
+      ostr << "Test Output for this test has been truncated see testing"
+              " machine logs for full output,\n";
+      ostr << "or put CTEST_FULL_OUTPUT in the output of "
+              "this test program.\n";
+      break; // stop the copy of output if we are full
+    }
+  }
+  cmCTestOptionalLog(this->CTest, DEBUG,
+                     "End test (elapsed: "
+                       << cmDurationTo<unsigned int>(
+                            std::chrono::steady_clock::now() - sttime)
+                       << "s)" << std::endl,
+                     this->Quiet);
+  log = ostr.str();
+  this->DefectCount += defects;
+  return defects == 0;
+}
+
 // PostProcessTest memcheck results
 void cmCTestMemCheckHandler::PostProcessTest(cmCTestTestResult& res, int test)
 {
diff --git a/Source/CTest/cmCTestMemCheckHandler.h b/Source/CTest/cmCTestMemCheckHandler.h
index 52667f8..6ef5d20 100644
--- a/Source/CTest/cmCTestMemCheckHandler.h
+++ b/Source/CTest/cmCTestMemCheckHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestMemCheckHandler_h
-#define cmCTestMemCheckHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -46,6 +45,7 @@ private:
     DRMEMORY,
     BOUNDS_CHECKER,
     // checkers after here do not use the standard error list
+    CUDA_MEMCHECK,
     ADDRESS_SANITIZER,
     LEAK_SANITIZER,
     THREAD_SANITIZER,
@@ -137,6 +137,8 @@ private:
                                      std::vector<int>& results);
   bool ProcessMemCheckPurifyOutput(const std::string& str, std::string& log,
                                    std::vector<int>& results);
+  bool ProcessMemCheckCudaOutput(const std::string& str, std::string& log,
+                                 std::vector<int>& results);
   bool ProcessMemCheckSanitizerOutput(const std::string& str, std::string& log,
                                       std::vector<int>& results);
   bool ProcessMemCheckBoundsCheckerOutput(const std::string& str,
@@ -154,5 +156,3 @@ private:
   //! generate the output filename for the given test index
   void TestOutputFileNames(int test, std::vector<std::string>& files);
 };
-
-#endif
diff --git a/Source/CTest/cmCTestMultiProcessHandler.h b/Source/CTest/cmCTestMultiProcessHandler.h
index e21b912..5de42f9 100644
--- a/Source/CTest/cmCTestMultiProcessHandler.h
+++ b/Source/CTest/cmCTestMultiProcessHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestMultiProcessHandler_h
-#define cmCTestMultiProcessHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -200,5 +199,3 @@ protected:
   bool Quiet;
   bool SerialTestRunning;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestP4.h b/Source/CTest/cmCTestP4.h
index e19472e..d03f9cb 100644
--- a/Source/CTest/cmCTestP4.h
+++ b/Source/CTest/cmCTestP4.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestP4_h
-#define cmCTestP4_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -72,5 +71,3 @@ private:
   friend class DescribeParser;
   friend class DiffParser;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestReadCustomFilesCommand.cxx b/Source/CTest/cmCTestReadCustomFilesCommand.cxx
index ed14d06..a25cca4 100644
--- a/Source/CTest/cmCTestReadCustomFilesCommand.cxx
+++ b/Source/CTest/cmCTestReadCustomFilesCommand.cxx
@@ -15,7 +15,7 @@ bool cmCTestReadCustomFilesCommand::InitialPass(
   }
 
   for (std::string const& arg : args) {
-    this->CTest->ReadCustomConfigurationFileTree(arg.c_str(), this->Makefile);
+    this->CTest->ReadCustomConfigurationFileTree(arg, this->Makefile);
   }
 
   return true;
diff --git a/Source/CTest/cmCTestReadCustomFilesCommand.h b/Source/CTest/cmCTestReadCustomFilesCommand.h
index cbb9390..03714f6 100644
--- a/Source/CTest/cmCTestReadCustomFilesCommand.h
+++ b/Source/CTest/cmCTestReadCustomFilesCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestReadCustomFilesCommand_h
-#define cmCTestReadCustomFilesCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -44,5 +43,3 @@ public:
   bool InitialPass(std::vector<std::string> const& args,
                    cmExecutionStatus& status) override;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestResourceAllocator.h b/Source/CTest/cmCTestResourceAllocator.h
index 9f0b9c9..129e64e 100644
--- a/Source/CTest/cmCTestResourceAllocator.h
+++ b/Source/CTest/cmCTestResourceAllocator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestResourceAllocator_h
-#define cmCTestResourceAllocator_h
+#pragma once
 
 #include <map>
 #include <string>
@@ -35,5 +34,3 @@ public:
 private:
   std::map<std::string, std::map<std::string, Resource>> Resources;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestResourceGroupsLexerHelper.h b/Source/CTest/cmCTestResourceGroupsLexerHelper.h
index 2cb6cb1..ae4fa99 100644
--- a/Source/CTest/cmCTestResourceGroupsLexerHelper.h
+++ b/Source/CTest/cmCTestResourceGroupsLexerHelper.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestResourceGroupsLexerHelper_h
-#define cmCTestResourceGroupsLexerHelper_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -40,5 +39,3 @@ private:
 };
 
 #define YY_EXTRA_TYPE cmCTestResourceGroupsLexerHelper*
-
-#endif
diff --git a/Source/CTest/cmCTestResourceSpec.h b/Source/CTest/cmCTestResourceSpec.h
index cb242c0..1aa279b 100644
--- a/Source/CTest/cmCTestResourceSpec.h
+++ b/Source/CTest/cmCTestResourceSpec.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestResourceSpec_h
-#define cmCTestResourceSpec_h
+#pragma once
 
 #include <map>
 #include <string>
@@ -51,5 +50,3 @@ public:
   bool operator==(const cmCTestResourceSpec& other) const;
   bool operator!=(const cmCTestResourceSpec& other) const;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestRunScriptCommand.h b/Source/CTest/cmCTestRunScriptCommand.h
index 2d8bde1..510b748 100644
--- a/Source/CTest/cmCTestRunScriptCommand.h
+++ b/Source/CTest/cmCTestRunScriptCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestRunScriptCommand_h
-#define cmCTestRunScriptCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -45,5 +44,3 @@ public:
   bool InitialPass(std::vector<std::string> const& args,
                    cmExecutionStatus& status) override;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestRunTest.cxx b/Source/CTest/cmCTestRunTest.cxx
index 2c8e385..4d65c9b 100644
--- a/Source/CTest/cmCTestRunTest.cxx
+++ b/Source/CTest/cmCTestRunTest.cxx
@@ -619,11 +619,11 @@ void cmCTestRunTest::ComputeArguments()
     cmCTestMemCheckHandler* handler =
       static_cast<cmCTestMemCheckHandler*>(this->TestHandler);
     this->ActualCommand = handler->MemoryTester;
-    this->TestProperties->Args[1] = this->TestHandler->FindTheExecutable(
-      this->TestProperties->Args[1].c_str());
+    this->TestProperties->Args[1] =
+      this->TestHandler->FindTheExecutable(this->TestProperties->Args[1]);
   } else {
-    this->ActualCommand = this->TestHandler->FindTheExecutable(
-      this->TestProperties->Args[1].c_str());
+    this->ActualCommand =
+      this->TestHandler->FindTheExecutable(this->TestProperties->Args[1]);
     ++j; // skip the executable (it will be actualCommand)
   }
   std::string testCommand =
diff --git a/Source/CTest/cmCTestRunTest.h b/Source/CTest/cmCTestRunTest.h
index d831247..863ac1b 100644
--- a/Source/CTest/cmCTestRunTest.h
+++ b/Source/CTest/cmCTestRunTest.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestRunTest_h
-#define cmCTestRunTest_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -159,5 +158,3 @@ inline int getNumWidth(size_t n)
   }
   return w;
 }
-
-#endif
diff --git a/Source/CTest/cmCTestSVN.h b/Source/CTest/cmCTestSVN.h
index b74dc12..370d176 100644
--- a/Source/CTest/cmCTestSVN.h
+++ b/Source/CTest/cmCTestSVN.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestSVN_h
-#define cmCTestSVN_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -103,5 +102,3 @@ private:
   friend class UpdateParser;
   friend class ExternalParser;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestScriptHandler.cxx b/Source/CTest/cmCTestScriptHandler.cxx
index 4fa4dc0..4808c36 100644
--- a/Source/CTest/cmCTestScriptHandler.cxx
+++ b/Source/CTest/cmCTestScriptHandler.cxx
@@ -35,6 +35,7 @@
 #include "cmGeneratedFileStream.h"
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStateDirectory.h"
 #include "cmStateSnapshot.h"
@@ -372,8 +373,8 @@ int cmCTestScriptHandler::ReadInScript(const std::string& total_script_arg)
 int cmCTestScriptHandler::ExtractVariables()
 {
   // Temporary variables
-  const char* minInterval;
-  const char* contDuration;
+  cmProp minInterval;
+  cmProp contDuration;
 
   this->SourceDir =
     this->Makefile->GetSafeDefinition("CTEST_SOURCE_DIRECTORY");
@@ -412,7 +413,7 @@ int cmCTestScriptHandler::ExtractVariables()
   int i;
   for (i = 1; i < 10; ++i) {
     sprintf(updateVar, "CTEST_EXTRA_UPDATES_%i", i);
-    const char* updateVal = this->Makefile->GetDefinition(updateVar);
+    cmProp updateVal = this->Makefile->GetDefinition(updateVar);
     if (updateVal) {
       if (this->UpdateCmd.empty()) {
         cmSystemTools::Error(
@@ -420,7 +421,7 @@ int cmCTestScriptHandler::ExtractVariables()
           " specified without specifying CTEST_CVS_COMMAND.");
         return 12;
       }
-      this->ExtraUpdates.emplace_back(updateVal);
+      this->ExtraUpdates.emplace_back(*updateVal);
     }
   }
 
@@ -455,10 +456,10 @@ int cmCTestScriptHandler::ExtractVariables()
 
   // the script may override the minimum continuous interval
   if (minInterval) {
-    this->MinimumInterval = 60 * atof(minInterval);
+    this->MinimumInterval = 60 * atof(minInterval->c_str());
   }
   if (contDuration) {
-    this->ContinuousDuration = 60.0 * atof(contDuration);
+    this->ContinuousDuration = 60.0 * atof(contDuration->c_str());
   }
 
   this->UpdateElapsedTime();
@@ -932,13 +933,13 @@ cmDuration cmCTestScriptHandler::GetRemainingTimeAllowed()
     return cmCTest::MaxDuration();
   }
 
-  const char* timelimitS = this->Makefile->GetDefinition("CTEST_TIME_LIMIT");
+  cmProp timelimitS = this->Makefile->GetDefinition("CTEST_TIME_LIMIT");
 
   if (!timelimitS) {
     return cmCTest::MaxDuration();
   }
 
-  auto timelimit = cmDuration(atof(timelimitS));
+  auto timelimit = cmDuration(atof(timelimitS->c_str()));
 
   auto duration = std::chrono::duration_cast<cmDuration>(
     std::chrono::steady_clock::now() - this->ScriptStartTime);
diff --git a/Source/CTest/cmCTestScriptHandler.h b/Source/CTest/cmCTestScriptHandler.h
index ebb7905..8eb9658 100644
--- a/Source/CTest/cmCTestScriptHandler.h
+++ b/Source/CTest/cmCTestScriptHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestScriptHandler_h
-#define cmCTestScriptHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -176,5 +175,3 @@ private:
   std::unique_ptr<cmGlobalGenerator> GlobalGenerator;
   std::unique_ptr<cmake> CMake;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestSleepCommand.h b/Source/CTest/cmCTestSleepCommand.h
index 1c3b8a1..9425576 100644
--- a/Source/CTest/cmCTestSleepCommand.h
+++ b/Source/CTest/cmCTestSleepCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestSleepCommand_h
-#define cmCTestSleepCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -45,5 +44,3 @@ public:
   bool InitialPass(std::vector<std::string> const& args,
                    cmExecutionStatus& status) override;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestStartCommand.cxx b/Source/CTest/cmCTestStartCommand.cxx
index fe68406..53e1b2f 100644
--- a/Source/CTest/cmCTestStartCommand.cxx
+++ b/Source/CTest/cmCTestStartCommand.cxx
@@ -9,6 +9,7 @@
 #include "cmCTestVC.h"
 #include "cmGeneratedFileStream.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmSystemTools.h"
 
 class cmExecutionStatus;
@@ -29,8 +30,8 @@ bool cmCTestStartCommand::InitialPass(std::vector<std::string> const& args,
 
   size_t cnt = 0;
   const char* smodel = nullptr;
-  const char* src_dir = nullptr;
-  const char* bld_dir = nullptr;
+  const std::string* src_dir = nullptr;
+  const std::string* bld_dir = nullptr;
 
   while (cnt < args.size()) {
     if (args[cnt] == "GROUP" || args[cnt] == "TRACK") {
@@ -54,10 +55,10 @@ bool cmCTestStartCommand::InitialPass(std::vector<std::string> const& args,
       smodel = args[cnt].c_str();
       cnt++;
     } else if (!src_dir) {
-      src_dir = args[cnt].c_str();
+      src_dir = &args[cnt];
       cnt++;
     } else if (!bld_dir) {
-      bld_dir = args[cnt].c_str();
+      bld_dir = &args[cnt];
       cnt++;
     } else {
       this->SetError("Too many arguments");
@@ -87,32 +88,31 @@ bool cmCTestStartCommand::InitialPass(std::vector<std::string> const& args,
     return false;
   }
 
-  cmSystemTools::AddKeepPath(src_dir);
-  cmSystemTools::AddKeepPath(bld_dir);
+  cmSystemTools::AddKeepPath(*src_dir);
+  cmSystemTools::AddKeepPath(*bld_dir);
 
   this->CTest->EmptyCTestConfiguration();
 
-  std::string sourceDir = cmSystemTools::CollapseFullPath(src_dir);
-  std::string binaryDir = cmSystemTools::CollapseFullPath(bld_dir);
-  this->CTest->SetCTestConfiguration("SourceDirectory", sourceDir.c_str(),
-                                     this->Quiet);
-  this->CTest->SetCTestConfiguration("BuildDirectory", binaryDir.c_str(),
+  std::string sourceDir = cmSystemTools::CollapseFullPath(*src_dir);
+  std::string binaryDir = cmSystemTools::CollapseFullPath(*bld_dir);
+  this->CTest->SetCTestConfiguration("SourceDirectory", sourceDir,
                                      this->Quiet);
+  this->CTest->SetCTestConfiguration("BuildDirectory", binaryDir, this->Quiet);
 
   if (smodel) {
     cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
                        "Run dashboard with model "
                          << smodel << std::endl
-                         << "   Source directory: " << src_dir << std::endl
-                         << "   Build directory: " << bld_dir << std::endl,
+                         << "   Source directory: " << *src_dir << std::endl
+                         << "   Build directory: " << *bld_dir << std::endl,
                        this->Quiet);
   } else {
     cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
                        "Run dashboard with "
                        "to-be-determined model"
                          << std::endl
-                         << "   Source directory: " << src_dir << std::endl
-                         << "   Build directory: " << bld_dir << std::endl,
+                         << "   Source directory: " << *src_dir << std::endl
+                         << "   Build directory: " << *bld_dir << std::endl,
                        this->Quiet);
   }
   const char* group = this->CTest->GetSpecificGroup();
@@ -162,7 +162,7 @@ bool cmCTestStartCommand::InitialCheckout(std::ostream& ofs,
                                           std::string const& sourceDir)
 {
   // Use the user-provided command to create the source tree.
-  const char* initialCheckoutCommand =
+  cmProp initialCheckoutCommand =
     this->Makefile->GetDefinition("CTEST_CHECKOUT_COMMAND");
   if (!initialCheckoutCommand) {
     initialCheckoutCommand =
@@ -172,7 +172,7 @@ bool cmCTestStartCommand::InitialCheckout(std::ostream& ofs,
     // Use a generic VC object to run and log the command.
     cmCTestVC vc(this->CTest, ofs);
     vc.SetSourceDirectory(sourceDir);
-    if (!vc.InitialCheckout(initialCheckoutCommand)) {
+    if (!vc.InitialCheckout(*initialCheckoutCommand)) {
       return false;
     }
   }
diff --git a/Source/CTest/cmCTestStartCommand.h b/Source/CTest/cmCTestStartCommand.h
index b30b1bb..b3d06a7 100644
--- a/Source/CTest/cmCTestStartCommand.h
+++ b/Source/CTest/cmCTestStartCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestStartCommand_h
-#define cmCTestStartCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -62,5 +61,3 @@ private:
   bool CreateNewTag;
   bool Quiet;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestSubmitCommand.cxx b/Source/CTest/cmCTestSubmitCommand.cxx
index 279216e..bdba0e5 100644
--- a/Source/CTest/cmCTestSubmitCommand.cxx
+++ b/Source/CTest/cmCTestSubmitCommand.cxx
@@ -16,6 +16,7 @@
 #include "cmCommand.h"
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -35,12 +36,12 @@ std::unique_ptr<cmCommand> cmCTestSubmitCommand::Clone()
 
 cmCTestGenericHandler* cmCTestSubmitCommand::InitializeHandler()
 {
-  const char* submitURL = !this->SubmitURL.empty()
-    ? this->SubmitURL.c_str()
+  const std::string* submitURL = !this->SubmitURL.empty()
+    ? &this->SubmitURL
     : this->Makefile->GetDefinition("CTEST_SUBMIT_URL");
 
   if (submitURL) {
-    this->CTest->SetCTestConfiguration("SubmitURL", submitURL, this->Quiet);
+    this->CTest->SetCTestConfiguration("SubmitURL", *submitURL, this->Quiet);
   } else {
     this->CTest->SetCTestConfigurationFromCMakeVariable(
       this->Makefile, "DropMethod", "CTEST_DROP_METHOD", this->Quiet);
@@ -58,17 +59,17 @@ cmCTestGenericHandler* cmCTestSubmitCommand::InitializeHandler()
   this->CTest->SetCTestConfigurationFromCMakeVariable(
     this->Makefile, "CurlOptions", "CTEST_CURL_OPTIONS", this->Quiet);
 
-  const char* notesFilesVariable =
+  cmProp notesFilesVariable =
     this->Makefile->GetDefinition("CTEST_NOTES_FILES");
   if (notesFilesVariable) {
-    std::vector<std::string> notesFiles = cmExpandedList(notesFilesVariable);
+    std::vector<std::string> notesFiles = cmExpandedList(*notesFilesVariable);
     this->CTest->GenerateNotesFile(notesFiles);
   }
 
-  const char* extraFilesVariable =
+  cmProp extraFilesVariable =
     this->Makefile->GetDefinition("CTEST_EXTRA_SUBMIT_FILES");
   if (extraFilesVariable) {
-    std::vector<std::string> extraFiles = cmExpandedList(extraFilesVariable);
+    std::vector<std::string> extraFiles = cmExpandedList(*extraFilesVariable);
     if (!this->CTest->SubmitExtraFiles(extraFiles)) {
       this->SetError("problem submitting extra files.");
       return nullptr;
@@ -108,7 +109,7 @@ cmCTestGenericHandler* cmCTestSubmitCommand::InitializeHandler()
   if (this->PartsMentioned) {
     auto parts =
       cmMakeRange(this->Parts).transform([this](std::string const& arg) {
-        return this->CTest->GetPartFromName(arg.c_str());
+        return this->CTest->GetPartFromName(arg);
       });
     handler->SelectParts(std::set<cmCTest::Part>(parts.begin(), parts.end()));
   }
@@ -177,7 +178,7 @@ void cmCTestSubmitCommand::CheckArguments(
     !this->Files.empty() || cm::contains(keywords, "FILES");
 
   cm::erase_if(this->Parts, [this](std::string const& arg) -> bool {
-    cmCTest::Part p = this->CTest->GetPartFromName(arg.c_str());
+    cmCTest::Part p = this->CTest->GetPartFromName(arg);
     if (p == cmCTest::PartCount) {
       std::ostringstream e;
       e << "Part name \"" << arg << "\" is invalid.";
diff --git a/Source/CTest/cmCTestSubmitCommand.h b/Source/CTest/cmCTestSubmitCommand.h
index 9060771..c5d11df 100644
--- a/Source/CTest/cmCTestSubmitCommand.h
+++ b/Source/CTest/cmCTestSubmitCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestSubmitCommand_h
-#define cmCTestSubmitCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -55,5 +54,3 @@ protected:
   std::vector<std::string> HttpHeaders;
   std::vector<std::string> Parts;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestSubmitHandler.cxx b/Source/CTest/cmCTestSubmitHandler.cxx
index ea36df5..5b54573 100644
--- a/Source/CTest/cmCTestSubmitHandler.cxx
+++ b/Source/CTest/cmCTestSubmitHandler.cxx
@@ -797,7 +797,7 @@ int cmCTestSubmitHandler::ProcessHandler()
         gfile = gfile.substr(glen);
         cmCTestOptionalLog(this->CTest, DEBUG,
                            "Glob file: " << gfile << std::endl, this->Quiet);
-        this->CTest->AddSubmitFile(cmCTest::PartCoverage, gfile.c_str());
+        this->CTest->AddSubmitFile(cmCTest::PartCoverage, gfile);
       }
     } else {
       cmCTestLog(this->CTest, ERROR_MESSAGE, "Problem globbing" << std::endl);
diff --git a/Source/CTest/cmCTestSubmitHandler.h b/Source/CTest/cmCTestSubmitHandler.h
index 304daaa..809c615 100644
--- a/Source/CTest/cmCTestSubmitHandler.h
+++ b/Source/CTest/cmCTestSubmitHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestSubmitHandler_h
-#define cmCTestSubmitHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -77,5 +76,3 @@ private:
   std::set<std::string> Files;
   std::vector<std::string> HttpHeaders;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestTestCommand.cxx b/Source/CTest/cmCTestTestCommand.cxx
index c71b409..4403733 100644
--- a/Source/CTest/cmCTestTestCommand.cxx
+++ b/Source/CTest/cmCTestTestCommand.cxx
@@ -13,6 +13,7 @@
 #include "cmCTestTestHandler.h"
 #include "cmDuration.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 
 void cmCTestTestCommand::BindArguments()
@@ -39,12 +40,11 @@ void cmCTestTestCommand::BindArguments()
 
 cmCTestGenericHandler* cmCTestTestCommand::InitializeHandler()
 {
-  const char* ctestTimeout =
-    this->Makefile->GetDefinition("CTEST_TEST_TIMEOUT");
+  cmProp ctestTimeout = this->Makefile->GetDefinition("CTEST_TEST_TIMEOUT");
 
   cmDuration timeout;
   if (ctestTimeout) {
-    timeout = cmDuration(atof(ctestTimeout));
+    timeout = cmDuration(atof(ctestTimeout->c_str()));
   } else {
     timeout = this->CTest->GetTimeOut();
     if (timeout <= cmDuration::zero()) {
@@ -54,10 +54,10 @@ cmCTestGenericHandler* cmCTestTestCommand::InitializeHandler()
   }
   this->CTest->SetTimeOut(timeout);
 
-  const char* resourceSpecFile =
+  cmProp resourceSpecFile =
     this->Makefile->GetDefinition("CTEST_RESOURCE_SPEC_FILE");
   if (this->ResourceSpecFile.empty() && resourceSpecFile) {
-    this->ResourceSpecFile = resourceSpecFile;
+    this->ResourceSpecFile = *resourceSpecFile;
   }
 
   cmCTestGenericHandler* handler = this->InitializeActualHandler();
@@ -114,19 +114,19 @@ cmCTestGenericHandler* cmCTestTestCommand::InitializeHandler()
   // or CTEST_TEST_LOAD script variable, or ctest --test-load
   // command line argument... in that order.
   unsigned long testLoad;
-  const char* ctestTestLoad = this->Makefile->GetDefinition("CTEST_TEST_LOAD");
+  cmProp ctestTestLoad = this->Makefile->GetDefinition("CTEST_TEST_LOAD");
   if (!this->TestLoad.empty()) {
-    if (!cmStrToULong(this->TestLoad.c_str(), &testLoad)) {
+    if (!cmStrToULong(this->TestLoad, &testLoad)) {
       testLoad = 0;
       cmCTestLog(this->CTest, WARNING,
                  "Invalid value for 'TEST_LOAD' : " << this->TestLoad
                                                     << std::endl);
     }
-  } else if (ctestTestLoad && *ctestTestLoad) {
-    if (!cmStrToULong(ctestTestLoad, &testLoad)) {
+  } else if (cmNonempty(ctestTestLoad)) {
+    if (!cmStrToULong(*ctestTestLoad, &testLoad)) {
       testLoad = 0;
       cmCTestLog(this->CTest, WARNING,
-                 "Invalid value for 'CTEST_TEST_LOAD' : " << ctestTestLoad
+                 "Invalid value for 'CTEST_TEST_LOAD' : " << *ctestTestLoad
                                                           << std::endl);
     }
   } else {
@@ -134,10 +134,10 @@ cmCTestGenericHandler* cmCTestTestCommand::InitializeHandler()
   }
   handler->SetTestLoad(testLoad);
 
-  if (const char* labelsForSubprojects =
+  if (cmProp labelsForSubprojects =
         this->Makefile->GetDefinition("CTEST_LABELS_FOR_SUBPROJECTS")) {
     this->CTest->SetCTestConfiguration("LabelsForSubprojects",
-                                       labelsForSubprojects, this->Quiet);
+                                       *labelsForSubprojects, this->Quiet);
   }
 
   handler->SetQuiet(this->Quiet);
diff --git a/Source/CTest/cmCTestTestCommand.h b/Source/CTest/cmCTestTestCommand.h
index 7925586..624cd91 100644
--- a/Source/CTest/cmCTestTestCommand.h
+++ b/Source/CTest/cmCTestTestCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestTestCommand_h
-#define cmCTestTestCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -62,5 +61,3 @@ protected:
   std::string ResourceSpecFile;
   bool StopOnFailure = false;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestTestHandler.cxx b/Source/CTest/cmCTestTestHandler.cxx
index d0dbaae..4d1a589 100644
--- a/Source/CTest/cmCTestTestHandler.cxx
+++ b/Source/CTest/cmCTestTestHandler.cxx
@@ -37,6 +37,7 @@
 #include "cmGeneratedFileStream.h"
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStateSnapshot.h"
 #include "cmStringAlgorithms.h"
@@ -819,14 +820,16 @@ void cmCTestTestHandler::CheckLabelFilter(cmCTestTestProperties& it)
   this->CheckLabelFilterExclude(it);
 }
 
-void cmCTestTestHandler::ComputeTestList()
+bool cmCTestTestHandler::ComputeTestList()
 {
   this->TestList.clear(); // clear list of test
-  this->GetListOfTests();
+  if (!this->GetListOfTests()) {
+    return false;
+  }
 
   if (this->RerunFailed) {
     this->ComputeTestListForRerunFailed();
-    return;
+    return true;
   }
 
   cmCTestTestHandler::ListOfTests::size_type tmsize = this->TestList.size();
@@ -882,6 +885,7 @@ void cmCTestTestHandler::ComputeTestList()
   this->TestList = finalList;
 
   this->UpdateMaxTestNameWidth();
+  return true;
 }
 
 void cmCTestTestHandler::ComputeTestListForRerunFailed()
@@ -1260,7 +1264,10 @@ bool cmCTestTestHandler::GetValue(const char* tag, std::string& value,
 bool cmCTestTestHandler::ProcessDirectory(std::vector<std::string>& passed,
                                           std::vector<std::string>& failed)
 {
-  this->ComputeTestList();
+  if (!this->ComputeTestList()) {
+    return false;
+  }
+
   this->StartTest = this->CTest->CurrentTime();
   this->StartTestTime = std::chrono::system_clock::now();
   auto elapsed_time_start = std::chrono::steady_clock::now();
@@ -1374,7 +1381,7 @@ void cmCTestTestHandler::GenerateDartOutput(cmXMLWriter& xml)
   xml.StartElement("TestList");
   for (cmCTestTestResult const& result : this->TestResults) {
     std::string testPath = result.Path + "/" + result.Name;
-    xml.Element("Test", this->CTest->GetShortPathToFile(testPath.c_str()));
+    xml.Element("Test", this->CTest->GetShortPathToFile(testPath));
   }
   xml.EndElement(); // TestList
   for (cmCTestTestResult& result : this->TestResults) {
@@ -1483,8 +1490,8 @@ void cmCTestTestHandler::WriteTestResultHeader(cmXMLWriter& xml,
   }
   std::string testPath = result.Path + "/" + result.Name;
   xml.Element("Name", result.Name);
-  xml.Element("Path", this->CTest->GetShortPathToFile(result.Path.c_str()));
-  xml.Element("FullName", this->CTest->GetShortPathToFile(testPath.c_str()));
+  xml.Element("Path", this->CTest->GetShortPathToFile(result.Path));
+  xml.Element("FullName", this->CTest->GetShortPathToFile(testPath));
   xml.Element("FullCommandLine", result.FullCommandLine);
 }
 
@@ -1546,12 +1553,12 @@ int cmCTestTestHandler::ExecuteCommands(std::vector<std::string>& vec)
 }
 
 // Find the appropriate executable to run for a test
-std::string cmCTestTestHandler::FindTheExecutable(const char* exe)
+std::string cmCTestTestHandler::FindTheExecutable(const std::string& exe)
 {
   std::string resConfig;
   std::vector<std::string> extraPaths;
   std::vector<std::string> failedPaths;
-  if (strcmp(exe, "NOT_AVAILABLE") == 0) {
+  if (exe == "NOT_AVAILABLE") {
     return exe;
   }
   return cmCTestTestHandler::FindExecutable(this->CTest, exe, resConfig,
@@ -1607,7 +1614,7 @@ void cmCTestTestHandler::AddConfigurations(
 
 // Find the appropriate executable to run for a test
 std::string cmCTestTestHandler::FindExecutable(
-  cmCTest* ctest, const char* testCommand, std::string& resultingConfig,
+  cmCTest* ctest, const std::string& testCommand, std::string& resultingConfig,
   std::vector<std::string>& extraPaths, std::vector<std::string>& failed)
 {
   // now run the compiled test if we can find it
@@ -1695,7 +1702,7 @@ bool cmCTestTestHandler::ParseResourceGroupsProperty(
   return lexer.ParseString(val);
 }
 
-void cmCTestTestHandler::GetListOfTests()
+bool cmCTestTestHandler::GetListOfTests()
 {
   if (!this->IncludeLabelRegExp.empty()) {
     this->IncludeLabelRegularExpression.compile(
@@ -1748,22 +1755,24 @@ void cmCTestTestHandler::GetListOfTests()
     // does the DartTestfile.txt exist ?
     testFilename = "DartTestfile.txt";
   } else {
-    return;
+    return true;
   }
 
   if (!mf.ReadListFile(testFilename)) {
-    return;
+    return false;
   }
   if (cmSystemTools::GetErrorOccuredFlag()) {
-    return;
+    // SEND_ERROR or FATAL_ERROR in CTestTestfile or TEST_INCLUDE_FILES
+    return false;
   }
-  const char* specFile = mf.GetDefinition("CTEST_RESOURCE_SPEC_FILE");
+  cmProp specFile = mf.GetDefinition("CTEST_RESOURCE_SPEC_FILE");
   if (this->ResourceSpecFile.empty() && specFile) {
-    this->ResourceSpecFile = specFile;
+    this->ResourceSpecFile = *specFile;
   }
   cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT,
                      "Done constructing a list of tests" << std::endl,
                      this->Quiet);
+  return true;
 }
 
 void cmCTestTestHandler::UseIncludeRegExp()
diff --git a/Source/CTest/cmCTestTestHandler.h b/Source/CTest/cmCTestTestHandler.h
index 0d88c30..aa29eeb 100644
--- a/Source/CTest/cmCTestTestHandler.h
+++ b/Source/CTest/cmCTestTestHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestTestHandler_h
-#define cmCTestTestHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -198,7 +197,8 @@ public:
                                 std::string filepath, std::string& filename);
 
   // full signature static method to find an executable
-  static std::string FindExecutable(cmCTest* ctest, const char* testCommand,
+  static std::string FindExecutable(cmCTest* ctest,
+                                    const std::string& testCommand,
                                     std::string& resultingConfig,
                                     std::vector<std::string>& extraPaths,
                                     std::vector<std::string>& failed);
@@ -285,10 +285,10 @@ private:
   /**
    * Get the list of tests in directory and subdirectories.
    */
-  void GetListOfTests();
+  bool GetListOfTests();
   // compute the lists of tests that will actually run
   // based on union regex and -I stuff
-  void ComputeTestList();
+  bool ComputeTestList();
 
   // compute the lists of tests that will actually run
   // based on LastTestFailed.log
@@ -309,7 +309,7 @@ private:
   /**
    * Find the executable for a test
    */
-  std::string FindTheExecutable(const char* exe);
+  std::string FindTheExecutable(const std::string& exe);
 
   std::string GetTestStatus(cmCTestTestResult const&);
   void ExpandTestsToRunInformation(size_t numPossibleTests);
@@ -359,5 +359,3 @@ private:
   int RepeatCount = 1;
   bool RerunFailed;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestUpdateCommand.cxx b/Source/CTest/cmCTestUpdateCommand.cxx
index 673eb9a..6fef90a 100644
--- a/Source/CTest/cmCTestUpdateCommand.cxx
+++ b/Source/CTest/cmCTestUpdateCommand.cxx
@@ -5,20 +5,20 @@
 #include "cmCTest.h"
 #include "cmCTestUpdateHandler.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmSystemTools.h"
 
 cmCTestGenericHandler* cmCTestUpdateCommand::InitializeHandler()
 {
   if (!this->Source.empty()) {
     this->CTest->SetCTestConfiguration(
-      "SourceDirectory", cmSystemTools::CollapseFullPath(this->Source).c_str(),
+      "SourceDirectory", cmSystemTools::CollapseFullPath(this->Source),
       this->Quiet);
   } else {
     this->CTest->SetCTestConfiguration(
       "SourceDirectory",
       cmSystemTools::CollapseFullPath(
-        this->Makefile->GetDefinition("CTEST_SOURCE_DIRECTORY"))
-        .c_str(),
+        cmToCStrSafe(this->Makefile->GetDefinition("CTEST_SOURCE_DIRECTORY"))),
       this->Quiet);
   }
   std::string source_dir =
diff --git a/Source/CTest/cmCTestUpdateCommand.h b/Source/CTest/cmCTestUpdateCommand.h
index 5555c16..e4c3453 100644
--- a/Source/CTest/cmCTestUpdateCommand.h
+++ b/Source/CTest/cmCTestUpdateCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestUpdateCommand_h
-#define cmCTestUpdateCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -42,5 +41,3 @@ public:
 protected:
   cmCTestGenericHandler* InitializeHandler() override;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestUpdateHandler.h b/Source/CTest/cmCTestUpdateHandler.h
index afc0e3d..25bbb2f 100644
--- a/Source/CTest/cmCTestUpdateHandler.h
+++ b/Source/CTest/cmCTestUpdateHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestUpdateHandler_h
-#define cmCTestUpdateHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -63,5 +62,3 @@ private:
   int DetectVCS(const char* dir);
   bool SelectVCS();
 };
-
-#endif
diff --git a/Source/CTest/cmCTestUploadCommand.h b/Source/CTest/cmCTestUploadCommand.h
index 8334a9e..fe155f6 100644
--- a/Source/CTest/cmCTestUploadCommand.h
+++ b/Source/CTest/cmCTestUploadCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestUploadCommand_h
-#define cmCTestUploadCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -48,5 +47,3 @@ protected:
 
   std::vector<std::string> Files;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestUploadHandler.h b/Source/CTest/cmCTestUploadHandler.h
index dde14df..55d21c1 100644
--- a/Source/CTest/cmCTestUploadHandler.h
+++ b/Source/CTest/cmCTestUploadHandler.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestUploadHandler_h
-#define cmCTestUploadHandler_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -36,5 +35,3 @@ public:
 private:
   std::set<std::string> Files;
 };
-
-#endif
diff --git a/Source/CTest/cmCTestVC.h b/Source/CTest/cmCTestVC.h
index 3037e01..9bd7229 100644
--- a/Source/CTest/cmCTestVC.h
+++ b/Source/CTest/cmCTestVC.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTestVC_h
-#define cmCTestVC_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -150,5 +149,3 @@ protected:
   // Count paths reported with each PathStatus value.
   int PathCount[3];
 };
-
-#endif
diff --git a/Source/CTest/cmParseBlanketJSCoverage.h b/Source/CTest/cmParseBlanketJSCoverage.h
index cd1b225..e107454 100644
--- a/Source/CTest/cmParseBlanketJSCoverage.h
+++ b/Source/CTest/cmParseBlanketJSCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParseBlanketJSCoverage_h
-#define cmParseBlanketJSCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -39,4 +38,3 @@ protected:
   cmCTestCoverageHandlerContainer& Coverage;
   cmCTest* CTest;
 };
-#endif
diff --git a/Source/CTest/cmParseCacheCoverage.h b/Source/CTest/cmParseCacheCoverage.h
index a8200b7..523f83b 100644
--- a/Source/CTest/cmParseCacheCoverage.h
+++ b/Source/CTest/cmParseCacheCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParseCacheCoverage_h
-#define cmParseCacheCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -31,5 +30,3 @@ protected:
   // Read a single mcov file
   bool ReadCMCovFile(const char* f);
 };
-
-#endif
diff --git a/Source/CTest/cmParseCoberturaCoverage.h b/Source/CTest/cmParseCoberturaCoverage.h
index cb6d097..0340433 100644
--- a/Source/CTest/cmParseCoberturaCoverage.h
+++ b/Source/CTest/cmParseCoberturaCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParseCoberturaCoverage_h
-#define cmParseCoberturaCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -41,5 +40,3 @@ private:
   cmCTest* CTest;
   std::string CurFileName;
 };
-
-#endif
diff --git a/Source/CTest/cmParseDelphiCoverage.h b/Source/CTest/cmParseDelphiCoverage.h
index 1b37405..2a014a1 100644
--- a/Source/CTest/cmParseDelphiCoverage.h
+++ b/Source/CTest/cmParseDelphiCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParseDelphiCoverage_h
-#define cmParseDelphiCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -35,4 +34,3 @@ protected:
   cmCTestCoverageHandlerContainer& Coverage;
   cmCTest* CTest;
 };
-#endif
diff --git a/Source/CTest/cmParseGTMCoverage.h b/Source/CTest/cmParseGTMCoverage.h
index 41cc7f5..c35bf6e 100644
--- a/Source/CTest/cmParseGTMCoverage.h
+++ b/Source/CTest/cmParseGTMCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParseGTMCoverage_h
-#define cmParseGTMCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -37,5 +36,3 @@ protected:
   bool ParseMCOVLine(std::string const& line, std::string& routine,
                      std::string& function, int& linenumber, int& count);
 };
-
-#endif
diff --git a/Source/CTest/cmParseJacocoCoverage.h b/Source/CTest/cmParseJacocoCoverage.h
index f2aec6d..3442dd0 100644
--- a/Source/CTest/cmParseJacocoCoverage.h
+++ b/Source/CTest/cmParseJacocoCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParseJacocoCoverage_h
-#define cmParseJacocoCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -49,5 +48,3 @@ private:
   cmCTestCoverageHandlerContainer& Coverage;
   cmCTest* CTest;
 };
-
-#endif
diff --git a/Source/CTest/cmParseMumpsCoverage.h b/Source/CTest/cmParseMumpsCoverage.h
index 8c08702..00a8431 100644
--- a/Source/CTest/cmParseMumpsCoverage.h
+++ b/Source/CTest/cmParseMumpsCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParseMumpsCoverage_h
-#define cmParseMumpsCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -43,5 +42,3 @@ protected:
   cmCTestCoverageHandlerContainer& Coverage;
   cmCTest* CTest;
 };
-
-#endif
diff --git a/Source/CTest/cmParsePHPCoverage.h b/Source/CTest/cmParsePHPCoverage.h
index ff0e636..763a6bb 100644
--- a/Source/CTest/cmParsePHPCoverage.h
+++ b/Source/CTest/cmParsePHPCoverage.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmParsePHPCoverage_h
-#define cmParsePHPCoverage_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -35,5 +34,3 @@ private:
   cmCTestCoverageHandlerContainer& Coverage;
   cmCTest* CTest;
 };
-
-#endif
diff --git a/Source/CTest/cmProcess.cxx b/Source/CTest/cmProcess.cxx
index a549117..9ee1c17 100644
--- a/Source/CTest/cmProcess.cxx
+++ b/Source/CTest/cmProcess.cxx
@@ -545,17 +545,17 @@ std::string cmProcess::GetExitExceptionString()
 #  endif
 #  ifdef SIGABRT
     case SIGABRT:
-      exception_str = "Child aborted";
+      exception_str = "Subprocess aborted";
       break;
 #  endif
 #  ifdef SIGKILL
     case SIGKILL:
-      exception_str = "Child killed";
+      exception_str = "Subprocess killed";
       break;
 #  endif
 #  ifdef SIGTERM
     case SIGTERM:
-      exception_str = "Child terminated";
+      exception_str = "Subprocess terminated";
       break;
 #  endif
 #  ifdef SIGHUP
diff --git a/Source/CTest/cmProcess.h b/Source/CTest/cmProcess.h
index 1e6578c..9eec952 100644
--- a/Source/CTest/cmProcess.h
+++ b/Source/CTest/cmProcess.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmProcess_h
-#define cmProcess_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -132,5 +131,3 @@ private:
   int Id;
   int64_t ExitValue;
 };
-
-#endif
diff --git a/Source/Checks/cm_cxx_features.cmake b/Source/Checks/cm_cxx_features.cmake
index 50ccc7c..5c1593d 100644
--- a/Source/Checks/cm_cxx_features.cmake
+++ b/Source/Checks/cm_cxx_features.cmake
@@ -1,6 +1,7 @@
 include(${CMAKE_CURRENT_LIST_DIR}/cm_message_checks_compat.cmake)
 
 function(cm_check_cxx_feature name)
+  set(TRY_RUN_FEATURE "${ARGN}")
   string(TOUPPER ${name} FEATURE)
   if(NOT DEFINED CMake_HAVE_CXX_${FEATURE})
     cm_message_checks_compat(
@@ -12,12 +13,26 @@ function(cm_check_cxx_feature name)
     else()
       set(maybe_cxx_standard "")
     endif()
-    try_compile(CMake_HAVE_CXX_${FEATURE}
-      ${CMAKE_CURRENT_BINARY_DIR}
-      ${CMAKE_CURRENT_LIST_DIR}/cm_cxx_${name}.cxx
-      CMAKE_FLAGS ${maybe_cxx_standard}
-      OUTPUT_VARIABLE OUTPUT
-      )
+    if (TRY_RUN_FEATURE)
+      try_run(CMake_RUN_CXX_${FEATURE} CMake_COMPILE_CXX_${FEATURE}
+        ${CMAKE_CURRENT_BINARY_DIR}
+        ${CMAKE_CURRENT_LIST_DIR}/cm_cxx_${name}.cxx
+        CMAKE_FLAGS ${maybe_cxx_standard}
+        OUTPUT_VARIABLE OUTPUT
+        )
+      if (CMake_RUN_CXX_${FEATURE} EQUAL "0" AND CMake_COMPILE_CXX_${FEATURE})
+        set(CMake_HAVE_CXX_${FEATURE} ON CACHE INTERNAL "TRY_RUN" FORCE)
+      else()
+        set(CMake_HAVE_CXX_${FEATURE} OFF CACHE INTERNAL "TRY_RUN" FORCE)
+      endif()
+    else()
+      try_compile(CMake_HAVE_CXX_${FEATURE}
+        ${CMAKE_CURRENT_BINARY_DIR}
+        ${CMAKE_CURRENT_LIST_DIR}/cm_cxx_${name}.cxx
+        CMAKE_FLAGS ${maybe_cxx_standard}
+        OUTPUT_VARIABLE OUTPUT
+        )
+    endif()
     set(check_output "${OUTPUT}")
     # Filter out MSBuild output that looks like a warning.
     string(REGEX REPLACE " +0 Warning\\(s\\)" "" check_output "${check_output}")
@@ -63,3 +78,8 @@ if(CMake_HAVE_CXX_MAKE_UNIQUE)
   set(CMake_HAVE_CXX_UNIQUE_PTR 1)
 endif()
 cm_check_cxx_feature(unique_ptr)
+if (NOT CMAKE_CXX_STANDARD LESS "17")
+  cm_check_cxx_feature(filesystem TRY_RUN)
+else()
+  set(CMake_HAVE_CXX_FILESYSTEM FALSE)
+endif()
diff --git a/Source/Checks/cm_cxx_filesystem.cxx b/Source/Checks/cm_cxx_filesystem.cxx
new file mode 100644
index 0000000..ae8acc5
--- /dev/null
+++ b/Source/Checks/cm_cxx_filesystem.cxx
@@ -0,0 +1,27 @@
+
+#include <filesystem>
+
+int main()
+{
+  std::filesystem::path p0(L"/a/b/c");
+
+  std::filesystem::path p1("/a/b/c");
+  std::filesystem::path p2("/a/b/c");
+  if (p1 != p2) {
+    return 1;
+  }
+
+#if defined(_WIN32)
+  std::filesystem::path p3("//host/a/b/../c");
+  if (p3.lexically_normal().generic_string() != "//host/a/c") {
+    return 1;
+  }
+
+  std::filesystem::path p4("c://a/.///b/../");
+  if (p4.lexically_normal().generic_string() != "c:/a/") {
+    return 1;
+  }
+#endif
+
+  return 0;
+}
diff --git a/Source/CursesDialog/ccmake.cxx b/Source/CursesDialog/ccmake.cxx
index 9a26db5..85e256b 100644
--- a/Source/CursesDialog/ccmake.cxx
+++ b/Source/CursesDialog/ccmake.cxx
@@ -2,11 +2,15 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
 #include <csignal>
+#include <cstdio>
+#include <cstdlib>
 #include <cstring>
 #include <iostream>
 #include <string>
 #include <vector>
 
+#include <unistd.h>
+
 #include "cmsys/Encoding.hxx"
 
 #include "cmCursesColor.h"
@@ -54,7 +58,12 @@ void onsig(int /*unused*/)
 {
   if (cmCursesForm::CurrentForm) {
     endwin();
-    initscr();            /* Initialization */
+    if (initscr() == nullptr) {
+      static const char errmsg[] = "Error: ncurses initialization failed\n";
+      auto r = write(STDERR_FILENO, errmsg, sizeof(errmsg) - 1);
+      static_cast<void>(r);
+      exit(1);
+    }
     noecho();             /* Echo off */
     cbreak();             /* nl- or cr not needed */
     keypad(stdscr, true); /* Use key symbols as KEY_DOWN */
@@ -124,7 +133,10 @@ int main(int argc, char const* const* argv)
     cmCursesForm::DebugStart();
   }
 
-  initscr();            /* Initialization */
+  if (initscr() == nullptr) {
+    fprintf(stderr, "Error: ncurses initialization failed\n");
+    exit(1);
+  }
   noecho();             /* Echo off */
   cbreak();             /* nl- or cr not needed */
   keypad(stdscr, true); /* Use key symbols as KEY_DOWN */
diff --git a/Source/CursesDialog/cmCursesBoolWidget.h b/Source/CursesDialog/cmCursesBoolWidget.h
index 8c96256..746825b 100644
--- a/Source/CursesDialog/cmCursesBoolWidget.h
+++ b/Source/CursesDialog/cmCursesBoolWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesBoolWidget_h
-#define cmCursesBoolWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -29,5 +28,3 @@ public:
   void SetValueAsBool(bool value);
   bool GetValueAsBool();
 };
-
-#endif // cmCursesBoolWidget_h
diff --git a/Source/CursesDialog/cmCursesCacheEntryComposite.h b/Source/CursesDialog/cmCursesCacheEntryComposite.h
index a711363..d414918 100644
--- a/Source/CursesDialog/cmCursesCacheEntryComposite.h
+++ b/Source/CursesDialog/cmCursesCacheEntryComposite.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesCacheEntryComposite_h
-#define cmCursesCacheEntryComposite_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -41,5 +40,3 @@ protected:
   int LabelWidth;
   int EntryWidth;
 };
-
-#endif // cmCursesCacheEntryComposite_h
diff --git a/Source/CursesDialog/cmCursesColor.h b/Source/CursesDialog/cmCursesColor.h
index f83265f..4e8a1e4 100644
--- a/Source/CursesDialog/cmCursesColor.h
+++ b/Source/CursesDialog/cmCursesColor.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesColor_h
-#define cmCursesColor_h
+#pragma once
 
 class cmCursesColor
 {
@@ -23,5 +22,3 @@ public:
 protected:
   static short GetColor(char id, short fallback);
 };
-
-#endif // cmCursesColor_h
diff --git a/Source/CursesDialog/cmCursesDummyWidget.h b/Source/CursesDialog/cmCursesDummyWidget.h
index 07b7288..4347746 100644
--- a/Source/CursesDialog/cmCursesDummyWidget.h
+++ b/Source/CursesDialog/cmCursesDummyWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesDummyWidget_h
-#define cmCursesDummyWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -24,5 +23,3 @@ public:
   // handled.
   bool HandleInput(int& key, cmCursesMainForm* fm, WINDOW* w) override;
 };
-
-#endif // cmCursesDummyWidget_h
diff --git a/Source/CursesDialog/cmCursesFilePathWidget.h b/Source/CursesDialog/cmCursesFilePathWidget.h
index 3f71259..2ae5d14 100644
--- a/Source/CursesDialog/cmCursesFilePathWidget.h
+++ b/Source/CursesDialog/cmCursesFilePathWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesFilePathWidget_h
-#define cmCursesFilePathWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -15,5 +14,3 @@ public:
   cmCursesFilePathWidget(cmCursesFilePathWidget const&) = delete;
   cmCursesFilePathWidget& operator=(cmCursesFilePathWidget const&) = delete;
 };
-
-#endif // cmCursesFilePathWidget_h
diff --git a/Source/CursesDialog/cmCursesForm.h b/Source/CursesDialog/cmCursesForm.h
index e3626e6..93459b9 100644
--- a/Source/CursesDialog/cmCursesForm.h
+++ b/Source/CursesDialog/cmCursesForm.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesForm_h
-#define cmCursesForm_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -62,5 +61,3 @@ protected:
 
   FORM* Form;
 };
-
-#endif // cmCursesForm_h
diff --git a/Source/CursesDialog/cmCursesLabelWidget.h b/Source/CursesDialog/cmCursesLabelWidget.h
index 9e75681..c10aa37 100644
--- a/Source/CursesDialog/cmCursesLabelWidget.h
+++ b/Source/CursesDialog/cmCursesLabelWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesLabelWidget_h
-#define cmCursesLabelWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -28,5 +27,3 @@ public:
   // handled
   bool HandleInput(int& key, cmCursesMainForm* fm, WINDOW* w) override;
 };
-
-#endif // cmCursesLabelWidget_h
diff --git a/Source/CursesDialog/cmCursesLongMessageForm.h b/Source/CursesDialog/cmCursesLongMessageForm.h
index da9fea2..4f69cb1 100644
--- a/Source/CursesDialog/cmCursesLongMessageForm.h
+++ b/Source/CursesDialog/cmCursesLongMessageForm.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesLongMessageForm_h
-#define cmCursesLongMessageForm_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -59,5 +58,3 @@ protected:
 
   FIELD* Fields[2];
 };
-
-#endif // cmCursesLongMessageForm_h
diff --git a/Source/CursesDialog/cmCursesMainForm.h b/Source/CursesDialog/cmCursesMainForm.h
index 2e06b90..c6db66f 100644
--- a/Source/CursesDialog/cmCursesMainForm.h
+++ b/Source/CursesDialog/cmCursesMainForm.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesMainForm_h
-#define cmCursesMainForm_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -170,5 +169,3 @@ protected:
   std::string OldSearchString;
   bool SearchMode;
 };
-
-#endif // cmCursesMainForm_h
diff --git a/Source/CursesDialog/cmCursesOptionsWidget.h b/Source/CursesDialog/cmCursesOptionsWidget.h
index 0de8e64..cb06e4d 100644
--- a/Source/CursesDialog/cmCursesOptionsWidget.h
+++ b/Source/CursesDialog/cmCursesOptionsWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesOptionsWidget_h
-#define cmCursesOptionsWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -35,5 +34,3 @@ protected:
   std::vector<std::string> Options;
   std::vector<std::string>::size_type CurrentOption;
 };
-
-#endif // cmCursesOptionsWidget_h
diff --git a/Source/CursesDialog/cmCursesPathWidget.h b/Source/CursesDialog/cmCursesPathWidget.h
index fb365e9..79e342e 100644
--- a/Source/CursesDialog/cmCursesPathWidget.h
+++ b/Source/CursesDialog/cmCursesPathWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesPathWidget_h
-#define cmCursesPathWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -34,5 +33,3 @@ protected:
   bool Cycle;
   std::string::size_type CurrentIndex;
 };
-
-#endif // cmCursesPathWidget_h
diff --git a/Source/CursesDialog/cmCursesStandardIncludes.h b/Source/CursesDialog/cmCursesStandardIncludes.h
index 5b0ad58..9745b97 100644
--- a/Source/CursesDialog/cmCursesStandardIncludes.h
+++ b/Source/CursesDialog/cmCursesStandardIncludes.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesStandardIncludes_h
-#define cmCursesStandardIncludes_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -41,5 +40,3 @@ inline void curses_clear()
 #  undef __attribute__
 #endif
 #undef cm_no__attribute__
-
-#endif // cmCursesStandardIncludes_h
diff --git a/Source/CursesDialog/cmCursesStringWidget.h b/Source/CursesDialog/cmCursesStringWidget.h
index ce06c6d..faa2ade 100644
--- a/Source/CursesDialog/cmCursesStringWidget.h
+++ b/Source/CursesDialog/cmCursesStringWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesStringWidget_h
-#define cmCursesStringWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -65,5 +64,3 @@ protected:
   std::string OriginalString;
   bool Done;
 };
-
-#endif // cmCursesStringWidget_h
diff --git a/Source/CursesDialog/cmCursesWidget.h b/Source/CursesDialog/cmCursesWidget.h
index 9d03c6e..29ec28b 100644
--- a/Source/CursesDialog/cmCursesWidget.h
+++ b/Source/CursesDialog/cmCursesWidget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCursesWidget_h
-#define cmCursesWidget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -68,5 +67,3 @@ protected:
   // The page in the main form this widget is in
   int Page;
 };
-
-#endif // cmCursesWidget_h
diff --git a/Source/CursesDialog/form/CMakeLists.txt b/Source/CursesDialog/form/CMakeLists.txt
index b468f5b..21c499e 100644
--- a/Source/CursesDialog/form/CMakeLists.txt
+++ b/Source/CursesDialog/form/CMakeLists.txt
@@ -3,6 +3,14 @@
 
 project(CMAKE_FORM)
 
+# Disable warnings to avoid changing 3rd party code.
+if(CMAKE_C_COMPILER_ID MATCHES
+    "^(GNU|Clang|AppleClang|XLClang|XL|VisualAge|SunPro|HP|Intel)$")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -w")
+elseif(CMAKE_C_COMPILER_ID STREQUAL "PathScale")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -woffall")
+endif()
+
 configure_file(cmFormConfigure.h.in "${CMAKE_CURRENT_BINARY_DIR}/cmFormConfigure.h")
 
 add_library(cmForm
diff --git a/Source/CursesDialog/form/frm_driver.c b/Source/CursesDialog/form/frm_driver.c
index e4e72aa..112ab08 100644
--- a/Source/CursesDialog/form/frm_driver.c
+++ b/Source/CursesDialog/form/frm_driver.c
@@ -2983,7 +2983,7 @@ INLINE static FIELD *Right_Neighbour_Field(FIELD * field)
 |   Function      :  static FIELD *Upper_Neighbour_Field(FIELD * field)
 |   
 |   Description   :  Because of the row-major nature of sorting the fields,
-|                    its more difficult to define whats the upper neighbour
+|                    its more difficult to define what's the upper neighbour
 |                    field really means. We define that it must be on a
 |                    'previous' line (cyclic order!) and is the rightmost
 |                    field laying on the left side of the given field. If
@@ -3030,7 +3030,7 @@ static FIELD *Upper_Neighbour_Field(FIELD * field)
 |   Function      :  static FIELD *Down_Neighbour_Field(FIELD * field)
 |   
 |   Description   :  Because of the row-major nature of sorting the fields,
-|                    its more difficult to define whats the down neighbour
+|                    its more difficult to define what's the down neighbour
 |                    field really means. We define that it must be on a
 |                    'next' line (cyclic order!) and is the leftmost
 |                    field laying on the right side of the given field. If
diff --git a/Source/QtDialog/AddCacheEntry.h b/Source/QtDialog/AddCacheEntry.h
index e7a60dd..35522c5 100644
--- a/Source/QtDialog/AddCacheEntry.h
+++ b/Source/QtDialog/AddCacheEntry.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef AddCacheEntry_h
-#define AddCacheEntry_h
+#pragma once
 
 #include "QCMake.h"
 #include <QCheckBox>
@@ -32,5 +31,3 @@ private:
   const QStringList& VarNames;
   const QStringList& VarTypes;
 };
-
-#endif
diff --git a/Source/QtDialog/CMakeLists.txt b/Source/QtDialog/CMakeLists.txt
index 98dd0e2..e6d6b17 100644
--- a/Source/QtDialog/CMakeLists.txt
+++ b/Source/QtDialog/CMakeLists.txt
@@ -3,111 +3,79 @@
 
 project(QtDialog)
 CMake_OPTIONAL_COMPONENT(cmake-gui)
-find_package(Qt5Widgets QUIET)
-if (Qt5Widgets_FOUND)
-  include_directories(${Qt5Widgets_INCLUDE_DIRS})
-  add_definitions(${Qt5Widgets_DEFINITONS})
-  macro(qt4_wrap_ui)
-    qt5_wrap_ui(${ARGN})
-  endmacro()
-  macro(qt4_wrap_cpp)
-    qt5_wrap_cpp(${ARGN})
-  endmacro()
-  macro(qt4_add_resources)
-    qt5_add_resources(${ARGN})
-  endmacro()
+find_package(Qt5Widgets REQUIRED)
 
-  set(CMake_QT_LIBRARIES ${Qt5Widgets_LIBRARIES})
-  set(QT_QTMAIN_LIBRARY ${Qt5Core_QTMAIN_LIBRARIES})
+set(CMake_QT_EXTRA_LIBRARIES)
 
-  # Try to find the package WinExtras for the task bar progress
-  if(WIN32)
-    find_package(Qt5WinExtras QUIET)
-    if (Qt5WinExtras_FOUND)
-      include_directories(${Qt5WinExtras_INCLUDE_DIRS})
-      add_definitions(-DQT_WINEXTRAS)
-      list(APPEND CMake_QT_LIBRARIES ${Qt5WinExtras_LIBRARIES})
-    endif()
+# Try to find the package WinExtras for the task bar progress
+if(WIN32)
+  find_package(Qt5WinExtras QUIET)
+  if (Qt5WinExtras_FOUND)
+    add_definitions(-DQT_WINEXTRAS)
+    list(APPEND CMake_QT_EXTRA_LIBRARIES Qt5::WinExtras)
   endif()
+endif()
 
-  # Remove this when the minimum version of Qt is 4.6.
-  add_definitions(-DQT_DISABLE_DEPRECATED_BEFORE=0)
-
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${Qt5Widgets_EXECUTABLE_COMPILE_FLAGS}")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${Qt5Widgets_EXECUTABLE_COMPILE_FLAGS}")
 
-  if(CMake_QT_STATIC_QXcbIntegrationPlugin_LIBRARIES)
-    list(APPEND CMake_QT_LIBRARIES ${CMake_QT_STATIC_QXcbIntegrationPlugin_LIBRARIES})
-    set_property(SOURCE CMakeSetup.cxx
-      PROPERTY COMPILE_DEFINITIONS USE_QXcbIntegrationPlugin)
-  endif()
+if(CMake_QT_STATIC_QXcbIntegrationPlugin_LIBRARIES)
+  list(APPEND CMake_QT_EXTRA_LIBRARIES ${CMake_QT_STATIC_QXcbIntegrationPlugin_LIBRARIES})
+  set_property(SOURCE CMakeSetup.cxx
+    PROPERTY COMPILE_DEFINITIONS USE_QXcbIntegrationPlugin)
+endif()
 
-  if(CMake_QT_STATIC_QWindowsIntegrationPlugin_LIBRARIES)
-    list(APPEND CMake_QT_LIBRARIES ${CMake_QT_STATIC_QWindowsIntegrationPlugin_LIBRARIES})
-    set_property(SOURCE CMakeSetup.cxx
-      PROPERTY COMPILE_DEFINITIONS USE_QWindowsIntegrationPlugin)
-  endif()
+if(CMake_QT_STATIC_QWindowsIntegrationPlugin_LIBRARIES)
+  list(APPEND CMake_QT_EXTRA_LIBRARIES ${CMake_QT_STATIC_QWindowsIntegrationPlugin_LIBRARIES})
+  set_property(SOURCE CMakeSetup.cxx
+    PROPERTY COMPILE_DEFINITIONS USE_QWindowsIntegrationPlugin)
+endif()
 
-  # We need to install platform plugin and add qt.conf for Qt5 on Mac and Windows.
-  # FIXME: This should be part of Qt5 CMake scripts, but unfortunately
-  # Qt5 support is missing there.
-  if(CMake_INSTALL_DEPENDENCIES AND (APPLE OR WIN32))
-    macro(install_qt5_plugin _qt_plugin_name _qt_plugins_var)
-      get_target_property(_qt_plugin_path "${_qt_plugin_name}" LOCATION)
-      if(EXISTS "${_qt_plugin_path}")
-        get_filename_component(_qt_plugin_file "${_qt_plugin_path}" NAME)
-        get_filename_component(_qt_plugin_type "${_qt_plugin_path}" PATH)
-        get_filename_component(_qt_plugin_type "${_qt_plugin_type}" NAME)
-        if(APPLE)
-          set(_qt_plugin_dir "PlugIns")
-        elseif(WIN32)
-          set(_qt_plugin_dir "plugins")
-        endif()
-        set(_qt_plugin_dest "${_qt_plugin_dir}/${_qt_plugin_type}")
-        install(FILES "${_qt_plugin_path}"
-          DESTINATION "${_qt_plugin_dest}"
-          ${COMPONENT})
-        set(${_qt_plugins_var}
-          "${${_qt_plugins_var}};\$ENV{DESTDIR}\${CMAKE_INSTALL_PREFIX}/${_qt_plugin_dest}/${_qt_plugin_file}")
-      else()
-        message(FATAL_ERROR "QT plugin ${_qt_plugin_name} not found")
+# We need to install platform plugin and add qt.conf for Qt5 on Mac and Windows.
+# FIXME: This should be part of Qt5 CMake scripts, but unfortunately
+# Qt5 support is missing there.
+if(CMake_INSTALL_DEPENDENCIES AND (APPLE OR WIN32))
+  macro(install_qt5_plugin _qt_plugin_name _qt_plugins_var)
+    get_target_property(_qt_plugin_path "${_qt_plugin_name}" LOCATION)
+    if(EXISTS "${_qt_plugin_path}")
+      get_filename_component(_qt_plugin_file "${_qt_plugin_path}" NAME)
+      get_filename_component(_qt_plugin_type "${_qt_plugin_path}" PATH)
+      get_filename_component(_qt_plugin_type "${_qt_plugin_type}" NAME)
+      if(APPLE)
+        set(_qt_plugin_dir "PlugIns")
+      elseif(WIN32)
+        set(_qt_plugin_dir "plugins")
       endif()
-    endmacro()
-    if(APPLE)
-      install_qt5_plugin("Qt5::QCocoaIntegrationPlugin" QT_PLUGINS)
-      file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
-        "[Paths]\nPlugins = ${_qt_plugin_dir}\n")
-      install(FILES "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
-        DESTINATION "${CMAKE_INSTALL_PREFIX}/Resources"
+      set(_qt_plugin_dest "${_qt_plugin_dir}/${_qt_plugin_type}")
+      install(FILES "${_qt_plugin_path}"
+        DESTINATION "${_qt_plugin_dest}"
         ${COMPONENT})
-    elseif(WIN32 AND NOT CMake_QT_STATIC_QWindowsIntegrationPlugin_LIBRARIES)
-      install_qt5_plugin("Qt5::QWindowsIntegrationPlugin" QT_PLUGINS)
-      file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
-        "[Paths]\nPlugins = ../${_qt_plugin_dir}\n")
-      install(FILES "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
-        DESTINATION bin
-        ${COMPONENT})
-    endif()
-  endif()
-
-  if(TARGET Qt5::Core)
-    get_property(_Qt5_Core_LOCATION TARGET Qt5::Core PROPERTY LOCATION)
-    get_filename_component(Qt_BIN_DIR "${_Qt5_Core_LOCATION}" PATH)
-    if(APPLE)
-      get_filename_component(Qt_BIN_DIR "${Qt_BIN_DIR}" PATH)
+      set(${_qt_plugins_var}
+        "${${_qt_plugins_var}};\$ENV{DESTDIR}\${CMAKE_INSTALL_PREFIX}/${_qt_plugin_dest}/${_qt_plugin_file}")
+    else()
+      message(FATAL_ERROR "QT plugin ${_qt_plugin_name} not found")
     endif()
+  endmacro()
+  if(APPLE)
+    install_qt5_plugin("Qt5::QCocoaIntegrationPlugin" QT_PLUGINS)
+    file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
+      "[Paths]\nPlugins = ${_qt_plugin_dir}\n")
+    install(FILES "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
+      DESTINATION "${CMAKE_INSTALL_PREFIX}/Resources"
+      ${COMPONENT})
+  elseif(WIN32 AND NOT CMake_QT_STATIC_QWindowsIntegrationPlugin_LIBRARIES)
+    install_qt5_plugin("Qt5::QWindowsIntegrationPlugin" QT_PLUGINS)
+    file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
+      "[Paths]\nPlugins = ../${_qt_plugin_dir}\n")
+    install(FILES "${CMAKE_CURRENT_BINARY_DIR}/qt.conf"
+      DESTINATION bin
+      ${COMPONENT})
   endif()
-else()
-  set(QT_MIN_VERSION "4.4.0")
-  find_package(Qt4 REQUIRED)
-  if(NOT QT4_FOUND)
-    message(SEND_ERROR "Failed to find Qt 4.4 or greater.")
-    return()
-  endif()
-
-  include(${QT_USE_FILE})
-
-  set(CMake_QT_LIBRARIES ${QT_LIBRARIES})
+endif()
 
+get_property(_Qt5_Core_LOCATION TARGET Qt5::Core PROPERTY LOCATION)
+get_filename_component(Qt_BIN_DIR "${_Qt5_Core_LOCATION}" PATH)
+if(APPLE)
+  get_filename_component(Qt_BIN_DIR "${Qt_BIN_DIR}" PATH)
 endif()
 
 set(SRCS
@@ -116,6 +84,7 @@ set(SRCS
   CMakeSetup.cxx
   CMakeSetupDialog.cxx
   CMakeSetupDialog.h
+  Compilers.h
   FirstConfigure.cxx
   FirstConfigure.h
   QCMake.cxx
@@ -129,7 +98,7 @@ set(SRCS
   WarningMessagesDialog.cxx
   WarningMessagesDialog.h
   )
-QT4_WRAP_UI(UI_SRCS
+qt5_wrap_ui(UI_SRCS
   CMakeSetupDialog.ui
   Compilers.ui
   CrossCompiler.ui
@@ -137,7 +106,7 @@ QT4_WRAP_UI(UI_SRCS
   RegexExplorer.ui
   WarningMessagesDialog.ui
   )
-QT4_WRAP_CPP(MOC_SRCS
+qt5_wrap_cpp(MOC_SRCS
   AddCacheEntry.h
   Compilers.h
   CMakeSetupDialog.h
@@ -148,14 +117,24 @@ QT4_WRAP_CPP(MOC_SRCS
   RegexExplorer.h
   WarningMessagesDialog.h
   )
-QT4_ADD_RESOURCES(RC_SRCS CMakeSetup.qrc)
+qt5_add_resources(RC_SRCS CMakeSetup.qrc)
+
+if (FALSE) # CMake's bootstrap binary does not support automoc
+  set(CMAKE_AUTOMOC 1)
+  set(CMAKE_AUTORCC 1)
+  set(CMAKE_AUTOUIC 1)
+else ()
+  list(APPEND SRCS
+    ${UI_SRCS}
+    ${MOC_SRCS}
+    ${RC_SRCS})
+endif ()
 
-set(SRCS ${SRCS} ${UI_SRCS} ${MOC_SRCS} ${RC_SRCS})
 if(WIN32)
-  set(SRCS ${SRCS} CMakeSetup.rc)
+  list(APPEND SRCS CMakeSetup.rc)
 endif()
 if(APPLE)
-  set(SRCS ${SRCS} CMakeSetup.icns)
+  list(APPEND SRCS CMakeSetup.icns)
   set(MACOSX_BUNDLE_ICON_FILE CMakeSetup.icns)
   set_source_files_properties(CMakeSetup.icns PROPERTIES
     MACOSX_PACKAGE_LOCATION Resources)
@@ -172,7 +151,7 @@ endif()
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 
 add_executable(cmake-gui WIN32 MACOSX_BUNDLE ${SRCS} ${MANIFEST_FILE})
-target_link_libraries(cmake-gui CMakeLib ${QT_QTMAIN_LIBRARY} ${CMake_QT_LIBRARIES})
+target_link_libraries(cmake-gui CMakeLib Qt5::Core Qt5::Widgets ${CMake_QT_EXTRA_LIBRARIES})
 
 if(WIN32)
   target_sources(cmake-gui PRIVATE $<TARGET_OBJECTS:CMakeVersion>)
diff --git a/Source/QtDialog/CMakeSetup.cxx b/Source/QtDialog/CMakeSetup.cxx
index 9d928b2..7ef5a72 100644
--- a/Source/QtDialog/CMakeSetup.cxx
+++ b/Source/QtDialog/CMakeSetup.cxx
@@ -115,14 +115,6 @@ int main(int argc, char** argv)
   QTextCodec* utf8_codec = QTextCodec::codecForName("UTF-8");
   QTextCodec::setCodecForLocale(utf8_codec);
 
-#if QT_VERSION < 0x050000
-  // clean out standard Qt paths for plugins, which we don't use anyway
-  // when creating Mac bundles, it potentially causes problems
-  foreach (QString p, QApplication::libraryPaths()) {
-    QApplication::removeLibraryPath(p);
-  }
-#endif
-
   // tell the cmake library where cmake is
   QDir cmExecDir(QApplication::applicationDirPath());
 #if defined(Q_OS_MAC)
diff --git a/Source/QtDialog/CMakeSetupDialog.cxx b/Source/QtDialog/CMakeSetupDialog.cxx
index 6dbfe11..fcc8408 100644
--- a/Source/QtDialog/CMakeSetupDialog.cxx
+++ b/Source/QtDialog/CMakeSetupDialog.cxx
@@ -152,9 +152,6 @@ CMakeSetupDialog::CMakeSetupDialog()
   this->WarnUninitializedAction =
     OptionsMenu->addAction(tr("&Warn Uninitialized (--warn-uninitialized)"));
   this->WarnUninitializedAction->setCheckable(true);
-  this->WarnUnusedAction =
-    OptionsMenu->addAction(tr("&Warn Unused (--warn-unused-vars)"));
-  this->WarnUnusedAction->setCheckable(true);
 
   QAction* debugAction = OptionsMenu->addAction(tr("&Debug Output"));
   debugAction->setCheckable(true);
@@ -290,9 +287,6 @@ void CMakeSetupDialog::initialize()
   QObject::connect(this->WarnUninitializedAction, SIGNAL(triggered(bool)),
                    this->CMakeThread->cmakeInstance(),
                    SLOT(setWarnUninitializedMode(bool)));
-  QObject::connect(this->WarnUnusedAction, SIGNAL(triggered(bool)),
-                   this->CMakeThread->cmakeInstance(),
-                   SLOT(setWarnUnusedMode(bool)));
 
   if (!this->SourceDirectory->text().isEmpty() ||
       !this->BinaryDirectory->lineEdit()->text().isEmpty()) {
diff --git a/Source/QtDialog/CMakeSetupDialog.h b/Source/QtDialog/CMakeSetupDialog.h
index d1e2035..eba0b1e 100644
--- a/Source/QtDialog/CMakeSetupDialog.h
+++ b/Source/QtDialog/CMakeSetupDialog.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef CMakeSetupDialog_h
-#define CMakeSetupDialog_h
+#pragma once
 
 #include <memory>
 
@@ -111,7 +110,6 @@ protected:
   QAction* ConfigureAction;
   QAction* GenerateAction;
   QAction* WarnUninitializedAction;
-  QAction* WarnUnusedAction;
   QAction* InstallForCommandLineAction;
   State CurrentState;
 
@@ -147,5 +145,3 @@ protected:
   virtual void run();
   std::unique_ptr<QCMake> CMakeInstance;
 };
-
-#endif // CMakeSetupDialog_h
diff --git a/Source/QtDialog/Compilers.h b/Source/QtDialog/Compilers.h
index 931c935..5da0781 100644
--- a/Source/QtDialog/Compilers.h
+++ b/Source/QtDialog/Compilers.h
@@ -1,7 +1,6 @@
 
 
-#ifndef COMPILERS_HPP
-#define COMPILERS_HPP
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -21,5 +20,3 @@ public:
     this->setupUi(this);
   }
 };
-
-#endif
diff --git a/Source/QtDialog/FirstConfigure.h b/Source/QtDialog/FirstConfigure.h
index c26f489..4c757da 100644
--- a/Source/QtDialog/FirstConfigure.h
+++ b/Source/QtDialog/FirstConfigure.h
@@ -1,6 +1,5 @@
 
-#ifndef FirstConfigure_h
-#define FirstConfigure_h
+#pragma once
 
 #include <QWizard>
 #include <QWizardPage>
@@ -201,5 +200,3 @@ protected:
   ToolchainCompilerSetup* mToolchainCompilerSetupPage;
   QString mDefaultGenerator;
 };
-
-#endif // FirstConfigure_h
diff --git a/Source/QtDialog/QCMake.cxx b/Source/QtDialog/QCMake.cxx
index 776af81..6090256 100644
--- a/Source/QtDialog/QCMake.cxx
+++ b/Source/QtDialog/QCMake.cxx
@@ -21,7 +21,6 @@ QCMake::QCMake(QObject* p)
   : QObject(p)
 {
   this->WarnUninitializedMode = false;
-  this->WarnUnusedMode = false;
   qRegisterMetaType<QCMakeProperty>();
   qRegisterMetaType<QCMakePropertyList>();
 
@@ -170,7 +169,6 @@ void QCMake::configure()
   this->CMakeInstance->SetGeneratorToolset(this->Toolset.toLocal8Bit().data());
   this->CMakeInstance->LoadCache();
   this->CMakeInstance->SetWarnUninitialized(this->WarnUninitializedMode);
-  this->CMakeInstance->SetWarnUnused(this->WarnUnusedMode);
   this->CMakeInstance->PreLoadCMakeFiles();
 
   InterruptFlag = 0;
@@ -340,10 +338,10 @@ void QCMake::interrupt()
 
 bool QCMake::interruptCallback()
 {
-#if QT_VERSION < QT_VERSION_CHECK(5, 0, 0)
-  return this->InterruptFlag;
-#else
+#if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
   return this->InterruptFlag.load();
+#else
+  return this->InterruptFlag.loadRelaxed();
 #endif
 }
 
@@ -478,11 +476,6 @@ void QCMake::setWarnUninitializedMode(bool value)
   this->WarnUninitializedMode = value;
 }
 
-void QCMake::setWarnUnusedMode(bool value)
-{
-  this->WarnUnusedMode = value;
-}
-
 void QCMake::checkOpenPossible()
 {
   std::string data = this->BinaryDirectory.toLocal8Bit().data();
diff --git a/Source/QtDialog/QCMake.h b/Source/QtDialog/QCMake.h
index 110a971..e87660b 100644
--- a/Source/QtDialog/QCMake.h
+++ b/Source/QtDialog/QCMake.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef QCMake_h
-#define QCMake_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -114,8 +113,6 @@ public slots:
   void setDeprecatedWarningsAsErrors(bool value);
   /// set whether to run cmake with warnings about uninitialized variables
   void setWarnUninitializedMode(bool value);
-  /// set whether to run cmake with warnings about unused variables
-  void setWarnUnusedMode(bool value);
   /// check if project IDE open is possible and emit openPossible signal
   void checkOpenPossible();
 
@@ -175,8 +172,6 @@ protected:
   void stderrCallback(std::string const& msg);
 
   bool WarnUninitializedMode;
-  bool WarnUnusedMode;
-  bool WarnUnusedAllMode;
   QString SourceDirectory;
   QString BinaryDirectory;
   QString Generator;
@@ -186,5 +181,3 @@ protected:
   QString CMakeExecutable;
   QAtomicInt InterruptFlag;
 };
-
-#endif // QCMake_h
diff --git a/Source/QtDialog/QCMakeCacheView.cxx b/Source/QtDialog/QCMakeCacheView.cxx
index 9b24fbd..3bf4409 100644
--- a/Source/QtDialog/QCMakeCacheView.cxx
+++ b/Source/QtDialog/QCMakeCacheView.cxx
@@ -155,11 +155,7 @@ QModelIndex QCMakeCacheView::moveCursor(CursorAction act,
 
 void QCMakeCacheView::setShowAdvanced(bool s)
 {
-#if QT_VERSION >= 040300
-  // new 4.3 API that needs to be called.  what about an older Qt?
   this->SearchFilter->invalidate();
-#endif
-
   this->AdvancedFilter->setShowAdvanced(s);
 }
 
@@ -209,9 +205,7 @@ void QCMakeCacheModel::clear()
 
 void QCMakeCacheModel::setProperties(const QCMakePropertyList& props)
 {
-#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
   this->beginResetModel();
-#endif
 
   QSet<QCMakeProperty> newProps;
   QSet<QCMakeProperty> newProps2;
@@ -335,11 +329,7 @@ void QCMakeCacheModel::setProperties(const QCMakePropertyList& props)
   }
 
   this->blockSignals(b);
-#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
   this->endResetModel();
-#else
-  this->reset();
-#endif
 }
 
 QCMakeCacheModel::ViewType QCMakeCacheModel::viewType() const
@@ -349,9 +339,7 @@ QCMakeCacheModel::ViewType QCMakeCacheModel::viewType() const
 
 void QCMakeCacheModel::setViewType(QCMakeCacheModel::ViewType t)
 {
-#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
   this->beginResetModel();
-#endif
 
   this->View = t;
 
@@ -368,11 +356,7 @@ void QCMakeCacheModel::setViewType(QCMakeCacheModel::ViewType t)
   this->setProperties(oldProps);
   this->setProperties(props);
   this->blockSignals(b);
-#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
   this->endResetModel();
-#else
-  this->reset();
-#endif
 }
 
 void QCMakeCacheModel::setPropertyData(const QModelIndex& idx1,
@@ -498,8 +482,7 @@ QCMakePropertyList QCMakeCacheModel::properties() const
       // go to the next in the tree
       while (!idxs.isEmpty() &&
              (
-#if QT_VERSION >= QT_VERSION_CHECK(5, 0, 0) &&                                \
-  QT_VERSION < QT_VERSION_CHECK(5, 1, 0)
+#if QT_VERSION < QT_VERSION_CHECK(5, 1, 0)
                (idxs.last().row() + 1) >= rowCount(idxs.last().parent()) ||
 #endif
                !idxs.last().sibling(idxs.last().row() + 1, 0).isValid())) {
@@ -659,20 +642,6 @@ bool QCMakeCacheModelDelegate::editorEvent(QEvent* e,
   return success;
 }
 
-// Issue 205903 fixed in Qt 4.5.0.
-// Can remove this function and FileDialogFlag when minimum Qt version is 4.5
-bool QCMakeCacheModelDelegate::eventFilter(QObject* object, QEvent* evt)
-{
-  // workaround for what looks like a bug in Qt on macOS
-  // where it doesn't create a QWidget wrapper for the native file dialog
-  // so the Qt library ends up assuming the focus was lost to something else
-
-  if (evt->type() == QEvent::FocusOut && this->FileDialogFlag) {
-    return false;
-  }
-  return QItemDelegate::eventFilter(object, evt);
-}
-
 void QCMakeCacheModelDelegate::setModelData(QWidget* editor,
                                             QAbstractItemModel* model,
                                             const QModelIndex& index) const
diff --git a/Source/QtDialog/QCMakeCacheView.h b/Source/QtDialog/QCMakeCacheView.h
index bea1965..836a939 100644
--- a/Source/QtDialog/QCMakeCacheView.h
+++ b/Source/QtDialog/QCMakeCacheView.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef QCMakeCacheView_h
-#define QCMakeCacheView_h
+#pragma once
 
 #include "QCMake.h"
 #include <QItemDelegate>
@@ -144,7 +143,6 @@ public:
   bool editorEvent(QEvent* event, QAbstractItemModel* model,
                    const QStyleOptionViewItem& option,
                    const QModelIndex& index);
-  bool eventFilter(QObject* object, QEvent* event);
   void setModelData(QWidget* editor, QAbstractItemModel* model,
                     const QModelIndex& index) const;
   QSize sizeHint(const QStyleOptionViewItem& option,
@@ -165,5 +163,3 @@ protected:
   // properties changed by user via this delegate
   QSet<QCMakeProperty> mChanges;
 };
-
-#endif
diff --git a/Source/QtDialog/QCMakeWidgets.cxx b/Source/QtDialog/QCMakeWidgets.cxx
index 332a770..d16ea58 100644
--- a/Source/QtDialog/QCMakeWidgets.cxx
+++ b/Source/QtDialog/QCMakeWidgets.cxx
@@ -4,9 +4,9 @@
 
 #include <utility>
 
-#include <QDirModel>
 #include <QFileDialog>
 #include <QFileInfo>
+#include <QFileSystemModel>
 #include <QResizeEvent>
 #include <QToolButton>
 
@@ -88,20 +88,20 @@ void QCMakePathEditor::chooseFile()
   }
 }
 
-// use same QDirModel for all completers
-static QDirModel* fileDirModel()
+// use same QFileSystemModel for all completers
+static QFileSystemModel* fileDirModel()
 {
-  static QDirModel* m = nullptr;
+  static QFileSystemModel* m = nullptr;
   if (!m) {
-    m = new QDirModel();
+    m = new QFileSystemModel();
   }
   return m;
 }
-static QDirModel* pathDirModel()
+static QFileSystemModel* pathDirModel()
 {
-  static QDirModel* m = nullptr;
+  static QFileSystemModel* m = nullptr;
   if (!m) {
-    m = new QDirModel();
+    m = new QFileSystemModel();
     m->setFilter(QDir::AllDirs | QDir::Drives | QDir::NoDotAndDotDot);
   }
   return m;
@@ -110,7 +110,7 @@ static QDirModel* pathDirModel()
 QCMakeFileCompleter::QCMakeFileCompleter(QObject* o, bool dirs)
   : QCompleter(o)
 {
-  QDirModel* m = dirs ? pathDirModel() : fileDirModel();
+  QFileSystemModel* m = dirs ? pathDirModel() : fileDirModel();
   this->setModel(m);
 }
 
diff --git a/Source/QtDialog/QCMakeWidgets.h b/Source/QtDialog/QCMakeWidgets.h
index 5d2368e..9a2a27e 100644
--- a/Source/QtDialog/QCMakeWidgets.h
+++ b/Source/QtDialog/QCMakeWidgets.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef QCMakeWidgets_h
-#define QCMakeWidgets_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -77,5 +76,3 @@ public:
     }
   }
 };
-
-#endif
diff --git a/Source/QtDialog/RegexExplorer.h b/Source/QtDialog/RegexExplorer.h
index 1a1d770..9a42320 100644
--- a/Source/QtDialog/RegexExplorer.h
+++ b/Source/QtDialog/RegexExplorer.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef RegexExplorer_h
-#define RegexExplorer_h
+#pragma once
 
 #include <string>
 
@@ -39,5 +38,3 @@ private:
   std::string m_regex;
   bool m_matched;
 };
-
-#endif
diff --git a/Source/QtDialog/WarningMessagesDialog.h b/Source/QtDialog/WarningMessagesDialog.h
index f209dbd..bb01704 100644
--- a/Source/QtDialog/WarningMessagesDialog.h
+++ b/Source/QtDialog/WarningMessagesDialog.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef WarningMessagesDialog_h
-#define WarningMessagesDialog_h
+#pragma once
 
 #include "QCMake.h"
 #include <QDialog>
@@ -63,5 +62,3 @@ private:
    */
   void setupSignals();
 };
-
-#endif /* MessageDialog_h */
diff --git a/Source/bindexplib.h b/Source/bindexplib.h
index 538177d..bd1398f 100644
--- a/Source/bindexplib.h
+++ b/Source/bindexplib.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef bindexplib_h
-#define bindexplib_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -25,4 +24,3 @@ private:
   std::set<std::string> DataSymbols;
   std::string NmPath;
 };
-#endif
diff --git a/Source/cmAddCompileDefinitionsCommand.h b/Source/cmAddCompileDefinitionsCommand.h
index 4bd621c..29282d6 100644
--- a/Source/cmAddCompileDefinitionsCommand.h
+++ b/Source/cmAddCompileDefinitionsCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddCompileDefinitionsCommand_h
-#define cmAddCompileDefinitionsCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddCompileDefinitionsCommand(std::vector<std::string> const& args,
                                     cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddCompileOptionsCommand.h b/Source/cmAddCompileOptionsCommand.h
index b172412..076a427 100644
--- a/Source/cmAddCompileOptionsCommand.h
+++ b/Source/cmAddCompileOptionsCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddCompileOptionsCommand_h
-#define cmAddCompileOptionsCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddCompileOptionsCommand(std::vector<std::string> const& args,
                                 cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddCustomCommandCommand.h b/Source/cmAddCustomCommandCommand.h
index 4f8c58f..383d116 100644
--- a/Source/cmAddCustomCommandCommand.h
+++ b/Source/cmAddCustomCommandCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddCustomCommandCommand_h
-#define cmAddCustomCommandCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
                                cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddCustomTargetCommand.h b/Source/cmAddCustomTargetCommand.h
index e23ef9f..3b784cb 100644
--- a/Source/cmAddCustomTargetCommand.h
+++ b/Source/cmAddCustomTargetCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddCustomTargetCommand_h
-#define cmAddCustomTargetCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddCustomTargetCommand(std::vector<std::string> const& args,
                               cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddDefinitionsCommand.h b/Source/cmAddDefinitionsCommand.h
index a67f095..45b4554 100644
--- a/Source/cmAddDefinitionsCommand.h
+++ b/Source/cmAddDefinitionsCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddDefinitionsCommand_h
-#define cmAddDefinitionsCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddDefinitionsCommand(std::vector<std::string> const& args,
                              cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddDependenciesCommand.h b/Source/cmAddDependenciesCommand.h
index 0c60e3a..a767550 100644
--- a/Source/cmAddDependenciesCommand.h
+++ b/Source/cmAddDependenciesCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDependenciessCommand_h
-#define cmDependenciessCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddDependenciesCommand(std::vector<std::string> const& args,
                               cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddExecutableCommand.h b/Source/cmAddExecutableCommand.h
index f7bc273..032c14d 100644
--- a/Source/cmAddExecutableCommand.h
+++ b/Source/cmAddExecutableCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExecutablesCommand_h
-#define cmExecutablesCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddExecutableCommand(std::vector<std::string> const& args,
                             cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddLibraryCommand.cxx b/Source/cmAddLibraryCommand.cxx
index 3e5d764..f262fac 100644
--- a/Source/cmAddLibraryCommand.cxx
+++ b/Source/cmAddLibraryCommand.cxx
@@ -2,8 +2,6 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmAddLibraryCommand.h"
 
-#include <cmext/algorithm>
-
 #include "cmExecutionStatus.h"
 #include "cmGeneratorExpression.h"
 #include "cmGlobalGenerator.h"
@@ -111,20 +109,10 @@ bool cmAddLibraryCommand(std::vector<std::string> const& args,
           "INTERFACE library specified with conflicting ALIAS type.");
         return false;
       }
-      if (excludeFromAll) {
-        status.SetError(
-          "INTERFACE library may not be used with EXCLUDE_FROM_ALL.");
-        return false;
-      }
       ++s;
       type = cmStateEnums::INTERFACE_LIBRARY;
       haveSpecifiedType = true;
     } else if (*s == "EXCLUDE_FROM_ALL") {
-      if (type == cmStateEnums::INTERFACE_LIBRARY) {
-        status.SetError(
-          "INTERFACE library may not be used with EXCLUDE_FROM_ALL.");
-        return false;
-      }
       ++s;
       excludeFromAll = true;
     } else if (*s == "IMPORTED") {
@@ -143,10 +131,6 @@ bool cmAddLibraryCommand(std::vector<std::string> const& args,
   }
 
   if (type == cmStateEnums::INTERFACE_LIBRARY) {
-    if (s != args.end()) {
-      status.SetError("INTERFACE library requires no source arguments.");
-      return false;
-    }
     if (importGlobal && !importTarget) {
       status.SetError(
         "INTERFACE library specified as GLOBAL, but not as IMPORTED.");
@@ -302,8 +286,6 @@ bool cmAddLibraryCommand(std::vector<std::string> const& args,
     }
   }
 
-  std::vector<std::string> srclists;
-
   if (type == cmStateEnums::INTERFACE_LIBRARY) {
     if (!cmGeneratorExpression::IsValidTargetName(libName) ||
         libName.find("::") != std::string::npos) {
@@ -311,14 +293,10 @@ bool cmAddLibraryCommand(std::vector<std::string> const& args,
         cmStrCat("Invalid name for INTERFACE library target: ", libName));
       return false;
     }
-
-    mf.AddLibrary(libName, type, srclists, excludeFromAll);
-    return true;
   }
 
-  cm::append(srclists, s, args.end());
-
-  mf.AddLibrary(libName, type, srclists, excludeFromAll);
+  std::vector<std::string> srcs(s, args.end());
+  mf.AddLibrary(libName, type, srcs, excludeFromAll);
 
   return true;
 }
diff --git a/Source/cmAddLibraryCommand.h b/Source/cmAddLibraryCommand.h
index 609449c..a4a0ea0 100644
--- a/Source/cmAddLibraryCommand.h
+++ b/Source/cmAddLibraryCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLibrarysCommand_h
-#define cmLibrarysCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddLibraryCommand(std::vector<std::string> const& args,
                          cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddLinkOptionsCommand.h b/Source/cmAddLinkOptionsCommand.h
index 466fc32..5c9d5e4 100644
--- a/Source/cmAddLinkOptionsCommand.h
+++ b/Source/cmAddLinkOptionsCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddLinkOptionsCommand_h
-#define cmAddLinkOptionsCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddLinkOptionsCommand(std::vector<std::string> const& args,
                              cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddSubDirectoryCommand.h b/Source/cmAddSubDirectoryCommand.h
index 87da840..ece3b27 100644
--- a/Source/cmAddSubDirectoryCommand.h
+++ b/Source/cmAddSubDirectoryCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddSubDirectoryCommand_h
-#define cmAddSubDirectoryCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddSubDirectoryCommand(std::vector<std::string> const& args,
                               cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAddTestCommand.h b/Source/cmAddTestCommand.h
index 5877547..8cba2b1 100644
--- a/Source/cmAddTestCommand.h
+++ b/Source/cmAddTestCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAddTestCommand_h
-#define cmAddTestCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAddTestCommand(std::vector<std::string> const& args,
                       cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmAlgorithms.h b/Source/cmAlgorithms.h
index c8e8dcb..87000da 100644
--- a/Source/cmAlgorithms.h
+++ b/Source/cmAlgorithms.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAlgorithms_h
-#define cmAlgorithms_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -143,5 +142,3 @@ typename Range::const_iterator cmFindNot(Range const& r, T const& t)
 {
   return std::find_if(r.begin(), r.end(), [&t](T const& i) { return i != t; });
 }
-
-#endif
diff --git a/Source/cmArchiveWrite.h b/Source/cmArchiveWrite.h
index b643bce..fff4556 100644
--- a/Source/cmArchiveWrite.h
+++ b/Source/cmArchiveWrite.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmArchiveWrite_h
-#define cmArchiveWrite_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -180,5 +179,3 @@ private:
   cmArchiveWriteOptional<int> Permissions;
   cmArchiveWriteOptional<int> PermissionsMask;
 };
-
-#endif
diff --git a/Source/cmArgumentParser.h b/Source/cmArgumentParser.h
index 5d2dfa2..71ed844 100644
--- a/Source/cmArgumentParser.h
+++ b/Source/cmArgumentParser.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmArgumentParser_h
-#define cmArgumentParser_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -146,5 +145,3 @@ protected:
 private:
   ArgumentParser::ActionMap Bindings;
 };
-
-#endif
diff --git a/Source/cmAuxSourceDirectoryCommand.cxx b/Source/cmAuxSourceDirectoryCommand.cxx
index d6f7500e..15edcc5 100644
--- a/Source/cmAuxSourceDirectoryCommand.cxx
+++ b/Source/cmAuxSourceDirectoryCommand.cxx
@@ -36,10 +36,7 @@ bool cmAuxSourceDirectoryCommand(std::vector<std::string> const& args,
   }
 
   // was the list already populated
-  const char* def = mf.GetDefinition(args[1]);
-  if (def) {
-    sourceListValue = def;
-  }
+  sourceListValue = mf.GetSafeDefinition(args[1]);
 
   std::vector<std::string> files;
 
@@ -55,7 +52,7 @@ bool cmAuxSourceDirectoryCommand(std::vector<std::string> const& args,
         auto ext = cm::string_view(file).substr(dotpos + 1);
         // Process only source files
         auto cm = mf.GetCMakeInstance();
-        if (dotpos > 0 && cm->IsSourceExtension(ext)) {
+        if (dotpos > 0 && cm->IsACLikeSourceExtension(ext)) {
           std::string fullname = cmStrCat(templateDirectory, '/', file);
           // add the file as a class file so
           // depends can be done
diff --git a/Source/cmAuxSourceDirectoryCommand.h b/Source/cmAuxSourceDirectoryCommand.h
index ae26092..29ee429 100644
--- a/Source/cmAuxSourceDirectoryCommand.h
+++ b/Source/cmAuxSourceDirectoryCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmAuxSourceDirectoryCommand_h
-#define cmAuxSourceDirectoryCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmAuxSourceDirectoryCommand(std::vector<std::string> const& args,
                                  cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmBase32.h b/Source/cmBase32.h
index d85198d..726f45d 100644
--- a/Source/cmBase32.h
+++ b/Source/cmBase32.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmBase32_h
-#define cmBase32_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -29,5 +28,3 @@ public:
   std::string encodeString(const unsigned char* input, size_t len,
                            bool padding = true);
 };
-
-#endif
diff --git a/Source/cmBinUtilsLinker.h b/Source/cmBinUtilsLinker.h
index 78d517b..5330070 100644
--- a/Source/cmBinUtilsLinker.h
+++ b/Source/cmBinUtilsLinker.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsLinker_h
-#define cmBinUtilsLinker_h
+#pragma once
 
 #include <string>
 
@@ -26,5 +25,3 @@ protected:
 
   void SetError(const std::string& e);
 };
-
-#endif // cmBinUtilsLinker_h
diff --git a/Source/cmBinUtilsLinuxELFGetRuntimeDependenciesTool.h b/Source/cmBinUtilsLinuxELFGetRuntimeDependenciesTool.h
index d514e7f..15216a4 100644
--- a/Source/cmBinUtilsLinuxELFGetRuntimeDependenciesTool.h
+++ b/Source/cmBinUtilsLinuxELFGetRuntimeDependenciesTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsLinuxELFGetRuntimeDependenciesTool_h
-#define cmBinUtilsLinuxELFGetRuntimeDependenciesTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -26,5 +25,3 @@ protected:
 
   void SetError(const std::string& e);
 };
-
-#endif // cmBinUtilsLinuxELFGetRuntimeDependenciesTool_h
diff --git a/Source/cmBinUtilsLinuxELFLinker.h b/Source/cmBinUtilsLinuxELFLinker.h
index b17df11..4e7e36d 100644
--- a/Source/cmBinUtilsLinuxELFLinker.h
+++ b/Source/cmBinUtilsLinuxELFLinker.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsLinuxELFLinker_h
-#define cmBinUtilsLinuxELFLinker_h
+#pragma once
 
 #include <memory>
 #include <string>
@@ -40,5 +39,3 @@ private:
 
   bool GetLDConfigPaths();
 };
-
-#endif // cmBinUtilsLinuxELFLinker_h
diff --git a/Source/cmBinUtilsLinuxELFObjdumpGetRuntimeDependenciesTool.h b/Source/cmBinUtilsLinuxELFObjdumpGetRuntimeDependenciesTool.h
index 969e4d4..def1dd0 100644
--- a/Source/cmBinUtilsLinuxELFObjdumpGetRuntimeDependenciesTool.h
+++ b/Source/cmBinUtilsLinuxELFObjdumpGetRuntimeDependenciesTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsLinuxELFGetRuntimeCollectDependenciesTool_h
-#define cmBinUtilsLinuxELFGetRuntimeCollectDependenciesTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -22,5 +21,3 @@ public:
                    std::vector<std::string>& rpaths,
                    std::vector<std::string>& runpaths) override;
 };
-
-#endif // cmBinUtilsLinuxELFObjdumpGetRuntimeDependenciesTool_h
diff --git a/Source/cmBinUtilsMacOSMachOGetRuntimeDependenciesTool.h b/Source/cmBinUtilsMacOSMachOGetRuntimeDependenciesTool.h
index dbb2882..60d34aa 100644
--- a/Source/cmBinUtilsMacOSMachOGetRuntimeDependenciesTool.h
+++ b/Source/cmBinUtilsMacOSMachOGetRuntimeDependenciesTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsMacOSMachOGetRuntimeDependenciesTool_h
-#define cmBinUtilsMacOSMachOGetRuntimeDependenciesTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -25,5 +24,3 @@ protected:
 
   void SetError(const std::string& error);
 };
-
-#endif // cmBinUtilsMacOSMachOGetRuntimeDependenciesTool_h
diff --git a/Source/cmBinUtilsMacOSMachOLinker.h b/Source/cmBinUtilsMacOSMachOLinker.h
index 4a24ea3..1c4a5fc 100644
--- a/Source/cmBinUtilsMacOSMachOLinker.h
+++ b/Source/cmBinUtilsMacOSMachOLinker.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsMacOSMachOLinker_h
-#define cmBinUtilsMacOSMachOLinker_h
+#pragma once
 
 #include <memory>
 #include <string>
@@ -55,5 +54,3 @@ private:
                               std::vector<std::string> const& rpaths,
                               std::string& path, bool& resolved);
 };
-
-#endif // cmBinUtilsMacOSMachOLinker_h
diff --git a/Source/cmBinUtilsMacOSMachOOToolGetRuntimeDependenciesTool.h b/Source/cmBinUtilsMacOSMachOOToolGetRuntimeDependenciesTool.h
index 8ac7e18..9d17450 100644
--- a/Source/cmBinUtilsMacOSMachOOToolGetRuntimeDependenciesTool.h
+++ b/Source/cmBinUtilsMacOSMachOOToolGetRuntimeDependenciesTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsMacOSMachOOToolGetRuntimeDependenciesTool_h
-#define cmBinUtilsMacOSMachOOToolGetRuntimeDependenciesTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -21,5 +20,3 @@ public:
   bool GetFileInfo(std::string const& file, std::vector<std::string>& libs,
                    std::vector<std::string>& rpaths) override;
 };
-
-#endif // cmBinUtilsMacOSMachOOToolGetRuntimeDependenciesTool_h
diff --git a/Source/cmBinUtilsWindowsPEDumpbinGetRuntimeDependenciesTool.h b/Source/cmBinUtilsWindowsPEDumpbinGetRuntimeDependenciesTool.h
index eae22ea..8609479 100644
--- a/Source/cmBinUtilsWindowsPEDumpbinGetRuntimeDependenciesTool.h
+++ b/Source/cmBinUtilsWindowsPEDumpbinGetRuntimeDependenciesTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsWindowsPEDumpbinGetRuntimeDependenciesTool_h
-#define cmBinUtilsWindowsPEDumpbinGetRuntimeDependenciesTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -21,5 +20,3 @@ public:
   bool GetFileInfo(const std::string& file,
                    std::vector<std::string>& needed) override;
 };
-
-#endif // cmBinUtilsWindowsPEDumpbinGetRuntimeDependenciesTool_h
diff --git a/Source/cmBinUtilsWindowsPEGetRuntimeDependenciesTool.h b/Source/cmBinUtilsWindowsPEGetRuntimeDependenciesTool.h
index e9e402b..da71aaa 100644
--- a/Source/cmBinUtilsWindowsPEGetRuntimeDependenciesTool.h
+++ b/Source/cmBinUtilsWindowsPEGetRuntimeDependenciesTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsWindowsPEGetRuntimeDependenciesTool_h
-#define cmBinUtilsWindowsPEGetRuntimeDependenciesTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -24,5 +23,3 @@ protected:
 
   void SetError(const std::string& error);
 };
-
-#endif // cmBinUtilsWindowsPEGetRuntimeDependenciesTool_h
diff --git a/Source/cmBinUtilsWindowsPELinker.h b/Source/cmBinUtilsWindowsPELinker.h
index a8bb596..6bb7875 100644
--- a/Source/cmBinUtilsWindowsPELinker.h
+++ b/Source/cmBinUtilsWindowsPELinker.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsWindowsPELinker_h
-#define cmBinUtilsWindowsPELinker_h
+#pragma once
 
 #include <memory>
 #include <string>
@@ -29,5 +28,3 @@ private:
   bool ResolveDependency(std::string const& name, std::string const& origin,
                          std::string& path, bool& resolved);
 };
-
-#endif // cmBinUtilsWindowsPELinker_h
diff --git a/Source/cmBinUtilsWindowsPEObjdumpGetRuntimeDependenciesTool.h b/Source/cmBinUtilsWindowsPEObjdumpGetRuntimeDependenciesTool.h
index a67cb0c..fe89a2d 100644
--- a/Source/cmBinUtilsWindowsPEObjdumpGetRuntimeDependenciesTool.h
+++ b/Source/cmBinUtilsWindowsPEObjdumpGetRuntimeDependenciesTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmBinUtilsWindowsPEObjdumpGetRuntimeDependenciesTool_h
-#define cmBinUtilsWindowsPEObjdumpGetRuntimeDependenciesTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -21,5 +20,3 @@ public:
   bool GetFileInfo(const std::string& file,
                    std::vector<std::string>& needed) override;
 };
-
-#endif // cmBinUtilsWindowsPEObjdumpGetRuntimeDependenciesTool_h
diff --git a/Source/cmBreakCommand.h b/Source/cmBreakCommand.h
index e6ce6fe..6241867 100644
--- a/Source/cmBreakCommand.h
+++ b/Source/cmBreakCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmBreakCommand_h
-#define cmBreakCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -17,5 +16,3 @@ class cmExecutionStatus;
  */
 bool cmBreakCommand(std::vector<std::string> const& args,
                     cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmBuildCommand.cxx b/Source/cmBuildCommand.cxx
index b82fb9a..2eaf315 100644
--- a/Source/cmBuildCommand.cxx
+++ b/Source/cmBuildCommand.cxx
@@ -6,6 +6,7 @@
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -94,7 +95,7 @@ bool TwoArgsSignature(std::vector<std::string> const& args,
   cmMakefile& mf = status.GetMakefile();
 
   std::string const& define = args[0];
-  const char* cacheValue = mf.GetDefinition(define);
+  cmProp cacheValue = mf.GetDefinition(define);
 
   std::string configType;
   if (!cmSystemTools::GetEnv("CMAKE_CONFIG_TYPE", configType) ||
diff --git a/Source/cmBuildCommand.h b/Source/cmBuildCommand.h
index 45aa71d..eafe185 100644
--- a/Source/cmBuildCommand.h
+++ b/Source/cmBuildCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmBuildCommand_h
-#define cmBuildCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmBuildCommand(std::vector<std::string> const& args,
                     cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmBuildNameCommand.cxx b/Source/cmBuildNameCommand.cxx
index ad4d665..f9b8f8f 100644
--- a/Source/cmBuildNameCommand.cxx
+++ b/Source/cmBuildNameCommand.cxx
@@ -8,6 +8,7 @@
 
 #include "cmExecutionStatus.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmStateTypes.h"
 #include "cmSystemTools.h"
 
@@ -19,12 +20,12 @@ bool cmBuildNameCommand(std::vector<std::string> const& args,
     return false;
   }
   cmMakefile& mf = status.GetMakefile();
-  const char* cacheValue = mf.GetDefinition(args[0]);
+  cmProp cacheValue = mf.GetDefinition(args[0]);
   if (cacheValue) {
     // do we need to correct the value?
     cmsys::RegularExpression reg("[()/]");
-    if (reg.find(cacheValue)) {
-      std::string cv = cacheValue;
+    std::string cv = *cacheValue;
+    if (reg.find(cv)) {
       std::replace(cv.begin(), cv.end(), '/', '_');
       std::replace(cv.begin(), cv.end(), '(', '_');
       std::replace(cv.begin(), cv.end(), ')', '_');
diff --git a/Source/cmBuildNameCommand.h b/Source/cmBuildNameCommand.h
index 37a7268..650dc74 100644
--- a/Source/cmBuildNameCommand.h
+++ b/Source/cmBuildNameCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmBuildNameCommand_h
-#define cmBuildNameCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmBuildNameCommand(std::vector<std::string> const& args,
                         cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCLocaleEnvironmentScope.h b/Source/cmCLocaleEnvironmentScope.h
index aa2827e..0919acc 100644
--- a/Source/cmCLocaleEnvironmentScope.h
+++ b/Source/cmCLocaleEnvironmentScope.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCLocaleEnvironmentScope_h
-#define cmCLocaleEnvironmentScope_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -25,5 +24,3 @@ private:
   using backup_map_t = std::map<std::string, std::string>;
   backup_map_t EnvironmentBackup;
 };
-
-#endif
diff --git a/Source/cmCMakeHostSystemInformationCommand.h b/Source/cmCMakeHostSystemInformationCommand.h
index 79e3f27..8a64f6a 100644
--- a/Source/cmCMakeHostSystemInformationCommand.h
+++ b/Source/cmCMakeHostSystemInformationCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCMakeHostSystemInformationCommand_h
-#define cmCMakeHostSystemInformationCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -18,5 +17,3 @@ class cmExecutionStatus;
  */
 bool cmCMakeHostSystemInformationCommand(std::vector<std::string> const& args,
                                          cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCMakeLanguageCommand.h b/Source/cmCMakeLanguageCommand.h
index 7306515..d45003a 100644
--- a/Source/cmCMakeLanguageCommand.h
+++ b/Source/cmCMakeLanguageCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCMakeLanguageCommand_h
-#define cmCMakeLanguageCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -11,10 +10,8 @@ class cmExecutionStatus;
 struct cmListFileArgument;
 
 /**
- * \brief Calls a scripted or build-in command
+ * \brief Calls a scripted or built-in command
  *
  */
 bool cmCMakeLanguageCommand(std::vector<cmListFileArgument> const& args,
                             cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCMakeMinimumRequired.h b/Source/cmCMakeMinimumRequired.h
index 53f78f6..712d6d6 100644
--- a/Source/cmCMakeMinimumRequired.h
+++ b/Source/cmCMakeMinimumRequired.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCMakeMinimumRequired_h
-#define cmCMakeMinimumRequired_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -17,5 +16,3 @@ class cmExecutionStatus;
  */
 bool cmCMakeMinimumRequired(std::vector<std::string> const& args,
                             cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCMakePath.cxx b/Source/cmCMakePath.cxx
new file mode 100644
index 0000000..b8215df
--- /dev/null
+++ b/Source/cmCMakePath.cxx
@@ -0,0 +1,146 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+
+#include "cmConfigure.h" // IWYU pragma: keep
+
+#include "cmCMakePath.h"
+
+#include <string>
+
+#if defined(_WIN32)
+#  include <cstdlib>
+#endif
+
+#include <cm/filesystem>
+#include <cm/string_view>
+
+#if defined(_WIN32)
+#  include "cmStringAlgorithms.h"
+#endif
+
+cmCMakePath& cmCMakePath::ReplaceWideExtension(cm::string_view extension)
+{
+  auto file = this->Path.filename().string();
+  if (!file.empty() && file != "." && file != "..") {
+    auto pos = file.find('.', file[0] == '.' ? 1 : 0);
+    if (pos != std::string::npos) {
+      file.erase(pos);
+    }
+  }
+  if (!extension.empty()) {
+    if (extension[0] != '.') {
+      file += '.';
+    }
+    file.append(std::string(extension));
+  }
+  this->Path.replace_filename(file);
+  return *this;
+}
+
+cmCMakePath cmCMakePath::GetWideExtension() const
+{
+  auto file = this->Path.filename().string();
+  if (file.empty() || file == "." || file == "..") {
+    return cmCMakePath{};
+  }
+
+  auto pos = file.find('.', file[0] == '.' ? 1 : 0);
+  if (pos != std::string::npos) {
+    return cm::string_view(file.data() + pos, file.length() - pos);
+  }
+
+  return cmCMakePath{};
+}
+
+cmCMakePath cmCMakePath::GetNarrowStem() const
+{
+  auto stem = this->Path.stem().string();
+  if (!stem.empty()) {
+    auto pos = stem.find('.', stem[0] == '.' ? 1 : 0);
+    if (pos != std::string::npos) {
+      return stem.substr(0, pos);
+    }
+  }
+  return stem;
+}
+
+cmCMakePath cmCMakePath::Absolute(const cm::filesystem::path& base) const
+{
+  if (this->Path.is_relative()) {
+    auto path = base;
+    path /= this->Path;
+    // filesystem::path::operator/= use preferred_separator ('\' on Windows)
+    // so converts back to '/'
+    return path.generic_string();
+  }
+  return *this;
+}
+
+bool cmCMakePath::IsPrefix(const cmCMakePath& path) const
+{
+  auto prefix_it = this->Path.begin();
+  auto prefix_end = this->Path.end();
+  auto path_it = path.Path.begin();
+  auto path_end = path.Path.end();
+
+  while (prefix_it != prefix_end && path_it != path_end &&
+         *prefix_it == *path_it) {
+    ++prefix_it;
+    ++path_it;
+  }
+  return prefix_it == prefix_end;
+}
+
+std::string cmCMakePath::FormatPath(std::string path, format fmt)
+{
+#if defined(_WIN32)
+  if (fmt == auto_format || fmt == native_format) {
+    auto prefix = path.substr(0, 4);
+    for (auto& c : prefix) {
+      if (c == '\\') {
+        c = '/';
+      }
+    }
+    // remove Windows long filename marker
+    if (prefix == "//?/"_s) {
+      path.erase(0, 4);
+    }
+    if (cmHasPrefix(path, "UNC/"_s) || cmHasPrefix(path, "UNC\\"_s)) {
+      path.erase(0, 2);
+      path[0] = '/';
+    }
+  }
+#else
+  static_cast<void>(fmt);
+#endif
+  return path;
+}
+
+void cmCMakePath::GetNativePath(std::string& path) const
+{
+  cm::filesystem::path tmp(this->Path);
+  tmp.make_preferred();
+
+  path = tmp.string();
+}
+void cmCMakePath::GetNativePath(std::wstring& path) const
+{
+  cm::filesystem::path tmp(this->Path);
+  tmp.make_preferred();
+
+  path = tmp.wstring();
+
+#if defined(_WIN32)
+  // Windows long filename
+  static std::wstring UNC(L"\\\\?\\UNC");
+  static std::wstring PREFIX(L"\\\\?\\");
+
+  if (this->IsAbsolute() && path.length() > _MAX_PATH - 12) {
+    if (this->HasRootName() && path[0] == L'\\') {
+      path = UNC + path.substr(1);
+    } else {
+      path = PREFIX + path;
+    }
+  }
+#endif
+}
diff --git a/Source/cmCMakePath.h b/Source/cmCMakePath.h
new file mode 100644
index 0000000..15aa30c
--- /dev/null
+++ b/Source/cmCMakePath.h
@@ -0,0 +1,571 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+
+#pragma once
+
+#include "cmConfigure.h" // IWYU pragma: keep
+
+#include <cstddef>
+#include <string>
+#include <utility>
+
+#include <cm/filesystem>
+#include <cm/string_view>
+#include <cm/type_traits>
+#include <cmext/string_view>
+
+namespace detail {
+#if defined(__SUNPRO_CC) && defined(__sparc)
+// Oracle DeveloperStudio C++ compiler on Solaris/Sparc fails to compile
+// the full 'is_pathable' and 'is_move_pathable' checks.  We use it only to
+// improve error messages via 'enable_if' when calling methods with incorrect
+// types. Just pretend all types are allowed so we can at least compile valid
+// code.
+template <typename T>
+struct is_pathable : std::true_type
+{
+};
+
+template <typename T>
+struct is_move_pathable : std::true_type
+{
+};
+
+#else
+template <typename T, typename = void>
+struct is_pathable : std::false_type
+{
+};
+
+template <>
+struct is_pathable<cm::filesystem::path> : std::true_type
+{
+};
+template <>
+struct is_pathable<std::string> : std::true_type
+{
+};
+template <>
+struct is_pathable<cm::string_view> : std::true_type
+{
+};
+template <>
+struct is_pathable<cm::static_string_view> : std::true_type
+{
+};
+template <typename T>
+struct is_pathable<
+  T,
+  cm::enable_if_t<std::is_same<char*, typename std::decay<T>::type>::value,
+                  void>>
+  : cm::bool_constant<std::is_same<char*, typename std::decay<T>::type>::value>
+{
+};
+
+template <typename T>
+struct is_move_pathable : std::false_type
+{
+};
+
+template <>
+struct is_move_pathable<cm::filesystem::path> : std::true_type
+{
+};
+template <>
+struct is_move_pathable<std::string> : std::true_type
+{
+};
+#endif
+}
+
+class cmCMakePath
+{
+private:
+  template <typename Source>
+  using enable_if_move_pathable =
+    cm::enable_if_t<detail::is_move_pathable<Source>::value, cmCMakePath&>;
+
+  template <typename Source>
+  using enable_if_pathable =
+    cm::enable_if_t<detail::is_pathable<Source>::value, cmCMakePath&>;
+
+public:
+  using value_type = cm::filesystem::path::value_type;
+  using string_type = cm::filesystem::path::string_type;
+
+  enum format : unsigned char
+  {
+    auto_format =
+      static_cast<unsigned char>(cm::filesystem::path::format::auto_format),
+    native_format =
+      static_cast<unsigned char>(cm::filesystem::path::format::native_format),
+    generic_format =
+      static_cast<unsigned char>(cm::filesystem::path::format::generic_format)
+  };
+
+  class iterator;
+  using const_iterator = iterator;
+
+  cmCMakePath() noexcept = default;
+
+  cmCMakePath(const cmCMakePath&) = default;
+
+  cmCMakePath(cmCMakePath&& path) noexcept
+    : Path(std::forward<cm::filesystem::path>(path.Path))
+  {
+  }
+
+  cmCMakePath(cm::filesystem::path path) noexcept
+    : Path(std::move(path))
+  {
+  }
+  cmCMakePath(cm::string_view source, format fmt = generic_format) noexcept
+    : Path(FormatPath(source, fmt))
+  {
+  }
+  template <typename Source, typename = enable_if_move_pathable<Source>>
+  cmCMakePath(Source source, format fmt = generic_format)
+    : Path(FormatPath(std::move(source), fmt))
+  {
+  }
+
+  template <typename Source, typename = enable_if_move_pathable<Source>>
+  cmCMakePath& Assign(Source&& source)
+  {
+    this->Path = std::forward<Source>(source);
+    return *this;
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& Assign(const Source& source)
+  {
+    this->Path = source;
+    return *this;
+  }
+
+  cmCMakePath& operator=(const cmCMakePath& path)
+  {
+    if (this != &path) {
+      this->Path = path.Path;
+    }
+    return *this;
+  }
+  cmCMakePath& operator=(cmCMakePath&& path) noexcept
+  {
+    if (this != &path) {
+      this->Path = std::move(path.Path);
+    }
+    return *this;
+  }
+  template <typename Source, typename = enable_if_move_pathable<Source>>
+  cmCMakePath& operator=(Source&& source)
+  {
+    this->Assign(std::forward<Source>(source));
+    return *this;
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& operator=(const Source& source)
+  {
+    this->Assign(source);
+    return *this;
+  }
+
+  // Concatenation
+  cmCMakePath& Append(const cmCMakePath& path)
+  {
+    return this->Append(path.Path);
+  }
+  cmCMakePath& Append(const cm::filesystem::path& path)
+  {
+    this->Path /= path;
+    // filesystem::path::append use preferred_separator ('\' on Windows)
+    // so convert back to '/'
+    this->Path = this->Path.generic_string();
+    return *this;
+  }
+
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& Append(const Source& source)
+  {
+    return this->Append(cm::filesystem::path(source));
+  }
+
+  cmCMakePath& operator/=(const cmCMakePath& path)
+  {
+    return this->Append(path);
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& operator/=(const Source& source)
+  {
+    return this->Append(source);
+  }
+
+  cmCMakePath& Concat(const cmCMakePath& path)
+  {
+    this->Path += path.Path;
+    return *this;
+  }
+  cmCMakePath& Concat(cm::static_string_view source)
+  {
+    this->Path.concat(std::string(source));
+    return *this;
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& Concat(const Source& source)
+  {
+    this->Path.concat(source);
+    return *this;
+  }
+
+  cmCMakePath& operator+=(const cmCMakePath& path)
+  {
+    return this->Concat(path);
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& operator+=(const Source& source)
+  {
+    return this->Concat(source);
+  }
+
+  // Manipulation
+  void Clear() noexcept { this->Path.clear(); }
+
+  cmCMakePath& RemoveFileName()
+  {
+    this->Path.remove_filename();
+    return *this;
+  }
+
+  cmCMakePath& ReplaceFileName(const cmCMakePath& filename)
+  {
+    if (this->Path.has_filename()) {
+      this->Path.replace_filename(filename.Path);
+    }
+    return *this;
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& ReplaceFileName(const Source& filename)
+  {
+    if (this->Path.has_filename()) {
+      this->Path.replace_filename(filename);
+    }
+    return *this;
+  }
+
+  cmCMakePath& ReplaceExtension(const cmCMakePath& extension = cmCMakePath())
+  {
+    this->Path.replace_extension(extension.Path);
+    return *this;
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& ReplaceExtension(const Source& extension)
+  {
+    this->Path.replace_extension(extension);
+    return *this;
+  }
+
+  cmCMakePath& ReplaceWideExtension(
+    const cmCMakePath& extension = cmCMakePath())
+  {
+    return this->ReplaceWideExtension(
+      static_cast<cm::string_view>(extension.Path.string()));
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath& ReplaceWideExtension(const Source& extension)
+  {
+    return this->ReplaceWideExtension(cm::string_view(extension));
+  }
+  cmCMakePath& ReplaceWideExtension(cm::string_view extension);
+
+  cmCMakePath& RemoveExtension()
+  {
+    if (this->Path.has_extension()) {
+      this->ReplaceExtension(cm::string_view(""));
+    }
+    return *this;
+  }
+
+  cmCMakePath& RemoveWideExtension()
+  {
+    if (this->Path.has_extension()) {
+      this->ReplaceWideExtension(cm::string_view(""));
+    }
+    return *this;
+  }
+
+  void swap(cmCMakePath& other) noexcept { this->Path.swap(other.Path); }
+
+  // Observers
+  std::string String() const { return this->Path.string(); }
+  std::wstring WString() const { return this->Path.wstring(); }
+
+  string_type Native() const
+  {
+    string_type path;
+    this->GetNativePath(path);
+
+    return path;
+  }
+  std::string NativeString() const
+  {
+    std::string path;
+    this->GetNativePath(path);
+
+    return path;
+  }
+  std::wstring NativeWString() const
+  {
+    std::wstring path;
+    this->GetNativePath(path);
+
+    return path;
+  }
+  std::string GenericString() const { return this->Path.generic_string(); }
+  std::wstring GenericWString() const { return this->Path.generic_wstring(); }
+
+  // Decomposition
+  cmCMakePath GetRootName() const { return this->Path.root_name(); }
+  cmCMakePath GetRootDirectory() const { return this->Path.root_directory(); }
+  cmCMakePath GetRootPath() const { return this->Path.root_path(); }
+  cmCMakePath GetFileName() const { return this->Path.filename(); }
+  cmCMakePath GetExtension() const { return this->Path.extension(); }
+  cmCMakePath GetWideExtension() const;
+  cmCMakePath GetStem() const { return this->Path.stem(); }
+  cmCMakePath GetNarrowStem() const;
+
+  cmCMakePath GetRelativePath() const { return this->Path.relative_path(); }
+  cmCMakePath GetParentPath() const { return this->Path.parent_path(); }
+
+  // Generation
+  cmCMakePath Normal() const
+  {
+    auto path = this->Path.lexically_normal();
+    // filesystem::path:lexically_normal use preferred_separator ('\') on
+    // Windows) so convert back to '/'
+    return path.generic_string();
+  }
+
+  cmCMakePath Relative(const cmCMakePath& base) const
+  {
+    return this->Relative(base.Path);
+  }
+  cmCMakePath Relative(const cm::filesystem::path& base) const
+  {
+    auto path = this->Path.lexically_relative(base);
+    // filesystem::path:lexically_relative use preferred_separator ('\') on
+    // Windows) so convert back to '/'
+    return path.generic_string();
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath Relative(const Source& base) const
+  {
+    return this->Relative(cm::filesystem::path(base));
+  }
+
+  cmCMakePath Proximate(const cmCMakePath& base) const
+  {
+    return this->Proximate(base.Path);
+  }
+  cmCMakePath Proximate(const cm::filesystem::path& base) const
+  {
+    auto path = this->Path.lexically_proximate(base);
+    // filesystem::path::lexically_proximate use preferred_separator ('\') on
+    // Windows) so convert back to '/'
+    return path.generic_string();
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath Proximate(const Source& base) const
+  {
+    return this->Proximate(cm::filesystem::path(base));
+  }
+
+  cmCMakePath Absolute(const cmCMakePath& base) const
+  {
+    return this->Absolute(base.Path);
+  }
+  template <typename Source, typename = enable_if_pathable<Source>>
+  cmCMakePath Absolute(const Source& base) const
+  {
+    return this->Absolute(cm::filesystem::path(base));
+  }
+  cmCMakePath Absolute(const cm::filesystem::path& base) const;
+
+  // Comparison
+  int Compare(const cmCMakePath& path) const noexcept
+  {
+    return this->Path.compare(path.Path);
+  }
+
+  // Query
+  bool IsEmpty() const noexcept { return this->Path.empty(); }
+
+  bool HasRootPath() const { return this->Path.has_root_path(); }
+  bool HasRootName() const { return this->Path.has_root_name(); }
+  bool HasRootDirectory() const { return this->Path.has_root_directory(); }
+  bool HasRelativePath() const { return this->Path.has_relative_path(); }
+  bool HasParentPath() const { return this->Path.has_parent_path(); }
+  bool HasFileName() const { return this->Path.has_filename(); }
+  bool HasStem() const { return this->Path.has_stem(); }
+  bool HasExtension() const { return this->Path.has_extension(); }
+
+  bool IsAbsolute() const { return this->Path.is_absolute(); }
+  bool IsRelative() const { return this->Path.is_relative(); }
+  bool IsPrefix(const cmCMakePath& path) const;
+
+  // Iterators
+  // =========
+  inline iterator begin() const;
+  inline iterator end() const;
+
+  // Non-members
+  // ===========
+  friend inline bool operator==(const cmCMakePath& lhs,
+                                const cmCMakePath& rhs) noexcept
+  {
+    return lhs.Compare(rhs) == 0;
+  }
+  friend inline bool operator!=(const cmCMakePath& lhs,
+                                const cmCMakePath& rhs) noexcept
+  {
+    return lhs.Compare(rhs) != 0;
+  }
+
+  friend inline cmCMakePath operator/(const cmCMakePath& lhs,
+                                      const cmCMakePath& rhs)
+  {
+    cmCMakePath result(lhs);
+    result /= rhs;
+
+    return result;
+  }
+
+private:
+  friend std::size_t hash_value(const cmCMakePath& path) noexcept;
+
+  static std::string FormatPath(std::string path, format fmt = generic_format);
+  static std::string FormatPath(cm::string_view path,
+                                format fmt = generic_format)
+  {
+    return FormatPath(std::string(path), fmt);
+  }
+
+  void GetNativePath(std::string& path) const;
+  void GetNativePath(std::wstring& path) const;
+
+  cm::filesystem::path Path;
+};
+
+class cmCMakePath::iterator
+{
+public:
+  using iterator_category = cm::filesystem::path::iterator::iterator_category;
+
+  using value_type = cmCMakePath;
+  using difference_type = cm::filesystem::path::iterator::difference_type;
+  using pointer = const cmCMakePath*;
+  using reference = const cmCMakePath&;
+
+  iterator() = default;
+
+  iterator(const iterator& other)
+    : Iterator(other.Iterator)
+    , Path(other.Path)
+    , PathElement(*this->Iterator)
+  {
+  }
+
+  ~iterator() = default;
+
+  iterator& operator=(const iterator& other)
+  {
+    if (this != &other) {
+      this->Iterator = other.Iterator;
+      this->Path = other.Path;
+      this->PathElement = *this->Iterator;
+    }
+
+    return *this;
+  }
+
+  reference operator*() const { return this->PathElement; }
+
+  pointer operator->() const { return &this->PathElement; }
+
+  iterator& operator++()
+  {
+    ++this->Iterator;
+    this->PathElement = *this->Iterator;
+
+    return *this;
+  }
+
+  iterator operator++(int)
+  {
+    iterator it(*this);
+    this->operator++();
+    return it;
+  }
+
+  iterator& operator--()
+  {
+    --this->Iterator;
+    this->PathElement = *this->Iterator;
+
+    return *this;
+  }
+
+  iterator operator--(int)
+  {
+    iterator it(*this);
+    this->operator--();
+    return it;
+  }
+
+private:
+  friend class cmCMakePath;
+  friend bool operator==(const iterator&, const iterator&);
+
+  iterator(const cmCMakePath* path, const cm::filesystem::path::iterator& it)
+    : Iterator(it)
+    , Path(path)
+    , PathElement(*this->Iterator)
+  {
+  }
+
+  cm::filesystem::path::iterator Iterator;
+  const cmCMakePath* Path = nullptr;
+  cmCMakePath PathElement;
+};
+
+inline cmCMakePath::iterator cmCMakePath::begin() const
+{
+  return iterator(this, this->Path.begin());
+}
+inline cmCMakePath::iterator cmCMakePath::end() const
+{
+  return iterator(this, this->Path.end());
+}
+
+// Non-member functions
+// ====================
+inline bool operator==(const cmCMakePath::iterator& lhs,
+                       const cmCMakePath::iterator& rhs)
+{
+  return lhs.Path == rhs.Path && lhs.Path != nullptr &&
+    lhs.Iterator == rhs.Iterator;
+}
+
+inline bool operator!=(const cmCMakePath::iterator& lhs,
+                       const cmCMakePath::iterator& rhs)
+{
+  return !(lhs == rhs);
+}
+
+inline void swap(cmCMakePath& lhs, cmCMakePath& rhs) noexcept
+{
+  lhs.swap(rhs);
+}
+
+inline std::size_t hash_value(const cmCMakePath& path) noexcept
+{
+  return cm::filesystem::hash_value(path.Path);
+}
diff --git a/Source/cmCMakePathCommand.cxx b/Source/cmCMakePathCommand.cxx
new file mode 100644
index 0000000..720f582
--- /dev/null
+++ b/Source/cmCMakePathCommand.cxx
@@ -0,0 +1,1019 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#include "cmCMakePathCommand.h"
+
+#include <algorithm>
+#include <functional>
+#include <iomanip>
+#include <map>
+#include <sstream>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include <cm/string_view>
+#include <cmext/string_view>
+
+#include "cmArgumentParser.h"
+#include "cmCMakePath.h"
+#include "cmExecutionStatus.h"
+#include "cmMakefile.h"
+#include "cmRange.h"
+#include "cmStringAlgorithms.h"
+#include "cmSubcommandTable.h"
+#include "cmSystemTools.h"
+
+namespace {
+// Helper classes for argument parsing
+template <typename Result>
+class CMakePathArgumentParser : public cmArgumentParser<Result>
+{
+public:
+  CMakePathArgumentParser()
+    : cmArgumentParser<Result>()
+  {
+  }
+
+  template <typename T>
+  CMakePathArgumentParser& Bind(cm::static_string_view name, T Result::*member)
+  {
+    cmArgumentParser<Result>::Bind(name, member);
+    return *this;
+  }
+
+  template <int Advance = 2>
+  Result Parse(std::vector<std::string> const& args,
+               std::vector<std::string>* keywordsMissingValue = nullptr,
+               std::vector<std::string>* parsedKeywords = nullptr) const
+  {
+    this->Inputs.clear();
+
+    return cmArgumentParser<Result>::Parse(cmMakeRange(args).advance(Advance),
+                                           &this->Inputs, keywordsMissingValue,
+                                           parsedKeywords);
+  }
+
+  const std::vector<std::string>& GetInputs() const { return Inputs; }
+
+protected:
+  mutable std::vector<std::string> Inputs;
+};
+
+// OUTPUT_VARIABLE is expected
+template <typename Result>
+class ArgumentParserWithOutputVariable : public CMakePathArgumentParser<Result>
+{
+public:
+  ArgumentParserWithOutputVariable()
+    : CMakePathArgumentParser<Result>()
+  {
+    this->Bind("OUTPUT_VARIABLE"_s, &Result::Output);
+  }
+
+  template <typename T>
+  ArgumentParserWithOutputVariable& Bind(cm::static_string_view name,
+                                         T Result::*member)
+  {
+    cmArgumentParser<Result>::Bind(name, member);
+    return *this;
+  }
+
+  template <int Advance = 2>
+  Result Parse(std::vector<std::string> const& args) const
+  {
+    this->KeywordsMissingValue.clear();
+    this->ParsedKeywords.clear();
+
+    return CMakePathArgumentParser<Result>::template Parse<Advance>(
+      args, &this->KeywordsMissingValue, &this->ParsedKeywords);
+  }
+
+  const std::vector<std::string>& GetKeywordsMissingValue() const
+  {
+    return this->KeywordsMissingValue;
+  }
+  const std::vector<std::string>& GetParsedKeywords() const
+  {
+    return this->ParsedKeywords;
+  }
+
+  bool checkOutputVariable(const Result& arguments,
+                           cmExecutionStatus& status) const
+  {
+    if (std::find(this->GetKeywordsMissingValue().begin(),
+                  this->GetKeywordsMissingValue().end(),
+                  "OUTPUT_VARIABLE"_s) !=
+        this->GetKeywordsMissingValue().end()) {
+      status.SetError("OUTPUT_VARIABLE requires an argument.");
+      return false;
+    }
+
+    if (std::find(this->GetParsedKeywords().begin(),
+                  this->GetParsedKeywords().end(),
+                  "OUTPUT_VARIABLE"_s) != this->GetParsedKeywords().end() &&
+        arguments.Output.empty()) {
+      status.SetError("Invalid name for output variable.");
+      return false;
+    }
+
+    return true;
+  }
+
+private:
+  mutable std::vector<std::string> KeywordsMissingValue;
+  mutable std::vector<std::string> ParsedKeywords;
+};
+
+struct OutputVariable
+{
+  std::string Output;
+};
+// Usable when OUTPUT_VARIABLE is the only option
+class OutputVariableParser
+  : public ArgumentParserWithOutputVariable<OutputVariable>
+{
+};
+
+struct NormalizeOption
+{
+  bool Normalize = false;
+};
+// Usable when NORMALIZE is the only option
+class NormalizeParser : public CMakePathArgumentParser<NormalizeOption>
+{
+public:
+  NormalizeParser() { this->Bind("NORMALIZE"_s, &NormalizeOption::Normalize); }
+};
+
+// retrieve value of input path from specified variable
+bool getInputPath(const std::string& arg, cmExecutionStatus& status,
+                  std::string& path)
+{
+  auto def = status.GetMakefile().GetDefinition(arg);
+  if (def == nullptr) {
+    status.SetError("undefined variable for input path.");
+    return false;
+  }
+
+  path = *def;
+  return true;
+}
+
+bool HandleGetCommand(std::vector<std::string> const& args,
+                      cmExecutionStatus& status)
+{
+  static std::map<cm::string_view,
+                  std::function<cmCMakePath(const cmCMakePath&, bool)>> const
+    actions{ { "ROOT_NAME"_s,
+               [](const cmCMakePath& path, bool) -> cmCMakePath {
+                 return path.GetRootName();
+               } },
+             { "ROOT_DIRECTORY"_s,
+               [](const cmCMakePath& path, bool) -> cmCMakePath {
+                 return path.GetRootDirectory();
+               } },
+             { "ROOT_PATH"_s,
+               [](const cmCMakePath& path, bool) -> cmCMakePath {
+                 return path.GetRootPath();
+               } },
+             { "FILENAME"_s,
+               [](const cmCMakePath& path, bool) -> cmCMakePath {
+                 return path.GetFileName();
+               } },
+             { "EXTENSION"_s,
+               [](const cmCMakePath& path, bool last_only) -> cmCMakePath {
+                 if (last_only) {
+                   return path.GetExtension();
+                 }
+                 return path.GetWideExtension();
+               } },
+             { "STEM"_s,
+               [](const cmCMakePath& path, bool last_only) -> cmCMakePath {
+                 if (last_only) {
+                   return path.GetStem();
+                 }
+                 return path.GetNarrowStem();
+               } },
+             { "RELATIVE_PATH"_s,
+               [](const cmCMakePath& path, bool) -> cmCMakePath {
+                 return path.GetRelativePath();
+               } },
+             { "PARENT_PATH"_s,
+               [](const cmCMakePath& path, bool) -> cmCMakePath {
+                 return path.GetParentPath();
+               } } };
+
+  if (args.size() < 4) {
+    status.SetError("GET must be called with at least three arguments.");
+    return false;
+  }
+
+  const auto& action = args[2];
+
+  if (actions.find(action) == actions.end()) {
+    status.SetError(
+      cmStrCat("GET called with an unknown action: ", action, "."));
+    return false;
+  }
+
+  struct Arguments
+  {
+    bool LastOnly = false;
+  };
+
+  CMakePathArgumentParser<Arguments> parser;
+  if ((action == "EXTENSION"_s || action == "STEM"_s)) {
+    parser.Bind("LAST_ONLY"_s, &Arguments::LastOnly);
+  }
+
+  Arguments const arguments = parser.Parse<3>(args);
+
+  if (parser.GetInputs().size() != 1) {
+    status.SetError("GET called with unexpected arguments.");
+    return false;
+  }
+  if (parser.GetInputs().front().empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  std::string path;
+  if (!getInputPath(args[1], status, path)) {
+    return false;
+  }
+
+  auto result = actions.at(action)(path, arguments.LastOnly);
+
+  status.GetMakefile().AddDefinition(parser.GetInputs().front(),
+                                     result.String());
+
+  return true;
+}
+
+bool HandleAppendCommand(std::vector<std::string> const& args,
+                         cmExecutionStatus& status)
+{
+  static OutputVariableParser const parser{};
+
+  const auto arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  cmCMakePath path(status.GetMakefile().GetSafeDefinition(args[1]));
+  for (const auto& input : parser.GetInputs()) {
+    path /= input;
+  }
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleConcatCommand(std::vector<std::string> const& args,
+                         cmExecutionStatus& status)
+{
+  static OutputVariableParser const parser{};
+
+  const auto arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  cmCMakePath path(inputPath);
+  for (const auto& input : parser.GetInputs()) {
+    path += input;
+  }
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleRemoveFilenameCommand(std::vector<std::string> const& args,
+                                 cmExecutionStatus& status)
+{
+  static OutputVariableParser const parser{};
+
+  const auto arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  if (!parser.GetInputs().empty()) {
+    status.SetError("REMOVE_FILENAME called with unexpected arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  cmCMakePath path(inputPath);
+  path.RemoveFileName();
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleReplaceFilenameCommand(std::vector<std::string> const& args,
+                                  cmExecutionStatus& status)
+{
+  static OutputVariableParser const parser{};
+
+  const auto arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  if (parser.GetInputs().size() > 1) {
+    status.SetError("REPLACE_FILENAME called with unexpected arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  cmCMakePath path(inputPath);
+  path.ReplaceFileName(
+    parser.GetInputs().empty() ? "" : parser.GetInputs().front());
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleRemoveExtensionCommand(std::vector<std::string> const& args,
+                                  cmExecutionStatus& status)
+{
+  struct Arguments
+  {
+    std::string Output;
+    bool LastOnly = false;
+  };
+
+  static auto const parser =
+    ArgumentParserWithOutputVariable<Arguments>{}.Bind("LAST_ONLY"_s,
+                                                       &Arguments::LastOnly);
+
+  Arguments const arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  if (!parser.GetInputs().empty()) {
+    status.SetError("REMOVE_EXTENSION called with unexpected arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  cmCMakePath path(inputPath);
+
+  if (arguments.LastOnly) {
+    path.RemoveExtension();
+  } else {
+    path.RemoveWideExtension();
+  }
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleReplaceExtensionCommand(std::vector<std::string> const& args,
+                                   cmExecutionStatus& status)
+{
+  struct Arguments
+  {
+    std::string Output;
+    bool LastOnly = false;
+  };
+
+  static auto const parser =
+    ArgumentParserWithOutputVariable<Arguments>{}.Bind("LAST_ONLY"_s,
+                                                       &Arguments::LastOnly);
+
+  Arguments const arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  if (parser.GetInputs().size() > 1) {
+    status.SetError("REPLACE_EXTENSION called with unexpected arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  cmCMakePath path(inputPath);
+  cmCMakePath extension(
+    parser.GetInputs().empty() ? "" : parser.GetInputs().front());
+
+  if (arguments.LastOnly) {
+    path.ReplaceExtension(extension);
+  } else {
+    path.ReplaceWideExtension(extension);
+  }
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleNormalPathCommand(std::vector<std::string> const& args,
+                             cmExecutionStatus& status)
+{
+  static OutputVariableParser const parser{};
+
+  const auto arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  if (!parser.GetInputs().empty()) {
+    status.SetError("NORMAL_PATH called with unexpected arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  auto path = cmCMakePath(inputPath).Normal();
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleTransformPathCommand(
+  std::vector<std::string> const& args, cmExecutionStatus& status,
+  const std::function<cmCMakePath(const cmCMakePath&,
+                                  const std::string& base)>& transform,
+  bool normalizeOption = false)
+{
+  struct Arguments
+  {
+    std::string Output;
+    std::string BaseDirectory;
+    bool Normalize = false;
+  };
+
+  auto parser = ArgumentParserWithOutputVariable<Arguments>{}.Bind(
+    "BASE_DIRECTORY"_s, &Arguments::BaseDirectory);
+  if (normalizeOption) {
+    parser.Bind("NORMALIZE"_s, &Arguments::Normalize);
+  }
+
+  Arguments arguments = parser.Parse(args);
+
+  if (!parser.checkOutputVariable(arguments, status)) {
+    return false;
+  }
+
+  if (!parser.GetInputs().empty()) {
+    status.SetError(cmStrCat(args[0], " called with unexpected arguments."));
+    return false;
+  }
+
+  if (std::find(parser.GetKeywordsMissingValue().begin(),
+                parser.GetKeywordsMissingValue().end(), "BASE_DIRECTORY"_s) !=
+      parser.GetKeywordsMissingValue().end()) {
+    status.SetError("BASE_DIRECTORY requires an argument.");
+    return false;
+  }
+
+  if (std::find(parser.GetParsedKeywords().begin(),
+                parser.GetParsedKeywords().end(),
+                "BASE_DIRECTORY"_s) == parser.GetParsedKeywords().end()) {
+    arguments.BaseDirectory = status.GetMakefile().GetCurrentSourceDirectory();
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  auto path = transform(cmCMakePath(inputPath), arguments.BaseDirectory);
+  if (arguments.Normalize) {
+    path = path.Normal();
+  }
+
+  status.GetMakefile().AddDefinition(
+    arguments.Output.empty() ? args[1] : arguments.Output, path.String());
+
+  return true;
+}
+
+bool HandleRelativePathCommand(std::vector<std::string> const& args,
+                               cmExecutionStatus& status)
+{
+  return HandleTransformPathCommand(
+    args, status,
+    [](const cmCMakePath& path, const std::string& base) -> cmCMakePath {
+      return path.Relative(base);
+    });
+}
+
+bool HandleProximatePathCommand(std::vector<std::string> const& args,
+                                cmExecutionStatus& status)
+{
+  return HandleTransformPathCommand(
+    args, status,
+    [](const cmCMakePath& path, const std::string& base) -> cmCMakePath {
+      return path.Proximate(base);
+    });
+}
+
+bool HandleAbsolutePathCommand(std::vector<std::string> const& args,
+                               cmExecutionStatus& status)
+{
+  return HandleTransformPathCommand(
+    args, status,
+    [](const cmCMakePath& path, const std::string& base) -> cmCMakePath {
+      return path.Absolute(base);
+    },
+    true);
+}
+
+bool HandleCMakePathCommand(std::vector<std::string> const& args,
+                            cmExecutionStatus& status)
+{
+  if (args.size() < 3 || args.size() > 4) {
+    status.SetError("CMAKE_PATH must be called with two or three arguments.");
+    return false;
+  }
+
+  static NormalizeParser const parser;
+
+  const auto arguments = parser.Parse(args);
+
+  if (parser.GetInputs().size() != 1) {
+    status.SetError("CMAKE_PATH called with unexpected arguments.");
+    return false;
+  }
+
+  if (args[1].empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  auto path =
+    cmCMakePath(parser.GetInputs().front(), cmCMakePath::native_format);
+
+  if (arguments.Normalize) {
+    path = path.Normal();
+  }
+
+  status.GetMakefile().AddDefinition(args[1], path.GenericString());
+
+  return true;
+}
+
+bool HandleNativePathCommand(std::vector<std::string> const& args,
+                             cmExecutionStatus& status)
+{
+  if (args.size() < 3 || args.size() > 4) {
+    status.SetError("NATIVE_PATH must be called with two or three arguments.");
+    return false;
+  }
+
+  static NormalizeParser const parser;
+
+  const auto arguments = parser.Parse(args);
+
+  if (parser.GetInputs().size() != 1) {
+    status.SetError("NATIVE_PATH called with unexpected arguments.");
+    return false;
+  }
+  if (parser.GetInputs().front().empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  cmCMakePath path(inputPath);
+  if (arguments.Normalize) {
+    path = path.Normal();
+  }
+
+  status.GetMakefile().AddDefinition(parser.GetInputs().front(),
+                                     path.NativeString());
+
+  return true;
+}
+
+bool HandleConvertCommand(std::vector<std::string> const& args,
+                          cmExecutionStatus& status)
+{
+#if defined(_WIN32) && !defined(__CYGWIN__)
+  const auto pathSep = ";"_s;
+#else
+  const auto pathSep = ":"_s;
+#endif
+  const auto cmakePath = "TO_CMAKE_PATH_LIST"_s;
+  const auto nativePath = "TO_NATIVE_PATH_LIST"_s;
+
+  if (args.size() < 4 || args.size() > 5) {
+    status.SetError("CONVERT must be called with three or four arguments.");
+    return false;
+  }
+
+  const auto& action = args[2];
+
+  if (action != cmakePath && action != nativePath) {
+    status.SetError(
+      cmStrCat("CONVERT called with an unknown action: ", action, "."));
+    return false;
+  }
+
+  if (args[3].empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  static NormalizeParser const parser;
+
+  const auto arguments = parser.Parse<4>(args);
+
+  if (!parser.GetInputs().empty()) {
+    status.SetError("CONVERT called with unexpected arguments.");
+    return false;
+  }
+
+  std::vector<std::string> paths;
+
+  if (action == cmakePath) {
+    paths = cmSystemTools::SplitString(args[1], pathSep.front());
+  } else {
+    cmExpandList(args[1], paths);
+  }
+
+  for (auto& path : paths) {
+    auto p = cmCMakePath(path,
+                         action == cmakePath ? cmCMakePath::native_format
+                                             : cmCMakePath::generic_format);
+    if (arguments.Normalize) {
+      p = p.Normal();
+    }
+    if (action == cmakePath) {
+      path = p.GenericString();
+    } else {
+      path = p.NativeString();
+    }
+  }
+
+  auto value = cmJoin(paths, action == cmakePath ? ";"_s : pathSep);
+  status.GetMakefile().AddDefinition(args[3], value);
+
+  return true;
+}
+
+bool HandleCompareCommand(std::vector<std::string> const& args,
+                          cmExecutionStatus& status)
+{
+  if (args.size() != 5) {
+    status.SetError("COMPARE must be called with four arguments.");
+    return false;
+  }
+
+  static std::map<cm::string_view,
+                  std::function<bool(const cmCMakePath&,
+                                     const cmCMakePath&)>> const operators{
+    { "EQUAL"_s,
+      [](const cmCMakePath& path1, const cmCMakePath& path2) -> bool {
+        return path1 == path2;
+      } },
+    { "NOT_EQUAL"_s,
+      [](const cmCMakePath& path1, const cmCMakePath& path2) -> bool {
+        return path1 != path2;
+      } }
+  };
+
+  const auto op = operators.find(args[2]);
+  if (op == operators.end()) {
+    status.SetError(cmStrCat(
+      "COMPARE called with an unknown comparison operator: ", args[2], "."));
+    return false;
+  }
+
+  if (args[4].empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  cmCMakePath path1(inputPath);
+  cmCMakePath path2(args[3]);
+  auto result = op->second(path1, path2);
+
+  status.GetMakefile().AddDefinitionBool(args[4], result);
+
+  return true;
+}
+
+bool HandleHasItemCommand(
+  std::vector<std::string> const& args, cmExecutionStatus& status,
+  const std::function<bool(const cmCMakePath&)>& has_item)
+{
+  if (args.size() != 3) {
+    status.SetError(
+      cmStrCat(args.front(), " must be called with two arguments."));
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  if (args[2].empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  cmCMakePath path(inputPath);
+  auto result = has_item(path);
+
+  status.GetMakefile().AddDefinitionBool(args[2], result);
+
+  return true;
+}
+
+bool HandleHasRootNameCommand(std::vector<std::string> const& args,
+                              cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasRootName(); });
+}
+
+bool HandleHasRootDirectoryCommand(std::vector<std::string> const& args,
+                                   cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasRootDirectory(); });
+}
+
+bool HandleHasRootPathCommand(std::vector<std::string> const& args,
+                              cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasRootPath(); });
+}
+
+bool HandleHasFilenameCommand(std::vector<std::string> const& args,
+                              cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasFileName(); });
+}
+
+bool HandleHasExtensionCommand(std::vector<std::string> const& args,
+                               cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasExtension(); });
+}
+
+bool HandleHasStemCommand(std::vector<std::string> const& args,
+                          cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasStem(); });
+}
+
+bool HandleHasRelativePathCommand(std::vector<std::string> const& args,
+                                  cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasRelativePath(); });
+}
+
+bool HandleHasParentPathCommand(std::vector<std::string> const& args,
+                                cmExecutionStatus& status)
+{
+  return HandleHasItemCommand(
+    args, status,
+    [](const cmCMakePath& path) -> bool { return path.HasParentPath(); });
+}
+
+bool HandleIsAbsoluteCommand(std::vector<std::string> const& args,
+                             cmExecutionStatus& status)
+{
+  if (args.size() != 3) {
+    status.SetError("IS_ABSOLUTE must be called with two arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  if (args[2].empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  bool isAbsolute = cmCMakePath(inputPath).IsAbsolute();
+
+  status.GetMakefile().AddDefinitionBool(args[2], isAbsolute);
+
+  return true;
+}
+
+bool HandleIsRelativeCommand(std::vector<std::string> const& args,
+                             cmExecutionStatus& status)
+{
+  if (args.size() != 3) {
+    status.SetError("IS_RELATIVE must be called with two arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  if (args[2].empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  bool isRelative = cmCMakePath(inputPath).IsRelative();
+
+  status.GetMakefile().AddDefinitionBool(args[2], isRelative);
+
+  return true;
+}
+
+bool HandleIsPrefixCommand(std::vector<std::string> const& args,
+                           cmExecutionStatus& status)
+{
+  if (args.size() < 4 || args.size() > 5) {
+    status.SetError("IS_PREFIX must be called with three or four arguments.");
+    return false;
+  }
+
+  static NormalizeParser const parser;
+
+  const auto arguments = parser.Parse(args);
+
+  if (parser.GetInputs().size() != 2) {
+    status.SetError("IS_PREFIX called with unexpected arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  const auto& input = parser.GetInputs().front();
+  const auto& output = parser.GetInputs().back();
+
+  if (output.empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  bool isPrefix;
+  if (arguments.Normalize) {
+    isPrefix =
+      cmCMakePath(inputPath).Normal().IsPrefix(cmCMakePath(input).Normal());
+  } else {
+    isPrefix = cmCMakePath(inputPath).IsPrefix(input);
+  }
+
+  status.GetMakefile().AddDefinitionBool(output, isPrefix);
+
+  return true;
+}
+
+bool HandleHashCommand(std::vector<std::string> const& args,
+                       cmExecutionStatus& status)
+{
+  if (args.size() < 3 || args.size() > 4) {
+    status.SetError("HASH must be called with two or three arguments.");
+    return false;
+  }
+
+  static NormalizeParser const parser;
+
+  const auto arguments = parser.Parse(args);
+
+  if (parser.GetInputs().size() != 1) {
+    status.SetError("HASH called with unexpected arguments.");
+    return false;
+  }
+
+  std::string inputPath;
+  if (!getInputPath(args[1], status, inputPath)) {
+    return false;
+  }
+
+  const auto& output = parser.GetInputs().front();
+
+  if (output.empty()) {
+    status.SetError("Invalid name for output variable.");
+    return false;
+  }
+
+  auto hash = hash_value(arguments.Normalize ? cmCMakePath(inputPath).Normal()
+                                             : cmCMakePath(inputPath));
+
+  std::ostringstream out;
+  out << std::setbase(16) << hash;
+
+  status.GetMakefile().AddDefinition(output, out.str());
+
+  return true;
+}
+} // anonymous namespace
+
+bool cmCMakePathCommand(std::vector<std::string> const& args,
+                        cmExecutionStatus& status)
+{
+  if (args.size() < 2) {
+    status.SetError("must be called with at least two arguments.");
+    return false;
+  }
+
+  static cmSubcommandTable const subcommand{
+    { "GET"_s, HandleGetCommand },
+    { "APPEND"_s, HandleAppendCommand },
+    { "CONCAT"_s, HandleConcatCommand },
+    { "REMOVE_FILENAME"_s, HandleRemoveFilenameCommand },
+    { "REPLACE_FILENAME"_s, HandleReplaceFilenameCommand },
+    { "REMOVE_EXTENSION"_s, HandleRemoveExtensionCommand },
+    { "REPLACE_EXTENSION"_s, HandleReplaceExtensionCommand },
+    { "NORMAL_PATH"_s, HandleNormalPathCommand },
+    { "RELATIVE_PATH"_s, HandleRelativePathCommand },
+    { "PROXIMATE_PATH"_s, HandleProximatePathCommand },
+    { "ABSOLUTE_PATH"_s, HandleAbsolutePathCommand },
+    { "CMAKE_PATH"_s, HandleCMakePathCommand },
+    { "NATIVE_PATH"_s, HandleNativePathCommand },
+    { "CONVERT"_s, HandleConvertCommand },
+    { "COMPARE"_s, HandleCompareCommand },
+    { "HAS_ROOT_NAME"_s, HandleHasRootNameCommand },
+    { "HAS_ROOT_DIRECTORY"_s, HandleHasRootDirectoryCommand },
+    { "HAS_ROOT_PATH"_s, HandleHasRootPathCommand },
+    { "HAS_FILENAME"_s, HandleHasFilenameCommand },
+    { "HAS_EXTENSION"_s, HandleHasExtensionCommand },
+    { "HAS_STEM"_s, HandleHasStemCommand },
+    { "HAS_RELATIVE_PATH"_s, HandleHasRelativePathCommand },
+    { "HAS_PARENT_PATH"_s, HandleHasParentPathCommand },
+    { "IS_ABSOLUTE"_s, HandleIsAbsoluteCommand },
+    { "IS_RELATIVE"_s, HandleIsRelativeCommand },
+    { "IS_PREFIX"_s, HandleIsPrefixCommand },
+    { "HASH"_s, HandleHashCommand }
+  };
+
+  return subcommand(args[0], args, status);
+}
diff --git a/Source/cmCMakePathCommand.h b/Source/cmCMakePathCommand.h
new file mode 100644
index 0000000..49e9380
--- /dev/null
+++ b/Source/cmCMakePathCommand.h
@@ -0,0 +1,14 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+
+#pragma once
+
+#include "cmConfigure.h" // IWYU pragma: keep
+
+#include <string>
+#include <vector>
+
+class cmExecutionStatus;
+
+bool cmCMakePathCommand(std::vector<std::string> const& args,
+                        cmExecutionStatus& status);
diff --git a/Source/cmCMakePolicyCommand.h b/Source/cmCMakePolicyCommand.h
index ba9397d..7346b66 100644
--- a/Source/cmCMakePolicyCommand.h
+++ b/Source/cmCMakePolicyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCMakePolicyCommand_h
-#define cmCMakePolicyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -18,5 +17,3 @@ class cmExecutionStatus;
  */
 bool cmCMakePolicyCommand(std::vector<std::string> const& args,
                           cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCPackPropertiesGenerator.h b/Source/cmCPackPropertiesGenerator.h
index 8339238..63c469a 100644
--- a/Source/cmCPackPropertiesGenerator.h
+++ b/Source/cmCPackPropertiesGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCPackPropertiesGenerator_h
-#define cmCPackPropertiesGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -36,5 +35,3 @@ protected:
   cmLocalGenerator* LG;
   cmInstalledFile const& InstalledFile;
 };
-
-#endif
diff --git a/Source/cmCPluginAPI.cxx b/Source/cmCPluginAPI.cxx
index 697d435..ee2960b 100644
--- a/Source/cmCPluginAPI.cxx
+++ b/Source/cmCPluginAPI.cxx
@@ -140,7 +140,7 @@ const char* CCONV cmGetCurrentOutputDirectory(void* arg)
 const char* CCONV cmGetDefinition(void* arg, const char* def)
 {
   cmMakefile* mf = static_cast<cmMakefile*>(arg);
-  return mf->GetDefinition(def);
+  return cmToCStr(mf->GetDefinition(def));
 }
 
 int CCONV cmIsOn(void* arg, const char* name)
@@ -581,13 +581,13 @@ const char* CCONV cmSourceFileGetProperty(void* arg, const char* prop)
   cmCPluginAPISourceFile* sf = static_cast<cmCPluginAPISourceFile*>(arg);
   if (cmSourceFile* rsf = sf->RealSourceFile) {
     cmProp p = rsf->GetProperty(prop);
-    return p ? p->c_str() : nullptr;
+    return cmToCStr(p);
   }
   if (!strcmp(prop, "LOCATION")) {
     return sf->FullPath.c_str();
   }
   cmProp retVal = sf->Properties.GetPropertyValue(prop);
-  return retVal ? retVal->c_str() : nullptr;
+  return cmToCStr(retVal);
 }
 
 int CCONV cmSourceFileGetPropertyAsBool(void* arg, const char* prop)
diff --git a/Source/cmCTest.cxx b/Source/cmCTest.cxx
index bca7540..8cf5ae9 100644
--- a/Source/cmCTest.cxx
+++ b/Source/cmCTest.cxx
@@ -394,7 +394,7 @@ bool cmCTest::ShouldCompressTestOutput()
   return this->Impl->CompressTestOutput;
 }
 
-cmCTest::Part cmCTest::GetPartFromName(const char* name)
+cmCTest::Part cmCTest::GetPartFromName(const std::string& name)
 {
   // Look up by lower-case to make names case-insensitive.
   std::string lower_name = cmSystemTools::LowerCase(name);
@@ -458,8 +458,7 @@ int cmCTest::Initialize(const char* binary_dir, cmCTestStartCommand* command)
   cm.GetCurrentSnapshot().SetDefaultDefinitions();
   cmGlobalGenerator gg(&cm);
   cmMakefile mf(&gg, cm.GetCurrentSnapshot());
-  if (!this->ReadCustomConfigurationFileTree(this->Impl->BinaryDir.c_str(),
-                                             &mf)) {
+  if (!this->ReadCustomConfigurationFileTree(this->Impl->BinaryDir, &mf)) {
     cmCTestOptionalLog(
       this, DEBUG, "Cannot find custom configuration file tree" << std::endl,
       quiet);
@@ -523,7 +522,7 @@ int cmCTest::Initialize(const char* binary_dir, cmCTestStartCommand* command)
         std::string model;
         if (cmSystemTools::GetLineFromStream(tfin, model) &&
             !this->Impl->Parts[PartStart] && !command) {
-          this->Impl->TestModel = GetTestModelFromString(model.c_str());
+          this->Impl->TestModel = GetTestModelFromString(model);
         }
         tfin.close();
       }
@@ -579,7 +578,7 @@ int cmCTest::Initialize(const char* binary_dir, cmCTestStartCommand* command)
         cmSystemTools::GetLineFromStream(tfin, tag);
         cmSystemTools::GetLineFromStream(tfin, group);
         if (cmSystemTools::GetLineFromStream(tfin, modelStr)) {
-          model = GetTestModelFromString(modelStr.c_str());
+          model = GetTestModelFromString(modelStr);
         }
         tfin.close();
       }
@@ -705,8 +704,7 @@ bool cmCTest::UpdateCTestConfiguration()
   if (!cmSystemTools::FileExists(fileName)) {
     // No need to exit if we are not producing XML
     if (this->Impl->ProduceXML) {
-      cmCTestLog(this, ERROR_MESSAGE,
-                 "Cannot find file: " << fileName << std::endl);
+      cmCTestLog(this, WARNING, "Cannot find file: " << fileName << std::endl);
       return false;
     }
   } else {
@@ -793,7 +791,7 @@ int cmCTest::GetTestModel() const
   return this->Impl->TestModel;
 }
 
-bool cmCTest::SetTest(const char* ttype, bool report)
+bool cmCTest::SetTest(const std::string& ttype, bool report)
 {
   if (cmSystemTools::LowerCase(ttype) == "all") {
     for (Part p = PartStart; p != PartCount; p = Part(p + 1)) {
@@ -841,6 +839,7 @@ bool cmCTest::OpenOutputFile(const std::string& path, const std::string& name,
     }
   }
   std::string filename = testingDir + "/" + name;
+  stream.SetTempExt("tmp");
   stream.Open(filename);
   if (!stream) {
     cmCTestLog(this, ERROR_MESSAGE,
@@ -855,7 +854,7 @@ bool cmCTest::OpenOutputFile(const std::string& path, const std::string& name,
   return true;
 }
 
-bool cmCTest::AddIfExists(Part part, const char* file)
+bool cmCTest::AddIfExists(Part part, const std::string& file)
 {
   if (this->CTestFileExists(file)) {
     this->AddSubmitFile(part, file);
@@ -1007,7 +1006,7 @@ int cmCTest::ProcessSteps()
   if (this->Impl->Parts[PartNotes]) {
     this->UpdateCTestConfiguration();
     if (!this->Impl->NotesFiles.empty()) {
-      this->GenerateNotesFile(this->Impl->NotesFiles.c_str());
+      this->GenerateNotesFile(this->Impl->NotesFiles);
     }
   }
   if (this->Impl->Parts[PartSubmit]) {
@@ -1036,9 +1035,9 @@ std::string cmCTest::GetTestModelString()
   return "Experimental";
 }
 
-int cmCTest::GetTestModelFromString(const char* str)
+int cmCTest::GetTestModelFromString(const std::string& str)
 {
-  if (!str) {
+  if (str.empty()) {
     return cmCTest::EXPERIMENTAL;
   }
   std::string rstr = cmSystemTools::LowerCase(str);
@@ -1564,9 +1563,9 @@ int cmCTest::GenerateNotesFile(std::vector<std::string> const& files)
   return 0;
 }
 
-int cmCTest::GenerateNotesFile(const char* cfiles)
+int cmCTest::GenerateNotesFile(const std::string& cfiles)
 {
-  if (!cfiles) {
+  if (cfiles.empty()) {
     return 1;
   }
 
@@ -1649,14 +1648,14 @@ bool cmCTest::SubmitExtraFiles(std::vector<std::string> const& files)
                                             << std::endl;);
       return false;
     }
-    this->AddSubmitFile(PartExtraFiles, file.c_str());
+    this->AddSubmitFile(PartExtraFiles, file);
   }
   return true;
 }
 
-bool cmCTest::SubmitExtraFiles(const char* cfiles)
+bool cmCTest::SubmitExtraFiles(const std::string& cfiles)
 {
-  if (!cfiles) {
+  if (cfiles.empty()) {
     return true;
   }
 
@@ -1940,7 +1939,7 @@ bool cmCTest::HandleCommandLineArguments(size_t& i,
   else if (this->CheckArgument(arg, "-C"_s, "--build-config") &&
            i < args.size() - 1) {
     i++;
-    this->SetConfigType(args[i].c_str());
+    this->SetConfigType(args[i]);
   }
 
   else if (this->CheckArgument(arg, "--debug"_s)) {
@@ -2015,7 +2014,7 @@ bool cmCTest::HandleCommandLineArguments(size_t& i,
   else if (this->CheckArgument(arg, "-O"_s, "--output-log") &&
            i < args.size() - 1) {
     i++;
-    this->SetOutputLogFileName(args[i].c_str());
+    this->SetOutputLogFileName(args[i]);
   }
 
   else if (this->CheckArgument(arg, "--tomorrow-tag"_s)) {
@@ -2047,7 +2046,7 @@ bool cmCTest::HandleCommandLineArguments(size_t& i,
     this->Impl->ProduceXML = true;
     this->SetTest("Notes");
     i++;
-    this->SetNotesFiles(args[i].c_str());
+    this->SetNotesFiles(args[i]);
     return true;
   }
 
@@ -2304,7 +2303,7 @@ int cmCTest::Run(std::vector<std::string>& args, std::string* output)
       this->Impl->ProduceXML = true;
       this->SetTest("Submit");
       i++;
-      if (!this->SubmitExtraFiles(args[i].c_str())) {
+      if (!this->SubmitExtraFiles(args[i])) {
         return 0;
       }
     }
@@ -2375,7 +2374,7 @@ bool cmCTest::HandleTestActionArgument(const char* ctestExec, size_t& i,
       (i < args.size() - 1)) {
     this->Impl->ProduceXML = true;
     i++;
-    if (!this->SetTest(args[i].c_str(), false)) {
+    if (!this->SetTest(args[i], false)) {
       success = false;
       cmCTestLog(this, ERROR_MESSAGE,
                  "CTest -T called with incorrect option: " << args[i]
@@ -2490,11 +2489,8 @@ int cmCTest::RunCMakeAndTest(std::string* output)
   return retv;
 }
 
-void cmCTest::SetNotesFiles(const char* notes)
+void cmCTest::SetNotesFiles(const std::string& notes)
 {
-  if (!notes) {
-    return;
-  }
   this->Impl->NotesFiles = notes;
 }
 
@@ -2560,7 +2556,8 @@ void cmCTest::SetScheduleType(std::string const& type)
   this->Impl->ScheduleType = type;
 }
 
-int cmCTest::ReadCustomConfigurationFileTree(const char* dir, cmMakefile* mf)
+int cmCTest::ReadCustomConfigurationFileTree(const std::string& dir,
+                                             cmMakefile* mf)
 {
   bool found = false;
   cmCTestLog(this, DEBUG,
@@ -2623,14 +2620,14 @@ int cmCTest::ReadCustomConfigurationFileTree(const char* dir, cmMakefile* mf)
 void cmCTest::PopulateCustomVector(cmMakefile* mf, const std::string& def,
                                    std::vector<std::string>& vec)
 {
-  const char* dval = mf->GetDefinition(def);
+  cmProp dval = mf->GetDefinition(def);
   if (!dval) {
     return;
   }
   cmCTestLog(this, DEBUG, "PopulateCustomVector: " << def << std::endl);
 
   vec.clear();
-  cmExpandList(dval, vec);
+  cmExpandList(*dval, vec);
 
   for (std::string const& it : vec) {
     cmCTestLog(this, DEBUG, "  -- " << it << std::endl);
@@ -2640,14 +2637,14 @@ void cmCTest::PopulateCustomVector(cmMakefile* mf, const std::string& def,
 void cmCTest::PopulateCustomInteger(cmMakefile* mf, const std::string& def,
                                     int& val)
 {
-  const char* dval = mf->GetDefinition(def);
+  cmProp dval = mf->GetDefinition(def);
   if (!dval) {
     return;
   }
-  val = atoi(dval);
+  val = atoi(dval->c_str());
 }
 
-std::string cmCTest::GetShortPathToFile(const char* cfname)
+std::string cmCTest::GetShortPathToFile(const std::string& cfname)
 {
   const std::string& sourceDir = cmSystemTools::CollapseFullPath(
     this->GetCTestConfiguration("SourceDirectory"));
@@ -2711,18 +2708,17 @@ void cmCTest::EmptyCTestConfiguration()
   this->Impl->CTestConfiguration.clear();
 }
 
-void cmCTest::SetCTestConfiguration(const char* name, const char* value,
+void cmCTest::SetCTestConfiguration(const char* name, const std::string& value,
                                     bool suppress)
 {
   cmCTestOptionalLog(this, HANDLER_VERBOSE_OUTPUT,
-                     "SetCTestConfiguration:"
-                       << name << ":" << (value ? value : "(null)") << "\n",
+                     "SetCTestConfiguration:" << name << ":" << value << "\n",
                      suppress);
 
   if (!name) {
     return;
   }
-  if (!value) {
+  if (value.empty()) {
     this->Impl->CTestConfiguration.erase(name);
     return;
   }
@@ -2927,7 +2923,7 @@ std::string cmCTest::GetBuildID() const
   return this->Impl->BuildID;
 }
 
-void cmCTest::AddSubmitFile(Part part, const char* name)
+void cmCTest::AddSubmitFile(Part part, const std::string& name)
 {
   this->Impl->Parts[part].SubmitFiles.emplace_back(name);
 }
@@ -2963,9 +2959,9 @@ void cmCTest::AddCTestConfigurationOverwrite(const std::string& overStr)
   this->Impl->CTestConfigurationOverwrites[key] = value;
 }
 
-void cmCTest::SetConfigType(const char* ct)
+void cmCTest::SetConfigType(const std::string& ct)
 {
-  this->Impl->ConfigType = ct ? ct : "";
+  this->Impl->ConfigType = ct;
   cmSystemTools::ReplaceString(this->Impl->ConfigType, ".\\", "");
   std::string confTypeEnv = "CMAKE_CONFIG_TYPE=" + this->Impl->ConfigType;
   cmSystemTools::PutEnv(confTypeEnv);
@@ -2975,8 +2971,7 @@ bool cmCTest::SetCTestConfigurationFromCMakeVariable(
   cmMakefile* mf, const char* dconfig, const std::string& cmake_var,
   bool suppress)
 {
-  const char* ctvar;
-  ctvar = mf->GetDefinition(cmake_var);
+  cmProp ctvar = mf->GetDefinition(cmake_var);
   if (!ctvar) {
     return false;
   }
@@ -2984,7 +2979,7 @@ bool cmCTest::SetCTestConfigurationFromCMakeVariable(
                      "SetCTestConfigurationFromCMakeVariable:"
                        << dconfig << ":" << cmake_var << std::endl,
                      suppress);
-  this->SetCTestConfiguration(dconfig, ctvar, suppress);
+  this->SetCTestConfiguration(dconfig, *ctvar, suppress);
   return true;
 }
 
@@ -3085,9 +3080,9 @@ bool cmCTest::RunCommand(std::vector<std::string> const& args,
   return result;
 }
 
-void cmCTest::SetOutputLogFileName(const char* name)
+void cmCTest::SetOutputLogFileName(const std::string& name)
 {
-  if (name) {
+  if (!name.empty()) {
     this->Impl->OutputLogFile = cm::make_unique<cmGeneratedFileStream>(name);
   } else {
     this->Impl->OutputLogFile.reset();
diff --git a/Source/cmCTest.h b/Source/cmCTest.h
index a39b8fe..e12f8b0 100644
--- a/Source/cmCTest.h
+++ b/Source/cmCTest.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCTest_h
-#define cmCTest_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -64,7 +63,7 @@ public:
 
   /** Get a testing part id from its string name.  Returns PartCount
       if the string does not name a valid part.  */
-  Part GetPartFromName(const char* name);
+  Part GetPartFromName(const std::string& name);
 
   /** Process Command line arguments */
   int Run(std::vector<std::string>&, std::string* output = nullptr);
@@ -127,12 +126,12 @@ public:
    * Check if CTest file exists
    */
   bool CTestFileExists(const std::string& filename);
-  bool AddIfExists(Part part, const char* file);
+  bool AddIfExists(Part part, const std::string& file);
 
   /**
    * Set the cmake test
    */
-  bool SetTest(const char*, bool report = true);
+  bool SetTest(const std::string&, bool report = true);
 
   /**
    * Set the cmake test mode (experimental, nightly, continuous).
@@ -141,11 +140,11 @@ public:
   int GetTestModel() const;
 
   std::string GetTestModelString();
-  static int GetTestModelFromString(const char* str);
+  static int GetTestModelFromString(const std::string& str);
   static std::string CleanString(const std::string& str,
                                  std::string::size_type spos = 0);
   std::string GetCTestConfiguration(const std::string& name);
-  void SetCTestConfiguration(const char* name, const char* value,
+  void SetCTestConfiguration(const char* name, const std::string& value,
                              bool suppress = false);
   void EmptyCTestConfiguration();
 
@@ -161,7 +160,7 @@ public:
   cmCTest& operator=(const cmCTest&) = delete;
 
   /** Set the notes files to be created. */
-  void SetNotesFiles(const char* notes);
+  void SetNotesFiles(const std::string& notes);
 
   void PopulateCustomVector(cmMakefile* mf, const std::string& definition,
                             std::vector<std::string>& vec);
@@ -272,7 +271,7 @@ public:
    * This means if the file is in binary or
    * source directory, it will become /.../relative/path/to/file
    */
-  std::string GetShortPathToFile(const char* fname);
+  std::string GetShortPathToFile(const std::string& fname);
 
   enum
   {
@@ -354,14 +353,14 @@ public:
   int GenerateDoneFile();
 
   /** Submit extra files to the server */
-  bool SubmitExtraFiles(const char* files);
+  bool SubmitExtraFiles(const std::string& files);
   bool SubmitExtraFiles(std::vector<std::string> const& files);
 
   /** Set the output log file name */
-  void SetOutputLogFileName(const char* name);
+  void SetOutputLogFileName(const std::string& name);
 
   /** Set the visual studio or Xcode config type */
-  void SetConfigType(const char* ct);
+  void SetConfigType(const std::string& ct);
 
   /** Various log types */
   enum
@@ -399,14 +398,14 @@ public:
   std::string GetBuildID() const;
 
   /** Add file to be submitted */
-  void AddSubmitFile(Part part, const char* name);
+  void AddSubmitFile(Part part, const std::string& name);
   std::vector<std::string> const& GetSubmitFiles(Part part) const;
   void ClearSubmitFiles(Part part);
 
   /**
    * Read the custom configuration files and apply them to the current ctest
    */
-  int ReadCustomConfigurationFileTree(const char* dir, cmMakefile* mf);
+  int ReadCustomConfigurationFileTree(const std::string& dir, cmMakefile* mf);
 
   std::vector<std::string>& GetInitialCommandLineArguments();
 
@@ -462,7 +461,7 @@ public:
   void SetRunCurrentScript(bool value);
 
 private:
-  int GenerateNotesFile(const char* files);
+  int GenerateNotesFile(const std::string& files);
 
   void BlockTestErrorDiagnostics();
 
@@ -571,5 +570,3 @@ inline std::ostream& operator<<(std::ostream& os, const cmCTestLogWrite& c)
     (ctSelf)->Log(cmCTest::logType, __FILE__, __LINE__,                       \
                   cmCTestLog_msg.str().c_str(), suppress);                    \
   } while (false)
-
-#endif
diff --git a/Source/cmCacheManager.cxx b/Source/cmCacheManager.cxx
index 35bd681..95686ea 100644
--- a/Source/cmCacheManager.cxx
+++ b/Source/cmCacheManager.cxx
@@ -578,10 +578,7 @@ cmProp cmCacheManager::CacheEntry::GetProperty(const std::string& prop) const
 bool cmCacheManager::CacheEntry::GetPropertyAsBool(
   const std::string& prop) const
 {
-  if (cmProp value = this->GetProperty(prop)) {
-    return cmIsOn(*value);
-  }
-  return false;
+  return cmIsOn(this->GetProperty(prop));
 }
 
 void cmCacheManager::CacheEntry::SetProperty(const std::string& prop,
diff --git a/Source/cmCacheManager.h b/Source/cmCacheManager.h
index f036258..20d49a8 100644
--- a/Source/cmCacheManager.h
+++ b/Source/cmCacheManager.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCacheManager_h
-#define cmCacheManager_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -210,5 +209,3 @@ private:
   unsigned int CacheMajorVersion = 0;
   unsigned int CacheMinorVersion = 0;
 };
-
-#endif
diff --git a/Source/cmCallVisualStudioMacro.h b/Source/cmCallVisualStudioMacro.h
index 9b5b3a8..795b863 100644
--- a/Source/cmCallVisualStudioMacro.h
+++ b/Source/cmCallVisualStudioMacro.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCallVisualStudioMacro_h
-#define cmCallVisualStudioMacro_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -32,5 +31,3 @@ public:
 protected:
 private:
 };
-
-#endif
diff --git a/Source/cmCheckCustomOutputs.h b/Source/cmCheckCustomOutputs.h
index 9f33d16..2752ed4 100644
--- a/Source/cmCheckCustomOutputs.h
+++ b/Source/cmCheckCustomOutputs.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCheckCustomOutputs_h
-#define cmCheckCustomOutputs_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -14,5 +13,3 @@ class cmExecutionStatus;
 
 bool cmCheckCustomOutputs(const std::vector<std::string>& outputs,
                           cm::string_view keyword, cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCommand.h b/Source/cmCommand.h
index bcb178d..68c56d9 100644
--- a/Source/cmCommand.h
+++ b/Source/cmCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCommand_h
-#define cmCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -96,5 +95,3 @@ public:
 private:
   std::unique_ptr<cmCommand> Command;
 };
-
-#endif
diff --git a/Source/cmCommandArgumentParserHelper.cxx b/Source/cmCommandArgumentParserHelper.cxx
index 87eb91c..e07f7f1 100644
--- a/Source/cmCommandArgumentParserHelper.cxx
+++ b/Source/cmCommandArgumentParserHelper.cxx
@@ -93,7 +93,7 @@ const char* cmCommandArgumentParserHelper::ExpandVariable(const char* var)
   if (this->FileLine >= 0 && strcmp(var, "CMAKE_CURRENT_LIST_LINE") == 0) {
     return this->AddString(std::to_string(this->FileLine));
   }
-  const char* value = this->Makefile->GetDefinition(var);
+  cmProp value = this->Makefile->GetDefinition(var);
   if (!value) {
     this->Makefile->MaybeWarnUninitialized(var, this->FileName);
     if (!this->RemoveEmpty) {
@@ -101,9 +101,9 @@ const char* cmCommandArgumentParserHelper::ExpandVariable(const char* var)
     }
   }
   if (this->EscapeQuotes && value) {
-    return this->AddString(cmEscapeQuotes(value));
+    return this->AddString(cmEscapeQuotes(*value));
   }
-  return this->AddString(value ? value : "");
+  return this->AddString(cmToCStrSafe(value));
 }
 
 const char* cmCommandArgumentParserHelper::ExpandVariableForAt(const char* var)
diff --git a/Source/cmCommandArgumentParserHelper.h b/Source/cmCommandArgumentParserHelper.h
index b46edcb..8ff689e 100644
--- a/Source/cmCommandArgumentParserHelper.h
+++ b/Source/cmCommandArgumentParserHelper.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCommandArgumentParserHelper_h
-#define cmCommandArgumentParserHelper_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -89,5 +88,3 @@ private:
 #define YY_EXTRA_TYPE cmCommandArgumentParserHelper*
 #define YY_DECL                                                               \
   int cmCommandArgument_yylex(YYSTYPE* yylvalp, yyscan_t yyscanner)
-
-#endif
diff --git a/Source/cmCommands.cxx b/Source/cmCommands.cxx
index c94f128..37be542 100644
--- a/Source/cmCommands.cxx
+++ b/Source/cmCommands.cxx
@@ -17,6 +17,7 @@
 #include "cmBreakCommand.h"
 #include "cmBuildCommand.h"
 #include "cmCMakeMinimumRequired.h"
+#include "cmCMakePathCommand.h"
 #include "cmCMakePolicyCommand.h"
 #include "cmCommand.h"
 #include "cmConfigureFileCommand.h"
@@ -120,6 +121,7 @@ void GetScriptingCommands(cmState* state)
 {
   state->AddBuiltinCommand("break", cmBreakCommand);
   state->AddBuiltinCommand("cmake_minimum_required", cmCMakeMinimumRequired);
+  state->AddBuiltinCommand("cmake_path", cmCMakePathCommand);
   state->AddBuiltinCommand("cmake_policy", cmCMakePolicyCommand);
   state->AddBuiltinCommand("configure_file", cmConfigureFileCommand);
   state->AddBuiltinCommand("continue", cmContinueCommand);
diff --git a/Source/cmCommands.h b/Source/cmCommands.h
index 1f8fafb..5605430 100644
--- a/Source/cmCommands.h
+++ b/Source/cmCommands.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCommands_h
-#define cmCommands_h
+#pragma once
 
 class cmState;
 
@@ -13,5 +12,3 @@ class cmState;
 void GetScriptingCommands(cmState* state);
 void GetProjectCommands(cmState* state);
 void GetProjectCommandsInScriptMode(cmState* state);
-
-#endif
diff --git a/Source/cmCommonTargetGenerator.cxx b/Source/cmCommonTargetGenerator.cxx
index 051eff6..2b7c9f6 100644
--- a/Source/cmCommonTargetGenerator.cxx
+++ b/Source/cmCommonTargetGenerator.cxx
@@ -41,7 +41,7 @@ std::vector<std::string> const& cmCommonTargetGenerator::GetConfigNames() const
 const char* cmCommonTargetGenerator::GetFeature(const std::string& feature,
                                                 const std::string& config)
 {
-  return this->GeneratorTarget->GetFeature(feature, config);
+  return this->GeneratorTarget->GetFeature(feature, config)->c_str();
 }
 
 void cmCommonTargetGenerator::AddModuleDefinitionFlag(
@@ -55,7 +55,7 @@ void cmCommonTargetGenerator::AddModuleDefinitionFlag(
   }
 
   // TODO: Create a per-language flag variable.
-  const char* defFileFlag =
+  cmProp defFileFlag =
     this->Makefile->GetDefinition("CMAKE_LINK_DEF_FILE_FLAG");
   if (!defFileFlag) {
     return;
@@ -64,7 +64,7 @@ void cmCommonTargetGenerator::AddModuleDefinitionFlag(
   // Append the flag and value.  Use ConvertToLinkReference to help
   // vs6's "cl -link" pass it to the linker.
   std::string flag =
-    cmStrCat(defFileFlag,
+    cmStrCat(*defFileFlag,
              this->LocalCommonGenerator->ConvertToOutputFormat(
                linkLineComputer->ConvertToLinkReference(mdi->DefFile),
                cmOutputConverter::SHELL));
@@ -270,7 +270,7 @@ void cmCommonTargetGenerator::AppendOSXVerFlag(std::string& flags,
 {
   // Lookup the flag to specify the version.
   std::string fvar = cmStrCat("CMAKE_", lang, "_OSX_", name, "_VERSION_FLAG");
-  const char* flag = this->Makefile->GetDefinition(fvar);
+  cmProp flag = this->Makefile->GetDefinition(fvar);
 
   // Skip if no such flag.
   if (!flag) {
@@ -288,7 +288,7 @@ void cmCommonTargetGenerator::AppendOSXVerFlag(std::string& flags,
   if (major > 0 || minor > 0 || patch > 0) {
     // Append the flag since a non-zero version is specified.
     std::ostringstream vflag;
-    vflag << flag << major << "." << minor << "." << patch;
+    vflag << *flag << major << "." << minor << "." << patch;
     this->LocalCommonGenerator->AppendFlags(flags, vflag.str());
   }
 }
diff --git a/Source/cmCommonTargetGenerator.h b/Source/cmCommonTargetGenerator.h
index c3c3a3a..fba6b0a 100644
--- a/Source/cmCommonTargetGenerator.h
+++ b/Source/cmCommonTargetGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCommonTargetGenerator_h
-#define cmCommonTargetGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -75,5 +74,3 @@ private:
   };
   std::map<std::string, ByConfig> Configs;
 };
-
-#endif
diff --git a/Source/cmComputeComponentGraph.cxx b/Source/cmComputeComponentGraph.cxx
index 81cd878..6591fb1 100644
--- a/Source/cmComputeComponentGraph.cxx
+++ b/Source/cmComputeComponentGraph.cxx
@@ -8,6 +8,12 @@
 cmComputeComponentGraph::cmComputeComponentGraph(Graph const& input)
   : InputGraph(input)
 {
+}
+
+cmComputeComponentGraph::~cmComputeComponentGraph() = default;
+
+void cmComputeComponentGraph::Compute()
+{
   // Identify components.
   this->Tarjan();
 
@@ -17,8 +23,6 @@ cmComputeComponentGraph::cmComputeComponentGraph(Graph const& input)
   this->TransferEdges();
 }
 
-cmComputeComponentGraph::~cmComputeComponentGraph() = default;
-
 void cmComputeComponentGraph::Tarjan()
 {
   int n = static_cast<int>(this->InputGraph.size());
diff --git a/Source/cmComputeComponentGraph.h b/Source/cmComputeComponentGraph.h
index 202888c..1d1d134 100644
--- a/Source/cmComputeComponentGraph.h
+++ b/Source/cmComputeComponentGraph.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmComputeComponentGraph_h
-#define cmComputeComponentGraph_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -31,6 +30,9 @@ public:
   cmComputeComponentGraph(Graph const& input);
   ~cmComputeComponentGraph();
 
+  /** Run the computation.  */
+  void Compute();
+
   /** Get the adjacency list of the component graph.  */
   Graph const& GetComponentGraph() const { return this->ComponentGraph; }
   EdgeList const& GetComponentGraphEdges(int c) const
@@ -75,5 +77,3 @@ private:
 
   // Connected components.
 };
-
-#endif
diff --git a/Source/cmComputeLinkDepends.cxx b/Source/cmComputeLinkDepends.cxx
index e9bf5a5..5341e8d 100644
--- a/Source/cmComputeLinkDepends.cxx
+++ b/Source/cmComputeLinkDepends.cxx
@@ -5,7 +5,6 @@
 #include <algorithm>
 #include <cassert>
 #include <cstdio>
-#include <cstring>
 #include <iterator>
 #include <sstream>
 #include <utility>
@@ -18,6 +17,7 @@
 #include "cmListFileCache.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
@@ -253,13 +253,13 @@ cmComputeLinkDepends::Compute()
   // Compute the final set of link entries.
   // Iterate in reverse order so we can keep only the last occurrence
   // of a shared library.
-  std::set<int> emmitted;
+  std::set<int> emitted;
   for (int i : cmReverseRange(this->FinalLinkOrder)) {
     LinkEntry const& e = this->EntryList[i];
     cmGeneratorTarget const* t = e.Target;
     // Entries that we know the linker will re-use do not need to be repeated.
     bool uniquify = t && t->GetType() == cmStateEnums::SHARED_LIBRARY;
-    if (!uniquify || emmitted.insert(i).second) {
+    if (!uniquify || emitted.insert(i).second) {
       this->FinalLinkEntries.push_back(e);
     }
   }
@@ -315,9 +315,9 @@ int cmComputeLinkDepends::AddLinkEntry(cmLinkItem const& item)
   } else {
     // Look for an old-style <item>_LIB_DEPENDS variable.
     std::string var = cmStrCat(entry.Item.Value, "_LIB_DEPENDS");
-    if (const char* val = this->Makefile->GetDefinition(var)) {
+    if (cmProp val = this->Makefile->GetDefinition(var)) {
       // The item dependencies are known.  Follow them.
-      BFSEntry qe = { index, val };
+      BFSEntry qe = { index, val->c_str() };
       this->BFSQueue.push(qe);
     } else if (!entry.IsFlag) {
       // The item dependencies are not known.  We need to infer them.
@@ -454,10 +454,10 @@ void cmComputeLinkDepends::AddVarLinkEntries(int depender_index,
       // lower.
       if (!haveLLT) {
         std::string var = cmStrCat(d, "_LINK_TYPE");
-        if (const char* val = this->Makefile->GetDefinition(var)) {
-          if (strcmp(val, "debug") == 0) {
+        if (cmProp val = this->Makefile->GetDefinition(var)) {
+          if (*val == "debug") {
             llt = DEBUG_LibraryType;
-          } else if (strcmp(val, "optimized") == 0) {
+          } else if (*val == "optimized") {
             llt = OPTIMIZED_LibraryType;
           }
         }
@@ -626,6 +626,7 @@ void cmComputeLinkDepends::OrderLinkEntires()
   // constraints disallow it.
   this->CCG =
     cm::make_unique<cmComputeComponentGraph>(this->EntryConstraintGraph);
+  this->CCG->Compute();
 
   // The component graph is guaranteed to be acyclic.  Start a DFS
   // from every entry to compute a topological order for the
diff --git a/Source/cmComputeLinkDepends.h b/Source/cmComputeLinkDepends.h
index e806dff..902500a 100644
--- a/Source/cmComputeLinkDepends.h
+++ b/Source/cmComputeLinkDepends.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmComputeLinkDepends_h
-#define cmComputeLinkDepends_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -160,5 +159,3 @@ private:
   bool DebugMode;
   bool OldLinkDirMode;
 };
-
-#endif
diff --git a/Source/cmComputeLinkInformation.cxx b/Source/cmComputeLinkInformation.cxx
index 4c5f57d..4a331fb 100644
--- a/Source/cmComputeLinkInformation.cxx
+++ b/Source/cmComputeLinkInformation.cxx
@@ -4,7 +4,6 @@
 
 #include <algorithm>
 #include <cctype>
-#include <cstring>
 #include <sstream>
 #include <utility>
 
@@ -284,27 +283,28 @@ cmComputeLinkInformation::cmComputeLinkInformation(
       this->Target->GetType() == cmStateEnums::MODULE_LIBRARY) {
     std::string loader_flag_var =
       cmStrCat("CMAKE_SHARED_MODULE_LOADER_", this->LinkLanguage, "_FLAG");
-    this->LoaderFlag = this->Makefile->GetDefinition(loader_flag_var);
+    this->LoaderFlag =
+      cmToCStr(this->Makefile->GetDefinition(loader_flag_var));
   }
 
   // Get options needed to link libraries.
-  if (const char* flag = this->Makefile->GetDefinition(
+  if (cmProp flag = this->Makefile->GetDefinition(
         "CMAKE_" + this->LinkLanguage + "_LINK_LIBRARY_FLAG")) {
-    this->LibLinkFlag = flag;
+    this->LibLinkFlag = *flag;
   } else {
     this->LibLinkFlag =
       this->Makefile->GetSafeDefinition("CMAKE_LINK_LIBRARY_FLAG");
   }
-  if (const char* flag = this->Makefile->GetDefinition(
+  if (cmProp flag = this->Makefile->GetDefinition(
         "CMAKE_" + this->LinkLanguage + "_LINK_LIBRARY_FILE_FLAG")) {
-    this->LibLinkFileFlag = flag;
+    this->LibLinkFileFlag = *flag;
   } else {
     this->LibLinkFileFlag =
       this->Makefile->GetSafeDefinition("CMAKE_LINK_LIBRARY_FILE_FLAG");
   }
-  if (const char* suffix = this->Makefile->GetDefinition(
+  if (cmProp suffix = this->Makefile->GetDefinition(
         "CMAKE_" + this->LinkLanguage + "_LINK_LIBRARY_SUFFIX")) {
-    this->LibLinkSuffix = suffix;
+    this->LibLinkSuffix = *suffix;
   } else {
     this->LibLinkSuffix =
       this->Makefile->GetSafeDefinition("CMAKE_LINK_LIBRARY_SUFFIX");
@@ -515,7 +515,7 @@ bool cmComputeLinkInformation::Compute()
   // Restore the target link type so the correct system runtime
   // libraries are found.
   cmProp lss = this->Target->GetProperty("LINK_SEARCH_END_STATIC");
-  if (lss && cmIsOn(*lss)) {
+  if (cmIsOn(lss)) {
     this->SetCurrentLinkType(LinkStatic);
   } else {
     this->SetCurrentLinkType(this->StartLinkType);
@@ -593,9 +593,9 @@ void cmComputeLinkInformation::AddRuntimeLinkLibrary(std::string const& lang)
   if (runtimeLibrary.empty()) {
     return;
   }
-  if (const char* runtimeLinkOptions = this->Makefile->GetDefinition(
+  if (cmProp runtimeLinkOptions = this->Makefile->GetDefinition(
         "CMAKE_" + lang + "_RUNTIME_LIBRARY_LINK_OPTIONS_" + runtimeLibrary)) {
-    std::vector<std::string> libsVec = cmExpandedList(runtimeLinkOptions);
+    std::vector<std::string> libsVec = cmExpandedList(*runtimeLinkOptions);
     for (std::string const& i : libsVec) {
       if (!cm::contains(this->ImplicitLinkLibs, i)) {
         this->AddItem(i, nullptr);
@@ -609,8 +609,8 @@ void cmComputeLinkInformation::AddImplicitLinkInfo(std::string const& lang)
   // Add libraries for this language that are not implied by the
   // linker language.
   std::string libVar = cmStrCat("CMAKE_", lang, "_IMPLICIT_LINK_LIBRARIES");
-  if (const char* libs = this->Makefile->GetDefinition(libVar)) {
-    std::vector<std::string> libsVec = cmExpandedList(libs);
+  if (cmProp libs = this->Makefile->GetDefinition(libVar)) {
+    std::vector<std::string> libsVec = cmExpandedList(*libs);
     for (std::string const& i : libsVec) {
       if (!cm::contains(this->ImplicitLinkLibs, i)) {
         this->AddItem(i, nullptr);
@@ -621,8 +621,8 @@ void cmComputeLinkInformation::AddImplicitLinkInfo(std::string const& lang)
   // Add linker search paths for this language that are not
   // implied by the linker language.
   std::string dirVar = cmStrCat("CMAKE_", lang, "_IMPLICIT_LINK_DIRECTORIES");
-  if (const char* dirs = this->Makefile->GetDefinition(dirVar)) {
-    std::vector<std::string> dirsVec = cmExpandedList(dirs);
+  if (cmProp dirs = this->Makefile->GetDefinition(dirVar)) {
+    std::vector<std::string> dirsVec = cmExpandedList(*dirs);
     this->OrderLinkerSearchPath->AddLanguageDirectories(dirsVec);
   }
 }
@@ -800,8 +800,8 @@ void cmComputeLinkInformation::ComputeLinkTypeInfo()
   this->LinkTypeEnabled = false;
 
   // Lookup link type selection flags.
-  const char* static_link_type_flag = nullptr;
-  const char* shared_link_type_flag = nullptr;
+  cmProp static_link_type_flag = nullptr;
+  cmProp shared_link_type_flag = nullptr;
   const char* target_type_str = nullptr;
   switch (this->Target->GetType()) {
     case cmStateEnums::EXECUTABLE:
@@ -832,16 +832,15 @@ void cmComputeLinkInformation::ComputeLinkTypeInfo()
 
   // We can support link type switching only if all needed flags are
   // known.
-  if (static_link_type_flag && *static_link_type_flag &&
-      shared_link_type_flag && *shared_link_type_flag) {
+  if (cmNonempty(static_link_type_flag) && cmNonempty(shared_link_type_flag)) {
     this->LinkTypeEnabled = true;
-    this->StaticLinkTypeFlag = static_link_type_flag;
-    this->SharedLinkTypeFlag = shared_link_type_flag;
+    this->StaticLinkTypeFlag = *static_link_type_flag;
+    this->SharedLinkTypeFlag = *shared_link_type_flag;
   }
 
   // Lookup the starting link type from the target (linked statically?).
   cmProp lss = this->Target->GetProperty("LINK_SEARCH_START_STATIC");
-  this->StartLinkType = (lss && cmIsOn(*lss)) ? LinkStatic : LinkShared;
+  this->StartLinkType = cmIsOn(lss) ? LinkStatic : LinkShared;
   this->CurrentLinkType = this->StartLinkType;
 }
 
@@ -849,31 +848,30 @@ void cmComputeLinkInformation::ComputeItemParserInfo()
 {
   // Get possible library name prefixes.
   cmMakefile* mf = this->Makefile;
-  this->AddLinkPrefix(mf->GetDefinition("CMAKE_STATIC_LIBRARY_PREFIX"));
-  this->AddLinkPrefix(mf->GetDefinition("CMAKE_SHARED_LIBRARY_PREFIX"));
+  this->AddLinkPrefix(mf->GetSafeDefinition("CMAKE_STATIC_LIBRARY_PREFIX"));
+  this->AddLinkPrefix(mf->GetSafeDefinition("CMAKE_SHARED_LIBRARY_PREFIX"));
 
   // Import library names should be matched and treated as shared
   // libraries for the purposes of linking.
-  this->AddLinkExtension(mf->GetDefinition("CMAKE_IMPORT_LIBRARY_SUFFIX"),
+  this->AddLinkExtension(mf->GetSafeDefinition("CMAKE_IMPORT_LIBRARY_SUFFIX"),
                          LinkShared);
-  this->AddLinkExtension(mf->GetDefinition("CMAKE_STATIC_LIBRARY_SUFFIX"),
+  this->AddLinkExtension(mf->GetSafeDefinition("CMAKE_STATIC_LIBRARY_SUFFIX"),
                          LinkStatic);
-  this->AddLinkExtension(mf->GetDefinition("CMAKE_SHARED_LIBRARY_SUFFIX"),
+  this->AddLinkExtension(mf->GetSafeDefinition("CMAKE_SHARED_LIBRARY_SUFFIX"),
                          LinkShared);
-  this->AddLinkExtension(mf->GetDefinition("CMAKE_LINK_LIBRARY_SUFFIX"),
+  this->AddLinkExtension(mf->GetSafeDefinition("CMAKE_LINK_LIBRARY_SUFFIX"),
                          LinkUnknown);
-  if (const char* linkSuffixes =
-        mf->GetDefinition("CMAKE_EXTRA_LINK_EXTENSIONS")) {
-    std::vector<std::string> linkSuffixVec = cmExpandedList(linkSuffixes);
+  if (cmProp linkSuffixes = mf->GetDefinition("CMAKE_EXTRA_LINK_EXTENSIONS")) {
+    std::vector<std::string> linkSuffixVec = cmExpandedList(*linkSuffixes);
     for (std::string const& i : linkSuffixVec) {
-      this->AddLinkExtension(i.c_str(), LinkUnknown);
+      this->AddLinkExtension(i, LinkUnknown);
     }
   }
-  if (const char* sharedSuffixes =
+  if (cmProp sharedSuffixes =
         mf->GetDefinition("CMAKE_EXTRA_SHARED_LIBRARY_SUFFIXES")) {
-    std::vector<std::string> sharedSuffixVec = cmExpandedList(sharedSuffixes);
+    std::vector<std::string> sharedSuffixVec = cmExpandedList(*sharedSuffixes);
     for (std::string const& i : sharedSuffixVec) {
-      this->AddLinkExtension(i.c_str(), LinkShared);
+      this->AddLinkExtension(i, LinkShared);
     }
   }
 
@@ -903,7 +901,7 @@ void cmComputeLinkInformation::ComputeItemParserInfo()
 #ifdef CM_COMPUTE_LINK_INFO_DEBUG
   fprintf(stderr, "any regex [%s]\n", reg_any.c_str());
 #endif
-  this->ExtractAnyLibraryName.compile(reg_any.c_str());
+  this->ExtractAnyLibraryName.compile(reg_any);
 
   // Create a regex to match static library names.
   if (!this->StaticLinkExtensions.empty()) {
@@ -912,7 +910,7 @@ void cmComputeLinkInformation::ComputeItemParserInfo()
 #ifdef CM_COMPUTE_LINK_INFO_DEBUG
     fprintf(stderr, "static regex [%s]\n", reg_static.c_str());
 #endif
-    this->ExtractStaticLibraryName.compile(reg_static.c_str());
+    this->ExtractStaticLibraryName.compile(reg_static);
   }
 
   // Create a regex to match shared library names.
@@ -924,20 +922,21 @@ void cmComputeLinkInformation::ComputeItemParserInfo()
 #ifdef CM_COMPUTE_LINK_INFO_DEBUG
     fprintf(stderr, "shared regex [%s]\n", reg_shared.c_str());
 #endif
-    this->ExtractSharedLibraryName.compile(reg_shared.c_str());
+    this->ExtractSharedLibraryName.compile(reg_shared);
   }
 }
 
-void cmComputeLinkInformation::AddLinkPrefix(const char* p)
+void cmComputeLinkInformation::AddLinkPrefix(std::string const& p)
 {
-  if (p && *p) {
+  if (!p.empty()) {
     this->LinkPrefixes.insert(p);
   }
 }
 
-void cmComputeLinkInformation::AddLinkExtension(const char* e, LinkType type)
+void cmComputeLinkInformation::AddLinkExtension(std::string const& e,
+                                                LinkType type)
 {
-  if (e && *e) {
+  if (!e.empty()) {
     if (type == LinkStatic) {
       this->StaticLinkExtensions.emplace_back(e);
     }
@@ -962,7 +961,7 @@ std::string cmComputeLinkInformation::CreateExtensionRegex(
     // Store this extension choice with the "." escaped.
     libext += "\\";
 #if defined(_WIN32) && !defined(__CYGWIN__)
-    libext += this->NoCaseExpression(i.c_str());
+    libext += this->NoCaseExpression(i);
 #else
     libext += i;
 #endif
@@ -980,21 +979,19 @@ std::string cmComputeLinkInformation::CreateExtensionRegex(
   return libext;
 }
 
-std::string cmComputeLinkInformation::NoCaseExpression(const char* str)
+std::string cmComputeLinkInformation::NoCaseExpression(std::string const& str)
 {
   std::string ret;
-  ret.reserve(strlen(str) * 4);
-  const char* s = str;
-  while (*s) {
-    if (*s == '.') {
-      ret += *s;
+  ret.reserve(str.size() * 4);
+  for (char c : str) {
+    if (c == '.') {
+      ret += c;
     } else {
       ret += '[';
-      ret += static_cast<char>(tolower(*s));
-      ret += static_cast<char>(toupper(*s));
+      ret += static_cast<char>(tolower(c));
+      ret += static_cast<char>(toupper(c));
       ret += ']';
     }
-    s++;
   }
   return ret;
 }
@@ -1555,10 +1552,10 @@ void cmComputeLinkInformation::LoadImplicitLinkInfo()
 
   // Append library architecture to all implicit platform directories
   // and add them to the set
-  if (const char* libraryArch =
+  if (cmProp libraryArch =
         this->Makefile->GetDefinition("CMAKE_LIBRARY_ARCHITECTURE")) {
     for (std::string const& i : implicitDirVec) {
-      this->ImplicitLinkDirs.insert(i + "/" + libraryArch);
+      this->ImplicitLinkDirs.insert(i + "/" + *libraryArch);
     }
   }
 
@@ -1688,7 +1685,7 @@ void cmComputeLinkInformation::AddLibraryRuntimeInfo(
   }
 }
 
-static void cmCLI_ExpandListUnique(const char* str,
+static void cmCLI_ExpandListUnique(std::string const& str,
                                    std::vector<std::string>& out,
                                    std::set<std::string>& emitted)
 {
@@ -1735,7 +1732,7 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
   if (use_install_rpath) {
     std::string install_rpath;
     this->Target->GetInstallRPATH(this->Config, install_rpath);
-    cmCLI_ExpandListUnique(install_rpath.c_str(), runtimeDirs, emitted);
+    cmCLI_ExpandListUnique(install_rpath, runtimeDirs, emitted);
   }
   if (use_build_rpath) {
     // Add directories explicitly specified by user
@@ -1743,19 +1740,18 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
     if (this->Target->GetBuildRPATH(this->Config, build_rpath)) {
       // This will not resolve entries to use $ORIGIN, the user is expected to
       // do that if necessary.
-      cmCLI_ExpandListUnique(build_rpath.c_str(), runtimeDirs, emitted);
+      cmCLI_ExpandListUnique(build_rpath, runtimeDirs, emitted);
     }
   }
   if (use_build_rpath || use_link_rpath) {
     std::string rootPath;
-    if (const char* sysrootLink =
+    if (cmProp sysrootLink =
           this->Makefile->GetDefinition("CMAKE_SYSROOT_LINK")) {
-      rootPath = sysrootLink;
+      rootPath = *sysrootLink;
     } else {
       rootPath = this->Makefile->GetSafeDefinition("CMAKE_SYSROOT");
     }
-    const char* stagePath =
-      this->Makefile->GetDefinition("CMAKE_STAGING_PREFIX");
+    cmProp stagePath = this->Makefile->GetDefinition("CMAKE_STAGING_PREFIX");
     std::string const& installPrefix =
       this->Makefile->GetSafeDefinition("CMAKE_INSTALL_PREFIX");
     cmSystemTools::ConvertToUnixSlashes(rootPath);
@@ -1769,8 +1765,8 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
         std::string d = ri;
         if (!rootPath.empty() && cmHasPrefix(d, rootPath)) {
           d.erase(0, rootPath.size());
-        } else if (stagePath && *stagePath && cmHasPrefix(d, stagePath)) {
-          d.erase(0, strlen(stagePath));
+        } else if (cmNonempty(stagePath) && cmHasPrefix(d, *stagePath)) {
+          d.erase(0, (*stagePath).size());
           d = cmStrCat(installPrefix, '/', d);
           cmSystemTools::ConvertToUnixSlashes(d);
         } else if (use_relative_build_rpath) {
@@ -1800,8 +1796,8 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
           std::string d = ri;
           if (!rootPath.empty() && cmHasPrefix(d, rootPath)) {
             d.erase(0, rootPath.size());
-          } else if (stagePath && *stagePath && cmHasPrefix(d, stagePath)) {
-            d.erase(0, strlen(stagePath));
+          } else if (cmNonempty(stagePath) && cmHasPrefix(d, *stagePath)) {
+            d.erase(0, (*stagePath).size());
             d = cmStrCat(installPrefix, '/', d);
             cmSystemTools::ConvertToUnixSlashes(d);
           }
@@ -1823,8 +1819,8 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
         "CMAKE_" + li + "_USE_IMPLICIT_LINK_DIRECTORIES_IN_RUNTIME_PATH";
       if (this->Makefile->IsOn(useVar)) {
         std::string dirVar = "CMAKE_" + li + "_IMPLICIT_LINK_DIRECTORIES";
-        if (const char* dirs = this->Makefile->GetDefinition(dirVar)) {
-          cmCLI_ExpandListUnique(dirs, runtimeDirs, emitted);
+        if (cmProp dirs = this->Makefile->GetDefinition(dirVar)) {
+          cmCLI_ExpandListUnique(*dirs, runtimeDirs, emitted);
         }
       }
     }
@@ -1832,7 +1828,7 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
 
   // Add runtime paths required by the platform to always be
   // present.  This is done even when skipping rpath support.
-  cmCLI_ExpandListUnique(this->RuntimeAlways.c_str(), runtimeDirs, emitted);
+  cmCLI_ExpandListUnique(this->RuntimeAlways, runtimeDirs, emitted);
 }
 
 std::string cmComputeLinkInformation::GetRPathString(bool for_install) const
diff --git a/Source/cmComputeLinkInformation.h b/Source/cmComputeLinkInformation.h
index e50d369..543b6d7 100644
--- a/Source/cmComputeLinkInformation.h
+++ b/Source/cmComputeLinkInformation.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmComputeLinkInformation_h
-#define cmComputeLinkInformation_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -144,11 +143,11 @@ private:
   cmsys::RegularExpression ExtractSharedLibraryName;
   cmsys::RegularExpression ExtractAnyLibraryName;
   std::string SharedRegexString;
-  void AddLinkPrefix(const char* p);
-  void AddLinkExtension(const char* e, LinkType type);
+  void AddLinkPrefix(std::string const& p);
+  void AddLinkExtension(std::string const& e, LinkType type);
   std::string CreateExtensionRegex(std::vector<std::string> const& exts,
                                    LinkType type);
-  std::string NoCaseExpression(const char* str);
+  std::string NoCaseExpression(std::string const& str);
 
   // Handling of link items.
   void AddTargetItem(BT<std::string> const& item,
@@ -209,5 +208,3 @@ private:
                              const cmGeneratorTarget* target);
   void AddLibraryRuntimeInfo(std::string const& fullPath);
 };
-
-#endif
diff --git a/Source/cmComputeTargetDepends.cxx b/Source/cmComputeTargetDepends.cxx
index 41f5346..1f22ce6 100644
--- a/Source/cmComputeTargetDepends.cxx
+++ b/Source/cmComputeTargetDepends.cxx
@@ -17,10 +17,12 @@
 #include "cmMakefile.h"
 #include "cmMessageType.h"
 #include "cmPolicies.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmSourceFile.h"
 #include "cmState.h"
 #include "cmStateTypes.h"
+#include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 #include "cmTarget.h"
 #include "cmTargetDepend.h"
@@ -115,18 +117,32 @@ bool cmComputeTargetDepends::Compute()
   if (this->DebugMode) {
     this->DisplayGraph(this->InitialGraph, "initial");
   }
+  cmComputeComponentGraph ccg1(this->InitialGraph);
+  ccg1.Compute();
+  if (!this->CheckComponents(ccg1)) {
+    return false;
+  }
+
+  // Compute the intermediate graph.
+  this->CollectSideEffects();
+  this->ComputeIntermediateGraph();
+  if (this->DebugMode) {
+    this->DisplaySideEffects();
+    this->DisplayGraph(this->IntermediateGraph, "intermediate");
+  }
 
   // Identify components.
-  cmComputeComponentGraph ccg(this->InitialGraph);
+  cmComputeComponentGraph ccg2(this->IntermediateGraph);
+  ccg2.Compute();
   if (this->DebugMode) {
-    this->DisplayComponents(ccg);
+    this->DisplayComponents(ccg2, "intermediate");
   }
-  if (!this->CheckComponents(ccg)) {
+  if (!this->CheckComponents(ccg2)) {
     return false;
   }
 
   // Compute the final dependency graph.
-  if (!this->ComputeFinalDepends(ccg)) {
+  if (!this->ComputeFinalDepends(ccg2)) {
     return false;
   }
   if (this->DebugMode) {
@@ -184,7 +200,7 @@ void cmComputeTargetDepends::CollectTargetDepends(int depender_index)
 {
   // Get the depender.
   cmGeneratorTarget const* depender = this->Targets[depender_index];
-  if (depender->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+  if (!depender->IsInBuildSystem()) {
     return;
   }
 
@@ -196,18 +212,20 @@ void cmComputeTargetDepends::CollectTargetDepends(int depender_index)
     std::set<cmLinkItem> emitted;
 
     std::vector<std::string> const& configs =
-      depender->Makefile->GetGeneratorConfigs();
+      depender->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
     for (std::string const& it : configs) {
-      cmLinkImplementation const* impl = depender->GetLinkImplementation(it);
-
       // A target should not depend on itself.
       emitted.insert(cmLinkItem(depender, false, cmListFileBacktrace()));
       emitted.insert(cmLinkItem(depender, true, cmListFileBacktrace()));
-      for (cmLinkImplItem const& lib : impl->Libraries) {
-        // Don't emit the same library twice for this target.
-        if (emitted.insert(lib).second) {
-          this->AddTargetDepend(depender_index, lib, true, false);
-          this->AddInterfaceDepends(depender_index, lib, it, emitted);
+
+      if (cmLinkImplementation const* impl =
+            depender->GetLinkImplementation(it)) {
+        for (cmLinkImplItem const& lib : impl->Libraries) {
+          // Don't emit the same library twice for this target.
+          if (emitted.insert(lib).second) {
+            this->AddTargetDepend(depender_index, lib, true, false);
+            this->AddInterfaceDepends(depender_index, lib, it, emitted);
+          }
         }
       }
 
@@ -356,10 +374,9 @@ void cmComputeTargetDepends::AddTargetDepend(
   int depender_index, cmGeneratorTarget const* dependee,
   cmListFileBacktrace const& dependee_backtrace, bool linking, bool cross)
 {
-  if (dependee->IsImported() ||
-      dependee->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
-    // Skip IMPORTED and INTERFACE targets but follow their utility
-    // dependencies.
+  if (!dependee->IsInBuildSystem()) {
+    // Skip targets that are not in the buildsystem but follow their
+    // utility dependencies.
     std::set<cmLinkItem> const& utils = dependee->GetUtilityItems();
     for (cmLinkItem const& i : utils) {
       if (cmGeneratorTarget const* transitive_dependee = i.Target) {
@@ -380,6 +397,111 @@ void cmComputeTargetDepends::AddTargetDepend(
   }
 }
 
+void cmComputeTargetDepends::CollectSideEffects()
+{
+  this->SideEffects.resize(0);
+  this->SideEffects.resize(this->InitialGraph.size());
+
+  int n = static_cast<int>(this->InitialGraph.size());
+  std::set<int> visited;
+  for (int i = 0; i < n; ++i) {
+    this->CollectSideEffectsForTarget(visited, i);
+  }
+}
+
+void cmComputeTargetDepends::CollectSideEffectsForTarget(
+  std::set<int>& visited, int depender_index)
+{
+  if (!visited.count(depender_index)) {
+    auto& se = this->SideEffects[depender_index];
+    visited.insert(depender_index);
+    this->Targets[depender_index]->AppendCustomCommandSideEffects(
+      se.CustomCommandSideEffects);
+    this->Targets[depender_index]->AppendLanguageSideEffects(
+      se.LanguageSideEffects);
+
+    for (auto const& edge : this->InitialGraph[depender_index]) {
+      this->CollectSideEffectsForTarget(visited, edge);
+      auto const& dse = this->SideEffects[edge];
+      se.CustomCommandSideEffects.insert(dse.CustomCommandSideEffects.cbegin(),
+                                         dse.CustomCommandSideEffects.cend());
+      for (auto const& it : dse.LanguageSideEffects) {
+        se.LanguageSideEffects[it.first].insert(it.second.cbegin(),
+                                                it.second.cend());
+      }
+    }
+  }
+}
+
+void cmComputeTargetDepends::ComputeIntermediateGraph()
+{
+  this->IntermediateGraph.resize(0);
+  this->IntermediateGraph.resize(this->InitialGraph.size());
+
+  int n = static_cast<int>(this->InitialGraph.size());
+  for (int i = 0; i < n; ++i) {
+    auto const& initialEdges = this->InitialGraph[i];
+    auto& intermediateEdges = this->IntermediateGraph[i];
+    cmGeneratorTarget const* gt = this->Targets[i];
+    if (gt->GetType() != cmStateEnums::STATIC_LIBRARY &&
+        gt->GetType() != cmStateEnums::OBJECT_LIBRARY) {
+      intermediateEdges = initialEdges;
+    } else {
+      if (cmProp optimizeDependencies =
+            gt->GetProperty("OPTIMIZE_DEPENDENCIES")) {
+        if (cmIsOn(optimizeDependencies)) {
+          this->OptimizeLinkDependencies(gt, intermediateEdges, initialEdges);
+        } else {
+          intermediateEdges = initialEdges;
+        }
+      } else {
+        intermediateEdges = initialEdges;
+      }
+    }
+  }
+}
+
+void cmComputeTargetDepends::OptimizeLinkDependencies(
+  cmGeneratorTarget const* gt, cmGraphEdgeList& outputEdges,
+  cmGraphEdgeList const& inputEdges)
+{
+  std::set<int> emitted;
+  for (auto const& edge : inputEdges) {
+    if (edge.IsStrong()) {
+      // Preserve strong edges
+      outputEdges.push_back(edge);
+    } else {
+      auto const& dse = this->SideEffects[edge];
+
+      // Add edges that have custom command side effects
+      for (cmGeneratorTarget const* dep : dse.CustomCommandSideEffects) {
+        auto index = this->TargetIndex[dep];
+        if (!emitted.count(index)) {
+          emitted.insert(index);
+          outputEdges.push_back(
+            cmGraphEdge(index, false, edge.IsCross(), edge.GetBacktrace()));
+        }
+      }
+
+      // Add edges that have language side effects for languages we
+      // care about
+      for (auto const& lang : gt->GetAllConfigCompileLanguages()) {
+        auto it = dse.LanguageSideEffects.find(lang);
+        if (it != dse.LanguageSideEffects.end()) {
+          for (cmGeneratorTarget const* dep : it->second) {
+            auto index = this->TargetIndex[dep];
+            if (!emitted.count(index)) {
+              emitted.insert(index);
+              outputEdges.push_back(cmGraphEdge(index, false, edge.IsCross(),
+                                                edge.GetBacktrace()));
+            }
+          }
+        }
+      }
+    }
+  }
+}
+
 void cmComputeTargetDepends::DisplayGraph(Graph const& graph,
                                           const std::string& name)
 {
@@ -400,10 +522,39 @@ void cmComputeTargetDepends::DisplayGraph(Graph const& graph,
   fprintf(stderr, "\n");
 }
 
+void cmComputeTargetDepends::DisplaySideEffects()
+{
+  fprintf(stderr, "The side effects are:\n");
+  int n = static_cast<int>(SideEffects.size());
+  for (int depender_index = 0; depender_index < n; ++depender_index) {
+    cmGeneratorTarget const* depender = this->Targets[depender_index];
+    fprintf(stderr, "target %d is [%s]\n", depender_index,
+            depender->GetName().c_str());
+    if (!this->SideEffects[depender_index].CustomCommandSideEffects.empty()) {
+      fprintf(stderr, "  custom commands\n");
+      for (auto const* gt :
+           this->SideEffects[depender_index].CustomCommandSideEffects) {
+        fprintf(stderr, "    from target %d [%s]\n", this->TargetIndex[gt],
+                gt->GetName().c_str());
+      }
+    }
+    for (auto const& it :
+         this->SideEffects[depender_index].LanguageSideEffects) {
+      fprintf(stderr, "  language %s\n", it.first.c_str());
+      for (auto const* gt : it.second) {
+        fprintf(stderr, "    from target %d [%s]\n", this->TargetIndex[gt],
+                gt->GetName().c_str());
+      }
+    }
+  }
+  fprintf(stderr, "\n");
+}
+
 void cmComputeTargetDepends::DisplayComponents(
-  cmComputeComponentGraph const& ccg)
+  cmComputeComponentGraph const& ccg, const std::string& name)
 {
-  fprintf(stderr, "The strongly connected components are:\n");
+  fprintf(stderr, "The strongly connected components for the %s graph are:\n",
+          name.c_str());
   std::vector<NodeList> const& components = ccg.GetComponents();
   int n = static_cast<int>(components.size());
   for (int c = 0; c < n; ++c) {
diff --git a/Source/cmComputeTargetDepends.h b/Source/cmComputeTargetDepends.h
index e0d625f..3517844 100644
--- a/Source/cmComputeTargetDepends.h
+++ b/Source/cmComputeTargetDepends.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmComputeTargetDepends_h
-#define cmComputeTargetDepends_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -42,6 +41,13 @@ public:
                               cmTargetDependSet& deps);
 
 private:
+  struct TargetSideEffects
+  {
+    std::set<cmGeneratorTarget const*> CustomCommandSideEffects;
+    std::map<std::string, std::set<cmGeneratorTarget const*>>
+      LanguageSideEffects;
+  };
+
   void CollectTargets();
   void CollectDepends();
   void CollectTargetDepends(int depender_index);
@@ -50,6 +56,12 @@ private:
   void AddTargetDepend(int depender_index, cmGeneratorTarget const* dependee,
                        cmListFileBacktrace const& dependee_backtrace,
                        bool linking, bool cross);
+  void CollectSideEffects();
+  void CollectSideEffectsForTarget(std::set<int>& visited, int depender_index);
+  void ComputeIntermediateGraph();
+  void OptimizeLinkDependencies(cmGeneratorTarget const* gt,
+                                cmGraphEdgeList& outputEdges,
+                                cmGraphEdgeList const& inputEdges);
   bool ComputeFinalDepends(cmComputeComponentGraph const& ccg);
   void AddInterfaceDepends(int depender_index, cmLinkItem const& dependee_name,
                            const std::string& config,
@@ -74,11 +86,15 @@ private:
   using EdgeList = cmGraphEdgeList;
   using Graph = cmGraphAdjacencyList;
   Graph InitialGraph;
+  Graph IntermediateGraph;
   Graph FinalGraph;
+  std::vector<TargetSideEffects> SideEffects;
   void DisplayGraph(Graph const& graph, const std::string& name);
+  void DisplaySideEffects();
 
   // Deal with connected components.
-  void DisplayComponents(cmComputeComponentGraph const& ccg);
+  void DisplayComponents(cmComputeComponentGraph const& ccg,
+                         const std::string& name);
   bool CheckComponents(cmComputeComponentGraph const& ccg);
   void ComplainAboutBadComponent(cmComputeComponentGraph const& ccg, int c,
                                  bool strong = false);
@@ -88,5 +104,3 @@ private:
   bool IntraComponent(std::vector<int> const& cmap, int c, int i, int* head,
                       std::set<int>& emitted, std::set<int>& visited);
 };
-
-#endif
diff --git a/Source/cmConditionEvaluator.cxx b/Source/cmConditionEvaluator.cxx
index 7a3a3e8..7ada8d8 100644
--- a/Source/cmConditionEvaluator.cxx
+++ b/Source/cmConditionEvaluator.cxx
@@ -4,7 +4,6 @@
 
 #include <cstdio>
 #include <cstdlib>
-#include <cstring>
 #include <functional>
 #include <sstream>
 #include <utility>
@@ -15,6 +14,7 @@
 
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -134,7 +134,7 @@ bool cmConditionEvaluator::IsTrue(
 }
 
 //=========================================================================
-const char* cmConditionEvaluator::GetDefinitionIfUnquoted(
+cmProp cmConditionEvaluator::GetDefinitionIfUnquoted(
   cmExpandedCommandArgument const& argument) const
 {
   if ((this->Policy54Status != cmPolicies::WARN &&
@@ -143,7 +143,7 @@ const char* cmConditionEvaluator::GetDefinitionIfUnquoted(
     return nullptr;
   }
 
-  const char* def = this->Makefile.GetDefinition(argument.GetValue());
+  cmProp def = this->Makefile.GetDefinition(argument.GetValue());
 
   if (def && argument.WasQuoted() &&
       this->Policy54Status == cmPolicies::WARN) {
@@ -165,13 +165,13 @@ const char* cmConditionEvaluator::GetDefinitionIfUnquoted(
 }
 
 //=========================================================================
-const char* cmConditionEvaluator::GetVariableOrString(
+cmProp cmConditionEvaluator::GetVariableOrString(
   const cmExpandedCommandArgument& argument) const
 {
-  const char* def = this->GetDefinitionIfUnquoted(argument);
+  cmProp def = this->GetDefinitionIfUnquoted(argument);
 
   if (!def) {
-    def = argument.c_str();
+    def = &argument.GetValue();
   }
 
   return def;
@@ -231,7 +231,7 @@ bool cmConditionEvaluator::GetBooleanValue(
   // Check for numbers.
   if (!arg.empty()) {
     char* end;
-    double d = strtod(arg.c_str(), &end);
+    double d = strtod(arg.GetValue().c_str(), &end);
     if (*end == '\0') {
       // The whole string is a number.  Use C conversion to bool.
       return static_cast<bool>(d);
@@ -239,7 +239,7 @@ bool cmConditionEvaluator::GetBooleanValue(
   }
 
   // Check definition.
-  const char* def = this->GetDefinitionIfUnquoted(arg);
+  cmProp def = this->GetDefinitionIfUnquoted(arg);
   return !cmIsOff(def);
 }
 
@@ -256,13 +256,13 @@ bool cmConditionEvaluator::GetBooleanValueOld(
     if (arg == "1") {
       return true;
     }
-    const char* def = this->GetDefinitionIfUnquoted(arg);
+    cmProp def = this->GetDefinitionIfUnquoted(arg);
     return !cmIsOff(def);
   }
   // Old GetVariableOrNumber behavior.
-  const char* def = this->GetDefinitionIfUnquoted(arg);
-  if (!def && atoi(arg.c_str())) {
-    def = arg.c_str();
+  cmProp def = this->GetDefinitionIfUnquoted(arg);
+  if (!def && atoi(arg.GetValue().c_str())) {
+    def = &arg.GetValue();
   }
   return !cmIsOff(def);
 }
@@ -434,36 +434,38 @@ bool cmConditionEvaluator::HandleLevel1(cmArgumentList& newArgs, std::string&,
       this->IncrementArguments(newArgs, argP1, argP2);
       // does a file exist
       if (this->IsKeyword(keyEXISTS, *arg) && argP1 != newArgs.end()) {
-        this->HandlePredicate(cmSystemTools::FileExists(argP1->c_str()),
+        this->HandlePredicate(cmSystemTools::FileExists(argP1->GetValue()),
                               reducible, arg, newArgs, argP1, argP2);
       }
       // does a directory with this name exist
       if (this->IsKeyword(keyIS_DIRECTORY, *arg) && argP1 != newArgs.end()) {
-        this->HandlePredicate(cmSystemTools::FileIsDirectory(argP1->c_str()),
-                              reducible, arg, newArgs, argP1, argP2);
+        this->HandlePredicate(
+          cmSystemTools::FileIsDirectory(argP1->GetValue()), reducible, arg,
+          newArgs, argP1, argP2);
       }
       // does a symlink with this name exist
       if (this->IsKeyword(keyIS_SYMLINK, *arg) && argP1 != newArgs.end()) {
-        this->HandlePredicate(cmSystemTools::FileIsSymlink(argP1->c_str()),
+        this->HandlePredicate(cmSystemTools::FileIsSymlink(argP1->GetValue()),
                               reducible, arg, newArgs, argP1, argP2);
       }
       // is the given path an absolute path ?
       if (this->IsKeyword(keyIS_ABSOLUTE, *arg) && argP1 != newArgs.end()) {
-        this->HandlePredicate(cmSystemTools::FileIsFullPath(argP1->c_str()),
+        this->HandlePredicate(cmSystemTools::FileIsFullPath(argP1->GetValue()),
                               reducible, arg, newArgs, argP1, argP2);
       }
       // does a command exist
       if (this->IsKeyword(keyCOMMAND, *arg) && argP1 != newArgs.end()) {
         cmState::Command command =
-          this->Makefile.GetState()->GetCommand(argP1->c_str());
+          this->Makefile.GetState()->GetCommand(argP1->GetValue());
         this->HandlePredicate(command != nullptr, reducible, arg, newArgs,
                               argP1, argP2);
       }
       // does a policy exist
       if (this->IsKeyword(keyPOLICY, *arg) && argP1 != newArgs.end()) {
         cmPolicies::PolicyID pid;
-        this->HandlePredicate(cmPolicies::GetPolicyID(argP1->c_str(), pid),
-                              reducible, arg, newArgs, argP1, argP2);
+        this->HandlePredicate(
+          cmPolicies::GetPolicyID(argP1->GetValue().c_str(), pid), reducible,
+          arg, newArgs, argP1, argP2);
       }
       // does a target exist
       if (this->IsKeyword(keyTARGET, *arg) && argP1 != newArgs.end()) {
@@ -475,7 +477,7 @@ bool cmConditionEvaluator::HandleLevel1(cmArgumentList& newArgs, std::string&,
       if (this->Policy64Status != cmPolicies::OLD &&
           this->Policy64Status != cmPolicies::WARN) {
         if (this->IsKeyword(keyTEST, *arg) && argP1 != newArgs.end()) {
-          const cmTest* haveTest = this->Makefile.GetTest(argP1->c_str());
+          const cmTest* haveTest = this->Makefile.GetTest(argP1->GetValue());
           this->HandlePredicate(haveTest != nullptr, reducible, arg, newArgs,
                                 argP1, argP2);
         }
@@ -522,8 +524,8 @@ bool cmConditionEvaluator::HandleLevel2(cmArgumentList& newArgs,
 {
   int reducible;
   std::string def_buf;
-  const char* def;
-  const char* def2;
+  cmProp def;
+  cmProp def2;
   do {
     reducible = 0;
     auto arg = newArgs.begin();
@@ -534,15 +536,16 @@ bool cmConditionEvaluator::HandleLevel2(cmArgumentList& newArgs,
       this->IncrementArguments(newArgs, argP1, argP2);
       if (argP1 != newArgs.end() && argP2 != newArgs.end() &&
           IsKeyword(keyMATCHES, *argP1)) {
-        def = this->GetVariableOrString(*arg);
-        if (def != arg->c_str() // yes, we compare the pointer value
-            && cmHasLiteralPrefix(arg->GetValue(), "CMAKE_MATCH_")) {
+        def = this->GetDefinitionIfUnquoted(*arg);
+        if (!def) {
+          def = &arg->GetValue();
+        } else if (cmHasLiteralPrefix(arg->GetValue(), "CMAKE_MATCH_")) {
           // The string to match is owned by our match result variables.
           // Move it to our own buffer before clearing them.
-          def_buf = def;
-          def = def_buf.c_str();
+          def_buf = *def;
+          def = &def_buf;
         }
-        const char* rex = argP2->c_str();
+        const std::string& rex = argP2->GetValue();
         this->Makefile.ClearMatches();
         cmsys::RegularExpression regEntry;
         if (!regEntry.compile(rex)) {
@@ -552,7 +555,7 @@ bool cmConditionEvaluator::HandleLevel2(cmArgumentList& newArgs,
           status = MessageType::FATAL_ERROR;
           return false;
         }
-        if (regEntry.find(def)) {
+        if (regEntry.find(*def)) {
           this->Makefile.StoreMatches(regEntry);
           *arg = cmExpandedCommandArgument("1", true);
         } else {
@@ -584,7 +587,8 @@ bool cmConditionEvaluator::HandleLevel2(cmArgumentList& newArgs,
         double lhs;
         double rhs;
         bool result;
-        if (sscanf(def, "%lg", &lhs) != 1 || sscanf(def2, "%lg", &rhs) != 1) {
+        if (sscanf(def->c_str(), "%lg", &lhs) != 1 ||
+            sscanf(def2->c_str(), "%lg", &rhs) != 1) {
           result = false;
         } else if (*(argP1) == keyLESS) {
           result = (lhs < rhs);
@@ -608,7 +612,7 @@ bool cmConditionEvaluator::HandleLevel2(cmArgumentList& newArgs,
            this->IsKeyword(keySTREQUAL, *argP1))) {
         def = this->GetVariableOrString(*arg);
         def2 = this->GetVariableOrString(*argP2);
-        int val = strcmp(def, def2);
+        int val = (*def).compare(*def2);
         bool result;
         if (*(argP1) == keySTRLESS) {
           result = (val < 0);
@@ -645,7 +649,8 @@ bool cmConditionEvaluator::HandleLevel2(cmArgumentList& newArgs,
         } else { // version_equal
           op = cmSystemTools::OP_EQUAL;
         }
-        bool result = cmSystemTools::VersionCompare(op, def, def2);
+        bool result =
+          cmSystemTools::VersionCompare(op, def->c_str(), def2->c_str());
         this->HandleBinaryOp(result, reducible, arg, newArgs, argP1, argP2);
       }
 
@@ -670,9 +675,8 @@ bool cmConditionEvaluator::HandleLevel2(cmArgumentList& newArgs,
           def2 = this->Makefile.GetDefinition(argP2->GetValue());
 
           if (def2) {
-            std::vector<std::string> list = cmExpandedList(def2, true);
-
-            result = cm::contains(list, def);
+            std::vector<std::string> list = cmExpandedList(*def2, true);
+            result = cm::contains(list, *def);
           }
 
           this->HandleBinaryOp(result, reducible, arg, newArgs, argP1, argP2);
diff --git a/Source/cmConditionEvaluator.h b/Source/cmConditionEvaluator.h
index 082534c..a4cedff 100644
--- a/Source/cmConditionEvaluator.h
+++ b/Source/cmConditionEvaluator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmConditionEvaluator_h
-#define cmConditionEvaluator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -13,6 +12,7 @@
 #include "cmListFileCache.h"
 #include "cmMessageType.h"
 #include "cmPolicies.h"
+#include "cmProperty.h"
 
 class cmMakefile;
 
@@ -32,11 +32,10 @@ public:
 
 private:
   // Filter the given variable definition based on policy CMP0054.
-  const char* GetDefinitionIfUnquoted(
+  cmProp GetDefinitionIfUnquoted(
     const cmExpandedCommandArgument& argument) const;
 
-  const char* GetVariableOrString(
-    const cmExpandedCommandArgument& argument) const;
+  cmProp GetVariableOrString(const cmExpandedCommandArgument& argument) const;
 
   bool IsKeyword(std::string const& keyword,
                  cmExpandedCommandArgument& argument) const;
@@ -87,5 +86,3 @@ private:
   cmPolicies::PolicyStatus Policy57Status;
   cmPolicies::PolicyStatus Policy64Status;
 };
-
-#endif
diff --git a/Source/cmConfigure.cmake.h.in b/Source/cmConfigure.cmake.h.in
index 4de1c5d..ceb2a32 100644
--- a/Source/cmConfigure.cmake.h.in
+++ b/Source/cmConfigure.cmake.h.in
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmConfigure_h
-#define cmConfigure_h
+#pragma once
 
 #include "cmsys/Configure.hxx" // IWYU pragma: export
 
@@ -19,7 +18,6 @@
 #cmakedefine HAVE_UNSETENV
 #cmakedefine CMAKE_USE_ELF_PARSER
 #cmakedefine CMAKE_USE_MACH_PARSER
-#cmakedefine CMake_HAVE_CXX_MAKE_UNIQUE
 #define CMake_DEFAULT_RECURSION_LIMIT @CMake_DEFAULT_RECURSION_LIMIT@
 #define CMAKE_BIN_DIR "/@CMAKE_BIN_DIR@"
 #define CMAKE_DATA_DIR "/@CMAKE_DATA_DIR@"
@@ -29,5 +27,3 @@
 #if defined(_WIN32) && !defined(NOMINMAX)
 #  define NOMINMAX
 #endif
-
-#endif
diff --git a/Source/cmConfigureFileCommand.cxx b/Source/cmConfigureFileCommand.cxx
index 5b3045d..68322cc 100644
--- a/Source/cmConfigureFileCommand.cxx
+++ b/Source/cmConfigureFileCommand.cxx
@@ -60,6 +60,7 @@ bool cmConfigureFileCommand(std::vector<std::string> const& args,
   }
   bool copyOnly = false;
   bool escapeQuotes = false;
+  bool use_source_permissions = true;
 
   static std::set<cm::string_view> noopOptions = {
     /* Legacy.  */
@@ -87,6 +88,8 @@ bool cmConfigureFileCommand(std::vector<std::string> const& args,
       escapeQuotes = true;
     } else if (args[i] == "@ONLY") {
       atOnly = true;
+    } else if (args[i] == "NO_SOURCE_PERMISSIONS") {
+      use_source_permissions = false;
     } else if (noopOptions.find(args[i]) != noopOptions.end()) {
       /* Ignore no-op options.  */
     } else {
@@ -102,7 +105,8 @@ bool cmConfigureFileCommand(std::vector<std::string> const& args,
   }
 
   if (!status.GetMakefile().ConfigureFile(
-        inputFile, outputFile, copyOnly, atOnly, escapeQuotes, newLineStyle)) {
+        inputFile, outputFile, copyOnly, atOnly, escapeQuotes,
+        use_source_permissions, newLineStyle)) {
     status.SetError("Problem configuring file");
     return false;
   }
diff --git a/Source/cmConfigureFileCommand.h b/Source/cmConfigureFileCommand.h
index c7f95b8..009c145 100644
--- a/Source/cmConfigureFileCommand.h
+++ b/Source/cmConfigureFileCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmConfigureFileCommand_h
-#define cmConfigureFileCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,4 +11,3 @@ class cmExecutionStatus;
 
 bool cmConfigureFileCommand(std::vector<std::string> const& args,
                             cmExecutionStatus& status);
-#endif
diff --git a/Source/cmContinueCommand.h b/Source/cmContinueCommand.h
index ff903aa..29a219f 100644
--- a/Source/cmContinueCommand.h
+++ b/Source/cmContinueCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmContinueCommand_h
-#define cmContinueCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -17,5 +16,3 @@ class cmExecutionStatus;
  */
 bool cmContinueCommand(std::vector<std::string> const& args,
                        cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCoreTryCompile.cxx b/Source/cmCoreTryCompile.cxx
index 8550d04..77a6d4b 100644
--- a/Source/cmCoreTryCompile.cxx
+++ b/Source/cmCoreTryCompile.cxx
@@ -18,6 +18,7 @@
 #include "cmMessageType.h"
 #include "cmOutputConverter.h"
 #include "cmPolicies.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -25,77 +26,208 @@
 #include "cmVersion.h"
 #include "cmake.h"
 
-static std::string const kCMAKE_C_COMPILER_EXTERNAL_TOOLCHAIN =
-  "CMAKE_C_COMPILER_EXTERNAL_TOOLCHAIN";
-static std::string const kCMAKE_C_COMPILER_TARGET = "CMAKE_C_COMPILER_TARGET";
-static std::string const kCMAKE_C_LINK_NO_PIE_SUPPORTED =
-  "CMAKE_C_LINK_NO_PIE_SUPPORTED";
-static std::string const kCMAKE_C_LINK_PIE_SUPPORTED =
-  "CMAKE_C_LINK_PIE_SUPPORTED";
-static std::string const kCMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN =
-  "CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN";
-static std::string const kCMAKE_CXX_COMPILER_TARGET =
-  "CMAKE_CXX_COMPILER_TARGET";
-static std::string const kCMAKE_CXX_LINK_NO_PIE_SUPPORTED =
-  "CMAKE_CXX_LINK_NO_PIE_SUPPORTED";
-static std::string const kCMAKE_CXX_LINK_PIE_SUPPORTED =
-  "CMAKE_CXX_LINK_PIE_SUPPORTED";
-static std::string const kCMAKE_CUDA_ARCHITECTURES =
-  "CMAKE_CUDA_ARCHITECTURES";
-static std::string const kCMAKE_CUDA_COMPILER_TARGET =
-  "CMAKE_CUDA_COMPILER_TARGET";
-static std::string const kCMAKE_CUDA_RUNTIME_LIBRARY =
-  "CMAKE_CUDA_RUNTIME_LIBRARY";
-static std::string const kCMAKE_ENABLE_EXPORTS = "CMAKE_ENABLE_EXPORTS";
-static std::string const kCMAKE_LINK_SEARCH_END_STATIC =
+namespace {
+class LanguageStandardState
+{
+public:
+  LanguageStandardState(std::string&& lang)
+    : IsEnabled(false)
+    , DidStandard(false)
+    , DidStandardRequired(false)
+    , DidExtensions(false)
+    , StandardFlag(lang + "_STANDARD")
+    , RequiredFlag(lang + "_STANDARD_REQUIRED")
+    , ExtensionFlag(lang + "_EXTENSIONS")
+  {
+  }
+
+  void Enabled(bool isEnabled) { this->IsEnabled = isEnabled; }
+
+  bool UpdateIfMatches(std::vector<std::string> const& argv, size_t& index)
+  {
+    bool updated = false;
+    if (argv[index] == this->StandardFlag) {
+      this->DidStandard = true;
+      this->StandardValue = argv[++index];
+      updated = true;
+    } else if (argv[index] == this->RequiredFlag) {
+      this->DidStandardRequired = true;
+      this->RequiredValue = argv[++index];
+      updated = true;
+    } else if (argv[index] == this->ExtensionFlag) {
+      this->DidExtensions = true;
+      this->ExtensionValue = argv[++index];
+      updated = true;
+    }
+    return updated;
+  }
+
+  bool Validate(cmMakefile* const makefile) const
+  {
+    if (this->DidStandard) {
+      makefile->IssueMessage(
+        MessageType::FATAL_ERROR,
+        cmStrCat(this->StandardFlag,
+                 " allowed only in source file signature."));
+      return false;
+    }
+    if (this->DidStandardRequired) {
+      makefile->IssueMessage(
+        MessageType::FATAL_ERROR,
+        cmStrCat(this->RequiredFlag,
+                 " allowed only in source file signature."));
+      return false;
+    }
+    if (this->DidExtensions) {
+      makefile->IssueMessage(
+        MessageType::FATAL_ERROR,
+        cmStrCat(this->ExtensionFlag,
+                 " allowed only in source file signature."));
+      return false;
+    }
+
+    return true;
+  }
+
+  bool DidNone() const
+  {
+    return !this->DidStandard && !this->DidStandardRequired &&
+      !this->DidExtensions;
+  }
+
+  void LoadUnsetPropertyValues(cmMakefile* const makefile, bool honorStandard,
+                               bool warnCMP0067,
+                               std::vector<std::string>& warnCMP0067Variables)
+  {
+    if (!this->IsEnabled) {
+      return;
+    }
+
+    auto lookupStdVar = [&](std::string const& var) -> std::string {
+      std::string value = makefile->GetSafeDefinition(var);
+      if (warnCMP0067 && !value.empty()) {
+        value.clear();
+        warnCMP0067Variables.push_back(var);
+      }
+      return value;
+    };
+
+    if (honorStandard || warnCMP0067) {
+      if (!this->DidStandard) {
+        this->StandardValue =
+          lookupStdVar(cmStrCat("CMAKE_", this->StandardFlag));
+      }
+      if (!this->DidStandardRequired) {
+        this->RequiredValue =
+          lookupStdVar(cmStrCat("CMAKE_", this->RequiredFlag));
+      }
+      if (!this->DidExtensions) {
+        this->ExtensionValue =
+          lookupStdVar(cmStrCat("CMAKE_", this->ExtensionFlag));
+      }
+    }
+  }
+
+  void WriteProperties(FILE* fout, std::string const& targetName) const
+  {
+    if (!this->IsEnabled) {
+      return;
+    }
+
+    auto writeProp = [&](std::string const& prop, std::string const& value) {
+      fprintf(fout, "set_property(TARGET %s PROPERTY %s %s)\n",
+              targetName.c_str(),
+              cmOutputConverter::EscapeForCMake(prop).c_str(),
+              cmOutputConverter::EscapeForCMake(value).c_str());
+    };
+
+    if (!this->StandardValue.empty()) {
+      writeProp(this->StandardFlag, this->StandardValue);
+    }
+    if (!this->RequiredValue.empty()) {
+      writeProp(this->RequiredFlag, this->RequiredValue);
+    }
+    if (!this->ExtensionValue.empty()) {
+      writeProp(this->ExtensionFlag, this->ExtensionValue);
+    }
+  }
+
+private:
+  bool IsEnabled;
+  bool DidStandard;
+  bool DidStandardRequired;
+  bool DidExtensions;
+
+  std::string StandardFlag;
+  std::string RequiredFlag;
+  std::string ExtensionFlag;
+
+  std::string StandardValue;
+  std::string RequiredValue;
+  std::string ExtensionValue;
+};
+
+constexpr size_t lang_property_start = 0;
+constexpr size_t lang_property_size = 4;
+constexpr size_t pie_property_start = 4;
+constexpr size_t pie_property_size = 2;
+#define SETUP_LANGUAGE(name, lang)                                            \
+  static const std::string name[lang_property_size + pie_property_size + 1] = \
+    { "CMAKE_" #lang "_COMPILER_EXTERNAL_TOOLCHAIN",                          \
+      "CMAKE_" #lang "_COMPILER_TARGET",                                      \
+      "CMAKE_" #lang "_LINK_NO_PIE_SUPPORTED",                                \
+      "CMAKE_" #lang "_PIE_SUPPORTED", "" }
+
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(c_properties, C);
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(cxx_properties, CXX);
+
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(cuda_properties, CUDA);
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(fortran_properties, Fortran);
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(objc_properties, OBJC);
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(objcxx_properties, OBJCXX);
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(ispc_properties, ISPC);
+// NOLINTNEXTLINE(bugprone-suspicious-missing-comma)
+SETUP_LANGUAGE(swift_properties, Swift);
+#undef SETUP_LANGUAGE
+
+std::string const kCMAKE_CUDA_ARCHITECTURES = "CMAKE_CUDA_ARCHITECTURES";
+std::string const kCMAKE_CUDA_RUNTIME_LIBRARY = "CMAKE_CUDA_RUNTIME_LIBRARY";
+std::string const kCMAKE_ENABLE_EXPORTS = "CMAKE_ENABLE_EXPORTS";
+std::string const kCMAKE_ISPC_INSTRUCTION_SETS = "CMAKE_ISPC_INSTRUCTION_SETS";
+std::string const kCMAKE_LINK_SEARCH_END_STATIC =
   "CMAKE_LINK_SEARCH_END_STATIC";
-static std::string const kCMAKE_LINK_SEARCH_START_STATIC =
+std::string const kCMAKE_LINK_SEARCH_START_STATIC =
   "CMAKE_LINK_SEARCH_START_STATIC";
-static std::string const kCMAKE_MSVC_RUNTIME_LIBRARY_DEFAULT =
+std::string const kCMAKE_MSVC_RUNTIME_LIBRARY_DEFAULT =
   "CMAKE_MSVC_RUNTIME_LIBRARY_DEFAULT";
-static std::string const kCMAKE_OSX_ARCHITECTURES = "CMAKE_OSX_ARCHITECTURES";
-static std::string const kCMAKE_OSX_DEPLOYMENT_TARGET =
-  "CMAKE_OSX_DEPLOYMENT_TARGET";
-static std::string const kCMAKE_OSX_SYSROOT = "CMAKE_OSX_SYSROOT";
-static std::string const kCMAKE_APPLE_ARCH_SYSROOTS =
-  "CMAKE_APPLE_ARCH_SYSROOTS";
-static std::string const kCMAKE_POSITION_INDEPENDENT_CODE =
+std::string const kCMAKE_OSX_ARCHITECTURES = "CMAKE_OSX_ARCHITECTURES";
+std::string const kCMAKE_OSX_DEPLOYMENT_TARGET = "CMAKE_OSX_DEPLOYMENT_TARGET";
+std::string const kCMAKE_OSX_SYSROOT = "CMAKE_OSX_SYSROOT";
+std::string const kCMAKE_APPLE_ARCH_SYSROOTS = "CMAKE_APPLE_ARCH_SYSROOTS";
+std::string const kCMAKE_POSITION_INDEPENDENT_CODE =
   "CMAKE_POSITION_INDEPENDENT_CODE";
-static std::string const kCMAKE_SYSROOT = "CMAKE_SYSROOT";
-static std::string const kCMAKE_SYSROOT_COMPILE = "CMAKE_SYSROOT_COMPILE";
-static std::string const kCMAKE_SYSROOT_LINK = "CMAKE_SYSROOT_LINK";
-static std::string const kCMAKE_Swift_COMPILER_TARGET =
-  "CMAKE_Swift_COMPILER_TARGET";
-static std::string const kCMAKE_TRY_COMPILE_OSX_ARCHITECTURES =
+std::string const kCMAKE_SYSROOT = "CMAKE_SYSROOT";
+std::string const kCMAKE_SYSROOT_COMPILE = "CMAKE_SYSROOT_COMPILE";
+std::string const kCMAKE_SYSROOT_LINK = "CMAKE_SYSROOT_LINK";
+std::string const kCMAKE_TRY_COMPILE_OSX_ARCHITECTURES =
   "CMAKE_TRY_COMPILE_OSX_ARCHITECTURES";
-static std::string const kCMAKE_TRY_COMPILE_PLATFORM_VARIABLES =
+std::string const kCMAKE_TRY_COMPILE_PLATFORM_VARIABLES =
   "CMAKE_TRY_COMPILE_PLATFORM_VARIABLES";
-static std::string const kCMAKE_WARN_DEPRECATED = "CMAKE_WARN_DEPRECATED";
+std::string const kCMAKE_WARN_DEPRECATED = "CMAKE_WARN_DEPRECATED";
 
 /* GHS Multi platform variables */
-static std::set<std::string> ghs_platform_vars{
+std::set<std::string> const ghs_platform_vars{
   "GHS_TARGET_PLATFORM", "GHS_PRIMARY_TARGET", "GHS_TOOLSET_ROOT",
   "GHS_OS_ROOT",         "GHS_OS_DIR",         "GHS_BSP_NAME",
   "GHS_OS_DIR_OPTION"
 };
-
-static void writeProperty(FILE* fout, std::string const& targetName,
-                          std::string const& prop, std::string const& value)
-{
-  fprintf(fout, "set_property(TARGET %s PROPERTY %s %s)\n", targetName.c_str(),
-          cmOutputConverter::EscapeForCMake(prop).c_str(),
-          cmOutputConverter::EscapeForCMake(value).c_str());
-}
-
-std::string cmCoreTryCompile::LookupStdVar(std::string const& var,
-                                           bool warnCMP0067)
-{
-  std::string value = this->Makefile->GetSafeDefinition(var);
-  if (warnCMP0067 && !value.empty()) {
-    value.clear();
-    this->WarnCMP0067.push_back(var);
-  }
-  return value;
 }
 
 int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
@@ -107,9 +239,8 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
   this->SrcFileSignature = true;
 
   cmStateEnums::TargetType targetType = cmStateEnums::EXECUTABLE;
-  const std::string* tt =
-    this->Makefile->GetDef("CMAKE_TRY_COMPILE_TARGET_TYPE");
-  if (!isTryRun && tt && !tt->empty()) {
+  cmProp tt = this->Makefile->GetDefinition("CMAKE_TRY_COMPILE_TARGET_TYPE");
+  if (!isTryRun && cmNonempty(tt)) {
     if (*tt == cmState::GetTargetTypeName(cmStateEnums::EXECUTABLE)) {
       targetType = cmStateEnums::EXECUTABLE;
     } else if (*tt ==
@@ -137,21 +268,11 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
   std::string outputVariable;
   std::string copyFile;
   std::string copyFileError;
-  std::string cStandard;
-  std::string objcStandard;
-  std::string cxxStandard;
-  std::string objcxxStandard;
-  std::string cudaStandard;
-  std::string cStandardRequired;
-  std::string cxxStandardRequired;
-  std::string objcStandardRequired;
-  std::string objcxxStandardRequired;
-  std::string cudaStandardRequired;
-  std::string cExtensions;
-  std::string cxxExtensions;
-  std::string objcExtensions;
-  std::string objcxxExtensions;
-  std::string cudaExtensions;
+  LanguageStandardState cState("C");
+  LanguageStandardState cudaState("CUDA");
+  LanguageStandardState cxxState("CXX");
+  LanguageStandardState objcState("OBJC");
+  LanguageStandardState objcxxState("OBJCXX");
   std::vector<std::string> targets;
   std::vector<std::string> linkOptions;
   std::string libsToLink = " ";
@@ -160,21 +281,6 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
   bool didOutputVariable = false;
   bool didCopyFile = false;
   bool didCopyFileError = false;
-  bool didCStandard = false;
-  bool didCxxStandard = false;
-  bool didObjCStandard = false;
-  bool didObjCxxStandard = false;
-  bool didCudaStandard = false;
-  bool didCStandardRequired = false;
-  bool didCxxStandardRequired = false;
-  bool didObjCStandardRequired = false;
-  bool didObjCxxStandardRequired = false;
-  bool didCudaStandardRequired = false;
-  bool didCExtensions = false;
-  bool didCxxExtensions = false;
-  bool didObjCExtensions = false;
-  bool didObjCxxExtensions = false;
-  bool didCudaExtensions = false;
   bool useSources = argv[2] == "SOURCES";
   std::vector<std::string> sources;
 
@@ -188,21 +294,6 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
     DoingOutputVariable,
     DoingCopyFile,
     DoingCopyFileError,
-    DoingCStandard,
-    DoingCxxStandard,
-    DoingObjCStandard,
-    DoingObjCxxStandard,
-    DoingCudaStandard,
-    DoingCStandardRequired,
-    DoingCxxStandardRequired,
-    DoingObjCStandardRequired,
-    DoingObjCxxStandardRequired,
-    DoingCudaStandardRequired,
-    DoingCExtensions,
-    DoingCxxExtensions,
-    DoingObjCExtensions,
-    DoingObjCxxExtensions,
-    DoingCudaExtensions,
     DoingSources,
     DoingCMakeInternal
   };
@@ -226,51 +317,12 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
     } else if (argv[i] == "COPY_FILE_ERROR") {
       doing = DoingCopyFileError;
       didCopyFileError = true;
-    } else if (argv[i] == "C_STANDARD") {
-      doing = DoingCStandard;
-      didCStandard = true;
-    } else if (argv[i] == "CXX_STANDARD") {
-      doing = DoingCxxStandard;
-      didCxxStandard = true;
-    } else if (argv[i] == "OBJC_STANDARD") {
-      doing = DoingObjCStandard;
-      didObjCStandard = true;
-    } else if (argv[i] == "OBJCXX_STANDARD") {
-      doing = DoingObjCxxStandard;
-      didObjCxxStandard = true;
-    } else if (argv[i] == "CUDA_STANDARD") {
-      doing = DoingCudaStandard;
-      didCudaStandard = true;
-    } else if (argv[i] == "C_STANDARD_REQUIRED") {
-      doing = DoingCStandardRequired;
-      didCStandardRequired = true;
-    } else if (argv[i] == "CXX_STANDARD_REQUIRED") {
-      doing = DoingCxxStandardRequired;
-      didCxxStandardRequired = true;
-    } else if (argv[i] == "OBJC_STANDARD_REQUIRED") {
-      doing = DoingObjCStandardRequired;
-      didObjCStandardRequired = true;
-    } else if (argv[i] == "OBJCXX_STANDARD_REQUIRED") {
-      doing = DoingObjCxxStandardRequired;
-      didObjCxxStandardRequired = true;
-    } else if (argv[i] == "CUDA_STANDARD_REQUIRED") {
-      doing = DoingCudaStandardRequired;
-      didCudaStandardRequired = true;
-    } else if (argv[i] == "C_EXTENSIONS") {
-      doing = DoingCExtensions;
-      didCExtensions = true;
-    } else if (argv[i] == "CXX_EXTENSIONS") {
-      doing = DoingCxxExtensions;
-      didCxxExtensions = true;
-    } else if (argv[i] == "OBJC_EXTENSIONS") {
-      doing = DoingObjCExtensions;
-      didObjCExtensions = true;
-    } else if (argv[i] == "OBJCXX_EXTENSIONS") {
-      doing = DoingObjCxxExtensions;
-      didObjCxxExtensions = true;
-    } else if (argv[i] == "CUDA_EXTENSIONS") {
-      doing = DoingCudaExtensions;
-      didCudaExtensions = true;
+    } else if (cState.UpdateIfMatches(argv, i) ||
+               cxxState.UpdateIfMatches(argv, i) ||
+               cudaState.UpdateIfMatches(argv, i) ||
+               objcState.UpdateIfMatches(argv, i) ||
+               objcxxState.UpdateIfMatches(argv, i)) {
+      continue;
     } else if (argv[i] == "__CMAKE_INTERNAL") {
       doing = DoingCMakeInternal;
     } else if (doing == DoingCMakeFlags) {
@@ -315,51 +367,6 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
     } else if (doing == DoingCopyFileError) {
       copyFileError = argv[i];
       doing = DoingNone;
-    } else if (doing == DoingCStandard) {
-      cStandard = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCxxStandard) {
-      cxxStandard = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingObjCStandard) {
-      objcStandard = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingObjCxxStandard) {
-      objcxxStandard = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCudaStandard) {
-      cudaStandard = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCStandardRequired) {
-      cStandardRequired = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCxxStandardRequired) {
-      cxxStandardRequired = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingObjCStandardRequired) {
-      objcStandardRequired = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingObjCxxStandardRequired) {
-      objcxxStandardRequired = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCudaStandardRequired) {
-      cudaStandardRequired = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCExtensions) {
-      cExtensions = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCxxExtensions) {
-      cxxExtensions = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingObjCExtensions) {
-      objcExtensions = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingObjCxxExtensions) {
-      objcxxExtensions = argv[i];
-      doing = DoingNone;
-    } else if (doing == DoingCudaExtensions) {
-      cudaExtensions = argv[i];
-      doing = DoingNone;
     } else if (doing == DoingSources) {
       sources.push_back(argv[i]);
     } else if (doing == DoingCMakeInternal) {
@@ -411,59 +418,22 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
     return -1;
   }
 
-  if (didCStandard && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "C_STANDARD allowed only in source file signature.");
-    return -1;
-  }
-  if (didCxxStandard && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "CXX_STANDARD allowed only in source file signature.");
-    return -1;
-  }
-  if (didCudaStandard && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "CUDA_STANDARD allowed only in source file signature.");
-    return -1;
-  }
-  if (didCStandardRequired && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "C_STANDARD_REQUIRED allowed only in source file signature.");
-    return -1;
-  }
-  if (didCxxStandardRequired && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "CXX_STANDARD_REQUIRED allowed only in source file signature.");
-    return -1;
-  }
-  if (didCudaStandardRequired && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "CUDA_STANDARD_REQUIRED allowed only in source file signature.");
-    return -1;
-  }
-  if (didCExtensions && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "C_EXTENSIONS allowed only in source file signature.");
-    return -1;
-  }
-  if (didCxxExtensions && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "CXX_EXTENSIONS allowed only in source file signature.");
-    return -1;
-  }
-  if (didCudaExtensions && !this->SrcFileSignature) {
-    this->Makefile->IssueMessage(
-      MessageType::FATAL_ERROR,
-      "CUDA_EXTENSIONS allowed only in source file signature.");
-    return -1;
+  if (!this->SrcFileSignature) {
+    if (!cState.Validate(this->Makefile)) {
+      return -1;
+    }
+    if (!cudaState.Validate(this->Makefile)) {
+      return -1;
+    }
+    if (!cxxState.Validate(this->Makefile)) {
+      return -1;
+    }
+    if (!objcState.Validate(this->Makefile)) {
+      return -1;
+    }
+    if (!objcxxState.Validate(this->Makefile)) {
+      return -1;
+    }
   }
 
   // compute the binary dir when TRY_COMPILE is called with a src file
@@ -532,6 +502,12 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       }
     }
 
+    // when the only language is ISPC we know that the output
+    // type must by a static library
+    if (testLangs.size() == 1 && testLangs.count("ISPC") == 1) {
+      targetType = cmStateEnums::STATIC_LIBRARY;
+    }
+
     std::string const tcConfig =
       this->Makefile->GetSafeDefinition("CMAKE_TRY_COMPILE_CONFIGURATION");
 
@@ -552,19 +528,19 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       return -1;
     }
 
-    const char* def = this->Makefile->GetDefinition("CMAKE_MODULE_PATH");
+    cmProp def = this->Makefile->GetDefinition("CMAKE_MODULE_PATH");
     fprintf(fout, "cmake_minimum_required(VERSION %u.%u.%u.%u)\n",
             cmVersion::GetMajorVersion(), cmVersion::GetMinorVersion(),
             cmVersion::GetPatchVersion(), cmVersion::GetTweakVersion());
     if (def) {
-      fprintf(fout, "set(CMAKE_MODULE_PATH \"%s\")\n", def);
+      fprintf(fout, "set(CMAKE_MODULE_PATH \"%s\")\n", def->c_str());
     }
 
     /* Set MSVC runtime library policy to match our selection.  */
-    if (const char* msvcRuntimeLibraryDefault =
+    if (cmProp msvcRuntimeLibraryDefault =
           this->Makefile->GetDefinition(kCMAKE_MSVC_RUNTIME_LIBRARY_DEFAULT)) {
       fprintf(fout, "cmake_policy(SET CMP0091 %s)\n",
-              *msvcRuntimeLibraryDefault ? "NEW" : "OLD");
+              !msvcRuntimeLibraryDefault->empty() ? "NEW" : "OLD");
     }
 
     /* Set CUDA architectures policy to match outer project.  */
@@ -580,14 +556,14 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       projectLangs += " " + li;
       std::string rulesOverrideBase = "CMAKE_USER_MAKE_RULES_OVERRIDE";
       std::string rulesOverrideLang = cmStrCat(rulesOverrideBase, "_", li);
-      if (const char* rulesOverridePath =
+      if (cmProp rulesOverridePath =
             this->Makefile->GetDefinition(rulesOverrideLang)) {
         fprintf(fout, "set(%s \"%s\")\n", rulesOverrideLang.c_str(),
-                rulesOverridePath);
-      } else if (const char* rulesOverridePath2 =
+                rulesOverridePath->c_str());
+      } else if (cmProp rulesOverridePath2 =
                    this->Makefile->GetDefinition(rulesOverrideBase)) {
         fprintf(fout, "set(%s \"%s\")\n", rulesOverrideBase.c_str(),
-                rulesOverridePath2);
+                rulesOverridePath2->c_str());
       }
     }
     fprintf(fout, "project(CMAKE_TRY_COMPILE%s)\n", projectLangs.c_str());
@@ -602,9 +578,9 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
     fprintf(fout, "set(CMAKE_VERBOSE_MAKEFILE 1)\n");
     for (std::string const& li : testLangs) {
       std::string langFlags = "CMAKE_" + li + "_FLAGS";
-      const char* flags = this->Makefile->GetDefinition(langFlags);
+      cmProp flags = this->Makefile->GetDefinition(langFlags);
       fprintf(fout, "set(CMAKE_%s_FLAGS %s)\n", li.c_str(),
-              cmOutputConverter::EscapeForCMake(flags ? flags : "").c_str());
+              cmOutputConverter::EscapeForCMake(cmToCStrSafe(flags)).c_str());
       fprintf(fout,
               "set(CMAKE_%s_FLAGS \"${CMAKE_%s_FLAGS}"
               " ${COMPILE_DEFINITIONS}\")\n",
@@ -641,10 +617,10 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
         for (std::string const& li : testLangs) {
           std::string const langFlagsCfg =
             cmStrCat("CMAKE_", li, "_FLAGS_", cfg);
-          const char* flagsCfg = this->Makefile->GetDefinition(langFlagsCfg);
-          fprintf(fout, "set(%s %s)\n", langFlagsCfg.c_str(),
-                  cmOutputConverter::EscapeForCMake(flagsCfg ? flagsCfg : "")
-                    .c_str());
+          cmProp flagsCfg = this->Makefile->GetDefinition(langFlagsCfg);
+          fprintf(
+            fout, "set(%s %s)\n", langFlagsCfg.c_str(),
+            cmOutputConverter::EscapeForCMake(cmToCStrSafe(flagsCfg)).c_str());
         }
       } break;
     }
@@ -674,12 +650,11 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       case cmPolicies::NEW:
         // NEW behavior is to pass linker flags.
         {
-          const char* exeLinkFlags =
+          cmProp exeLinkFlags =
             this->Makefile->GetDefinition("CMAKE_EXE_LINKER_FLAGS");
-          fprintf(
-            fout, "set(CMAKE_EXE_LINKER_FLAGS %s)\n",
-            cmOutputConverter::EscapeForCMake(exeLinkFlags ? exeLinkFlags : "")
-              .c_str());
+          fprintf(fout, "set(CMAKE_EXE_LINKER_FLAGS %s)\n",
+                  cmOutputConverter::EscapeForCMake(cmToCStrSafe(exeLinkFlags))
+                    .c_str());
         }
         break;
     }
@@ -721,14 +696,28 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
     // Forward a set of variables to the inner project cache.
     {
       std::set<std::string> vars;
-      vars.insert(kCMAKE_C_COMPILER_EXTERNAL_TOOLCHAIN);
-      vars.insert(kCMAKE_C_COMPILER_TARGET);
-      vars.insert(kCMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN);
-      vars.insert(kCMAKE_CXX_COMPILER_TARGET);
+      vars.insert(&c_properties[lang_property_start],
+                  &c_properties[lang_property_start + lang_property_size]);
+      vars.insert(&cxx_properties[lang_property_start],
+                  &cxx_properties[lang_property_start + lang_property_size]);
+      vars.insert(&cuda_properties[lang_property_start],
+                  &cuda_properties[lang_property_start + lang_property_size]);
+      vars.insert(
+        &fortran_properties[lang_property_start],
+        &fortran_properties[lang_property_start + lang_property_size]);
+      vars.insert(&objc_properties[lang_property_start],
+                  &objc_properties[lang_property_start + lang_property_size]);
+      vars.insert(
+        &objcxx_properties[lang_property_start],
+        &objcxx_properties[lang_property_start + lang_property_size]);
+      vars.insert(&ispc_properties[lang_property_start],
+                  &ispc_properties[lang_property_start + lang_property_size]);
+      vars.insert(&swift_properties[lang_property_start],
+                  &swift_properties[lang_property_start + lang_property_size]);
       vars.insert(kCMAKE_CUDA_ARCHITECTURES);
-      vars.insert(kCMAKE_CUDA_COMPILER_TARGET);
       vars.insert(kCMAKE_CUDA_RUNTIME_LIBRARY);
       vars.insert(kCMAKE_ENABLE_EXPORTS);
+      vars.insert(kCMAKE_ISPC_INSTRUCTION_SETS);
       vars.insert(kCMAKE_LINK_SEARCH_END_STATIC);
       vars.insert(kCMAKE_LINK_SEARCH_START_STATIC);
       vars.insert(kCMAKE_OSX_ARCHITECTURES);
@@ -739,13 +728,12 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       vars.insert(kCMAKE_SYSROOT);
       vars.insert(kCMAKE_SYSROOT_COMPILE);
       vars.insert(kCMAKE_SYSROOT_LINK);
-      vars.insert(kCMAKE_Swift_COMPILER_TARGET);
       vars.insert(kCMAKE_WARN_DEPRECATED);
       vars.emplace("CMAKE_MSVC_RUNTIME_LIBRARY"_s);
 
-      if (const char* varListStr = this->Makefile->GetDefinition(
+      if (cmProp varListStr = this->Makefile->GetDefinition(
             kCMAKE_TRY_COMPILE_PLATFORM_VARIABLES)) {
-        std::vector<std::string> varList = cmExpandedList(varListStr);
+        std::vector<std::string> varList = cmExpandedList(*varListStr);
         vars.insert(varList.begin(), varList.end());
       }
 
@@ -753,10 +741,24 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
           cmPolicies::NEW) {
         // To ensure full support of PIE, propagate cache variables
         // driving the link options
-        vars.insert(kCMAKE_C_LINK_PIE_SUPPORTED);
-        vars.insert(kCMAKE_C_LINK_NO_PIE_SUPPORTED);
-        vars.insert(kCMAKE_CXX_LINK_PIE_SUPPORTED);
-        vars.insert(kCMAKE_CXX_LINK_NO_PIE_SUPPORTED);
+        vars.insert(&c_properties[pie_property_start],
+                    &c_properties[pie_property_start + pie_property_size]);
+        vars.insert(&cxx_properties[pie_property_start],
+                    &cxx_properties[pie_property_start + pie_property_size]);
+        vars.insert(&cuda_properties[pie_property_start],
+                    &cuda_properties[pie_property_start + pie_property_size]);
+        vars.insert(
+          &fortran_properties[pie_property_start],
+          &fortran_properties[pie_property_start + pie_property_size]);
+        vars.insert(&objc_properties[pie_property_start],
+                    &objc_properties[pie_property_start + pie_property_size]);
+        vars.insert(
+          &objcxx_properties[pie_property_start],
+          &objcxx_properties[pie_property_start + pie_property_size]);
+        vars.insert(&ispc_properties[pie_property_start],
+                    &ispc_properties[pie_property_start + pie_property_size]);
+        vars.insert(&swift_properties[pie_property_start],
+                    &swift_properties[pie_property_start + pie_property_size]);
       }
 
       /* for the TRY_COMPILEs we want to be able to specify the architecture.
@@ -766,16 +768,16 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
          cmLocalGenerator doesn't allow building for "the other"
          architecture only via CMAKE_OSX_ARCHITECTURES.
          */
-      if (const char* tcArchs = this->Makefile->GetDefinition(
+      if (cmProp tcArchs = this->Makefile->GetDefinition(
             kCMAKE_TRY_COMPILE_OSX_ARCHITECTURES)) {
         vars.erase(kCMAKE_OSX_ARCHITECTURES);
-        std::string flag = "-DCMAKE_OSX_ARCHITECTURES=" + std::string(tcArchs);
+        std::string flag = "-DCMAKE_OSX_ARCHITECTURES=" + *tcArchs;
         cmakeFlags.push_back(std::move(flag));
       }
 
       for (std::string const& var : vars) {
-        if (const char* val = this->Makefile->GetDefinition(var)) {
-          std::string flag = "-D" + var + "=" + val;
+        if (cmProp val = this->Makefile->GetDefinition(var)) {
+          std::string flag = "-D" + var + "=" + *val;
           cmakeFlags.push_back(std::move(flag));
         }
       }
@@ -819,21 +821,17 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
     }
     fprintf(fout, ")\n");
 
-    bool const testC = testLangs.find("C") != testLangs.end();
-    bool const testObjC = testLangs.find("OBJC") != testLangs.end();
-    bool const testCxx = testLangs.find("CXX") != testLangs.end();
-    bool const testObjCxx = testLangs.find("OBJCXX") != testLangs.end();
-    bool const testCuda = testLangs.find("CUDA") != testLangs.end();
+    cState.Enabled(testLangs.find("C") != testLangs.end());
+    cxxState.Enabled(testLangs.find("CXX") != testLangs.end());
+    cudaState.Enabled(testLangs.find("CUDA") != testLangs.end());
+    objcState.Enabled(testLangs.find("OBJC") != testLangs.end());
+    objcxxState.Enabled(testLangs.find("OBJCXX") != testLangs.end());
 
     bool warnCMP0067 = false;
     bool honorStandard = true;
 
-    if (!didCStandard && !didCxxStandard && !didObjCStandard &&
-        !didObjCxxStandard && !didCudaStandard && !didCStandardRequired &&
-        !didCxxStandardRequired && !didObjCStandardRequired &&
-        !didObjCxxStandardRequired && !didCudaStandardRequired &&
-        !didCExtensions && !didCxxExtensions && !didObjCExtensions &&
-        !didObjCxxExtensions && !didCudaExtensions) {
+    if (cState.DidNone() && cxxState.DidNone() && objcState.DidNone() &&
+        objcxxState.DidNone() && cudaState.DidNone()) {
       switch (this->Makefile->GetPolicyStatus(cmPolicies::CMP0067)) {
         case cmPolicies::WARN:
           warnCMP0067 = this->Makefile->PolicyOptionalWarningEnabled(
@@ -855,46 +853,20 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       }
     }
 
-    if (honorStandard || warnCMP0067) {
+    std::vector<std::string> warnCMP0067Variables;
 
-      auto testLanguage =
-        [&](bool testLang, bool didLangStandard, bool didLangStandardRequired,
-            bool didLangExtensions, std::string& langStandard,
-            std::string& langStandardRequired, std::string& langExtensions,
-            const std::string& lang) {
-          if (testLang) {
-            if (!didLangStandard) {
-              langStandard = this->LookupStdVar(
-                cmStrCat("CMAKE_", lang, "_STANDARD"), warnCMP0067);
-            }
-            if (!didLangStandardRequired) {
-              langStandardRequired = this->LookupStdVar(
-                cmStrCat("CMAKE_", lang, "_STANDARD_REQUIRED"), warnCMP0067);
-            }
-            if (!didLangExtensions) {
-              langExtensions = this->LookupStdVar(
-                cmStrCat("CMAKE_", lang, "_EXTENSIONS"), warnCMP0067);
-            }
-          }
-        };
-
-      testLanguage(testC, didCStandard, didCStandardRequired, didCExtensions,
-                   cStandard, cStandardRequired, cExtensions, "C");
-      testLanguage(testObjC, didObjCStandard, didObjCStandardRequired,
-                   didObjCExtensions, objcStandard, objcStandardRequired,
-                   objcExtensions, "OBJC");
-      testLanguage(testCxx, didCxxStandard, didCxxStandardRequired,
-                   didCxxExtensions, cxxStandard, cxxStandardRequired,
-                   cxxExtensions, "CXX");
-      testLanguage(testObjCxx, didObjCxxStandard, didObjCxxStandardRequired,
-                   didObjCxxExtensions, objcxxStandard, objcxxStandardRequired,
-                   objcxxExtensions, "OBJCXX");
-      testLanguage(testCuda, didCudaStandard, didCudaStandardRequired,
-                   didCudaExtensions, cudaStandard, cudaStandardRequired,
-                   cudaExtensions, "CUDA");
-    }
+    cState.LoadUnsetPropertyValues(this->Makefile, honorStandard, warnCMP0067,
+                                   warnCMP0067Variables);
+    cxxState.LoadUnsetPropertyValues(this->Makefile, honorStandard,
+                                     warnCMP0067, warnCMP0067Variables);
+    cudaState.LoadUnsetPropertyValues(this->Makefile, honorStandard,
+                                      warnCMP0067, warnCMP0067Variables);
+    objcState.LoadUnsetPropertyValues(this->Makefile, honorStandard,
+                                      warnCMP0067, warnCMP0067Variables);
+    objcxxState.LoadUnsetPropertyValues(this->Makefile, honorStandard,
+                                        warnCMP0067, warnCMP0067Variables);
 
-    if (!this->WarnCMP0067.empty()) {
+    if (!warnCMP0067Variables.empty()) {
       std::ostringstream w;
       /* clang-format off */
       w << cmPolicies::GetPolicyWarning(cmPolicies::CMP0067) << "\n"
@@ -902,43 +874,17 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
         "is not honoring language standard variables in the test project:\n"
         ;
       /* clang-format on */
-      for (std::string const& vi : this->WarnCMP0067) {
+      for (std::string const& vi : warnCMP0067Variables) {
         w << "  " << vi << "\n";
       }
       this->Makefile->IssueMessage(MessageType::AUTHOR_WARNING, w.str());
     }
 
-    auto writeLanguageProperties = [&](bool testLang,
-                                       const std::string& langStandard,
-                                       const std::string& langStandardRequired,
-                                       const std::string& langExtensions,
-                                       const std::string& lang) {
-      if (testLang) {
-        if (!langStandard.empty()) {
-          writeProperty(fout, targetName, cmStrCat(lang, "_STANDARD"),
-                        langStandard);
-        }
-        if (!langStandardRequired.empty()) {
-          writeProperty(fout, targetName, cmStrCat(lang, "_STANDARD_REQUIRED"),
-                        langStandardRequired);
-        }
-        if (!langExtensions.empty()) {
-          writeProperty(fout, targetName, cmStrCat(lang, "_EXTENSIONS"),
-                        langExtensions);
-        }
-      }
-    };
-
-    writeLanguageProperties(testC, cStandard, cStandardRequired, cExtensions,
-                            "C");
-    writeLanguageProperties(testObjC, objcStandard, objcStandardRequired,
-                            objcExtensions, "OBJC");
-    writeLanguageProperties(testCxx, cxxStandard, cxxStandardRequired,
-                            cxxExtensions, "CXX");
-    writeLanguageProperties(testObjCxx, objcxxStandard, objcxxStandardRequired,
-                            objcxxExtensions, "OBJCXX");
-    writeLanguageProperties(testCuda, cudaStandard, cudaStandardRequired,
-                            cudaExtensions, "CUDA");
+    cState.WriteProperties(fout, targetName);
+    cxxState.WriteProperties(fout, targetName);
+    cudaState.WriteProperties(fout, targetName);
+    objcState.WriteProperties(fout, targetName);
+    objcxxState.WriteProperties(fout, targetName);
 
     if (!linkOptions.empty()) {
       std::vector<std::string> options;
@@ -971,8 +917,8 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
   if (this->Makefile->GetState()->UseGhsMultiIDE()) {
     // Forward the GHS variables to the inner project cache.
     for (std::string const& var : ghs_platform_vars) {
-      if (const char* val = this->Makefile->GetDefinition(var)) {
-        std::string flag = "-D" + var + "=" + "'" + val + "'";
+      if (cmProp val = this->Makefile->GetDefinition(var)) {
+        std::string flag = "-D" + var + "=" + "'" + *val + "'";
         cmakeFlags.push_back(std::move(flag));
       }
     }
@@ -1109,18 +1055,18 @@ void cmCoreTryCompile::FindOutputFile(const std::string& targetName,
   std::vector<std::string> searchDirs;
   searchDirs.emplace_back();
 
-  const char* config =
+  cmProp config =
     this->Makefile->GetDefinition("CMAKE_TRY_COMPILE_CONFIGURATION");
   // if a config was specified try that first
-  if (config && config[0]) {
-    std::string tmp = cmStrCat('/', config);
+  if (cmNonempty(config)) {
+    std::string tmp = cmStrCat('/', *config);
     searchDirs.push_back(std::move(tmp));
   }
   searchDirs.emplace_back("/Debug");
 #if defined(__APPLE__)
   std::string app = "/" + targetName + ".app";
-  if (config && config[0]) {
-    std::string tmp = cmStrCat('/', config, app);
+  if (cmNonempty(config)) {
+    std::string tmp = cmStrCat('/', *config, app);
     searchDirs.push_back(std::move(tmp));
   }
   std::string tmp = "/Debug" + app;
diff --git a/Source/cmCoreTryCompile.h b/Source/cmCoreTryCompile.h
index ae714a6..594fd7f 100644
--- a/Source/cmCoreTryCompile.h
+++ b/Source/cmCoreTryCompile.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCoreTryCompile_h
-#define cmCoreTryCompile_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -47,10 +46,4 @@ protected:
   std::string OutputFile;
   std::string FindErrorMessage;
   bool SrcFileSignature = false;
-
-private:
-  std::vector<std::string> WarnCMP0067;
-  std::string LookupStdVar(std::string const& var, bool warnCMP0067);
 };
-
-#endif
diff --git a/Source/cmCreateTestSourceList.cxx b/Source/cmCreateTestSourceList.cxx
index 9d492ba..9c4deea 100644
--- a/Source/cmCreateTestSourceList.cxx
+++ b/Source/cmCreateTestSourceList.cxx
@@ -127,7 +127,7 @@ bool cmCreateTestSourceList(std::vector<std::string> const& args,
   mf.AddDefinition("CMAKE_FORWARD_DECLARE_TESTS", forwardDeclareCode);
   mf.AddDefinition("CMAKE_FUNCTION_TABLE_ENTIRES", functionMapCode);
   bool res = true;
-  if (!mf.ConfigureFile(configFile, driver, false, true, false)) {
+  if (!mf.ConfigureFile(configFile, driver, false, true, false, true)) {
     res = false;
   }
 
diff --git a/Source/cmCreateTestSourceList.h b/Source/cmCreateTestSourceList.h
index 19503f4..a7f11a6 100644
--- a/Source/cmCreateTestSourceList.h
+++ b/Source/cmCreateTestSourceList.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCreateTestSourceList_h
-#define cmCreateTestSourceList_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmCreateTestSourceList(std::vector<std::string> const& args,
                             cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmCryptoHash.h b/Source/cmCryptoHash.h
index f27bb5d..a2d45e7 100644
--- a/Source/cmCryptoHash.h
+++ b/Source/cmCryptoHash.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCryptoHash_h
-#define cmCryptoHash_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -85,5 +84,3 @@ private:
   unsigned int Id;
   struct rhash_context* CTX;
 };
-
-#endif
diff --git a/Source/cmCurl.h b/Source/cmCurl.h
index 7bd036e..fb716f8 100644
--- a/Source/cmCurl.h
+++ b/Source/cmCurl.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCurl_h
-#define cmCurl_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@
 std::string cmCurlSetCAInfo(::CURL* curl, const char* cafile = nullptr);
 std::string cmCurlSetNETRCOption(::CURL* curl, const std::string& netrc_level,
                                  const std::string& netrc_file);
-
-#endif
diff --git a/Source/cmCustomCommand.h b/Source/cmCustomCommand.h
index aa572ad..2036e90 100644
--- a/Source/cmCustomCommand.h
+++ b/Source/cmCustomCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCustomCommand_h
-#define cmCustomCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -114,5 +113,3 @@ private:
   bool CommandExpandLists = false;
   bool StdPipesUTF8 = false;
 };
-
-#endif
diff --git a/Source/cmCustomCommandGenerator.h b/Source/cmCustomCommandGenerator.h
index 67ee9e0..412eba8 100644
--- a/Source/cmCustomCommandGenerator.h
+++ b/Source/cmCustomCommandGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCustomCommandGenerator_h
-#define cmCustomCommandGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -47,5 +46,3 @@ public:
   std::vector<std::string> const& GetDepends() const;
   bool HasOnlyEmptyCommandLines() const;
 };
-
-#endif
diff --git a/Source/cmCustomCommandLines.h b/Source/cmCustomCommandLines.h
index ead5792..ee8d080 100644
--- a/Source/cmCustomCommandLines.h
+++ b/Source/cmCustomCommandLines.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCustomCommandLines_h
-#define cmCustomCommandLines_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -28,5 +27,3 @@ cmCustomCommandLine cmMakeCommandLine(
 /** Return a command line vector with a single command line.  */
 cmCustomCommandLines cmMakeSingleCommandLine(
   std::initializer_list<cm::string_view> ilist);
-
-#endif
diff --git a/Source/cmCustomCommandTypes.h b/Source/cmCustomCommandTypes.h
index d4bf1f9..5c900ce 100644
--- a/Source/cmCustomCommandTypes.h
+++ b/Source/cmCustomCommandTypes.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmCustomCommandTypes_h
-#define cmCustomCommandTypes_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -35,5 +34,3 @@ struct cmUtilityOutput
   std::string Name;
   std::string NameCMP0049;
 };
-
-#endif
diff --git a/Source/cmDefinePropertyCommand.h b/Source/cmDefinePropertyCommand.h
index 60dd76a..3c478b3 100644
--- a/Source/cmDefinePropertyCommand.h
+++ b/Source/cmDefinePropertyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDefinesPropertyCommand_h
-#define cmDefinesPropertyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmDefinePropertyCommand(std::vector<std::string> const& args,
                              cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmDefinitions.cxx b/Source/cmDefinitions.cxx
index 69a6427..4a4f87d 100644
--- a/Source/cmDefinitions.cxx
+++ b/Source/cmDefinitions.cxx
@@ -19,7 +19,6 @@ cmDefinitions::Def const& cmDefinitions::GetInternal(const std::string& key,
   {
     auto it = begin->Map.find(cm::String::borrow(key));
     if (it != begin->Map.end()) {
-      it->second.Used = true;
       return it->second;
     }
   }
@@ -108,16 +107,3 @@ void cmDefinitions::Unset(const std::string& key)
 {
   this->Map[key] = Def();
 }
-
-std::vector<std::string> cmDefinitions::UnusedKeys() const
-{
-  std::vector<std::string> keys;
-  keys.reserve(this->Map.size());
-  // Consider local definitions.
-  for (auto const& mi : this->Map) {
-    if (!mi.second.Used) {
-      keys.push_back(*mi.first.str_if_stable());
-    }
-  }
-  return keys;
-}
diff --git a/Source/cmDefinitions.h b/Source/cmDefinitions.h
index 0e38fb1..b650aa8 100644
--- a/Source/cmDefinitions.h
+++ b/Source/cmDefinitions.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDefinitions_h
-#define cmDefinitions_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -48,9 +47,6 @@ public:
   /** Unset a definition.  */
   void Unset(const std::string& key);
 
-  /** List of unused keys.  */
-  std::vector<std::string> UnusedKeys() const;
-
 private:
   /** String with existence boolean.  */
   struct Def
@@ -62,7 +58,6 @@ private:
     {
     }
     cm::String Value;
-    bool Used = false;
   };
   static Def NoDef;
 
@@ -71,5 +66,3 @@ private:
   static Def const& GetInternal(const std::string& key, StackIter begin,
                                 StackIter end, bool raise);
 };
-
-#endif
diff --git a/Source/cmDepends.cxx b/Source/cmDepends.cxx
index d8aa730..d092f4f 100644
--- a/Source/cmDepends.cxx
+++ b/Source/cmDepends.cxx
@@ -11,6 +11,7 @@
 #include "cmGeneratedFileStream.h"
 #include "cmLocalUnixMakefileGenerator3.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 
@@ -228,19 +229,19 @@ bool cmDepends::CheckDependencies(std::istream& internalDepends,
 void cmDepends::SetIncludePathFromLanguage(const std::string& lang)
 {
   // Look for the new per "TARGET_" variant first:
-  const char* includePath = nullptr;
+  cmProp includePath = nullptr;
   std::string includePathVar =
     cmStrCat("CMAKE_", lang, "_TARGET_INCLUDE_PATH");
   cmMakefile* mf = this->LocalGenerator->GetMakefile();
   includePath = mf->GetDefinition(includePathVar);
   if (includePath) {
-    cmExpandList(includePath, this->IncludePath);
+    cmExpandList(*includePath, this->IncludePath);
   } else {
     // Fallback to the old directory level variable if no per-target var:
     includePathVar = cmStrCat("CMAKE_", lang, "_INCLUDE_PATH");
     includePath = mf->GetDefinition(includePathVar);
     if (includePath) {
-      cmExpandList(includePath, this->IncludePath);
+      cmExpandList(*includePath, this->IncludePath);
     }
   }
 }
diff --git a/Source/cmDepends.h b/Source/cmDepends.h
index 8cf528f..0240da9 100644
--- a/Source/cmDepends.h
+++ b/Source/cmDepends.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDepends_h
-#define cmDepends_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -112,5 +111,3 @@ protected:
 
   void SetIncludePathFromLanguage(const std::string& lang);
 };
-
-#endif
diff --git a/Source/cmDependsC.cxx b/Source/cmDependsC.cxx
index e05c964..e6aef92 100644
--- a/Source/cmDependsC.cxx
+++ b/Source/cmDependsC.cxx
@@ -9,6 +9,7 @@
 #include "cmFileTime.h"
 #include "cmLocalUnixMakefileGenerator3.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 
@@ -38,13 +39,13 @@ cmDependsC::cmDependsC(cmLocalUnixMakefileGenerator3* lg,
   std::string complainRegex = "^$";
   {
     std::string scanRegexVar = cmStrCat("CMAKE_", lang, "_INCLUDE_REGEX_SCAN");
-    if (const char* sr = mf->GetDefinition(scanRegexVar)) {
-      scanRegex = sr;
+    if (cmProp sr = mf->GetDefinition(scanRegexVar)) {
+      scanRegex = *sr;
     }
     std::string complainRegexVar =
       cmStrCat("CMAKE_", lang, "_INCLUDE_REGEX_COMPLAIN");
-    if (const char* cr = mf->GetDefinition(complainRegexVar)) {
-      complainRegex = cr;
+    if (cmProp cr = mf->GetDefinition(complainRegexVar)) {
+      complainRegex = *cr;
     }
   }
 
diff --git a/Source/cmDependsC.h b/Source/cmDependsC.h
index e01faa4..c79da1a 100644
--- a/Source/cmDependsC.h
+++ b/Source/cmDependsC.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDependsC_h
-#define cmDependsC_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -93,5 +92,3 @@ protected:
   void WriteCacheFile() const;
   void ReadCacheFile();
 };
-
-#endif
diff --git a/Source/cmDependsFortran.cxx b/Source/cmDependsFortran.cxx
index 8f02d95..a239418 100644
--- a/Source/cmDependsFortran.cxx
+++ b/Source/cmDependsFortran.cxx
@@ -15,6 +15,7 @@
 #include "cmLocalUnixMakefileGenerator3.h"
 #include "cmMakefile.h"
 #include "cmOutputConverter.h"
+#include "cmProperty.h"
 #include "cmStateDirectory.h"
 #include "cmStateSnapshot.h"
 #include "cmStringAlgorithms.h"
@@ -394,9 +395,9 @@ bool cmDependsFortran::WriteDependenciesReal(std::string const& obj,
       makeDepends << "\t$(CMAKE_COMMAND) -E cmake_copy_f90_mod " << modFile
                   << ' ' << stampFileForShell;
       cmMakefile* mf = this->LocalGenerator->GetMakefile();
-      const char* cid = mf->GetDefinition("CMAKE_Fortran_COMPILER_ID");
-      if (cid && *cid) {
-        makeDepends << ' ' << cid;
+      cmProp cid = mf->GetDefinition("CMAKE_Fortran_COMPILER_ID");
+      if (cmNonempty(cid)) {
+        makeDepends << ' ' << *cid;
       }
       makeDepends << '\n';
     }
diff --git a/Source/cmDependsFortran.h b/Source/cmDependsFortran.h
index 3e306dd..e377a2c 100644
--- a/Source/cmDependsFortran.h
+++ b/Source/cmDependsFortran.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFortran_h
-#define cmFortran_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -91,5 +90,3 @@ private:
   std::string MaybeConvertToRelativePath(std::string const& base,
                                          std::string const& path);
 };
-
-#endif
diff --git a/Source/cmDependsJava.h b/Source/cmDependsJava.h
index 2a90251..1db7ce1 100644
--- a/Source/cmDependsJava.h
+++ b/Source/cmDependsJava.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDependsJava_h
-#define cmDependsJava_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -36,5 +35,3 @@ protected:
                          const std::string& internalDependsFileName,
                          DependencyMap& validDeps) override;
 };
-
-#endif
diff --git a/Source/cmDependsJavaParserHelper.h b/Source/cmDependsJavaParserHelper.h
index c545ee2..869b7d4 100644
--- a/Source/cmDependsJavaParserHelper.h
+++ b/Source/cmDependsJavaParserHelper.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDependsJavaParserHelper_h
-#define cmDependsJavaParserHelper_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -97,5 +96,3 @@ private:
 #define YYSTYPE_IS_DECLARED
 #define YY_EXTRA_TYPE cmDependsJavaParserHelper*
 #define YY_DECL int cmDependsJava_yylex(YYSTYPE* yylvalp, yyscan_t yyscanner)
-
-#endif
diff --git a/Source/cmDocumentation.h b/Source/cmDocumentation.h
index 3768e1a..313be32 100644
--- a/Source/cmDocumentation.h
+++ b/Source/cmDocumentation.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef _cmDocumentation_h
-#define _cmDocumentation_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -125,5 +124,3 @@ private:
 
   static void WarnFormFromFilename(RequestedHelpItem& request, bool& result);
 };
-
-#endif
diff --git a/Source/cmDocumentationEntry.h b/Source/cmDocumentationEntry.h
index afbca5e..89a2899 100644
--- a/Source/cmDocumentationEntry.h
+++ b/Source/cmDocumentationEntry.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmDocumentationEntry_h
-#define cmDocumentationEntry_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -33,5 +32,3 @@ struct cmDocumentationEntry
     }
   }
 };
-
-#endif
diff --git a/Source/cmDocumentationFormatter.h b/Source/cmDocumentationFormatter.h
index 17b63da..cb3038a 100644
--- a/Source/cmDocumentationFormatter.h
+++ b/Source/cmDocumentationFormatter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef _cmDocumentationFormatter_h
-#define _cmDocumentationFormatter_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -62,5 +61,3 @@ private:
   int TextWidth = 77;
   const char* TextIndent = "";
 };
-
-#endif
diff --git a/Source/cmDocumentationSection.h b/Source/cmDocumentationSection.h
index 641263d..276e520 100644
--- a/Source/cmDocumentationSection.h
+++ b/Source/cmDocumentationSection.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef _cmDocumentationSection_h
-#define _cmDocumentationSection_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -67,5 +66,3 @@ private:
   std::string Name;
   std::vector<cmDocumentationEntry> Entries;
 };
-
-#endif
diff --git a/Source/cmDynamicLoader.h b/Source/cmDynamicLoader.h
index 4b89388..53ea5cb 100644
--- a/Source/cmDynamicLoader.h
+++ b/Source/cmDynamicLoader.h
@@ -5,8 +5,7 @@
 // cmDynamicLoader provides a portable interface to loading dynamic
 // libraries into a process.
 
-#ifndef cmDynamicLoader_h
-#define cmDynamicLoader_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -29,5 +28,3 @@ protected:
   cmDynamicLoader() = default;
   ~cmDynamicLoader() = default;
 };
-
-#endif
diff --git a/Source/cmELF.h b/Source/cmELF.h
index 123bf9b..99eb4f4 100644
--- a/Source/cmELF.h
+++ b/Source/cmELF.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmELF_h
-#define cmELF_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -112,5 +111,3 @@ private:
   std::unique_ptr<cmELFInternal> Internal;
   std::string ErrorMessage;
 };
-
-#endif
diff --git a/Source/cmEnableLanguageCommand.h b/Source/cmEnableLanguageCommand.h
index 1f8c4ce..730ba65 100644
--- a/Source/cmEnableLanguageCommand.h
+++ b/Source/cmEnableLanguageCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmEnableLanguageCommand_h
-#define cmEnableLanguageCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmEnableLanguageCommand(std::vector<std::string> const& args,
                              cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmEnableTestingCommand.h b/Source/cmEnableTestingCommand.h
index e4593f2..1722511 100644
--- a/Source/cmEnableTestingCommand.h
+++ b/Source/cmEnableTestingCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmEnableTestingCommand_h
-#define cmEnableTestingCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -25,5 +24,3 @@ class cmExecutionStatus;
  */
 bool cmEnableTestingCommand(std::vector<std::string> const&,
                             cmExecutionStatus&);
-
-#endif
diff --git a/Source/cmExecProgramCommand.h b/Source/cmExecProgramCommand.h
index 7c751e1..111a56e 100644
--- a/Source/cmExecProgramCommand.h
+++ b/Source/cmExecProgramCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExecProgramCommand_h
-#define cmExecProgramCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -19,5 +18,3 @@ class cmExecutionStatus;
  */
 bool cmExecProgramCommand(std::vector<std::string> const& args,
                           cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmExecuteProcessCommand.h b/Source/cmExecuteProcessCommand.h
index 9c4b600..cc8cc38 100644
--- a/Source/cmExecuteProcessCommand.h
+++ b/Source/cmExecuteProcessCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExecuteProcessCommand_h
-#define cmExecuteProcessCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -18,5 +17,3 @@ class cmExecutionStatus;
  */
 bool cmExecuteProcessCommand(std::vector<std::string> const& args,
                              cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmExecutionStatus.h b/Source/cmExecutionStatus.h
index d2cc9b8..0feaedf 100644
--- a/Source/cmExecutionStatus.h
+++ b/Source/cmExecutionStatus.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExecutionStatus_h
-#define cmExecutionStatus_h
+#pragma once
 
 #include <cmConfigure.h> // IWYU pragma: keep
 
@@ -48,5 +47,3 @@ private:
   bool ContinueInvoked = false;
   bool NestedError = false;
 };
-
-#endif
diff --git a/Source/cmExpandedCommandArgument.cxx b/Source/cmExpandedCommandArgument.cxx
index 43f648b..1f14fc4 100644
--- a/Source/cmExpandedCommandArgument.cxx
+++ b/Source/cmExpandedCommandArgument.cxx
@@ -37,8 +37,3 @@ bool cmExpandedCommandArgument::empty() const
 {
   return this->Value.empty();
 }
-
-const char* cmExpandedCommandArgument::c_str() const
-{
-  return this->Value.c_str();
-}
diff --git a/Source/cmExpandedCommandArgument.h b/Source/cmExpandedCommandArgument.h
index 69d35de..1ff6ed1 100644
--- a/Source/cmExpandedCommandArgument.h
+++ b/Source/cmExpandedCommandArgument.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExpandedCommandArgument_h
-#define cmExpandedCommandArgument_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -29,11 +28,7 @@ public:
 
   bool empty() const;
 
-  const char* c_str() const;
-
 private:
   std::string Value;
   bool Quoted = false;
 };
-
-#endif
diff --git a/Source/cmExportBuildAndroidMKGenerator.h b/Source/cmExportBuildAndroidMKGenerator.h
index a9b6107..250564f 100644
--- a/Source/cmExportBuildAndroidMKGenerator.h
+++ b/Source/cmExportBuildAndroidMKGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportBuildAndroidMKGenerator_h
-#define cmExportBuildAndroidMKGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -63,5 +62,3 @@ protected:
     cmGeneratorTarget const* target, std::ostream& os,
     const ImportPropertyMap& properties) override;
 };
-
-#endif
diff --git a/Source/cmExportBuildFileGenerator.h b/Source/cmExportBuildFileGenerator.h
index 66e8cbb..264494d 100644
--- a/Source/cmExportBuildFileGenerator.h
+++ b/Source/cmExportBuildFileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportBuildFileGenerator_h
-#define cmExportBuildFileGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -85,5 +84,3 @@ protected:
   std::vector<cmGeneratorTarget*> Exports;
   cmLocalGenerator* LG;
 };
-
-#endif
diff --git a/Source/cmExportCommand.cxx b/Source/cmExportCommand.cxx
index 9f8a821..352eaf2 100644
--- a/Source/cmExportCommand.cxx
+++ b/Source/cmExportCommand.cxx
@@ -223,11 +223,9 @@ bool cmExportCommand(std::vector<std::string> const& args,
   ebfg->SetExportOld(arguments.ExportOld);
 
   // Compute the set of configurations exported.
-  std::vector<std::string> configurationTypes;
-  mf.GetConfigurations(configurationTypes);
-  if (configurationTypes.empty()) {
-    configurationTypes.emplace_back();
-  }
+  std::vector<std::string> configurationTypes =
+    mf.GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
+
   for (std::string const& ct : configurationTypes) {
     ebfg->AddConfiguration(ct);
   }
diff --git a/Source/cmExportCommand.h b/Source/cmExportCommand.h
index 9655628..3f87bcf 100644
--- a/Source/cmExportCommand.h
+++ b/Source/cmExportCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportCommand_h
-#define cmExportCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmExportCommand(std::vector<std::string> const& args,
                      cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmExportFileGenerator.cxx b/Source/cmExportFileGenerator.cxx
index 4d0e099..58aa391 100644
--- a/Source/cmExportFileGenerator.cxx
+++ b/Source/cmExportFileGenerator.cxx
@@ -567,8 +567,9 @@ void cmExportFileGenerator::PopulateCompatibleInterfaceProperties(
   if (gtarget->GetType() != cmStateEnums::INTERFACE_LIBRARY) {
     getCompatibleInterfaceProperties(gtarget, ifaceProperties, "");
 
-    std::vector<std::string> configNames;
-    gtarget->Target->GetMakefile()->GetConfigurations(configNames);
+    std::vector<std::string> configNames =
+      gtarget->Target->GetMakefile()->GetGeneratorConfigs(
+        cmMakefile::ExcludeEmptyConfig);
 
     for (std::string const& cn : configNames) {
       getCompatibleInterfaceProperties(gtarget, ifaceProperties, cn);
diff --git a/Source/cmExportFileGenerator.h b/Source/cmExportFileGenerator.h
index e9d0da7..45eaed0 100644
--- a/Source/cmExportFileGenerator.h
+++ b/Source/cmExportFileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportFileGenerator_h
-#define cmExportFileGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -223,5 +222,3 @@ private:
   virtual std::string InstallNameDir(cmGeneratorTarget* target,
                                      const std::string& config) = 0;
 };
-
-#endif
diff --git a/Source/cmExportInstallAndroidMKGenerator.h b/Source/cmExportInstallAndroidMKGenerator.h
index 8883ffa..40978e0 100644
--- a/Source/cmExportInstallAndroidMKGenerator.h
+++ b/Source/cmExportInstallAndroidMKGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportInstallAndroidMKGenerator_h
-#define cmExportInstallAndroidMKGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -69,5 +68,3 @@ protected:
   bool GenerateImportFileConfig(const std::string& config,
                                 std::vector<std::string>&) override;
 };
-
-#endif
diff --git a/Source/cmExportInstallFileGenerator.h b/Source/cmExportInstallFileGenerator.h
index 5fa812c..2d8de9d 100644
--- a/Source/cmExportInstallFileGenerator.h
+++ b/Source/cmExportInstallFileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportInstallFileGenerator_h
-#define cmExportInstallFileGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -103,5 +102,3 @@ protected:
   // The import file generated for each configuration.
   std::map<std::string, std::string> ConfigImportFiles;
 };
-
-#endif
diff --git a/Source/cmExportLibraryDependenciesCommand.h b/Source/cmExportLibraryDependenciesCommand.h
index 230c906..1834bfa 100644
--- a/Source/cmExportLibraryDependenciesCommand.h
+++ b/Source/cmExportLibraryDependenciesCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportLibraryDependenciesCommand_h
-#define cmExportLibraryDependenciesCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmExportLibraryDependenciesCommand(std::vector<std::string> const& args,
                                         cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmExportSet.h b/Source/cmExportSet.h
index f0d921f..07deb11 100644
--- a/Source/cmExportSet.h
+++ b/Source/cmExportSet.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportSet_h
-#define cmExportSet_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -61,5 +60,3 @@ public:
    */
   cmExportSet& operator[](const std::string& name);
 };
-
-#endif
diff --git a/Source/cmExportTryCompileFileGenerator.h b/Source/cmExportTryCompileFileGenerator.h
index 7573427..6bf5781 100644
--- a/Source/cmExportTryCompileFileGenerator.h
+++ b/Source/cmExportTryCompileFileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExportTryCompileFileGenerator_h
-#define cmExportTryCompileFileGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -58,5 +57,3 @@ private:
   std::string Config;
   std::vector<std::string> Languages;
 };
-
-#endif
diff --git a/Source/cmExprParserHelper.h b/Source/cmExprParserHelper.h
index 717acdc..54dd6a4 100644
--- a/Source/cmExprParserHelper.h
+++ b/Source/cmExprParserHelper.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExprParserHelper_h
-#define cmExprParserHelper_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -58,5 +57,3 @@ private:
 #define YYSTYPE_IS_DECLARED
 #define YY_EXTRA_TYPE cmExprParserHelper*
 #define YY_DECL int cmExpr_yylex(YYSTYPE* yylvalp, yyscan_t yyscanner)
-
-#endif
diff --git a/Source/cmExternalMakefileProjectGenerator.h b/Source/cmExternalMakefileProjectGenerator.h
index 2b8d505..3ade67b 100644
--- a/Source/cmExternalMakefileProjectGenerator.h
+++ b/Source/cmExternalMakefileProjectGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExternalMakefileProjectGenerator_h
-#define cmExternalMakefileProjectGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -109,5 +108,3 @@ public:
     return p;
   }
 };
-
-#endif
diff --git a/Source/cmExtraCodeBlocksGenerator.cxx b/Source/cmExtraCodeBlocksGenerator.cxx
index 32b0ca9..87b8f9b 100644
--- a/Source/cmExtraCodeBlocksGenerator.cxx
+++ b/Source/cmExtraCodeBlocksGenerator.cxx
@@ -16,6 +16,7 @@
 #include "cmGlobalGenerator.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmSourceFile.h"
 #include "cmStateTypes.h"
@@ -95,7 +96,7 @@ struct Tree
   std::string path; // only one component of the path
   std::vector<Tree> folders;
   std::set<std::string> files;
-  void InsertPath(const std::vector<std::string>& splitted,
+  void InsertPath(const std::vector<std::string>& split,
                   std::vector<std::string>::size_type start,
                   const std::string& fileName);
   void BuildVirtualFolder(cmXMLWriter& xml) const;
@@ -106,34 +107,34 @@ struct Tree
                      const std::string& fsPath) const;
 };
 
-void Tree::InsertPath(const std::vector<std::string>& splitted,
+void Tree::InsertPath(const std::vector<std::string>& split,
                       std::vector<std::string>::size_type start,
                       const std::string& fileName)
 {
-  if (start == splitted.size()) {
+  if (start == split.size()) {
     files.insert(fileName);
     return;
   }
   for (Tree& folder : folders) {
-    if (folder.path == splitted[start]) {
-      if (start + 1 < splitted.size()) {
-        folder.InsertPath(splitted, start + 1, fileName);
+    if (folder.path == split[start]) {
+      if (start + 1 < split.size()) {
+        folder.InsertPath(split, start + 1, fileName);
         return;
       }
-      // last part of splitted
+      // last part of split
       folder.files.insert(fileName);
       return;
     }
   }
   // Not found in folders, thus insert
   Tree newFolder;
-  newFolder.path = splitted[start];
-  if (start + 1 < splitted.size()) {
-    newFolder.InsertPath(splitted, start + 1, fileName);
+  newFolder.path = split[start];
+  if (start + 1 < split.size()) {
+    newFolder.InsertPath(split, start + 1, fileName);
     folders.push_back(newFolder);
     return;
   }
-  // last part of splitted
+  // last part of split
   newFolder.files.insert(fileName);
   folders.push_back(newFolder);
 }
@@ -224,11 +225,11 @@ void cmExtraCodeBlocksGenerator::CreateNewProjectFile(
 
       const std::string& relative = cmSystemTools::RelativePath(
         it.second[0]->GetSourceDirectory(), listFile);
-      std::vector<std::string> splitted;
-      cmSystemTools::SplitPath(relative, splitted, false);
+      std::vector<std::string> split;
+      cmSystemTools::SplitPath(relative, split, false);
       // Split filename from path
-      std::string fileName = *(splitted.end() - 1);
-      splitted.erase(splitted.end() - 1, splitted.end());
+      std::string fileName = *(split.end() - 1);
+      split.erase(split.end() - 1, split.end());
 
       // We don't want paths with CMakeFiles in them
       // or do we?
@@ -236,13 +237,12 @@ void cmExtraCodeBlocksGenerator::CreateNewProjectFile(
       //
       // Also we can disable external (outside the project) files by setting ON
       // CMAKE_CODEBLOCKS_EXCLUDE_EXTERNAL_FILES variable.
-      const bool excludeExternal =
-        cmIsOn(it.second[0]->GetMakefile()->GetSafeDefinition(
-          "CMAKE_CODEBLOCKS_EXCLUDE_EXTERNAL_FILES"));
-      if (!splitted.empty() &&
+      const bool excludeExternal = it.second[0]->GetMakefile()->IsOn(
+        "CMAKE_CODEBLOCKS_EXCLUDE_EXTERNAL_FILES");
+      if (!split.empty() &&
           (!excludeExternal || (relative.find("..") == std::string::npos)) &&
           relative.find("CMakeFiles") == std::string::npos) {
-        tree.InsertPath(splitted, 1, fileName);
+        tree.InsertPath(split, 1, fileName);
       }
     }
   }
@@ -370,7 +370,7 @@ void cmExtraCodeBlocksGenerator::CreateNewProjectFile(
             std::string lang = s->GetOrDetermineLanguage();
             if (lang == "C" || lang == "CXX" || lang == "CUDA") {
               std::string const& srcext = s->GetExtension();
-              isCFile = cm->IsSourceExtension(srcext);
+              isCFile = cm->IsACLikeSourceExtension(srcext);
             }
 
             std::string const& fullPath = s->ResolveFullPath();
@@ -380,9 +380,8 @@ void cmExtraCodeBlocksGenerator::CreateNewProjectFile(
               cmSystemTools::RelativePath(lg->GetSourceDirectory(), fullPath);
             // Do not add this file if it has ".." in relative path and
             // if CMAKE_CODEBLOCKS_EXCLUDE_EXTERNAL_FILES variable is on.
-            const bool excludeExternal =
-              cmIsOn(lg->GetMakefile()->GetSafeDefinition(
-                "CMAKE_CODEBLOCKS_EXCLUDE_EXTERNAL_FILES"));
+            const bool excludeExternal = lg->GetMakefile()->IsOn(
+              "CMAKE_CODEBLOCKS_EXCLUDE_EXTERNAL_FILES");
             if (excludeExternal &&
                 (relative.find("..") != std::string::npos)) {
               continue;
@@ -498,15 +497,15 @@ void cmExtraCodeBlocksGenerator::AppendTarget(
     if (target->GetType() == cmStateEnums::EXECUTABLE) {
       // Determine the directory where the executable target is created, and
       // set the working directory to this dir.
-      const char* runtimeOutputDir =
+      cmProp runtimeOutputDir =
         makefile->GetDefinition("CMAKE_RUNTIME_OUTPUT_DIRECTORY");
-      if (runtimeOutputDir != nullptr) {
-        workingDir = runtimeOutputDir;
+      if (runtimeOutputDir) {
+        workingDir = *runtimeOutputDir;
       } else {
-        const char* executableOutputDir =
+        cmProp executableOutputDir =
           makefile->GetDefinition("EXECUTABLE_OUTPUT_PATH");
-        if (executableOutputDir != nullptr) {
-          workingDir = executableOutputDir;
+        if (executableOutputDir) {
+          workingDir = *executableOutputDir;
         }
       }
     }
@@ -691,7 +690,8 @@ int cmExtraCodeBlocksGenerator::GetCBTargetType(cmGeneratorTarget* target)
 {
   switch (target->GetType()) {
     case cmStateEnums::EXECUTABLE:
-      if ((target->GetPropertyAsBool("WIN32_EXECUTABLE")) ||
+      if ((target->IsWin32Executable(
+            target->Makefile->GetSafeDefinition("CMAKE_BUILD_TYPE"))) ||
           (target->GetPropertyAsBool("MACOSX_BUNDLE"))) {
         return 0;
       }
diff --git a/Source/cmExtraCodeBlocksGenerator.h b/Source/cmExtraCodeBlocksGenerator.h
index d9f92bd..cada5dd 100644
--- a/Source/cmExtraCodeBlocksGenerator.h
+++ b/Source/cmExtraCodeBlocksGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExtraCodeBlocksGenerator_h
-#define cmExtraCodeBlocksGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -51,5 +50,3 @@ private:
                     const cmLocalGenerator* lg, const std::string& compiler,
                     const std::string& makeFlags);
 };
-
-#endif
diff --git a/Source/cmExtraCodeLiteGenerator.cxx b/Source/cmExtraCodeLiteGenerator.cxx
index bf7555d..95cfb0a 100644
--- a/Source/cmExtraCodeLiteGenerator.cxx
+++ b/Source/cmExtraCodeLiteGenerator.cxx
@@ -227,8 +227,7 @@ std::string cmExtraCodeLiteGenerator::CollectSourceFiles(
           cmSystemTools::LowerCase(s->GetExtension());
         // check whether it is a source or a include file
         // then put it accordingly into one of the two containers
-        if (cm->IsSourceExtension(extLower) || cm->IsCudaExtension(extLower) ||
-            cm->IsFortranExtension(extLower)) {
+        if (cm->IsAKnownSourceExtension(extLower)) {
           cFiles[fullPath] = s;
         } else {
           otherFiles.insert(fullPath);
diff --git a/Source/cmExtraCodeLiteGenerator.h b/Source/cmExtraCodeLiteGenerator.h
index 0ce90b0..2478585 100644
--- a/Source/cmExtraCodeLiteGenerator.h
+++ b/Source/cmExtraCodeLiteGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalCodeLiteGenerator_h
-#define cmGlobalCodeLiteGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -68,5 +67,3 @@ public:
   void CreateNewProjectFile(const cmGeneratorTarget* lg,
                             const std::string& filename);
 };
-
-#endif
diff --git a/Source/cmExtraEclipseCDT4Generator.cxx b/Source/cmExtraEclipseCDT4Generator.cxx
index 7bc4536..ccfd727 100644
--- a/Source/cmExtraEclipseCDT4Generator.cxx
+++ b/Source/cmExtraEclipseCDT4Generator.cxx
@@ -189,9 +189,9 @@ void cmExtraEclipseCDT4Generator::CreateSettingsResourcePrefsFile()
   }
 
   fout << "eclipse.preferences.version=1\n";
-  const char* encoding = mf->GetDefinition("CMAKE_ECLIPSE_RESOURCE_ENCODING");
+  cmProp encoding = mf->GetDefinition("CMAKE_ECLIPSE_RESOURCE_ENCODING");
   if (encoding) {
-    fout << "encoding/<project>=" << encoding << '\n';
+    fout << "encoding/<project>=" << *encoding << '\n';
   }
 }
 
@@ -604,7 +604,7 @@ void cmExtraEclipseCDT4Generator::AppendIncludeDirectories(
 
 void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
 {
-  std::set<std::string> emmited;
+  std::set<std::string> emitted;
 
   const auto& lg = this->GlobalGenerator->GetLocalGenerators()[0];
   const cmMakefile* mf = lg->GetMakefile();
@@ -751,7 +751,7 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
   xml.EndElement();
 
   // add pre-processor definitions to allow eclipse to gray out sections
-  emmited.clear();
+  emitted.clear();
   for (const auto& lgen : this->GlobalGenerator->GetLocalGenerators()) {
 
     if (cmProp cdefs =
@@ -780,8 +780,8 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
         }
 
         // insert the definition if not already added.
-        if (emmited.find(def) == emmited.end()) {
-          emmited.insert(def);
+        if (emitted.find(def) == emitted.end()) {
+          emitted.insert(def);
           xml.StartElement("pathentry");
           xml.Attribute("kind", "mac");
           xml.Attribute("name", def);
@@ -793,11 +793,11 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
     }
   }
   // add system defined c macros
-  const char* cDefs =
+  cmProp cDefs =
     mf->GetDefinition("CMAKE_EXTRA_GENERATOR_C_SYSTEM_DEFINED_MACROS");
   if (this->CEnabled && cDefs) {
     // Expand the list.
-    std::vector<std::string> defs = cmExpandedList(cDefs, true);
+    std::vector<std::string> defs = cmExpandedList(*cDefs, true);
 
     // the list must contain only definition-value pairs:
     if ((defs.size() % 2) == 0) {
@@ -812,8 +812,8 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
         }
 
         // insert the definition if not already added.
-        if (emmited.find(def) == emmited.end()) {
-          emmited.insert(def);
+        if (emitted.find(def) == emitted.end()) {
+          emitted.insert(def);
           xml.StartElement("pathentry");
           xml.Attribute("kind", "mac");
           xml.Attribute("name", def);
@@ -825,11 +825,11 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
     }
   }
   // add system defined c++ macros
-  const char* cxxDefs =
+  cmProp cxxDefs =
     mf->GetDefinition("CMAKE_EXTRA_GENERATOR_CXX_SYSTEM_DEFINED_MACROS");
   if (this->CXXEnabled && cxxDefs) {
     // Expand the list.
-    std::vector<std::string> defs = cmExpandedList(cxxDefs, true);
+    std::vector<std::string> defs = cmExpandedList(*cxxDefs, true);
 
     // the list must contain only definition-value pairs:
     if ((defs.size() % 2) == 0) {
@@ -844,8 +844,8 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
         }
 
         // insert the definition if not already added.
-        if (emmited.find(def) == emmited.end()) {
-          emmited.insert(def);
+        if (emitted.find(def) == emitted.end()) {
+          emitted.insert(def);
           xml.StartElement("pathentry");
           xml.Attribute("kind", "mac");
           xml.Attribute("name", def);
@@ -858,7 +858,7 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
   }
 
   // include dirs
-  emmited.clear();
+  emitted.clear();
   for (const auto& lgen : this->GlobalGenerator->GetLocalGenerators()) {
     const auto& targets = lgen->GetGeneratorTargets();
     for (const auto& target : targets) {
@@ -868,7 +868,7 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
       std::vector<std::string> includeDirs;
       std::string config = mf->GetSafeDefinition("CMAKE_BUILD_TYPE");
       lgen->GetIncludeDirectories(includeDirs, target.get(), "C", config);
-      this->AppendIncludeDirectories(xml, includeDirs, emmited);
+      this->AppendIncludeDirectories(xml, includeDirs, emitted);
     }
   }
   // now also the system include directories, in case we found them in
@@ -879,14 +879,14 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
     std::string systemIncludeDirs =
       mf->GetSafeDefinition("CMAKE_EXTRA_GENERATOR_C_SYSTEM_INCLUDE_DIRS");
     std::vector<std::string> dirs = cmExpandedList(systemIncludeDirs);
-    this->AppendIncludeDirectories(xml, dirs, emmited);
+    this->AppendIncludeDirectories(xml, dirs, emitted);
   }
   compiler = mf->GetSafeDefinition("CMAKE_CXX_COMPILER");
   if (this->CXXEnabled && !compiler.empty()) {
     std::string systemIncludeDirs =
       mf->GetSafeDefinition("CMAKE_EXTRA_GENERATOR_CXX_SYSTEM_INCLUDE_DIRS");
     std::vector<std::string> dirs = cmExpandedList(systemIncludeDirs);
-    this->AppendIncludeDirectories(xml, dirs, emmited);
+    this->AppendIncludeDirectories(xml, dirs, emitted);
   }
 
   xml.EndElement(); // storageModule
@@ -895,7 +895,7 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
   xml.StartElement("storageModule");
   xml.Attribute("moduleId", "org.eclipse.cdt.make.core.buildtargets");
   xml.StartElement("buildTargets");
-  emmited.clear();
+  emitted.clear();
   const std::string& make = mf->GetRequiredDefinition("CMAKE_MAKE_PROGRAM");
   const std::string& makeArgs =
     mf->GetSafeDefinition("CMAKE_ECLIPSE_MAKE_ARGUMENTS");
diff --git a/Source/cmExtraEclipseCDT4Generator.h b/Source/cmExtraEclipseCDT4Generator.h
index a7aa549..c4ed577 100644
--- a/Source/cmExtraEclipseCDT4Generator.h
+++ b/Source/cmExtraEclipseCDT4Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExtraEclipseCDT4Generator_h
-#define cmExtraEclipseCDT4Generator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -106,5 +105,3 @@ private:
   bool CEnabled;
   bool CXXEnabled;
 };
-
-#endif
diff --git a/Source/cmExtraKateGenerator.cxx b/Source/cmExtraKateGenerator.cxx
index 01fac5a..54c3114 100644
--- a/Source/cmExtraKateGenerator.cxx
+++ b/Source/cmExtraKateGenerator.cxx
@@ -13,6 +13,7 @@
 #include "cmGlobalGenerator.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmSourceFile.h"
 #include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
@@ -127,10 +128,10 @@ void cmExtraKateGenerator::WriteTargets(const cmLocalGenerator& lg,
             // only add the "edit_cache" target if it's not ccmake, because
             // this will not work within the IDE
             if (targetName == "edit_cache") {
-              const char* editCommand =
+              cmProp editCommand =
                 localGen->GetMakefile()->GetDefinition("CMAKE_EDIT_COMMAND");
               if (editCommand == nullptr ||
-                  strstr(editCommand, "ccmake") != nullptr) {
+                  strstr(editCommand->c_str(), "ccmake") != nullptr) {
                 insertTarget = false;
               }
             }
diff --git a/Source/cmExtraKateGenerator.h b/Source/cmExtraKateGenerator.h
index 1fb81b4..c66ddbf 100644
--- a/Source/cmExtraKateGenerator.h
+++ b/Source/cmExtraKateGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExtraKateGenerator_h
-#define cmExtraKateGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -43,5 +42,3 @@ private:
   std::string ProjectName;
   bool UseNinja;
 };
-
-#endif
diff --git a/Source/cmExtraSublimeTextGenerator.cxx b/Source/cmExtraSublimeTextGenerator.cxx
index 613a943..3e265a0 100644
--- a/Source/cmExtraSublimeTextGenerator.cxx
+++ b/Source/cmExtraSublimeTextGenerator.cxx
@@ -349,6 +349,13 @@ std::string cmExtraSublimeTextGenerator::ComputeFlagsForObject(
   if (language.empty()) {
     language = "C";
   }
+
+  // explicitly add the explicit language flag before any other flag
+  // this way backwards compatibility with user flags is maintained
+  if (source->GetProperty("LANGUAGE")) {
+    lg->AppendFeatureOptions(flags, language, "EXPLICIT_LANGUAGE");
+  }
+
   std::string const& config =
     lg->GetMakefile()->GetSafeDefinition("CMAKE_BUILD_TYPE");
 
diff --git a/Source/cmExtraSublimeTextGenerator.h b/Source/cmExtraSublimeTextGenerator.h
index 078cfe7..671b65a 100644
--- a/Source/cmExtraSublimeTextGenerator.h
+++ b/Source/cmExtraSublimeTextGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmExtraSublimeTextGenerator_h
-#define cmExtraSublimeTextGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -75,5 +74,3 @@ private:
   bool ExcludeBuildFolder;
   std::string EnvSettings;
 };
-
-#endif
diff --git a/Source/cmFLTKWrapUICommand.h b/Source/cmFLTKWrapUICommand.h
index bb56dbd..7c1fc52 100644
--- a/Source/cmFLTKWrapUICommand.h
+++ b/Source/cmFLTKWrapUICommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFLTKWrapUICommand_h
-#define cmFLTKWrapUICommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmFLTKWrapUICommand(std::vector<std::string> const& args,
                          cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmFSPermissions.h b/Source/cmFSPermissions.h
index fef72e6..78f2240 100644
--- a/Source/cmFSPermissions.h
+++ b/Source/cmFSPermissions.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFSPermissions_h
-#define cmFSPermissions_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -41,5 +40,3 @@ static const mode_t mode_setgid = S_ISGID;
 bool stringToModeT(std::string const& arg, mode_t& permissions);
 
 } // ns
-
-#endif
diff --git a/Source/cmFileAPI.cxx b/Source/cmFileAPI.cxx
index 594969b..c2ab2f1 100644
--- a/Source/cmFileAPI.cxx
+++ b/Source/cmFileAPI.cxx
@@ -665,7 +665,7 @@ std::string cmFileAPI::NoSupportedVersion(
 
 // The "codemodel" object kind.
 
-static unsigned int const CodeModelV2Minor = 1;
+static unsigned int const CodeModelV2Minor = 2;
 
 void cmFileAPI::BuildClientRequestCodeModel(
   ClientRequest& r, std::vector<RequestVersion> const& versions)
diff --git a/Source/cmFileAPI.h b/Source/cmFileAPI.h
index ae07612..086a92a 100644
--- a/Source/cmFileAPI.h
+++ b/Source/cmFileAPI.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileAPI_h
-#define cmFileAPI_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -205,5 +204,3 @@ private:
     ClientRequest& r, std::vector<RequestVersion> const& versions);
   Json::Value BuildInternalTest(Object const& object);
 };
-
-#endif
diff --git a/Source/cmFileAPICMakeFiles.h b/Source/cmFileAPICMakeFiles.h
index 1ae1e4f..5b48ed3 100644
--- a/Source/cmFileAPICMakeFiles.h
+++ b/Source/cmFileAPICMakeFiles.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileAPICMakeFiles_h
-#define cmFileAPICMakeFiles_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -11,5 +10,3 @@ class cmFileAPI;
 
 extern Json::Value cmFileAPICMakeFilesDump(cmFileAPI& fileAPI,
                                            unsigned long version);
-
-#endif
diff --git a/Source/cmFileAPICache.h b/Source/cmFileAPICache.h
index 2f30c76..bd9feeb 100644
--- a/Source/cmFileAPICache.h
+++ b/Source/cmFileAPICache.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileAPICache_h
-#define cmFileAPICache_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -11,5 +10,3 @@ class cmFileAPI;
 
 extern Json::Value cmFileAPICacheDump(cmFileAPI& fileAPI,
                                       unsigned long version);
-
-#endif
diff --git a/Source/cmFileAPICodemodel.cxx b/Source/cmFileAPICodemodel.cxx
index fe331ec..4a53c8a 100644
--- a/Source/cmFileAPICodemodel.cxx
+++ b/Source/cmFileAPICodemodel.cxx
@@ -175,6 +175,38 @@ public:
   }
 };
 
+template <typename T>
+class JBTs
+{
+public:
+  JBTs(T v = T(), std::vector<JBTIndex> ids = std::vector<JBTIndex>())
+    : Value(std::move(v))
+    , Backtraces(std::move(ids))
+  {
+  }
+  T Value;
+  std::vector<JBTIndex> Backtraces;
+  friend bool operator==(JBTs<T> const& l, JBTs<T> const& r)
+  {
+    if ((l.Value == r.Value) && (l.Backtraces.size() == r.Backtraces.size())) {
+      for (size_t i = 0; i < l.Backtraces.size(); i++) {
+        if (l.Backtraces[i].Index != r.Backtraces[i].Index) {
+          return false;
+        }
+      }
+    }
+    return true;
+  }
+  static bool ValueEq(JBTs<T> const& l, JBTs<T> const& r)
+  {
+    return l.Value == r.Value;
+  }
+  static bool ValueLess(JBTs<T> const& l, JBTs<T> const& r)
+  {
+    return l.Value < r.Value;
+  }
+};
+
 class BacktraceData
 {
   std::string TopSource;
@@ -277,6 +309,7 @@ struct CompileData
 
   std::string Language;
   std::string Sysroot;
+  JBTs<std::string> LanguageStandard;
   std::vector<JBT<std::string>> Flags;
   std::vector<JBT<std::string>> Defines;
   std::vector<JBT<std::string>> PrecompileHeaders;
@@ -287,6 +320,7 @@ struct CompileData
     return (l.Language == r.Language && l.Sysroot == r.Sysroot &&
             l.Flags == r.Flags && l.Defines == r.Defines &&
             l.PrecompileHeaders == r.PrecompileHeaders &&
+            l.LanguageStandard == r.LanguageStandard &&
             l.Includes == r.Includes);
   }
 };
@@ -320,6 +354,12 @@ struct hash<CompileData>
       result = result ^ hash<std::string>()(i.Value) ^
         hash<Json::ArrayIndex>()(i.Backtrace.Index);
     }
+    if (!in.LanguageStandard.Value.empty()) {
+      result = result ^ hash<std::string>()(in.LanguageStandard.Value);
+      for (JBTIndex backtrace : in.LanguageStandard.Backtraces) {
+        result = result ^ hash<Json::ArrayIndex>()(backtrace.Index);
+      }
+    }
     return result;
   }
 };
@@ -363,6 +403,16 @@ class Target
     return JBT<T>(bt.Value, this->Backtraces.Add(bt.Backtrace));
   }
 
+  template <typename T>
+  JBTs<T> ToJBTs(BTs<T> const& bts)
+  {
+    std::vector<JBTIndex> ids;
+    for (cmListFileBacktrace const& backtrace : bts.Backtraces) {
+      ids.emplace_back(this->Backtraces.Add(backtrace));
+    }
+    return JBTs<T>(bts.Value, ids);
+  }
+
   void ProcessLanguages();
   void ProcessLanguage(std::string const& lang);
 
@@ -377,6 +427,7 @@ class Target
   Json::Value DumpCompileData(CompileData const& cd);
   Json::Value DumpInclude(CompileData::IncludeEntry const& inc);
   Json::Value DumpPrecompileHeader(JBT<std::string> const& header);
+  Json::Value DumpLanguageStandard(JBTs<std::string> const& standard);
   Json::Value DumpDefine(JBT<std::string> const& def);
   Json::Value DumpSources();
   Json::Value DumpSource(cmGeneratorTarget::SourceAndKind const& sk,
@@ -438,7 +489,7 @@ Json::Value Codemodel::DumpConfigurations()
   const auto& makefiles = gg->GetMakefiles();
   if (!makefiles.empty()) {
     std::vector<std::string> const& configs =
-      makefiles[0]->GetGeneratorConfigs();
+      makefiles[0]->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
     for (std::string const& config : configs) {
       configurations.append(this->DumpConfiguration(config));
     }
@@ -574,7 +625,7 @@ Json::Value CodemodelConfig::DumpTargets()
 
   for (cmGeneratorTarget* gt : targetList) {
     if (gt->GetType() == cmStateEnums::GLOBAL_TARGET ||
-        gt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+        !gt->IsInBuildSystem()) {
       continue;
     }
 
@@ -801,12 +852,12 @@ void Target::ProcessLanguage(std::string const& lang)
 {
   CompileData& cd = this->CompileDataMap[lang];
   cd.Language = lang;
-  if (const char* sysrootCompile =
+  if (cmProp sysrootCompile =
         this->GT->Makefile->GetDefinition("CMAKE_SYSROOT_COMPILE")) {
-    cd.Sysroot = sysrootCompile;
-  } else if (const char* sysroot =
+    cd.Sysroot = *sysrootCompile;
+  } else if (cmProp sysroot =
                this->GT->Makefile->GetDefinition("CMAKE_SYSROOT")) {
-    cd.Sysroot = sysroot;
+    cd.Sysroot = *sysroot;
   }
   cmLocalGenerator* lg = this->GT->GetLocalGenerator();
   {
@@ -838,6 +889,11 @@ void Target::ProcessLanguage(std::string const& lang)
   for (BT<std::string> const& pch : precompileHeaders) {
     cd.PrecompileHeaders.emplace_back(this->ToJBT(pch));
   }
+  BTs<std::string> const* languageStandard =
+    this->GT->GetLanguageStandardProperty(lang, this->Config);
+  if (languageStandard) {
+    cd.LanguageStandard = this->ToJBTs(*languageStandard);
+  }
 }
 
 Json::ArrayIndex Target::AddSourceGroup(cmSourceGroup* sg, Json::ArrayIndex si)
@@ -996,6 +1052,9 @@ CompileData Target::MergeCompileData(CompileData const& fd)
   // All compile groups share the precompile headers of the target.
   cd.PrecompileHeaders = td.PrecompileHeaders;
 
+  // All compile groups share the language standard of the target.
+  cd.LanguageStandard = td.LanguageStandard;
+
   // Use target-wide flags followed by source-specific flags.
   cd.Flags.reserve(td.Flags.size() + fd.Flags.size());
   cd.Flags.insert(cd.Flags.end(), td.Flags.begin(), td.Flags.end());
@@ -1153,6 +1212,10 @@ Json::Value Target::DumpCompileData(CompileData const& cd)
     }
     result["precompileHeaders"] = std::move(precompileHeaders);
   }
+  if (!cd.LanguageStandard.Value.empty()) {
+    result["languageStandard"] =
+      this->DumpLanguageStandard(cd.LanguageStandard);
+  }
 
   return result;
 }
@@ -1176,6 +1239,20 @@ Json::Value Target::DumpPrecompileHeader(JBT<std::string> const& header)
   return precompileHeader;
 }
 
+Json::Value Target::DumpLanguageStandard(JBTs<std::string> const& standard)
+{
+  Json::Value languageStandard = Json::objectValue;
+  languageStandard["standard"] = standard.Value;
+  if (!standard.Backtraces.empty()) {
+    Json::Value backtraces = Json::arrayValue;
+    for (JBTIndex backtrace : standard.Backtraces) {
+      backtraces.append(backtrace.Index);
+    }
+    languageStandard["backtraces"] = backtraces;
+  }
+  return languageStandard;
+}
+
 Json::Value Target::DumpDefine(JBT<std::string> const& def)
 {
   Json::Value define = Json::objectValue;
@@ -1327,12 +1404,12 @@ Json::Value Target::DumpLink()
       link["commandFragments"] = std::move(commandFragments);
     }
   }
-  if (const char* sysrootLink =
+  if (cmProp sysrootLink =
         this->GT->Makefile->GetDefinition("CMAKE_SYSROOT_LINK")) {
-    link["sysroot"] = this->DumpSysroot(sysrootLink);
-  } else if (const char* sysroot =
+    link["sysroot"] = this->DumpSysroot(*sysrootLink);
+  } else if (cmProp sysroot =
                this->GT->Makefile->GetDefinition("CMAKE_SYSROOT")) {
-    link["sysroot"] = this->DumpSysroot(sysroot);
+    link["sysroot"] = this->DumpSysroot(*sysroot);
   }
   if (this->GT->IsIPOEnabled(lang, this->Config)) {
     link["lto"] = true;
diff --git a/Source/cmFileAPICodemodel.h b/Source/cmFileAPICodemodel.h
index a6c6bdd..263f675 100644
--- a/Source/cmFileAPICodemodel.h
+++ b/Source/cmFileAPICodemodel.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileAPICodemodel_h
-#define cmFileAPICodemodel_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -11,5 +10,3 @@ class cmFileAPI;
 
 extern Json::Value cmFileAPICodemodelDump(cmFileAPI& fileAPI,
                                           unsigned long version);
-
-#endif
diff --git a/Source/cmFileCommand.cxx b/Source/cmFileCommand.cxx
index 7101e22..84639a7 100644
--- a/Source/cmFileCommand.cxx
+++ b/Source/cmFileCommand.cxx
@@ -28,8 +28,10 @@
 
 #include "cmAlgorithms.h"
 #include "cmArgumentParser.h"
+#include "cmCMakePath.h"
 #include "cmCryptoHash.h"
 #include "cmExecutionStatus.h"
+#include "cmFSPermissions.h"
 #include "cmFileCopier.h"
 #include "cmFileInstaller.h"
 #include "cmFileLockPool.h"
@@ -43,6 +45,7 @@
 #include "cmMessageType.h"
 #include "cmNewLineStyle.h"
 #include "cmPolicies.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmRuntimeDependencyArchive.h"
 #include "cmState.h"
@@ -1232,6 +1235,50 @@ bool HandleInstallCommand(std::vector<std::string> const& args,
   return installer.Run(args);
 }
 
+bool HandleRealPathCommand(std::vector<std::string> const& args,
+                           cmExecutionStatus& status)
+{
+  if (args.size() < 3) {
+    status.SetError("REAL_PATH requires a path and an output variable");
+    return false;
+  }
+
+  struct Arguments
+  {
+    std::string BaseDirectory;
+  };
+  static auto const parser = cmArgumentParser<Arguments>{}.Bind(
+    "BASE_DIRECTORY"_s, &Arguments::BaseDirectory);
+
+  std::vector<std::string> unparsedArguments;
+  std::vector<std::string> keywordsMissingValue;
+  std::vector<std::string> parsedKeywords;
+  auto arguments =
+    parser.Parse(cmMakeRange(args).advance(3), &unparsedArguments,
+                 &keywordsMissingValue, &parsedKeywords);
+
+  if (!unparsedArguments.empty()) {
+    status.SetError("REAL_PATH called with unexpected arguments");
+    return false;
+  }
+  if (!keywordsMissingValue.empty()) {
+    status.SetError("BASE_DIRECTORY requires a value");
+    return false;
+  }
+
+  if (parsedKeywords.empty()) {
+    arguments.BaseDirectory = status.GetMakefile().GetCurrentSourceDirectory();
+  }
+
+  cmCMakePath path(args[1]);
+  path = path.Absolute(arguments.BaseDirectory).Normal();
+  auto realPath = cmSystemTools::GetRealPath(path.GenericString());
+
+  status.GetMakefile().AddDefinition(args[2], realPath);
+
+  return true;
+}
+
 bool HandleRelativePathCommand(std::vector<std::string> const& args,
                                cmExecutionStatus& status)
 {
@@ -1394,8 +1441,10 @@ size_t cmWriteToFileCallback(void* ptr, size_t size, size_t nmemb, void* data)
 {
   int realsize = static_cast<int>(size * nmemb);
   cmsys::ofstream* fout = static_cast<cmsys::ofstream*>(data);
-  const char* chPtr = static_cast<char*>(ptr);
-  fout->write(chPtr, realsize);
+  if (fout) {
+    const char* chPtr = static_cast<char*>(ptr);
+    fout->write(chPtr, realsize);
+  }
   return realsize;
 }
 
@@ -1551,22 +1600,21 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
 {
 #if !defined(CMAKE_BOOTSTRAP)
   auto i = args.begin();
-  if (args.size() < 3) {
-    status.SetError("DOWNLOAD must be called with at least three arguments.");
+  if (args.size() < 2) {
+    status.SetError("DOWNLOAD must be called with at least two arguments.");
     return false;
   }
   ++i; // Get rid of subcommand
   std::string url = *i;
   ++i;
-  std::string file = *i;
-  ++i;
+  std::string file;
 
   long timeout = 0;
   long inactivity_timeout = 0;
   std::string logVar;
   std::string statusVar;
   bool tls_verify = status.GetMakefile().IsOn("CMAKE_TLS_VERIFY");
-  const char* cainfo = status.GetMakefile().GetDefinition("CMAKE_TLS_CAINFO");
+  cmProp cainfo = status.GetMakefile().GetDefinition("CMAKE_TLS_CAINFO");
   std::string netrc_level =
     status.GetMakefile().GetSafeDefinition("CMAKE_NETRC");
   std::string netrc_file =
@@ -1621,7 +1669,7 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
     } else if (*i == "TLS_CAINFO") {
       ++i;
       if (i != args.end()) {
-        cainfo = i->c_str();
+        cainfo = &(*i);
       } else {
         status.SetError("DOWNLOAD missing file value for TLS_CAINFO.");
         return false;
@@ -1690,6 +1738,8 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
         return false;
       }
       curl_headers.push_back(*i);
+    } else if (file.empty()) {
+      file = *i;
     } else {
       // Do not return error for compatibility reason.
       std::string err = cmStrCat("Unexpected argument: ", *i);
@@ -1697,11 +1747,18 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
     }
     ++i;
   }
+  // Can't calculate hash if we don't save the file.
+  // TODO Incrementally calculate hash in the write callback as the file is
+  // being downloaded so this check can be relaxed.
+  if (file.empty() && hash) {
+    status.SetError("DOWNLOAD cannot calculate hash if file is not saved.");
+    return false;
+  }
   // If file exists already, and caller specified an expected md5 or sha,
   // and the existing file already has the expected hash, then simply
   // return.
   //
-  if (cmSystemTools::FileExists(file) && hash.get()) {
+  if (!file.empty() && cmSystemTools::FileExists(file) && hash.get()) {
     std::string msg;
     std::string actualHash = hash->HashFile(file);
     if (actualHash == expectedHash) {
@@ -1716,20 +1773,26 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
   // Make sure parent directory exists so we can write to the file
   // as we receive downloaded bits from curl...
   //
-  std::string dir = cmSystemTools::GetFilenamePath(file);
-  if (!dir.empty() && !cmSystemTools::FileExists(dir) &&
-      !cmSystemTools::MakeDirectory(dir)) {
-    std::string errstring = "DOWNLOAD error: cannot create directory '" + dir +
-      "' - Specify file by full path name and verify that you "
-      "have directory creation and file write privileges.";
-    status.SetError(errstring);
-    return false;
+  if (!file.empty()) {
+    std::string dir = cmSystemTools::GetFilenamePath(file);
+    if (!dir.empty() && !cmSystemTools::FileExists(dir) &&
+        !cmSystemTools::MakeDirectory(dir)) {
+      std::string errstring = "DOWNLOAD error: cannot create directory '" +
+        dir +
+        "' - Specify file by full path name and verify that you "
+        "have directory creation and file write privileges.";
+      status.SetError(errstring);
+      return false;
+    }
   }
 
-  cmsys::ofstream fout(file.c_str(), std::ios::binary);
-  if (!fout) {
-    status.SetError("DOWNLOAD cannot open file for write.");
-    return false;
+  cmsys::ofstream fout;
+  if (!file.empty()) {
+    fout.open(file.c_str(), std::ios::binary);
+    if (!fout) {
+      status.SetError("DOWNLOAD cannot open file for write.");
+      return false;
+    }
   }
 
 #  if defined(_WIN32)
@@ -1773,7 +1836,7 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
 
   // check to see if a CAINFO file has been specified
   // command arg comes first
-  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cainfo);
+  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cmToCStr(cainfo));
   if (!cainfo_err.empty()) {
     status.SetError(cainfo_err);
     return false;
@@ -1791,7 +1854,8 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
 
   cmFileCommandVectorOfChar chunkDebug;
 
-  res = ::curl_easy_setopt(curl, CURLOPT_WRITEDATA, &fout);
+  res = ::curl_easy_setopt(curl, CURLOPT_WRITEDATA,
+                           file.empty() ? nullptr : &fout);
   check_curl_result(res, "DOWNLOAD cannot set write data: ");
 
   res = ::curl_easy_setopt(curl, CURLOPT_DEBUGDATA, &chunkDebug);
@@ -1865,8 +1929,10 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
 
   // Explicitly flush/close so we can measure the md5 accurately.
   //
-  fout.flush();
-  fout.close();
+  if (!file.empty()) {
+    fout.flush();
+    fout.close();
+  }
 
   // Verify MD5 sum if requested:
   //
@@ -1936,7 +2002,7 @@ bool HandleUploadCommand(std::vector<std::string> const& args,
   std::string statusVar;
   bool showProgress = false;
   bool tls_verify = status.GetMakefile().IsOn("CMAKE_TLS_VERIFY");
-  const char* cainfo = status.GetMakefile().GetDefinition("CMAKE_TLS_CAINFO");
+  cmProp cainfo = status.GetMakefile().GetDefinition("CMAKE_TLS_CAINFO");
   std::string userpwd;
   std::string netrc_level =
     status.GetMakefile().GetSafeDefinition("CMAKE_NETRC");
@@ -1989,7 +2055,7 @@ bool HandleUploadCommand(std::vector<std::string> const& args,
     } else if (*i == "TLS_CAINFO") {
       ++i;
       if (i != args.end()) {
-        cainfo = i->c_str();
+        cainfo = &(*i);
       } else {
         status.SetError("UPLOAD missing file value for TLS_CAINFO.");
         return false;
@@ -2090,7 +2156,7 @@ bool HandleUploadCommand(std::vector<std::string> const& args,
 
   // check to see if a CAINFO file has been specified
   // command arg comes first
-  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cainfo);
+  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cmToCStr(cainfo));
   if (!cainfo_err.empty()) {
     status.SetError(cainfo_err);
     return false;
@@ -2221,6 +2287,7 @@ bool HandleUploadCommand(std::vector<std::string> const& args,
 }
 
 void AddEvaluationFile(const std::string& inputName,
+                       const std::string& targetName,
                        const std::string& outputExpr,
                        const std::string& condition, bool inputIsContent,
                        cmExecutionStatus& status)
@@ -2236,7 +2303,8 @@ void AddEvaluationFile(const std::string& inputName,
     conditionGe.Parse(condition);
 
   status.GetMakefile().AddEvaluationFile(
-    inputName, std::move(outputCge), std::move(conditionCge), inputIsContent);
+    inputName, targetName, std::move(outputCge), std::move(conditionCge),
+    inputIsContent);
 }
 
 bool HandleGenerateCommand(std::vector<std::string> const& args,
@@ -2250,23 +2318,36 @@ bool HandleGenerateCommand(std::vector<std::string> const& args,
     status.SetError("Incorrect arguments to GENERATE subcommand.");
     return false;
   }
+
   std::string condition;
-  if (args.size() > 5) {
-    if (args[5] != "CONDITION") {
+  std::string target;
+
+  for (std::size_t i = 5; i < args.size();) {
+    const std::string& arg = args[i++];
+
+    if (args.size() - i == 0) {
       status.SetError("Incorrect arguments to GENERATE subcommand.");
       return false;
     }
-    if (args.size() != 7) {
-      status.SetError("Incorrect arguments to GENERATE subcommand.");
+
+    const std::string& value = args[i++];
+
+    if (value.empty()) {
+      status.SetError(
+        arg + " of sub-command GENERATE must not be empty if specified.");
       return false;
     }
-    condition = args[6];
-    if (condition.empty()) {
-      status.SetError("CONDITION of sub-command GENERATE must not be empty if "
-                      "specified.");
+
+    if (arg == "CONDITION") {
+      condition = value;
+    } else if (arg == "TARGET") {
+      target = value;
+    } else {
+      status.SetError("Unknown argument to GENERATE subcommand.");
       return false;
     }
   }
+
   std::string output = args[2];
   const bool inputIsContent = args[3] != "INPUT";
   if (inputIsContent && args[3] != "CONTENT") {
@@ -2275,7 +2356,7 @@ bool HandleGenerateCommand(std::vector<std::string> const& args,
   }
   std::string input = args[4];
 
-  AddEvaluationFile(input, output, condition, inputIsContent, status);
+  AddEvaluationFile(input, target, output, condition, inputIsContent, status);
   return true;
 }
 
@@ -2918,7 +2999,7 @@ bool HandleConfigureCommand(std::vector<std::string> const& args,
   }
   fout.SetCopyIfDifferent(true);
 
-  // copy intput to output and expand variables from input at the same time
+  // copy input to output and expand variables from input at the same time
   std::stringstream sin(input, std::ios::in);
   std::string inLine;
   std::string outLine;
@@ -3126,6 +3207,163 @@ bool HandleArchiveExtractCommand(std::vector<std::string> const& args,
   return true;
 }
 
+bool ValidateAndConvertPermissions(const std::vector<std::string>& permissions,
+                                   mode_t& perms, cmExecutionStatus& status)
+{
+  for (const auto& i : permissions) {
+    if (!cmFSPermissions::stringToModeT(i, perms)) {
+      status.SetError(i + " is an invalid permission specifier");
+      cmSystemTools::SetFatalErrorOccured();
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SetPermissions(const std::string& filename, const mode_t& perms,
+                    cmExecutionStatus& status)
+{
+  if (!cmSystemTools::SetPermissions(filename, perms)) {
+    status.SetError("Failed to set permissions for " + filename);
+    cmSystemTools::SetFatalErrorOccured();
+    return false;
+  }
+  return true;
+}
+
+bool HandleChmodCommandImpl(std::vector<std::string> const& args, bool recurse,
+                            cmExecutionStatus& status)
+{
+  mode_t perms = 0;
+  mode_t fperms = 0;
+  mode_t dperms = 0;
+  cmsys::Glob globber;
+
+  globber.SetRecurse(recurse);
+  globber.SetRecurseListDirs(recurse);
+
+  struct Arguments
+  {
+    std::vector<std::string> Permissions;
+    std::vector<std::string> FilePermissions;
+    std::vector<std::string> DirectoryPermissions;
+  };
+
+  static auto const parser =
+    cmArgumentParser<Arguments>{}
+      .Bind("PERMISSIONS"_s, &Arguments::Permissions)
+      .Bind("FILE_PERMISSIONS"_s, &Arguments::FilePermissions)
+      .Bind("DIRECTORY_PERMISSIONS"_s, &Arguments::DirectoryPermissions);
+
+  std::vector<std::string> pathEntries;
+  std::vector<std::string> keywordsMissingValues;
+  Arguments parsedArgs = parser.Parse(cmMakeRange(args).advance(1),
+                                      &pathEntries, &keywordsMissingValues);
+
+  // check validity of arguments
+  if (parsedArgs.Permissions.empty() && parsedArgs.FilePermissions.empty() &&
+      parsedArgs.DirectoryPermissions.empty()) // no permissions given
+  {
+    status.SetError("No permissions given");
+    cmSystemTools::SetFatalErrorOccured();
+    return false;
+  }
+
+  if (!parsedArgs.Permissions.empty() && !parsedArgs.FilePermissions.empty() &&
+      !parsedArgs.DirectoryPermissions.empty()) // all keywords are used
+  {
+    status.SetError("Remove either PERMISSIONS or FILE_PERMISSIONS or "
+                    "DIRECTORY_PERMISSIONS from the invocation");
+    cmSystemTools::SetFatalErrorOccured();
+    return false;
+  }
+
+  if (!keywordsMissingValues.empty()) {
+    for (const auto& i : keywordsMissingValues) {
+      status.SetError(i + " is not given any arguments");
+      cmSystemTools::SetFatalErrorOccured();
+    }
+    return false;
+  }
+
+  // validate permissions
+  bool validatePermissions =
+    ValidateAndConvertPermissions(parsedArgs.Permissions, perms, status) &&
+    ValidateAndConvertPermissions(parsedArgs.FilePermissions, fperms,
+                                  status) &&
+    ValidateAndConvertPermissions(parsedArgs.DirectoryPermissions, dperms,
+                                  status);
+  if (!validatePermissions) {
+    return false;
+  }
+
+  std::vector<std::string> allPathEntries;
+
+  if (recurse) {
+    std::vector<std::string> tempPathEntries;
+    for (const auto& i : pathEntries) {
+      if (cmSystemTools::FileIsDirectory(i)) {
+        globber.FindFiles(i + "/*");
+        tempPathEntries = globber.GetFiles();
+        allPathEntries.insert(allPathEntries.end(), tempPathEntries.begin(),
+                              tempPathEntries.end());
+        allPathEntries.emplace_back(i);
+      } else {
+        allPathEntries.emplace_back(i); // We validate path entries below
+      }
+    }
+  } else {
+    allPathEntries = std::move(pathEntries);
+  }
+
+  // chmod
+  for (const auto& i : allPathEntries) {
+    if (!(cmSystemTools::FileExists(i) || cmSystemTools::FileIsDirectory(i))) {
+      status.SetError(cmStrCat("does not exist:\n  ", i));
+      cmSystemTools::SetFatalErrorOccured();
+      return false;
+    }
+
+    if (cmSystemTools::FileExists(i, true)) {
+      bool success = true;
+      const mode_t& filePermissions =
+        parsedArgs.FilePermissions.empty() ? perms : fperms;
+      if (filePermissions) {
+        success = SetPermissions(i, filePermissions, status);
+      }
+      if (!success) {
+        return false;
+      }
+    }
+
+    else if (cmSystemTools::FileIsDirectory(i)) {
+      bool success = true;
+      const mode_t& directoryPermissions =
+        parsedArgs.DirectoryPermissions.empty() ? perms : dperms;
+      if (directoryPermissions) {
+        success = SetPermissions(i, directoryPermissions, status);
+      }
+      if (!success) {
+        return false;
+      }
+    }
+  }
+
+  return true;
+}
+
+bool HandleChmodCommand(std::vector<std::string> const& args,
+                        cmExecutionStatus& status)
+{
+  return HandleChmodCommandImpl(args, false, status);
+}
+
+bool HandleChmodRecurseCommand(std::vector<std::string> const& args,
+                               cmExecutionStatus& status)
+{
+  return HandleChmodCommandImpl(args, true, status);
+}
+
 } // namespace
 
 bool cmFileCommand(std::vector<std::string> const& args,
@@ -3167,6 +3405,7 @@ bool cmFileCommand(std::vector<std::string> const& args,
     { "RPATH_CHECK"_s, HandleRPathCheckCommand },
     { "RPATH_REMOVE"_s, HandleRPathRemoveCommand },
     { "READ_ELF"_s, HandleReadElfCommand },
+    { "REAL_PATH"_s, HandleRealPathCommand },
     { "RELATIVE_PATH"_s, HandleRelativePathCommand },
     { "TO_CMAKE_PATH"_s, HandleCMakePathCommand },
     { "TO_NATIVE_PATH"_s, HandleNativePathCommand },
@@ -3182,6 +3421,8 @@ bool cmFileCommand(std::vector<std::string> const& args,
     { "CONFIGURE"_s, HandleConfigureCommand },
     { "ARCHIVE_CREATE"_s, HandleArchiveCreateCommand },
     { "ARCHIVE_EXTRACT"_s, HandleArchiveExtractCommand },
+    { "CHMOD"_s, HandleChmodCommand },
+    { "CHMOD_RECURSE"_s, HandleChmodRecurseCommand },
   };
 
   return subcommand(args[0], args, status);
diff --git a/Source/cmFileCommand.h b/Source/cmFileCommand.h
index 8c9b219..ec9ee47 100644
--- a/Source/cmFileCommand.h
+++ b/Source/cmFileCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileCommand_h
-#define cmFileCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmFileCommand(std::vector<std::string> const& args,
                    cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmFileCopier.cxx b/Source/cmFileCopier.cxx
index 627e05b..48fc286 100644
--- a/Source/cmFileCopier.cxx
+++ b/Source/cmFileCopier.cxx
@@ -10,6 +10,7 @@
 #include "cmFSPermissions.h"
 #include "cmFileTimes.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 
@@ -171,11 +172,11 @@ void cmFileCopier::DefaultDirectoryPermissions()
 bool cmFileCopier::GetDefaultDirectoryPermissions(mode_t** mode)
 {
   // check if default dir creation permissions were set
-  const char* default_dir_install_permissions = this->Makefile->GetDefinition(
+  cmProp default_dir_install_permissions = this->Makefile->GetDefinition(
     "CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS");
-  if (default_dir_install_permissions && *default_dir_install_permissions) {
+  if (cmNonempty(default_dir_install_permissions)) {
     std::vector<std::string> items =
-      cmExpandedList(default_dir_install_permissions);
+      cmExpandedList(*default_dir_install_permissions);
     for (const auto& arg : items) {
       if (!this->CheckPermissions(arg, **mode)) {
         this->Status.SetError(
diff --git a/Source/cmFileCopier.h b/Source/cmFileCopier.h
index 612a57f..217d58d 100644
--- a/Source/cmFileCopier.h
+++ b/Source/cmFileCopier.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileCopier_h
-#define cmFileCopier_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -120,5 +119,3 @@ protected:
 
   bool GetDefaultDirectoryPermissions(mode_t** mode);
 };
-
-#endif
diff --git a/Source/cmFileInstaller.h b/Source/cmFileInstaller.h
index 537cd53..3a905d3 100644
--- a/Source/cmFileInstaller.h
+++ b/Source/cmFileInstaller.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileInstaller_h
-#define cmFileInstaller_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -50,5 +49,3 @@ protected:
   bool GetTargetTypeFromString(const std::string& stype);
   bool HandleInstallDestination();
 };
-
-#endif
diff --git a/Source/cmFileLock.h b/Source/cmFileLock.h
index 5fe068e..2b125af 100644
--- a/Source/cmFileLock.h
+++ b/Source/cmFileLock.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileLock_h
-#define cmFileLock_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -63,5 +62,3 @@ private:
 
   std::string Filename;
 };
-
-#endif // cmFileLock_h
diff --git a/Source/cmFileLockPool.h b/Source/cmFileLockPool.h
index d45c82c..f2f9f23 100644
--- a/Source/cmFileLockPool.h
+++ b/Source/cmFileLockPool.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileLockPool_h
-#define cmFileLockPool_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -86,5 +85,3 @@ private:
   List FileScopes;
   ScopePool ProcessScope;
 };
-
-#endif // cmFileLockPool_h
diff --git a/Source/cmFileLockResult.h b/Source/cmFileLockResult.h
index 81c1906..8a58d1f 100644
--- a/Source/cmFileLockResult.h
+++ b/Source/cmFileLockResult.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileLockResult_h
-#define cmFileLockResult_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -73,5 +72,3 @@ private:
   ErrorType Type;
   Error ErrorValue;
 };
-
-#endif // cmFileLockResult_h
diff --git a/Source/cmFilePathChecksum.h b/Source/cmFilePathChecksum.h
index b7d5cd2..a6f7bd3 100644
--- a/Source/cmFilePathChecksum.h
+++ b/Source/cmFilePathChecksum.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFilePathChecksum_h
-#define cmFilePathChecksum_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -60,5 +59,3 @@ private:
   /// List of (directory name, seed name) pairs
   std::array<std::pair<std::string, std::string>, 4> parentDirs;
 };
-
-#endif
diff --git a/Source/cmFileTime.h b/Source/cmFileTime.h
index e9a8559..f496cdc 100644
--- a/Source/cmFileTime.h
+++ b/Source/cmFileTime.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileTime_h
-#define cmFileTime_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -126,5 +125,3 @@ public:
 private:
   NSC NS = 0;
 };
-
-#endif
diff --git a/Source/cmFileTimeCache.h b/Source/cmFileTimeCache.h
index 83b77b6..336136e 100644
--- a/Source/cmFileTimeCache.h
+++ b/Source/cmFileTimeCache.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileTimeCache_h
-#define cmFileTimeCache_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -53,5 +52,3 @@ public:
 private:
   std::unordered_map<std::string, cmFileTime> Cache;
 };
-
-#endif
diff --git a/Source/cmFileTimes.h b/Source/cmFileTimes.h
index 191d89e..f1916f7 100644
--- a/Source/cmFileTimes.h
+++ b/Source/cmFileTimes.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFileTimes_h
-#define cmFileTimes_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -36,5 +35,3 @@ private:
   class Times;
   std::unique_ptr<Times> times;
 };
-
-#endif
diff --git a/Source/cmFindBase.cxx b/Source/cmFindBase.cxx
index 743ac75..bf52d75 100644
--- a/Source/cmFindBase.cxx
+++ b/Source/cmFindBase.cxx
@@ -294,11 +294,10 @@ void cmFindBase::FillUserGuessPath()
 
 bool cmFindBase::CheckForVariableInCache()
 {
-  if (const char* cacheValue =
-        this->Makefile->GetDefinition(this->VariableName)) {
+  if (cmProp cacheValue = this->Makefile->GetDefinition(this->VariableName)) {
     cmState* state = this->Makefile->GetState();
     cmProp cacheEntry = state->GetCacheEntryValue(this->VariableName);
-    bool found = !cmIsNOTFOUND(cacheValue);
+    bool found = !cmIsNOTFOUND(*cacheValue);
     bool cached = cacheEntry != nullptr;
     if (found) {
       // If the user specifies the entry on the command line without a
diff --git a/Source/cmFindBase.h b/Source/cmFindBase.h
index 4cbf09e..57a40be 100644
--- a/Source/cmFindBase.h
+++ b/Source/cmFindBase.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFindBase_h
-#define cmFindBase_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -94,5 +93,3 @@ private:
   std::vector<DebugLibState> FailedSearchLocations;
   DebugLibState FoundSearchLocation;
 };
-
-#endif
diff --git a/Source/cmFindCommon.cxx b/Source/cmFindCommon.cxx
index 3e97150..dee91d7 100644
--- a/Source/cmFindCommon.cxx
+++ b/Source/cmFindCommon.cxx
@@ -11,6 +11,7 @@
 #include "cmExecutionStatus.h"
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 #include "cmake.h"
@@ -182,9 +183,9 @@ void cmFindCommon::SelectDefaultSearchModes()
   };
 
   for (auto& path : search_paths) {
-    const char* def = this->Makefile->GetDefinition(path.second);
+    cmProp def = this->Makefile->GetDefinition(path.second);
     if (def) {
-      path.first = !cmIsOn(def);
+      path.first = !cmIsOn(*def);
     }
   }
 }
@@ -202,16 +203,15 @@ void cmFindCommon::RerootPaths(std::vector<std::string>& paths)
     return;
   }
 
-  const char* sysroot = this->Makefile->GetDefinition("CMAKE_SYSROOT");
-  const char* sysrootCompile =
+  cmProp sysroot = this->Makefile->GetDefinition("CMAKE_SYSROOT");
+  cmProp sysrootCompile =
     this->Makefile->GetDefinition("CMAKE_SYSROOT_COMPILE");
-  const char* sysrootLink =
-    this->Makefile->GetDefinition("CMAKE_SYSROOT_LINK");
-  const char* rootPath = this->Makefile->GetDefinition("CMAKE_FIND_ROOT_PATH");
-  const bool noSysroot = !sysroot || !*sysroot;
-  const bool noCompileSysroot = !sysrootCompile || !*sysrootCompile;
-  const bool noLinkSysroot = !sysrootLink || !*sysrootLink;
-  const bool noRootPath = !rootPath || !*rootPath;
+  cmProp sysrootLink = this->Makefile->GetDefinition("CMAKE_SYSROOT_LINK");
+  cmProp rootPath = this->Makefile->GetDefinition("CMAKE_FIND_ROOT_PATH");
+  const bool noSysroot = !cmNonempty(sysroot);
+  const bool noCompileSysroot = !cmNonempty(sysrootCompile);
+  const bool noLinkSysroot = !cmNonempty(sysrootLink);
+  const bool noRootPath = !cmNonempty(rootPath);
   if (noSysroot && noCompileSysroot && noLinkSysroot && noRootPath) {
     return;
   }
@@ -219,23 +219,22 @@ void cmFindCommon::RerootPaths(std::vector<std::string>& paths)
   // Construct the list of path roots with no trailing slashes.
   std::vector<std::string> roots;
   if (rootPath) {
-    cmExpandList(rootPath, roots);
+    cmExpandList(*rootPath, roots);
   }
   if (sysrootCompile) {
-    roots.emplace_back(sysrootCompile);
+    roots.emplace_back(*sysrootCompile);
   }
   if (sysrootLink) {
-    roots.emplace_back(sysrootLink);
+    roots.emplace_back(*sysrootLink);
   }
   if (sysroot) {
-    roots.emplace_back(sysroot);
+    roots.emplace_back(*sysroot);
   }
   for (std::string& r : roots) {
     cmSystemTools::ConvertToUnixSlashes(r);
   }
 
-  const char* stagePrefix =
-    this->Makefile->GetDefinition("CMAKE_STAGING_PREFIX");
+  cmProp stagePrefix = this->Makefile->GetDefinition("CMAKE_STAGING_PREFIX");
 
   // Copy the original set of unrooted paths.
   std::vector<std::string> unrootedPaths = paths;
@@ -248,7 +247,7 @@ void cmFindCommon::RerootPaths(std::vector<std::string>& paths)
       // a user home directory or is empty.
       std::string rootedDir;
       if (cmSystemTools::IsSubDirectory(up, r) ||
-          (stagePrefix && cmSystemTools::IsSubDirectory(up, stagePrefix))) {
+          (stagePrefix && cmSystemTools::IsSubDirectory(up, *stagePrefix))) {
         rootedDir = up;
       } else if (!up.empty() && up[0] != '~') {
         // Start with the new root.
diff --git a/Source/cmFindCommon.h b/Source/cmFindCommon.h
index 916f3bc..f84242e 100644
--- a/Source/cmFindCommon.h
+++ b/Source/cmFindCommon.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFindCommon_h
-#define cmFindCommon_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -143,5 +142,3 @@ protected:
   cmMakefile* Makefile;
   cmExecutionStatus& Status;
 };
-
-#endif
diff --git a/Source/cmFindFileCommand.h b/Source/cmFindFileCommand.h
index 7dc6e55..368a7c9 100644
--- a/Source/cmFindFileCommand.h
+++ b/Source/cmFindFileCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFindFileCommand_h
-#define cmFindFileCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -28,5 +27,3 @@ public:
 
 bool cmFindFile(std::vector<std::string> const& args,
                 cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmFindLibraryCommand.cxx b/Source/cmFindLibraryCommand.cxx
index 3242b6d..b87dfe3 100644
--- a/Source/cmFindLibraryCommand.cxx
+++ b/Source/cmFindLibraryCommand.cxx
@@ -13,6 +13,7 @@
 #include "cmGlobalGenerator.h"
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
@@ -50,9 +51,9 @@ bool cmFindLibraryCommand::InitialPass(std::vector<std::string> const& argsIn)
 
   // add custom lib<qual> paths instead of using fixed lib32, lib64 or
   // libx32
-  if (const char* customLib = this->Makefile->GetDefinition(
+  if (cmProp customLib = this->Makefile->GetDefinition(
         "CMAKE_FIND_LIBRARY_CUSTOM_LIB_SUFFIX")) {
-    this->AddArchitecturePaths(customLib);
+    this->AddArchitecturePaths(customLib->c_str());
   }
   // add special 32 bit paths if this is a 32 bit compile.
   else if (this->Makefile->PlatformIs32Bit() &&
diff --git a/Source/cmFindLibraryCommand.h b/Source/cmFindLibraryCommand.h
index b2f71b3..f3874ff 100644
--- a/Source/cmFindLibraryCommand.h
+++ b/Source/cmFindLibraryCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFindLibraryCommand_h
-#define cmFindLibraryCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -44,5 +43,3 @@ private:
 
 bool cmFindLibrary(std::vector<std::string> const& args,
                    cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmFindPackageCommand.cxx b/Source/cmFindPackageCommand.cxx
index 8d5b177..c462651 100644
--- a/Source/cmFindPackageCommand.cxx
+++ b/Source/cmFindPackageCommand.cxx
@@ -154,10 +154,10 @@ bool cmFindPackageCommand::InitialPass(std::vector<std::string> const& args)
   }
 
   // Lookup required version of CMake.
-  if (const char* rv =
+  if (cmProp rv =
         this->Makefile->GetDefinition("CMAKE_MINIMUM_REQUIRED_VERSION")) {
     unsigned int v[3] = { 0, 0, 0 };
-    sscanf(rv, "%u.%u.%u", &v[0], &v[1], &v[2]);
+    sscanf(rv->c_str(), "%u.%u.%u", &v[0], &v[1], &v[2]);
     this->RequiredCMakeVersion = CMake_VERSION_ENCODE(v[0], v[1], v[2]);
   }
 
@@ -165,9 +165,9 @@ bool cmFindPackageCommand::InitialPass(std::vector<std::string> const& args)
   this->DebugBuffer.clear();
 
   // Lookup target architecture, if any.
-  if (const char* arch =
+  if (cmProp arch =
         this->Makefile->GetDefinition("CMAKE_LIBRARY_ARCHITECTURE")) {
-    this->LibraryArchitecture = arch;
+    this->LibraryArchitecture = *arch;
   }
 
   // Lookup whether lib32 paths should be used.
@@ -194,9 +194,9 @@ bool cmFindPackageCommand::InitialPass(std::vector<std::string> const& args)
   // Check if User Package Registry should be disabled
   // The `CMAKE_FIND_USE_PACKAGE_REGISTRY` has
   // priority over the deprecated CMAKE_FIND_PACKAGE_NO_PACKAGE_REGISTRY
-  if (const char* def =
+  if (cmProp def =
         this->Makefile->GetDefinition("CMAKE_FIND_USE_PACKAGE_REGISTRY")) {
-    this->NoUserRegistry = !cmIsOn(def);
+    this->NoUserRegistry = !cmIsOn(*def);
   } else if (this->Makefile->IsOn("CMAKE_FIND_PACKAGE_NO_PACKAGE_REGISTRY")) {
     this->NoUserRegistry = true;
   }
@@ -204,9 +204,9 @@ bool cmFindPackageCommand::InitialPass(std::vector<std::string> const& args)
   // Check if System Package Registry should be disabled
   // The `CMAKE_FIND_USE_SYSTEM_PACKAGE_REGISTRY` has
   // priority over the deprecated CMAKE_FIND_PACKAGE_NO_SYSTEM_PACKAGE_REGISTRY
-  if (const char* def = this->Makefile->GetDefinition(
+  if (cmProp def = this->Makefile->GetDefinition(
         "CMAKE_FIND_USE_SYSTEM_PACKAGE_REGISTRY")) {
-    this->NoSystemRegistry = !cmIsOn(def);
+    this->NoSystemRegistry = !cmIsOn(*def);
   } else if (this->Makefile->IsOn(
                "CMAKE_FIND_PACKAGE_NO_SYSTEM_PACKAGE_REGISTRY")) {
     this->NoSystemRegistry = true;
@@ -218,20 +218,20 @@ bool cmFindPackageCommand::InitialPass(std::vector<std::string> const& args)
   }
 
   // Check if Sorting should be enabled
-  if (const char* so =
+  if (cmProp so =
         this->Makefile->GetDefinition("CMAKE_FIND_PACKAGE_SORT_ORDER")) {
 
-    if (strcmp(so, "NAME") == 0) {
+    if (*so == "NAME") {
       this->SortOrder = Name_order;
-    } else if (strcmp(so, "NATURAL") == 0) {
+    } else if (*so == "NATURAL") {
       this->SortOrder = Natural;
     } else {
       this->SortOrder = None;
     }
   }
-  if (const char* sd =
+  if (cmProp sd =
         this->Makefile->GetDefinition("CMAKE_FIND_PACKAGE_SORT_DIRECTION")) {
-    this->SortDirection = strcmp(sd, "ASC") == 0 ? Asc : Dec;
+    this->SortDirection = (*sd == "ASC") ? Asc : Dec;
   }
 
   // Find what search path locations have been enabled/disable
@@ -675,9 +675,9 @@ void cmFindPackageCommand::SetModuleVariables(const std::string& components)
 void cmFindPackageCommand::AddFindDefinition(const std::string& var,
                                              const char* val)
 {
-  if (const char* old = this->Makefile->GetDefinition(var)) {
+  if (cmProp old = this->Makefile->GetDefinition(var)) {
     this->OriginalDefs[var].exists = true;
-    this->OriginalDefs[var].value = old;
+    this->OriginalDefs[var].value = *old;
   } else {
     this->OriginalDefs[var].exists = false;
   }
@@ -759,14 +759,14 @@ bool cmFindPackageCommand::HandlePackageMode(
   this->ConsideredConfigs.clear();
 
   // Try to find the config file.
-  const char* def = this->Makefile->GetDefinition(this->Variable);
+  cmProp def = this->Makefile->GetDefinition(this->Variable);
 
   // Try to load the config file if the directory is known
   bool fileFound = false;
   if (this->UseConfigFiles) {
     if (!cmIsOff(def)) {
       // Get the directory from the variable value.
-      std::string dir = def;
+      std::string dir = *def;
       cmSystemTools::ConvertToUnixSlashes(dir);
 
       // Treat relative paths with respect to the current source dir.
@@ -1121,7 +1121,7 @@ void cmFindPackageCommand::AppendToFoundProperty(bool found)
   std::vector<std::string> foundContents;
   cmProp foundProp =
     this->Makefile->GetState()->GetGlobalProperty("PACKAGES_FOUND");
-  if (foundProp && !foundProp->empty()) {
+  if (cmNonempty(foundProp)) {
     cmExpandList(*foundProp, foundContents, false);
     auto nameIt =
       std::find(foundContents.begin(), foundContents.end(), this->Name);
@@ -1133,7 +1133,7 @@ void cmFindPackageCommand::AppendToFoundProperty(bool found)
   std::vector<std::string> notFoundContents;
   cmProp notFoundProp =
     this->Makefile->GetState()->GetGlobalProperty("PACKAGES_NOT_FOUND");
-  if (notFoundProp && !notFoundProp->empty()) {
+  if (cmNonempty(notFoundProp)) {
     cmExpandList(*notFoundProp, notFoundContents, false);
     auto nameIt =
       std::find(notFoundContents.begin(), notFoundContents.end(), this->Name);
@@ -1166,9 +1166,9 @@ void cmFindPackageCommand::AppendSuccessInformation()
   std::string found = cmStrCat(this->Name, "_FOUND");
   std::string upperFound = cmSystemTools::UpperCase(found);
 
-  const char* upperResult = this->Makefile->GetDefinition(upperFound);
-  const char* result = this->Makefile->GetDefinition(found);
-  bool packageFound = ((cmIsOn(result)) || (cmIsOn(upperResult)));
+  bool upperResult = this->Makefile->IsOn(upperFound);
+  bool result = this->Makefile->IsOn(found);
+  bool packageFound = (result || upperResult);
 
   this->AppendToFoundProperty(packageFound);
 
diff --git a/Source/cmFindPackageCommand.h b/Source/cmFindPackageCommand.h
index 7058a54..eacd1ce 100644
--- a/Source/cmFindPackageCommand.h
+++ b/Source/cmFindPackageCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFindPackageCommand_h
-#define cmFindPackageCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -233,5 +232,3 @@ struct hash<cmFindPackageCommand::ConfigFileInfo>
 
 bool cmFindPackage(std::vector<std::string> const& args,
                    cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmFindPathCommand.h b/Source/cmFindPathCommand.h
index 18bfb7d..b9fe673 100644
--- a/Source/cmFindPathCommand.h
+++ b/Source/cmFindPathCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFindPathCommand_h
-#define cmFindPathCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -38,5 +37,3 @@ private:
 
 bool cmFindPath(std::vector<std::string> const& args,
                 cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmFindProgramCommand.cxx b/Source/cmFindProgramCommand.cxx
index 4b88bea..77728ec 100644
--- a/Source/cmFindProgramCommand.cxx
+++ b/Source/cmFindProgramCommand.cxx
@@ -4,6 +4,7 @@
 
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmPolicies.h"
 #include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -19,6 +20,7 @@ struct cmFindProgramHelper
   cmFindProgramHelper(cmMakefile* makefile, cmFindBase const* base)
     : DebugSearches("find_program", base)
     , Makefile(makefile)
+    , PolicyCMP0109(makefile->GetPolicyStatus(cmPolicies::CMP0109))
   {
 #if defined(_WIN32) || defined(__CYGWIN__) || defined(__MINGW32__)
     // Consider platform-specific extensions.
@@ -48,6 +50,8 @@ struct cmFindProgramHelper
   cmFindBaseDebugState DebugSearches;
   cmMakefile* Makefile;
 
+  cmPolicies::PolicyStatus PolicyCMP0109;
+
   void AddName(std::string const& name) { this->Names.push_back(name); }
   void SetName(std::string const& name)
   {
@@ -85,7 +89,7 @@ struct cmFindProgramHelper
       this->TestNameExt = cmStrCat(name, ext);
       this->TestPath =
         cmSystemTools::CollapseFullPath(this->TestNameExt, path);
-      bool exists = cmSystemTools::FileExists(this->TestPath, true);
+      bool exists = this->FileIsExecutable(this->TestPath);
       exists ? this->DebugSearches.FoundAt(this->TestPath)
              : this->DebugSearches.FailedAt(this->TestPath);
       if (exists) {
@@ -95,6 +99,48 @@ struct cmFindProgramHelper
     }
     return false;
   }
+  bool FileIsExecutable(std::string const& file) const
+  {
+    switch (this->PolicyCMP0109) {
+      case cmPolicies::OLD:
+        return cmSystemTools::FileExists(file, true);
+      case cmPolicies::NEW:
+      case cmPolicies::REQUIRED_ALWAYS:
+      case cmPolicies::REQUIRED_IF_USED:
+        return cmSystemTools::FileIsExecutable(file);
+      default:
+        break;
+    }
+    bool const isExeOld = cmSystemTools::FileExists(file, true);
+    bool const isExeNew = cmSystemTools::FileIsExecutable(file);
+    if (isExeNew == isExeOld) {
+      return isExeNew;
+    }
+    if (isExeNew) {
+      this->Makefile->IssueMessage(
+        MessageType::AUTHOR_WARNING,
+        cmStrCat(cmPolicies::GetPolicyWarning(cmPolicies::CMP0109),
+                 "\n"
+                 "The file\n"
+                 "  ",
+                 file,
+                 "\n"
+                 "is executable but not readable.  "
+                 "CMake is ignoring it for compatibility."));
+    } else {
+      this->Makefile->IssueMessage(
+        MessageType::AUTHOR_WARNING,
+        cmStrCat(cmPolicies::GetPolicyWarning(cmPolicies::CMP0109),
+                 "\n"
+                 "The file\n"
+                 "  ",
+                 file,
+                 "\n"
+                 "is readable but not executable.  "
+                 "CMake is using it for compatibility."));
+    }
+    return isExeOld;
+  }
 };
 
 cmFindProgramCommand::cmFindProgramCommand(cmExecutionStatus& status)
@@ -266,14 +312,13 @@ std::string cmFindProgramCommand::GetBundleExecutable(
 
   if (executableURL != nullptr) {
     const int MAX_OSX_PATH_SIZE = 1024;
-    char buffer[MAX_OSX_PATH_SIZE];
+    UInt8 buffer[MAX_OSX_PATH_SIZE];
 
-    // Convert the CFString to a C string
-    CFStringGetCString(CFURLGetString(executableURL), buffer,
-                       MAX_OSX_PATH_SIZE, kCFStringEncodingUTF8);
-
-    // And finally to a c++ string
-    executable = bundlePath + "/Contents/MacOS/" + std::string(buffer);
+    if (CFURLGetFileSystemRepresentation(executableURL, false, buffer,
+                                         MAX_OSX_PATH_SIZE)) {
+      executable = bundlePath + "/Contents/MacOS/" +
+        std::string(reinterpret_cast<char*>(buffer));
+    }
     // Only release CFURLRef if it's not null
     CFRelease(executableURL);
   }
diff --git a/Source/cmFindProgramCommand.h b/Source/cmFindProgramCommand.h
index 043b43c..161a680 100644
--- a/Source/cmFindProgramCommand.h
+++ b/Source/cmFindProgramCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFindProgramCommand_h
-#define cmFindProgramCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -38,5 +37,3 @@ private:
 
 bool cmFindProgram(std::vector<std::string> const& args,
                    cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmForEachCommand.cxx b/Source/cmForEachCommand.cxx
index 3b82e0a..12fb55a 100644
--- a/Source/cmForEachCommand.cxx
+++ b/Source/cmForEachCommand.cxx
@@ -25,6 +25,7 @@
 #include "cmListFileCache.h"
 #include "cmMakefile.h"
 #include "cmMessageType.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -113,8 +114,8 @@ bool cmForEachFunctionBlocker::ReplayItems(
   // At end of for each execute recorded commands
   // store the old value
   std::string oldDef;
-  if (auto d = mf.GetDefinition(this->Args.front())) {
-    oldDef = d;
+  if (cmProp d = mf.GetDefinition(this->Args.front())) {
+    oldDef = *d;
   }
 
   auto restore = false;
@@ -186,8 +187,8 @@ bool cmForEachFunctionBlocker::ReplayZipLists(
   // Store old values for iteration variables
   std::map<std::string, std::string> oldDefs;
   for (auto i = 0u; i < values.size(); ++i) {
-    if (auto d = mf.GetDefinition(iterationVars[i])) {
-      oldDefs.emplace(iterationVars[i], d);
+    if (cmProp d = mf.GetDefinition(iterationVars[i])) {
+      oldDefs.emplace(iterationVars[i], *d);
     }
   }
 
diff --git a/Source/cmForEachCommand.h b/Source/cmForEachCommand.h
index 1feb965..6476fea 100644
--- a/Source/cmForEachCommand.h
+++ b/Source/cmForEachCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmForEachCommand_h
-#define cmForEachCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -13,4 +12,3 @@ class cmExecutionStatus;
 /// Starts foreach() ... endforeach() block
 bool cmForEachCommand(std::vector<std::string> const& args,
                       cmExecutionStatus& status);
-#endif
diff --git a/Source/cmFortranParser.h b/Source/cmFortranParser.h
index 6f97b42..1b14d17 100644
--- a/Source/cmFortranParser.h
+++ b/Source/cmFortranParser.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFortranParser_h
-#define cmFortranParser_h
+#pragma once
 
 #if !defined(cmFortranLexer_cxx) && !defined(cmFortranParser_cxx)
 #  include "cmConfigure.h" // IWYU pragma: keep
@@ -181,5 +180,3 @@ struct cmFortranParser_s
   cmFortranSourceInfo& Info;
 };
 #endif
-
-#endif
diff --git a/Source/cmFunctionBlocker.h b/Source/cmFunctionBlocker.h
index 59bb892..b4b493b 100644
--- a/Source/cmFunctionBlocker.h
+++ b/Source/cmFunctionBlocker.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFunctionBlocker_h
-#define cmFunctionBlocker_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -50,5 +49,3 @@ private:
   std::vector<cmListFileFunction> Functions;
   unsigned int ScopeDepth = 1;
 };
-
-#endif
diff --git a/Source/cmFunctionCommand.h b/Source/cmFunctionCommand.h
index d6b549c..07ff4f7 100644
--- a/Source/cmFunctionCommand.h
+++ b/Source/cmFunctionCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmFunctionCommand_h
-#define cmFunctionCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -13,5 +12,3 @@ class cmExecutionStatus;
 /// Starts function() ... endfunction() block
 bool cmFunctionCommand(std::vector<std::string> const& args,
                        cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGccDepfileLexerHelper.h b/Source/cmGccDepfileLexerHelper.h
index e6b2fcf..07ca61d 100644
--- a/Source/cmGccDepfileLexerHelper.h
+++ b/Source/cmGccDepfileLexerHelper.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGccDepfileLexerHelper_h
-#define cmGccDepfileLexerHelper_h
+#pragma once
 
 #include <utility>
 
@@ -36,5 +35,3 @@ private:
 };
 
 #define YY_EXTRA_TYPE cmGccDepfileLexerHelper*
-
-#endif
diff --git a/Source/cmGccDepfileReader.h b/Source/cmGccDepfileReader.h
index 9313010..395dd77 100644
--- a/Source/cmGccDepfileReader.h
+++ b/Source/cmGccDepfileReader.h
@@ -1,10 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGccDepfileReader_h
-#define cmGccDepfileReader_h
+#pragma once
 
 #include "cmGccDepfileReaderTypes.h"
 
 cmGccDepfileContent cmReadGccDepfile(const char* filePath);
-
-#endif
diff --git a/Source/cmGccDepfileReaderTypes.h b/Source/cmGccDepfileReaderTypes.h
index 8b15c73..246e355 100644
--- a/Source/cmGccDepfileReaderTypes.h
+++ b/Source/cmGccDepfileReaderTypes.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGccDepfileReaderTypes_h
-#define cmGccDepfileReaderTypes_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -13,5 +12,3 @@ struct cmGccStyleDependency
 };
 
 using cmGccDepfileContent = std::vector<cmGccStyleDependency>;
-
-#endif
diff --git a/Source/cmGeneratedFileStream.cxx b/Source/cmGeneratedFileStream.cxx
index 9cee0e6..2768547 100644
--- a/Source/cmGeneratedFileStream.cxx
+++ b/Source/cmGeneratedFileStream.cxx
@@ -14,10 +14,11 @@
 #endif
 
 cmGeneratedFileStream::cmGeneratedFileStream(Encoding encoding)
+  : OriginalLocale(getloc())
 {
 #ifndef CMAKE_BOOTSTRAP
   if (encoding != codecvt::None) {
-    imbue(std::locale(getloc(), new codecvt(encoding)));
+    imbue(std::locale(OriginalLocale, new codecvt(encoding)));
   }
 #else
   static_cast<void>(encoding);
@@ -122,10 +123,17 @@ void cmGeneratedFileStreamBase::Open(std::string const& name)
   // Create the name of the temporary file.
   this->TempName = name;
 #if defined(__VMS)
-  this->TempName += "_tmp";
+  this->TempName += "_";
 #else
-  this->TempName += ".tmp";
+  this->TempName += ".";
 #endif
+  if (!this->TempExt.empty()) {
+    this->TempName += this->TempExt;
+  } else {
+    char buf[64];
+    sprintf(buf, "tmp%05x", cmSystemTools::RandomSeed() & 0xFFFFF);
+    this->TempName += buf;
+  }
 
   // Make sure the temporary file that will be used is not present.
   cmSystemTools::RemoveFile(this->TempName);
@@ -216,3 +224,19 @@ void cmGeneratedFileStream::SetName(const std::string& fname)
 {
   this->Name = fname;
 }
+
+void cmGeneratedFileStream::SetTempExt(std::string const& ext)
+{
+  this->TempExt = ext;
+}
+
+void cmGeneratedFileStream::WriteRaw(std::string const& data)
+{
+#ifndef CMAKE_BOOTSTRAP
+  std::locale activeLocale = this->imbue(this->OriginalLocale);
+  this->write(data.data(), data.size());
+  this->imbue(activeLocale);
+#else
+  this->write(data.data(), data.size());
+#endif
+}
diff --git a/Source/cmGeneratedFileStream.h b/Source/cmGeneratedFileStream.h
index a9088ac..bb7e3bf 100644
--- a/Source/cmGeneratedFileStream.h
+++ b/Source/cmGeneratedFileStream.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratedFileStream_h
-#define cmGeneratedFileStream_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -43,6 +42,9 @@ protected:
   // The name of the final destination file for the output.
   std::string Name;
 
+  // The extension of the temporary file.
+  std::string TempExt;
+
   // The name of the temporary file.
   std::string TempName;
 
@@ -138,6 +140,20 @@ public:
    * the output file to be changed during the use of cmGeneratedFileStream.
    */
   void SetName(const std::string& fname);
-};
 
-#endif
+  /**
+   * Set set a custom temporary file extension used with 'Open'.
+   * This does not work if the file was opened by the constructor.
+   */
+  void SetTempExt(std::string const& ext);
+
+  /**
+   * Writes the given string directly to the file without changing the
+   * encoding.
+   */
+  void WriteRaw(std::string const& data);
+
+private:
+  // The original locale of the stream (performs no encoding conversion).
+  std::locale OriginalLocale;
+};
diff --git a/Source/cmGeneratorExpression.cxx b/Source/cmGeneratorExpression.cxx
index 6e293d5..840f511 100644
--- a/Source/cmGeneratorExpression.cxx
+++ b/Source/cmGeneratorExpression.cxx
@@ -406,9 +406,3 @@ const std::string& cmGeneratorExpressionInterpreter::Evaluate(
     this->LocalGenerator, this->Config, this->HeadTarget, &dagChecker, nullptr,
     this->Language);
 }
-
-const std::string& cmGeneratorExpressionInterpreter::Evaluate(
-  const char* expression, const std::string& property)
-{
-  return this->Evaluate(std::string(expression ? expression : ""), property);
-}
diff --git a/Source/cmGeneratorExpression.h b/Source/cmGeneratorExpression.h
index 75bba02..03be782 100644
--- a/Source/cmGeneratorExpression.h
+++ b/Source/cmGeneratorExpression.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpression_h
-#define cmGeneratorExpression_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -199,8 +198,6 @@ public:
 
   const std::string& Evaluate(std::string expression,
                               const std::string& property);
-  const std::string& Evaluate(const char* expression,
-                              const std::string& property);
 
 protected:
   cmGeneratorExpression GeneratorExpression;
@@ -210,5 +207,3 @@ protected:
   cmGeneratorTarget const* HeadTarget = nullptr;
   std::string Language;
 };
-
-#endif
diff --git a/Source/cmGeneratorExpressionContext.h b/Source/cmGeneratorExpressionContext.h
index bceff12..22e7463 100644
--- a/Source/cmGeneratorExpressionContext.h
+++ b/Source/cmGeneratorExpressionContext.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpressionContext_h
-#define cmGeneratorExpressionContext_h
+#pragma once
 
 #include <map>
 #include <set>
@@ -43,5 +42,3 @@ struct cmGeneratorExpressionContext
   bool HadLinkLanguageSensitiveCondition;
   bool EvaluateForBuildsystem;
 };
-
-#endif
diff --git a/Source/cmGeneratorExpressionDAGChecker.cxx b/Source/cmGeneratorExpressionDAGChecker.cxx
index 4f379cd..e223f15 100644
--- a/Source/cmGeneratorExpressionDAGChecker.cxx
+++ b/Source/cmGeneratorExpressionDAGChecker.cxx
@@ -154,6 +154,14 @@ bool cmGeneratorExpressionDAGChecker::EvaluatingPICExpression() const
   return this->Top()->Property == "INTERFACE_POSITION_INDEPENDENT_CODE";
 }
 
+bool cmGeneratorExpressionDAGChecker::EvaluatingCompileExpression() const
+{
+  cm::string_view property(this->Top()->Property);
+
+  return property == "INCLUDE_DIRECTORIES"_s ||
+    property == "COMPILE_DEFINITIONS"_s || property == "COMPILE_OPTIONS"_s;
+}
+
 bool cmGeneratorExpressionDAGChecker::EvaluatingLinkExpression() const
 {
   cm::string_view property(this->Top()->Property);
diff --git a/Source/cmGeneratorExpressionDAGChecker.h b/Source/cmGeneratorExpressionDAGChecker.h
index c2c5b6b..53225cd 100644
--- a/Source/cmGeneratorExpressionDAGChecker.h
+++ b/Source/cmGeneratorExpressionDAGChecker.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpressionDAGChecker_h
-#define cmGeneratorExpressionDAGChecker_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -68,6 +67,7 @@ struct cmGeneratorExpressionDAGChecker
 
   bool EvaluatingGenexExpression() const;
   bool EvaluatingPICExpression() const;
+  bool EvaluatingCompileExpression() const;
   bool EvaluatingLinkExpression() const;
   bool EvaluatingLinkOptionsExpression() const;
 
@@ -99,5 +99,3 @@ private:
   Result CheckResult;
   bool TransitivePropertiesOnly;
 };
-
-#endif
diff --git a/Source/cmGeneratorExpressionEvaluationFile.cxx b/Source/cmGeneratorExpressionEvaluationFile.cxx
index 9e8707d..9e5023d 100644
--- a/Source/cmGeneratorExpressionEvaluationFile.cxx
+++ b/Source/cmGeneratorExpressionEvaluationFile.cxx
@@ -19,11 +19,12 @@
 #include "cmSystemTools.h"
 
 cmGeneratorExpressionEvaluationFile::cmGeneratorExpressionEvaluationFile(
-  std::string input,
+  std::string input, std::string target,
   std::unique_ptr<cmCompiledGeneratorExpression> outputFileExpr,
   std::unique_ptr<cmCompiledGeneratorExpression> condition,
   bool inputIsContent, cmPolicies::PolicyStatus policyStatusCMP0070)
   : Input(std::move(input))
+  , Target(std::move(target))
   , OutputFileExpr(std::move(outputFileExpr))
   , Condition(std::move(condition))
   , InputIsContent(inputIsContent)
@@ -37,9 +38,10 @@ void cmGeneratorExpressionEvaluationFile::Generate(
   std::map<std::string, std::string>& outputFiles, mode_t perm)
 {
   std::string rawCondition = this->Condition->GetInput();
+  cmGeneratorTarget* target = lg->FindGeneratorTargetToUse(Target);
   if (!rawCondition.empty()) {
     std::string condResult =
-      this->Condition->Evaluate(lg, config, nullptr, nullptr, nullptr, lang);
+      this->Condition->Evaluate(lg, config, target, nullptr, nullptr, lang);
     if (condResult == "0") {
       return;
     }
@@ -54,16 +56,10 @@ void cmGeneratorExpressionEvaluationFile::Generate(
     }
   }
 
-  std::string outputFileName = this->OutputFileExpr->Evaluate(
-    lg, config, nullptr, nullptr, nullptr, lang);
+  const std::string outputFileName =
+    this->GetOutputFileName(lg, target, config, lang);
   const std::string& outputContent =
-    inputExpression->Evaluate(lg, config, nullptr, nullptr, nullptr, lang);
-
-  if (cmSystemTools::FileIsFullPath(outputFileName)) {
-    outputFileName = cmSystemTools::CollapseFullPath(outputFileName);
-  } else {
-    outputFileName = this->FixRelativePath(outputFileName, PathForOutput, lg);
-  }
+    inputExpression->Evaluate(lg, config, target, nullptr, nullptr, lang);
 
   auto it = outputFiles.find(outputFileName);
 
@@ -98,11 +94,11 @@ void cmGeneratorExpressionEvaluationFile::CreateOutputFile(
 {
   std::vector<std::string> enabledLanguages;
   cmGlobalGenerator* gg = lg->GetGlobalGenerator();
+  cmGeneratorTarget* target = lg->FindGeneratorTargetToUse(Target);
   gg->GetEnabledLanguages(enabledLanguages);
 
   for (std::string const& le : enabledLanguages) {
-    std::string name = this->OutputFileExpr->Evaluate(lg, config, nullptr,
-                                                      nullptr, nullptr, le);
+    std::string const name = this->GetOutputFileName(lg, target, config, le);
     cmSourceFile* sf = lg->GetMakefile()->GetOrCreateSource(
       name, false, cmSourceFileLocationKind::Known);
     // Tell TraceDependencies that the file is not expected to exist
@@ -125,12 +121,7 @@ void cmGeneratorExpressionEvaluationFile::Generate(cmLocalGenerator* lg)
   if (this->InputIsContent) {
     inputContent = this->Input;
   } else {
-    std::string inputFileName = this->Input;
-    if (cmSystemTools::FileIsFullPath(inputFileName)) {
-      inputFileName = cmSystemTools::CollapseFullPath(inputFileName);
-    } else {
-      inputFileName = this->FixRelativePath(inputFileName, PathForInput, lg);
-    }
+    const std::string inputFileName = this->GetInputFileName(lg);
     lg->GetMakefile()->AddCMakeDependFile(inputFileName);
     cmSystemTools::GetPermissions(inputFileName.c_str(), perm);
     cmsys::ifstream fin(inputFileName.c_str());
@@ -157,12 +148,8 @@ void cmGeneratorExpressionEvaluationFile::Generate(cmLocalGenerator* lg)
 
   std::map<std::string, std::string> outputFiles;
 
-  std::vector<std::string> allConfigs;
-  lg->GetMakefile()->GetConfigurations(allConfigs);
-
-  if (allConfigs.empty()) {
-    allConfigs.emplace_back();
-  }
+  std::vector<std::string> allConfigs =
+    lg->GetMakefile()->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
   std::vector<std::string> enabledLanguages;
   cmGlobalGenerator* gg = lg->GetGlobalGenerator();
@@ -178,6 +165,36 @@ void cmGeneratorExpressionEvaluationFile::Generate(cmLocalGenerator* lg)
   }
 }
 
+std::string cmGeneratorExpressionEvaluationFile::GetInputFileName(
+  cmLocalGenerator* lg)
+{
+  std::string inputFileName = this->Input;
+
+  if (cmSystemTools::FileIsFullPath(inputFileName)) {
+    inputFileName = cmSystemTools::CollapseFullPath(inputFileName);
+  } else {
+    inputFileName = this->FixRelativePath(inputFileName, PathForInput, lg);
+  }
+
+  return inputFileName;
+}
+
+std::string cmGeneratorExpressionEvaluationFile::GetOutputFileName(
+  cmLocalGenerator* lg, cmGeneratorTarget* target, const std::string& config,
+  const std::string& lang)
+{
+  std::string outputFileName =
+    this->OutputFileExpr->Evaluate(lg, config, target, nullptr, nullptr, lang);
+
+  if (cmSystemTools::FileIsFullPath(outputFileName)) {
+    outputFileName = cmSystemTools::CollapseFullPath(outputFileName);
+  } else {
+    outputFileName = this->FixRelativePath(outputFileName, PathForOutput, lg);
+  }
+
+  return outputFileName;
+}
+
 std::string cmGeneratorExpressionEvaluationFile::FixRelativePath(
   std::string const& relativePath, PathRole role, cmLocalGenerator* lg)
 {
diff --git a/Source/cmGeneratorExpressionEvaluationFile.h b/Source/cmGeneratorExpressionEvaluationFile.h
index c3bc4c8..2cd35ae 100644
--- a/Source/cmGeneratorExpressionEvaluationFile.h
+++ b/Source/cmGeneratorExpressionEvaluationFile.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpressionEvaluationFile_h
-#define cmGeneratorExpressionEvaluationFile_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -15,13 +14,14 @@
 #include "cmGeneratorExpression.h"
 #include "cmPolicies.h"
 
+class cmGeneratorTarget;
 class cmLocalGenerator;
 
 class cmGeneratorExpressionEvaluationFile
 {
 public:
   cmGeneratorExpressionEvaluationFile(
-    std::string input,
+    std::string input, std::string target,
     std::unique_ptr<cmCompiledGeneratorExpression> outputFileExpr,
     std::unique_ptr<cmCompiledGeneratorExpression> condition,
     bool inputIsContent, cmPolicies::PolicyStatus policyStatusCMP0070);
@@ -38,6 +38,11 @@ private:
                 cmCompiledGeneratorExpression* inputExpression,
                 std::map<std::string, std::string>& outputFiles, mode_t perm);
 
+  std::string GetInputFileName(cmLocalGenerator* lg);
+  std::string GetOutputFileName(cmLocalGenerator* lg,
+                                cmGeneratorTarget* target,
+                                const std::string& config,
+                                const std::string& lang);
   enum PathRole
   {
     PathForInput,
@@ -48,11 +53,10 @@ private:
 
 private:
   const std::string Input;
+  const std::string Target;
   const std::unique_ptr<cmCompiledGeneratorExpression> OutputFileExpr;
   const std::unique_ptr<cmCompiledGeneratorExpression> Condition;
   std::vector<std::string> Files;
   const bool InputIsContent;
   cmPolicies::PolicyStatus PolicyStatusCMP0070;
 };
-
-#endif
diff --git a/Source/cmGeneratorExpressionEvaluator.h b/Source/cmGeneratorExpressionEvaluator.h
index 10496fd..3e7737e 100644
--- a/Source/cmGeneratorExpressionEvaluator.h
+++ b/Source/cmGeneratorExpressionEvaluator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpressionEvaluator_h
-#define cmGeneratorExpressionEvaluator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -115,5 +114,3 @@ private:
   const char* StartContent;
   size_t ContentLength;
 };
-
-#endif
diff --git a/Source/cmGeneratorExpressionLexer.h b/Source/cmGeneratorExpressionLexer.h
index 9e01948..a4321d1 100644
--- a/Source/cmGeneratorExpressionLexer.h
+++ b/Source/cmGeneratorExpressionLexer.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpressionLexer_h
-#define cmGeneratorExpressionLexer_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -49,5 +48,3 @@ private:
   bool SawBeginExpression = false;
   bool SawGeneratorExpression = false;
 };
-
-#endif
diff --git a/Source/cmGeneratorExpressionNode.cxx b/Source/cmGeneratorExpressionNode.cxx
index e4fb67e..d3308e2 100644
--- a/Source/cmGeneratorExpressionNode.cxx
+++ b/Source/cmGeneratorExpressionNode.cxx
@@ -37,6 +37,7 @@
 #include "cmPolicies.h"
 #include "cmProperty.h"
 #include "cmRange.h"
+#include "cmStandardLevelResolver.h"
 #include "cmState.h"
 #include "cmStateSnapshot.h"
 #include "cmStateTypes.h"
@@ -714,7 +715,8 @@ struct CompilerIdNode : public cmGeneratorExpressionNode
 
 static const CompilerIdNode cCompilerIdNode("C"), cxxCompilerIdNode("CXX"),
   cudaCompilerIdNode("CUDA"), objcCompilerIdNode("OBJC"),
-  objcxxCompilerIdNode("OBJCXX"), fortranCompilerIdNode("Fortran");
+  objcxxCompilerIdNode("OBJCXX"), fortranCompilerIdNode("Fortran"),
+  ispcCompilerIdNode("ISPC");
 
 struct CompilerVersionNode : public cmGeneratorExpressionNode
 {
@@ -779,7 +781,7 @@ struct CompilerVersionNode : public cmGeneratorExpressionNode
 static const CompilerVersionNode cCompilerVersionNode("C"),
   cxxCompilerVersionNode("CXX"), cudaCompilerVersionNode("CUDA"),
   objcCompilerVersionNode("OBJC"), objcxxCompilerVersionNode("OBJCXX"),
-  fortranCompilerVersionNode("Fortran");
+  fortranCompilerVersionNode("Fortran"), ispcCompilerVersionNode("ISPC");
 
 struct PlatformIdNode : public cmGeneratorExpressionNode
 {
@@ -881,7 +883,7 @@ static const struct ConfigurationTestNode : public cmGeneratorExpressionNode
 {
   ConfigurationTestNode() {} // NOLINT(modernize-use-equals-default)
 
-  int NumExpectedParameters() const override { return OneOrZeroParameters; }
+  int NumExpectedParameters() const override { return ZeroOrMoreParameters; }
 
   std::string Evaluate(
     const std::vector<std::string>& parameters,
@@ -899,13 +901,15 @@ static const struct ConfigurationTestNode : public cmGeneratorExpressionNode
       return std::string();
     }
     context->HadContextSensitiveCondition = true;
-    if (context->Config.empty()) {
-      return parameters.front().empty() ? "1" : "0";
-    }
-
-    if (cmsysString_strcasecmp(parameters.front().c_str(),
-                               context->Config.c_str()) == 0) {
-      return "1";
+    for (auto& param : parameters) {
+      if (context->Config.empty()) {
+        if (param.empty()) {
+          return "1";
+        }
+      } else if (cmsysString_strcasecmp(param.c_str(),
+                                        context->Config.c_str()) == 0) {
+        return "1";
+      }
     }
 
     if (context->CurrentTarget && context->CurrentTarget->IsImported()) {
@@ -922,10 +926,12 @@ static const struct ConfigurationTestNode : public cmGeneratorExpressionNode
           "MAP_IMPORTED_CONFIG_", cmSystemTools::UpperCase(context->Config));
         if (cmProp mapValue = context->CurrentTarget->GetProperty(mapProp)) {
           cmExpandList(cmSystemTools::UpperCase(*mapValue), mappedConfigs);
-          return cm::contains(mappedConfigs,
-                              cmSystemTools::UpperCase(parameters.front()))
-            ? "1"
-            : "0";
+
+          for (auto& param : parameters) {
+            if (cm::contains(mappedConfigs, cmSystemTools::UpperCase(param))) {
+              return "1";
+            }
+          }
         }
       }
     }
@@ -962,9 +968,10 @@ static const struct CompileLanguageNode : public cmGeneratorExpressionNode
     const std::vector<std::string>& parameters,
     cmGeneratorExpressionContext* context,
     const GeneratorExpressionContent* content,
-    cmGeneratorExpressionDAGChecker* /*dagChecker*/) const override
+    cmGeneratorExpressionDAGChecker* dagChecker) const override
   {
-    if (context->Language.empty()) {
+    if (context->Language.empty() &&
+        (!dagChecker || !dagChecker->EvaluatingCompileExpression())) {
       reportError(
         context, content->GetOriginalExpression(),
         "$<COMPILE_LANGUAGE:...> may only be used to specify include "
@@ -1009,7 +1016,9 @@ static const struct CompileLanguageAndIdNode : public cmGeneratorExpressionNode
     const GeneratorExpressionContent* content,
     cmGeneratorExpressionDAGChecker* dagChecker) const override
   {
-    if (!context->HeadTarget || context->Language.empty()) {
+    if (!context->HeadTarget ||
+        (context->Language.empty() &&
+         (!dagChecker || !dagChecker->EvaluatingCompileExpression()))) {
       // reportError(context, content->GetOriginalExpression(), "");
       reportError(
         context, content->GetOriginalExpression(),
@@ -1468,8 +1477,9 @@ static const struct TargetPropertyNode : public cmGeneratorExpressionNode
     }
 
     if (isInterfaceProperty) {
-      return target->EvaluateInterfaceProperty(propertyName, context,
-                                               dagCheckerParent);
+      return cmGeneratorExpression::StripEmptyListElements(
+        target->EvaluateInterfaceProperty(propertyName, context,
+                                          dagCheckerParent));
     }
 
     cmGeneratorExpressionDAGChecker dagChecker(
@@ -1555,8 +1565,9 @@ static const struct TargetPropertyNode : public cmGeneratorExpressionNode
     }
 
     if (!interfacePropertyName.empty()) {
-      result = this->EvaluateDependentExpression(result, context->LG, context,
-                                                 target, &dagChecker, target);
+      result = cmGeneratorExpression::StripEmptyListElements(
+        this->EvaluateDependentExpression(result, context->LG, context, target,
+                                          &dagChecker, target));
       std::string linkedTargetsContent = getLinkedTargetsContent(
         target, interfacePropertyName, context, &dagChecker);
       if (!linkedTargetsContent.empty()) {
@@ -1703,12 +1714,12 @@ static const struct CompileFeaturesNode : public cmGeneratorExpressionNode
     static LangMap availableFeatures;
 
     LangMap testedFeatures;
-
+    cmStandardLevelResolver standardResolver(context->LG->GetMakefile());
     for (std::string const& p : parameters) {
       std::string error;
       std::string lang;
-      if (!context->LG->GetMakefile()->CompileFeatureKnown(
-            context->HeadTarget->Target, p, lang, &error)) {
+      if (!standardResolver.CompileFeatureKnown(
+            context->HeadTarget->Target->GetName(), p, lang, &error)) {
         reportError(context, content->GetOriginalExpression(), error);
         return std::string();
       }
@@ -1716,7 +1727,7 @@ static const struct CompileFeaturesNode : public cmGeneratorExpressionNode
 
       if (availableFeatures.find(lang) == availableFeatures.end()) {
         const char* featuresKnown =
-          context->LG->GetMakefile()->CompileFeaturesAvailable(lang, &error);
+          standardResolver.CompileFeaturesAvailable(lang, &error);
         if (!featuresKnown) {
           reportError(context, content->GetOriginalExpression(), error);
           return std::string();
@@ -1730,7 +1741,7 @@ static const struct CompileFeaturesNode : public cmGeneratorExpressionNode
     for (auto const& lit : testedFeatures) {
       std::vector<std::string> const& langAvailable =
         availableFeatures[lit.first];
-      cmProp standardDefault = context->LG->GetMakefile()->GetDef(
+      cmProp standardDefault = context->LG->GetMakefile()->GetDefinition(
         "CMAKE_" + lit.first + "_STANDARD_DEFAULT");
       for (std::string const& it : lit.second) {
         if (!cm::contains(langAvailable, it)) {
@@ -1741,10 +1752,10 @@ static const struct CompileFeaturesNode : public cmGeneratorExpressionNode
           // All features known for the language are always available.
           continue;
         }
-        if (!context->LG->GetMakefile()->HaveStandardAvailable(
-              target->Target, lit.first, it)) {
+        if (!standardResolver.HaveStandardAvailable(target, lit.first,
+                                                    context->Config, it)) {
           if (evalLL) {
-            cmProp l = target->GetProperty(lit.first + "_STANDARD");
+            cmProp l = target->GetLanguageStandard(lit.first, context->Config);
             if (!l) {
               l = standardDefault;
             }
@@ -1891,6 +1902,70 @@ class ArtifactSonameTag;
 class ArtifactBundleDirTag;
 class ArtifactBundleContentDirTag;
 
+template <typename ArtifactT, typename ComponentT>
+struct TargetFilesystemArtifactDependency
+{
+  static void AddDependency(cmGeneratorTarget* target,
+                            cmGeneratorExpressionContext* context)
+  {
+    context->DependTargets.insert(target);
+    context->AllTargets.insert(target);
+  }
+};
+
+struct TargetFilesystemArtifactDependencyCMP0112
+{
+  static void AddDependency(cmGeneratorTarget* target,
+                            cmGeneratorExpressionContext* context)
+  {
+    context->AllTargets.insert(target);
+    cmLocalGenerator* lg = context->LG;
+    switch (target->GetPolicyStatusCMP0112()) {
+      case cmPolicies::WARN:
+        if (lg->GetMakefile()->PolicyOptionalWarningEnabled(
+              "CMAKE_POLICY_WARNING_CMP0112")) {
+          std::string err =
+            cmStrCat(cmPolicies::GetPolicyWarning(cmPolicies::CMP0112),
+                     "\nDependency being added to target:\n  \"",
+                     target->GetName(), "\"\n");
+          lg->GetCMakeInstance()->IssueMessage(MessageType ::AUTHOR_WARNING,
+                                               err, context->Backtrace);
+        }
+        CM_FALLTHROUGH;
+      case cmPolicies::OLD:
+        context->DependTargets.insert(target);
+        break;
+      case cmPolicies::REQUIRED_IF_USED:
+      case cmPolicies::REQUIRED_ALWAYS:
+      case cmPolicies::NEW:
+        break;
+    }
+  }
+};
+
+template <typename ArtifactT>
+struct TargetFilesystemArtifactDependency<ArtifactT, ArtifactNameTag>
+  : TargetFilesystemArtifactDependencyCMP0112
+{
+};
+template <typename ArtifactT>
+struct TargetFilesystemArtifactDependency<ArtifactT, ArtifactDirTag>
+  : TargetFilesystemArtifactDependencyCMP0112
+{
+};
+template <>
+struct TargetFilesystemArtifactDependency<ArtifactBundleDirTag,
+                                          ArtifactPathTag>
+  : TargetFilesystemArtifactDependencyCMP0112
+{
+};
+template <>
+struct TargetFilesystemArtifactDependency<ArtifactBundleContentDirTag,
+                                          ArtifactPathTag>
+  : TargetFilesystemArtifactDependencyCMP0112
+{
+};
+
 template <typename ArtifactT>
 struct TargetFilesystemArtifactResultCreator
 {
@@ -2143,8 +2218,10 @@ struct TargetFilesystemArtifact : public TargetArtifactBase
     if (!target) {
       return std::string();
     }
-    context->DependTargets.insert(target);
-    context->AllTargets.insert(target);
+    // Not a dependent target if we are querying for ArtifactDirTag,
+    // ArtifactNameTag, ArtifactBundleDirTag, and ArtifactBundleContentDirTag
+    TargetFilesystemArtifactDependency<ArtifactT, ComponentT>::AddDependency(
+      target, context);
 
     std::string result =
       TargetFilesystemArtifactResultCreator<ArtifactT>::Create(target, context,
diff --git a/Source/cmGeneratorExpressionNode.h b/Source/cmGeneratorExpressionNode.h
index 13e8484..f068b02 100644
--- a/Source/cmGeneratorExpressionNode.h
+++ b/Source/cmGeneratorExpressionNode.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpressionNode_h
-#define cmGeneratorExpressionNode_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -52,5 +51,3 @@ struct cmGeneratorExpressionNode
 
 void reportError(cmGeneratorExpressionContext* context,
                  const std::string& expr, const std::string& result);
-
-#endif
diff --git a/Source/cmGeneratorExpressionParser.h b/Source/cmGeneratorExpressionParser.h
index 1ba1654..d49bf3e 100644
--- a/Source/cmGeneratorExpressionParser.h
+++ b/Source/cmGeneratorExpressionParser.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorExpressionParser_h
-#define cmGeneratorExpressionParser_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -30,5 +29,3 @@ private:
   const std::vector<cmGeneratorExpressionToken> Tokens;
   unsigned int NestingLevel;
 };
-
-#endif
diff --git a/Source/cmGeneratorTarget.cxx b/Source/cmGeneratorTarget.cxx
index ab6a26c..1bb069f 100644
--- a/Source/cmGeneratorTarget.cxx
+++ b/Source/cmGeneratorTarget.cxx
@@ -43,6 +43,7 @@
 #include "cmSourceFile.h"
 #include "cmSourceFileLocation.h"
 #include "cmSourceFileLocationKind.h"
+#include "cmStandardLevelResolver.h"
 #include "cmState.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -364,7 +365,7 @@ std::string cmGeneratorTarget::GetExportName() const
 {
   cmProp exportName = this->GetProperty("EXPORT_NAME");
 
-  if (exportName && !exportName->empty()) {
+  if (cmNonempty(exportName)) {
     if (!cmGeneratorExpression::IsValidTargetName(*exportName)) {
       std::ostringstream e;
       e << "EXPORT_NAME property \"" << *exportName << "\" for \""
@@ -379,11 +380,6 @@ std::string cmGeneratorTarget::GetExportName() const
 
 cmProp cmGeneratorTarget::GetProperty(const std::string& prop) const
 {
-  if (!cmTargetPropertyComputer::PassesWhitelist(
-        this->GetType(), prop, this->Makefile->GetMessenger(),
-        this->GetBacktrace())) {
-    return nullptr;
-  }
   if (cmProp result = cmTargetPropertyComputer::GetProperty(
         this, prop, this->Makefile->GetMessenger(), this->GetBacktrace())) {
     return result;
@@ -629,13 +625,13 @@ const char* cmGeneratorTarget::GetFilePrefixInternal(
     const char* prefixVar = this->Target->GetPrefixVariableInternal(artifact);
     if (!language.empty() && prefixVar && *prefixVar) {
       std::string langPrefix = prefixVar + std::string("_") + language;
-      targetPrefix = this->Makefile->GetDef(langPrefix);
+      targetPrefix = this->Makefile->GetDefinition(langPrefix);
     }
 
     // if there is no prefix on the target nor specific language
     // use the cmake definition.
     if (!targetPrefix && prefixVar) {
-      targetPrefix = this->Makefile->GetDef(prefixVar);
+      targetPrefix = this->Makefile->GetDefinition(prefixVar);
     }
   }
 
@@ -679,13 +675,13 @@ const char* cmGeneratorTarget::GetFileSuffixInternal(
     const char* suffixVar = this->Target->GetSuffixVariableInternal(artifact);
     if (!language.empty() && suffixVar && *suffixVar) {
       std::string langSuffix = suffixVar + std::string("_") + language;
-      targetSuffix = this->Makefile->GetDef(langSuffix);
+      targetSuffix = this->Makefile->GetDefinition(langSuffix);
     }
 
     // if there is no suffix on the target nor specific language
     // use the cmake definition.
     if (!targetSuffix && suffixVar) {
-      targetSuffix = this->Makefile->GetDef(suffixVar);
+      targetSuffix = this->Makefile->GetDefinition(suffixVar);
     }
   }
 
@@ -801,7 +797,8 @@ void cmGeneratorTarget::GetObjectSources(
 
 void cmGeneratorTarget::ComputeObjectMapping()
 {
-  auto const& configs = this->Makefile->GetGeneratorConfigs();
+  auto const& configs =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
   std::set<std::string> configSet(configs.begin(), configs.end());
   if (configSet == this->VisitedConfigsForObjects) {
     return;
@@ -813,18 +810,18 @@ void cmGeneratorTarget::ComputeObjectMapping()
   }
 }
 
-const char* cmGeneratorTarget::GetFeature(const std::string& feature,
-                                          const std::string& config) const
+cmProp cmGeneratorTarget::GetFeature(const std::string& feature,
+                                     const std::string& config) const
 {
   if (!config.empty()) {
     std::string featureConfig =
       cmStrCat(feature, '_', cmSystemTools::UpperCase(config));
     if (cmProp value = this->GetProperty(featureConfig)) {
-      return value->c_str();
+      return value;
     }
   }
   if (cmProp value = this->GetProperty(feature)) {
-    return value->c_str();
+    return value;
   }
   return this->LocalGenerator->GetFeature(feature, config);
 }
@@ -851,10 +848,9 @@ const char* cmGeneratorTarget::GetLinkPIEProperty(
 bool cmGeneratorTarget::IsIPOEnabled(std::string const& lang,
                                      std::string const& config) const
 {
-  const char* feature = "INTERPROCEDURAL_OPTIMIZATION";
-  const bool result = cmIsOn(this->GetFeature(feature, config));
+  cmProp feature = this->GetFeature("INTERPROCEDURAL_OPTIMIZATION", config);
 
-  if (!result) {
+  if (!cmIsOn(feature)) {
     // 'INTERPROCEDURAL_OPTIMIZATION' is off, no need to check policies
     return false;
   }
@@ -947,6 +943,61 @@ bool cmGeneratorTarget::HasExplicitObjectName(cmSourceFile const* file) const
   return it != this->ExplicitObjectName.end();
 }
 
+BTs<std::string> const* cmGeneratorTarget::GetLanguageStandardProperty(
+  std::string const& lang, std::string const& config) const
+{
+  std::string key = cmStrCat(cmSystemTools::UpperCase(config), '-', lang);
+  auto langStandardIter = this->LanguageStandardMap.find(key);
+  if (langStandardIter != this->LanguageStandardMap.end()) {
+    return &langStandardIter->second;
+  }
+
+  return this->Target->GetLanguageStandardProperty(
+    cmStrCat(lang, "_STANDARD"));
+}
+
+cmProp cmGeneratorTarget::GetLanguageStandard(std::string const& lang,
+                                              std::string const& config) const
+{
+  BTs<std::string> const* languageStandard =
+    this->GetLanguageStandardProperty(lang, config);
+
+  if (languageStandard) {
+    return &(languageStandard->Value);
+  }
+
+  return nullptr;
+}
+
+cmProp cmGeneratorTarget::GetPropertyWithPairedLanguageSupport(
+  std::string const& lang, const char* suffix) const
+{
+  cmProp propertyValue = this->Target->GetProperty(cmStrCat(lang, suffix));
+  if (propertyValue == nullptr) {
+    // Check if we should use the value set by another language.
+    if (lang == "OBJC") {
+      propertyValue = this->GetPropertyWithPairedLanguageSupport("C", suffix);
+    } else if (lang == "OBJCXX" || lang == "CUDA") {
+      propertyValue =
+        this->GetPropertyWithPairedLanguageSupport("CXX", suffix);
+    }
+  }
+  return propertyValue;
+}
+
+cmProp cmGeneratorTarget::GetLanguageExtensions(std::string const& lang) const
+{
+  return this->GetPropertyWithPairedLanguageSupport(lang, "_EXTENSIONS");
+}
+
+bool cmGeneratorTarget::GetLanguageStandardRequired(
+  std::string const& lang) const
+{
+  cmProp p =
+    this->GetPropertyWithPairedLanguageSupport(lang, "_STANDARD_REQUIRED");
+  return cmIsOn(p);
+}
+
 void cmGeneratorTarget::GetModuleDefinitionSources(
   std::vector<cmSourceFile const*>& data, const std::string& config) const
 {
@@ -1033,6 +1084,62 @@ std::vector<cmCustomCommand> const& cmGeneratorTarget::GetPostBuildCommands()
   return this->Target->GetPostBuildCommands();
 }
 
+void cmGeneratorTarget::AppendCustomCommandSideEffects(
+  std::set<cmGeneratorTarget const*>& sideEffects) const
+{
+  if (!this->GetPreBuildCommands().empty() ||
+      !this->GetPreLinkCommands().empty() ||
+      !this->GetPostBuildCommands().empty()) {
+    sideEffects.insert(this);
+  } else {
+    for (auto const& source : this->GetAllConfigSources()) {
+      if (source.Source->GetCustomCommand() != nullptr) {
+        sideEffects.insert(this);
+        break;
+      }
+    }
+  }
+}
+
+void cmGeneratorTarget::AppendLanguageSideEffects(
+  std::map<std::string, std::set<cmGeneratorTarget const*>>& sideEffects) const
+{
+  static const std::set<cm::string_view> LANGS_WITH_NO_SIDE_EFFECTS = {
+    "C"_s, "CXX"_s, "OBJC"_s, "OBJCXX"_s, "ASM"_s, "CUDA"_s,
+  };
+
+  for (auto const& lang : this->GetAllConfigCompileLanguages()) {
+    if (!LANGS_WITH_NO_SIDE_EFFECTS.count(lang)) {
+      sideEffects[lang].insert(this);
+    }
+  }
+}
+
+bool cmGeneratorTarget::IsInBuildSystem() const
+{
+  if (this->IsImported()) {
+    return false;
+  }
+  switch (this->Target->GetType()) {
+    case cmStateEnums::EXECUTABLE:
+    case cmStateEnums::STATIC_LIBRARY:
+    case cmStateEnums::SHARED_LIBRARY:
+    case cmStateEnums::MODULE_LIBRARY:
+    case cmStateEnums::OBJECT_LIBRARY:
+    case cmStateEnums::UTILITY:
+    case cmStateEnums::GLOBAL_TARGET:
+      return true;
+    case cmStateEnums::INTERFACE_LIBRARY:
+      // An INTERFACE library is in the build system if it has SOURCES.
+      if (!this->SourceEntries.empty()) {
+        return true;
+      }
+    case cmStateEnums::UNKNOWN_LIBRARY:
+      break;
+  }
+  return false;
+}
+
 bool cmGeneratorTarget::IsImported() const
 {
   return this->Target->IsImported();
@@ -1043,6 +1150,11 @@ bool cmGeneratorTarget::IsImportedGloballyVisible() const
   return this->Target->IsImportedGloballyVisible();
 }
 
+bool cmGeneratorTarget::CanCompileSources() const
+{
+  return this->Target->CanCompileSources();
+}
+
 const std::string& cmGeneratorTarget::GetLocationForBuild() const
 {
   static std::string location;
@@ -1055,10 +1167,10 @@ const std::string& cmGeneratorTarget::GetLocationForBuild() const
   // Now handle the deprecated build-time configuration location.
   std::string const noConfig;
   location = this->GetDirectory(noConfig);
-  const char* cfgid = this->Makefile->GetDefinition("CMAKE_CFG_INTDIR");
-  if (cfgid && strcmp(cfgid, ".") != 0) {
+  cmProp cfgid = this->Makefile->GetDefinition("CMAKE_CFG_INTDIR");
+  if (cfgid && (*cfgid != ".")) {
     location += "/";
-    location += cfgid;
+    location += *cfgid;
   }
 
   if (this->IsAppBundleOnApple()) {
@@ -1137,7 +1249,7 @@ bool cmGeneratorTarget::MaybeHaveInterfaceProperty(
 
     // If this target itself has a non-empty property value, we are done.
     cmProp p = this->GetProperty(prop);
-    maybeInterfaceProp = p && !p->empty();
+    maybeInterfaceProp = cmNonempty(p);
 
     // Otherwise, recurse to interface dependencies.
     if (!maybeInterfaceProp) {
@@ -1251,18 +1363,25 @@ std::string cmGeneratorTarget::EvaluateInterfaceProperty(
 }
 
 namespace {
-std::string AddSwiftInterfaceIncludeDirectories(
+
+enum class IncludeDirectoryFallBack
+{
+  BINARY,
+  OBJECT
+};
+
+std::string AddLangSpecificInterfaceIncludeDirectories(
   const cmGeneratorTarget* root, const cmGeneratorTarget* target,
-  const std::string& config, cmGeneratorExpressionDAGChecker* context)
+  const std::string& lang, const std::string& config,
+  const std::string& propertyName, IncludeDirectoryFallBack mode,
+  cmGeneratorExpressionDAGChecker* context)
 {
   cmGeneratorExpressionDAGChecker dag{ target->GetBacktrace(), target,
-                                       "Swift_MODULE_DIRECTORY", nullptr,
-                                       context };
+                                       propertyName, nullptr, context };
   switch (dag.Check()) {
     case cmGeneratorExpressionDAGChecker::SELF_REFERENCE:
-      dag.ReportError(nullptr,
-                      "$<TARGET_PROPERTY:" + target->GetName() +
-                        ",Swift_MODULE_DIRECTORY>");
+      dag.ReportError(
+        nullptr, "$<TARGET_PROPERTY:" + target->GetName() + ",propertyName");
       CM_FALLTHROUGH;
     case cmGeneratorExpressionDAGChecker::CYCLIC_REFERENCE:
       // No error. We just skip cyclic references.
@@ -1278,13 +1397,16 @@ std::string AddSwiftInterfaceIncludeDirectories(
         target->GetLinkInterfaceLibraries(config, root, true)) {
     for (const cmLinkItem& library : interface->Libraries) {
       if (const cmGeneratorTarget* dependency = library.Target) {
-        if (cm::contains(dependency->GetAllConfigCompileLanguages(),
-                         "Swift")) {
-          std::string value =
-            dependency->GetSafeProperty("Swift_MODULE_DIRECTORY");
+        if (cm::contains(dependency->GetAllConfigCompileLanguages(), lang)) {
+          auto* lg = dependency->GetLocalGenerator();
+          std::string value = dependency->GetSafeProperty(propertyName);
           if (value.empty()) {
-            value =
-              dependency->GetLocalGenerator()->GetCurrentBinaryDirectory();
+            if (mode == IncludeDirectoryFallBack::BINARY) {
+              value = lg->GetCurrentBinaryDirectory();
+            } else if (mode == IncludeDirectoryFallBack::OBJECT) {
+              value = cmStrCat(lg->GetCurrentBinaryDirectory(), '/',
+                               lg->GetTargetDirectory(dependency));
+            }
           }
 
           if (!directories.empty()) {
@@ -1298,35 +1420,39 @@ std::string AddSwiftInterfaceIncludeDirectories(
   return directories;
 }
 
-void AddSwiftImplicitIncludeDirectories(
-  const cmGeneratorTarget* target, const std::string& config,
-  EvaluatedTargetPropertyEntries& entries)
+void AddLangSpecificImplicitIncludeDirectories(
+  const cmGeneratorTarget* target, const std::string& lang,
+  const std::string& config, const std::string& propertyName,
+  IncludeDirectoryFallBack mode, EvaluatedTargetPropertyEntries& entries)
 {
   if (const auto* libraries = target->GetLinkImplementationLibraries(config)) {
     cmGeneratorExpressionDAGChecker dag{ target->GetBacktrace(), target,
-                                         "Swift_MODULE_DIRECTORY", nullptr,
-                                         nullptr };
+                                         propertyName, nullptr, nullptr };
 
     for (const cmLinkImplItem& library : libraries->Libraries) {
       if (const cmGeneratorTarget* dependency = library.Target) {
-        if (dependency->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+        if (!dependency->IsInBuildSystem()) {
           continue;
         }
-        if (cm::contains(dependency->GetAllConfigCompileLanguages(),
-                         "Swift")) {
+        if (cm::contains(dependency->GetAllConfigCompileLanguages(), lang)) {
+          auto* lg = dependency->GetLocalGenerator();
           EvaluatedTargetPropertyEntry entry{ library, library.Backtrace };
 
-          if (cmProp val = dependency->GetProperty("Swift_MODULE_DIRECTORY")) {
+          if (cmProp val = dependency->GetProperty(propertyName)) {
             entry.Values.emplace_back(*val);
           } else {
-            entry.Values.emplace_back(
-              dependency->GetLocalGenerator()->GetCurrentBinaryDirectory());
+            if (mode == IncludeDirectoryFallBack::BINARY) {
+              entry.Values.emplace_back(lg->GetCurrentBinaryDirectory());
+            } else if (mode == IncludeDirectoryFallBack::OBJECT) {
+              entry.Values.emplace_back(
+                dependency->GetObjectDirectory(config));
+            }
           }
 
-          cmExpandList(AddSwiftInterfaceIncludeDirectories(target, dependency,
-                                                           config, &dag),
-                       entry.Values);
-
+          cmExpandList(
+            AddLangSpecificInterfaceIncludeDirectories(
+              target, dependency, lang, config, propertyName, mode, &dag),
+            entry.Values);
           entries.Entries.emplace_back(std::move(entry));
         }
       }
@@ -1466,7 +1592,6 @@ std::vector<BT<std::string>> cmGeneratorTarget::GetSourceFilePaths(
   std::string const& config) const
 {
   std::vector<BT<std::string>> files;
-  assert(this->GetType() != cmStateEnums::INTERFACE_LIBRARY);
 
   if (!this->LocalGenerator->GetGlobalGenerator()->GetConfigureDoneCMP0026()) {
     // At configure-time, this method can be called as part of getting the
@@ -1658,9 +1783,11 @@ void cmGeneratorTarget::ComputeKindedSources(KindedSources& files,
     std::string ext = cmSystemTools::LowerCase(sf->GetExtension());
     if (sf->GetCustomCommand()) {
       kind = SourceKindCustomCommand;
-      // XXX(clang-tidy): https://bugs.llvm.org/show_bug.cgi?id=44165
-      // NOLINTNEXTLINE(bugprone-branch-clone)
-    } else if (this->Target->GetType() == cmStateEnums::UTILITY) {
+    } else if (this->Target->GetType() == cmStateEnums::UTILITY ||
+               this->Target->GetType() == cmStateEnums::INTERFACE_LIBRARY
+               // XXX(clang-tidy): https://bugs.llvm.org/show_bug.cgi?id=44165
+               // NOLINTNEXTLINE(bugprone-branch-clone)
+    ) {
       kind = SourceKindExtra;
     } else if (this->IsSourceFilePartOfUnityBatch(sf->ResolveFullPath())) {
       kind = SourceKindUnityBatched;
@@ -1726,8 +1853,8 @@ cmGeneratorTarget::GetAllConfigSources() const
 
 void cmGeneratorTarget::ComputeAllConfigSources() const
 {
-  std::vector<std::string> configs;
-  this->Makefile->GetConfigurations(configs);
+  std::vector<std::string> configs =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
   std::map<cmSourceFile const*, size_t> index;
 
@@ -1787,12 +1914,12 @@ std::string cmGeneratorTarget::GetCompilePDBName(
   std::string configUpper = cmSystemTools::UpperCase(config);
   std::string configProp = cmStrCat("COMPILE_PDB_NAME_", configUpper);
   cmProp config_name = this->GetProperty(configProp);
-  if (config_name && !config_name->empty()) {
+  if (cmNonempty(config_name)) {
     return prefix + *config_name + ".pdb";
   }
 
   cmProp name = this->GetProperty("COMPILE_PDB_NAME");
-  if (name && !name->empty()) {
+  if (cmNonempty(name)) {
     return prefix + *name + ".pdb";
   }
 
@@ -1938,13 +2065,13 @@ bool cmGeneratorTarget::IsChrpathUsed(const std::string& config) const
   if (!ll.empty()) {
     std::string sepVar =
       cmStrCat("CMAKE_SHARED_LIBRARY_RUNTIME_", ll, "_FLAG_SEP");
-    const char* sep = this->Makefile->GetDefinition(sepVar);
-    if (sep && *sep) {
+    cmProp sep = this->Makefile->GetDefinition(sepVar);
+    if (cmNonempty(sep)) {
       // TODO: Add ELF check to ABI detection and get rid of
       // CMAKE_EXECUTABLE_FORMAT.
-      if (const char* fmt =
+      if (cmProp fmt =
             this->Makefile->GetDefinition("CMAKE_EXECUTABLE_FORMAT")) {
-        return strcmp(fmt, "ELF") == 0;
+        return (*fmt == "ELF");
       }
     }
   }
@@ -2153,6 +2280,12 @@ bool cmGeneratorTarget::IsBundleOnApple() const
     this->IsCFBundleOnApple();
 }
 
+bool cmGeneratorTarget::IsWin32Executable(const std::string& config) const
+{
+  return cmIsOn(cmGeneratorExpression::Evaluate(
+    this->GetSafeProperty("WIN32_EXECUTABLE"), this->LocalGenerator, config));
+}
+
 std::string cmGeneratorTarget::GetCFBundleDirectory(
   const std::string& config, BundleDirectoryLevel level) const
 {
@@ -2239,7 +2372,7 @@ std::string cmGeneratorTarget::GetInstallNameDirForInstallTree(
     cmProp install_name_dir = this->GetProperty("INSTALL_NAME_DIR");
 
     if (this->CanGenerateInstallNameDir(INSTALL_NAME_FOR_INSTALL)) {
-      if (install_name_dir && !install_name_dir->empty()) {
+      if (cmNonempty(install_name_dir)) {
         dir = *install_name_dir;
         cmGeneratorExpression::ReplaceInstallPrefix(dir, installPrefix);
         dir =
@@ -2385,6 +2518,12 @@ private:
 cmGeneratorTarget::LinkClosure const* cmGeneratorTarget::GetLinkClosure(
   const std::string& config) const
 {
+  // There is no link implementation for targets that cannot compile sources.
+  if (!this->CanCompileSources()) {
+    static LinkClosure const empty = { {}, {} };
+    return &empty;
+  }
+
   std::string key(cmSystemTools::UpperCase(config));
   auto i = this->LinkClosureMap.find(key);
   if (i == this->LinkClosureMap.end()) {
@@ -2701,6 +2840,12 @@ const std::vector<const cmGeneratorTarget*>&
 cmGeneratorTarget::GetLinkImplementationClosure(
   const std::string& config) const
 {
+  // There is no link implementation for targets that cannot compile sources.
+  if (!this->CanCompileSources()) {
+    static std::vector<const cmGeneratorTarget*> const empty;
+    return empty;
+  }
+
   LinkImplClosure& tgts = this->LinkImplClosureMap[config];
   if (!tgts.Done) {
     tgts.Done = true;
@@ -2708,6 +2853,7 @@ cmGeneratorTarget::GetLinkImplementationClosure(
 
     cmLinkImplementationLibraries const* impl =
       this->GetLinkImplementationLibraries(config);
+    assert(impl);
 
     for (cmLinkImplItem const& lib : impl->Libraries) {
       processILibs(config, this, lib,
@@ -2757,29 +2903,26 @@ cmTargetTraceDependencies::cmTargetTraceDependencies(cmGeneratorTarget* target)
   this->CurrentEntry = nullptr;
 
   // Queue all the source files already specified for the target.
-  if (target->GetType() != cmStateEnums::INTERFACE_LIBRARY) {
-    std::set<cmSourceFile*> emitted;
-    std::vector<std::string> const& configs =
-      this->Makefile->GetGeneratorConfigs();
-    for (std::string const& c : configs) {
-      std::vector<cmSourceFile*> sources;
-      this->GeneratorTarget->GetSourceFiles(sources, c);
-      for (cmSourceFile* sf : sources) {
-        const std::set<cmGeneratorTarget const*> tgts =
-          this->GlobalGenerator->GetFilenameTargetDepends(sf);
-        if (cm::contains(tgts, this->GeneratorTarget)) {
-          std::ostringstream e;
-          e << "Evaluation output file\n  \"" << sf->ResolveFullPath()
-            << "\"\ndepends on the sources of a target it is used in.  This "
-               "is a dependency loop and is not allowed.";
-          this->GeneratorTarget->LocalGenerator->IssueMessage(
-            MessageType::FATAL_ERROR, e.str());
-          return;
-        }
-        if (emitted.insert(sf).second &&
-            this->SourcesQueued.insert(sf).second) {
-          this->SourceQueue.push(sf);
-        }
+  std::set<cmSourceFile*> emitted;
+  std::vector<std::string> const& configs =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
+  for (std::string const& c : configs) {
+    std::vector<cmSourceFile*> sources;
+    this->GeneratorTarget->GetSourceFiles(sources, c);
+    for (cmSourceFile* sf : sources) {
+      const std::set<cmGeneratorTarget const*> tgts =
+        this->GlobalGenerator->GetFilenameTargetDepends(sf);
+      if (cm::contains(tgts, this->GeneratorTarget)) {
+        std::ostringstream e;
+        e << "Evaluation output file\n  \"" << sf->ResolveFullPath()
+          << "\"\ndepends on the sources of a target it is used in.  This "
+             "is a dependency loop and is not allowed.";
+        this->GeneratorTarget->LocalGenerator->IssueMessage(
+          MessageType::FATAL_ERROR, e.str());
+        return;
+      }
+      if (emitted.insert(sf).second && this->SourcesQueued.insert(sf).second) {
+        this->SourceQueue.push(sf);
       }
     }
   }
@@ -2971,7 +3114,7 @@ void cmTargetTraceDependencies::CheckCustomCommand(cmCustomCommand const& cc)
   // Queue the custom command dependencies.
   std::set<std::string> emitted;
   std::vector<std::string> const& configs =
-    this->Makefile->GetGeneratorConfigs();
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
   for (std::string const& conf : configs) {
     this->FollowCommandDepends(cc, conf, emitted);
   }
@@ -3111,7 +3254,7 @@ void cmGeneratorTarget::AddCUDAArchitectureFlags(std::string& flags) const
         } else {
           this->Makefile->IssueMessage(
             MessageType::FATAL_ERROR,
-            "Uknown CUDA architecture specifier \"" + std::string(specifier) +
+            "Unknown CUDA architecture specifier \"" + std::string(specifier) +
               "\".");
         }
       }
@@ -3159,6 +3302,27 @@ void cmGeneratorTarget::AddCUDAArchitectureFlags(std::string& flags) const
   }
 }
 
+void cmGeneratorTarget::AddISPCTargetFlags(std::string& flags) const
+{
+  const std::string& property = this->GetSafeProperty("ISPC_INSTRUCTION_SETS");
+
+  // If ISPC_TARGET is false we don't add any architectures.
+  if (cmIsOff(property)) {
+    return;
+  }
+
+  std::string const& compiler =
+    this->Makefile->GetSafeDefinition("CMAKE_ISPC_COMPILER_ID");
+
+  if (compiler == "Intel") {
+    std::vector<std::string> targets;
+    cmExpandList(property, targets);
+    if (!targets.empty()) {
+      flags += cmStrCat(" --target=", cmWrap("", targets, "", ","));
+    }
+  }
+}
+
 void cmGeneratorTarget::AddCUDAToolkitFlags(std::string& flags) const
 {
   std::string const& compiler =
@@ -3353,30 +3517,52 @@ std::vector<BT<std::string>> cmGeneratorTarget::GetIncludeDirectories(
     this, config, lang, &dagChecker, this->IncludeDirectoriesEntries);
 
   if (lang == "Swift") {
-    AddSwiftImplicitIncludeDirectories(this, config, entries);
+    AddLangSpecificImplicitIncludeDirectories(
+      this, lang, config, "Swift_MODULE_DIRECTORY",
+      IncludeDirectoryFallBack::BINARY, entries);
+  }
+
+  if (this->CanCompileSources() && (lang != "Swift" && lang != "Fortran")) {
+
+    const std::string propertyName = "ISPC_HEADER_DIRECTORY";
+
+    // If this target has ISPC sources make sure to add the header
+    // directory to other compilation units
+    if (cm::contains(this->GetAllConfigCompileLanguages(), "ISPC")) {
+      if (cmProp val = this->GetProperty(propertyName)) {
+        includes.emplace_back(*val);
+      } else {
+        includes.emplace_back(this->GetObjectDirectory(config));
+      }
+    }
+
+    AddLangSpecificImplicitIncludeDirectories(
+      this, "ISPC", config, propertyName, IncludeDirectoryFallBack::OBJECT,
+      entries);
   }
 
   AddInterfaceEntries(this, config, "INTERFACE_INCLUDE_DIRECTORIES", lang,
                       &dagChecker, entries);
 
   if (this->Makefile->IsOn("APPLE")) {
-    cmLinkImplementationLibraries const* impl =
-      this->GetLinkImplementationLibraries(config);
-    for (cmLinkImplItem const& lib : impl->Libraries) {
-      std::string libDir = cmSystemTools::CollapseFullPath(
-        lib.AsStr(), this->Makefile->GetHomeOutputDirectory());
-
-      static cmsys::RegularExpression frameworkCheck(
-        "(.*\\.framework)(/Versions/[^/]+)?/[^/]+$");
-      if (!frameworkCheck.find(libDir)) {
-        continue;
-      }
+    if (cmLinkImplementationLibraries const* impl =
+          this->GetLinkImplementationLibraries(config)) {
+      for (cmLinkImplItem const& lib : impl->Libraries) {
+        std::string libDir = cmSystemTools::CollapseFullPath(
+          lib.AsStr(), this->Makefile->GetHomeOutputDirectory());
+
+        static cmsys::RegularExpression frameworkCheck(
+          "(.*\\.framework)(/Versions/[^/]+)?/[^/]+$");
+        if (!frameworkCheck.find(libDir)) {
+          continue;
+        }
 
-      libDir = frameworkCheck.match(1);
+        libDir = frameworkCheck.match(1);
 
-      EvaluatedTargetPropertyEntry ee(lib, cmListFileBacktrace());
-      ee.Values.emplace_back(std::move(libDir));
-      entries.Entries.emplace_back(std::move(ee));
+        EvaluatedTargetPropertyEntry ee(lib, cmListFileBacktrace());
+        ee.Values.emplace_back(std::move(libDir));
+        entries.Entries.emplace_back(std::move(ee));
+      }
     }
   }
 
@@ -3744,8 +3930,8 @@ std::string cmGeneratorTarget::GetPchHeader(const std::string& config,
 
     const std::string filename_tmp = cmStrCat(filename, ".tmp");
     if (!pchReuseFrom) {
-      auto pchPrologue = this->Makefile->GetDefinition("CMAKE_PCH_PROLOGUE");
-      auto pchEpilogue = this->Makefile->GetDefinition("CMAKE_PCH_EPILOGUE");
+      cmProp pchPrologue = this->Makefile->GetDefinition("CMAKE_PCH_PROLOGUE");
+      cmProp pchEpilogue = this->Makefile->GetDefinition("CMAKE_PCH_EPILOGUE");
 
       std::string firstHeaderOnDisk;
       {
@@ -3754,7 +3940,7 @@ std::string cmGeneratorTarget::GetPchHeader(const std::string& config,
           this->GetGlobalGenerator()->GetMakefileEncoding());
         file << "/* generated by CMake */\n\n";
         if (pchPrologue) {
-          file << pchPrologue << "\n";
+          file << *pchPrologue << "\n";
         }
         if (this->GetGlobalGenerator()->IsXcode()) {
           file << "#ifndef CMAKE_SKIP_PRECOMPILE_HEADERS\n";
@@ -3784,7 +3970,7 @@ std::string cmGeneratorTarget::GetPchHeader(const std::string& config,
           file << "#endif // CMAKE_SKIP_PRECOMPILE_HEADERS\n";
         }
         if (pchEpilogue) {
-          file << pchEpilogue << "\n";
+          file << *pchEpilogue << "\n";
         }
       }
 
@@ -3827,7 +4013,7 @@ std::string cmGeneratorTarget::GetPchSource(const std::string& config,
       cmStrCat(generatorTarget->LocalGenerator->GetCurrentBinaryDirectory(),
                "/CMakeFiles/", generatorTarget->GetName(), ".dir/cmake_pch");
 
-    // For GCC the source extension will be tranformed into .h[xx].gch
+    // For GCC the source extension will be transformed into .h[xx].gch
     if (!this->Makefile->IsOn("CMAKE_LINK_PCH")) {
       const std::map<std::string, std::string> languageToExtension = {
         { "C", ".h.c" },
@@ -4414,12 +4600,75 @@ void cmGeneratorTarget::ComputeTargetManifest(const std::string& config) const
 
 bool cmGeneratorTarget::ComputeCompileFeatures(std::string const& config) const
 {
+  // Compute the language standard based on the compile features.
+  cmStandardLevelResolver standardResolver(this->Makefile);
   std::vector<BT<std::string>> features = this->GetCompileFeatures(config);
   for (BT<std::string> const& f : features) {
-    if (!this->Makefile->AddRequiredTargetFeature(this->Target, f.Value)) {
+    std::string lang;
+    if (!standardResolver.CompileFeatureKnown(this->Target->GetName(), f.Value,
+                                              lang, nullptr)) {
+      return false;
+    }
+
+    std::string key = cmStrCat(cmSystemTools::UpperCase(config), '-', lang);
+    cmProp currentLanguageStandard = this->GetLanguageStandard(lang, config);
+
+    std::string newRequiredStandard;
+    if (!standardResolver.GetNewRequiredStandard(
+          this->Target->GetName(), f.Value, currentLanguageStandard,
+          newRequiredStandard)) {
       return false;
     }
+
+    if (!newRequiredStandard.empty()) {
+      BTs<std::string>& languageStandardProperty =
+        this->LanguageStandardMap[key];
+      if (languageStandardProperty.Value != newRequiredStandard) {
+        languageStandardProperty.Value = newRequiredStandard;
+        languageStandardProperty.Backtraces.clear();
+      }
+      languageStandardProperty.Backtraces.emplace_back(f.Backtrace);
+    }
+  }
+
+  return true;
+}
+
+bool cmGeneratorTarget::ComputeCompileFeatures(
+  std::string const& config, std::set<LanguagePair> const& languagePairs) const
+{
+  for (const auto& language : languagePairs) {
+    BTs<std::string> const* generatorTargetLanguageStandard =
+      this->GetLanguageStandardProperty(language.first, config);
+    if (!generatorTargetLanguageStandard) {
+      // If the standard isn't explicitly set we copy it over from the
+      // specified paired language.
+      std::string key =
+        cmStrCat(cmSystemTools::UpperCase(config), '-', language.first);
+      BTs<std::string> const* standardToCopy =
+        this->GetLanguageStandardProperty(language.second, config);
+      if (standardToCopy != nullptr) {
+        this->LanguageStandardMap[key] = *standardToCopy;
+        generatorTargetLanguageStandard = &this->LanguageStandardMap[key];
+      } else {
+        cmProp defaultStandard = this->Makefile->GetDefinition(
+          cmStrCat("CMAKE_", language.second, "_STANDARD_DEFAULT"));
+        if (defaultStandard != nullptr) {
+          this->LanguageStandardMap[key] = BTs<std::string>(*defaultStandard);
+          generatorTargetLanguageStandard = &this->LanguageStandardMap[key];
+        }
+      }
+
+      // Custom updates for the CUDA standard.
+      if (generatorTargetLanguageStandard != nullptr &&
+          language.first == "CUDA") {
+        if (generatorTargetLanguageStandard->Value == "98") {
+          this->LanguageStandardMap[key].Value = "03";
+        }
+      }
+    }
   }
+
   return true;
 }
 
@@ -4547,12 +4796,11 @@ cmGeneratorTarget::Names cmGeneratorTarget::GetLibraryNames(
     // The library's soname.
     this->ComputeVersionedName(targetNames.SharedObject, prefix,
                                targetNames.Base, suffix, targetNames.Output,
-                               (soversion ? soversion->c_str() : nullptr));
+                               cmToCStr(soversion));
 
     // The library's real name on disk.
     this->ComputeVersionedName(targetNames.Real, prefix, targetNames.Base,
-                               suffix, targetNames.Output,
-                               (version ? version->c_str() : nullptr));
+                               suffix, targetNames.Output, cmToCStr(version));
   }
 
   // The import library name.
@@ -4588,10 +4836,7 @@ cmGeneratorTarget::Names cmGeneratorTarget::GetExecutableNames(
   const char* version = nullptr;
 #else
   // Check for executable version properties.
-  const char* version = nullptr;
-  if (cmProp p = this->GetProperty("VERSION")) {
-    version = p->c_str();
-  }
+  const char* version = cmToCStr(this->GetProperty("VERSION"));
   if (this->GetType() != cmStateEnums::EXECUTABLE ||
       this->Makefile->IsOn("XCODE")) {
     version = nullptr;
@@ -4843,6 +5088,11 @@ void cmGeneratorTarget::GetTargetObjectNames(
     assert(!map_it->second.empty());
     objects.push_back(map_it->second);
   }
+
+  auto ispcObjects = this->GetGeneratedISPCObjects(config);
+  for (std::string const& output : ispcObjects) {
+    objects.push_back(cmSystemTools::GetFilenameName(output));
+  }
 }
 
 bool cmGeneratorTarget::StrictTargetComparison::operator()(
@@ -5297,8 +5547,7 @@ bool getTypedProperty<bool>(cmGeneratorTarget const* tgt,
   }
 
   cmProp value = tgt->GetProperty(prop);
-  return cmIsOn(
-    genexInterpreter->Evaluate(value ? value->c_str() : nullptr, prop));
+  return cmIsOn(genexInterpreter->Evaluate(value ? *value : "", prop));
 }
 
 template <>
@@ -5309,11 +5558,10 @@ const char* getTypedProperty<const char*>(
   cmProp value = tgt->GetProperty(prop);
 
   if (genexInterpreter == nullptr) {
-    return value ? value->c_str() : nullptr;
+    return cmToCStr(value);
   }
 
-  return genexInterpreter->Evaluate(value ? value->c_str() : nullptr, prop)
-    .c_str();
+  return genexInterpreter->Evaluate(value ? *value : "", prop).c_str();
 }
 
 template <>
@@ -5324,10 +5572,10 @@ std::string getTypedProperty<std::string>(
   cmProp value = tgt->GetProperty(prop);
 
   if (genexInterpreter == nullptr) {
-    return valueAsString(value ? value->c_str() : nullptr);
+    return valueAsString(cmToCStr(value));
   }
 
-  return genexInterpreter->Evaluate(value ? value->c_str() : nullptr, prop);
+  return genexInterpreter->Evaluate(value ? *value : "", prop);
 }
 
 template <typename PropertyType>
@@ -5726,9 +5974,9 @@ std::string cmGeneratorTarget::GetRuntimeLinkLibrary(
 {
   // This is activated by the presence of a default selection whether or
   // not it is overridden by a property.
-  cmProp runtimeLibraryDefault = this->Makefile->GetDef(
+  cmProp runtimeLibraryDefault = this->Makefile->GetDefinition(
     cmStrCat("CMAKE_", lang, "_RUNTIME_LIBRARY_DEFAULT"));
-  if (!runtimeLibraryDefault || runtimeLibraryDefault->empty()) {
+  if (!cmNonempty(runtimeLibraryDefault)) {
     return std::string();
   }
   cmProp runtimeLibraryValue =
@@ -5766,7 +6014,7 @@ std::string cmGeneratorTarget::CreateFortranModuleDirectory(
       target_mod_dir = default_mod_dir;
     }
   }
-  const char* moddir_flag =
+  cmProp moddir_flag =
     this->Makefile->GetDefinition("CMAKE_Fortran_MODDIR_FLAG");
   if (!target_mod_dir.empty() && moddir_flag) {
     // Compute the full path to the module directory.
@@ -5785,6 +6033,66 @@ std::string cmGeneratorTarget::CreateFortranModuleDirectory(
   return mod_dir;
 }
 
+void cmGeneratorTarget::AddISPCGeneratedHeader(std::string const& header,
+                                               std::string const& config)
+{
+  std::string config_upper;
+  if (!config.empty()) {
+    config_upper = cmSystemTools::UpperCase(config);
+  }
+  auto iter = this->ISPCGeneratedHeaders.find(config_upper);
+  if (iter == this->ISPCGeneratedHeaders.end()) {
+    std::vector<std::string> headers;
+    headers.emplace_back(header);
+    this->ISPCGeneratedHeaders.insert({ config_upper, headers });
+  } else {
+    iter->second.emplace_back(header);
+  }
+}
+
+std::vector<std::string> cmGeneratorTarget::GetGeneratedISPCHeaders(
+  std::string const& config) const
+{
+  std::string config_upper;
+  if (!config.empty()) {
+    config_upper = cmSystemTools::UpperCase(config);
+  }
+  auto iter = this->ISPCGeneratedHeaders.find(config_upper);
+  if (iter == this->ISPCGeneratedHeaders.end()) {
+    return std::vector<std::string>{};
+  }
+  return iter->second;
+}
+
+void cmGeneratorTarget::AddISPCGeneratedObject(std::vector<std::string>&& objs,
+                                               std::string const& config)
+{
+  std::string config_upper;
+  if (!config.empty()) {
+    config_upper = cmSystemTools::UpperCase(config);
+  }
+  auto iter = this->ISPCGeneratedObjects.find(config_upper);
+  if (iter == this->ISPCGeneratedObjects.end()) {
+    this->ISPCGeneratedObjects.insert({ config_upper, objs });
+  } else {
+    iter->second.insert(iter->second.end(), objs.begin(), objs.end());
+  }
+}
+
+std::vector<std::string> cmGeneratorTarget::GetGeneratedISPCObjects(
+  std::string const& config) const
+{
+  std::string config_upper;
+  if (!config.empty()) {
+    config_upper = cmSystemTools::UpperCase(config);
+  }
+  auto iter = this->ISPCGeneratedObjects.find(config_upper);
+  if (iter == this->ISPCGeneratedObjects.end()) {
+    return std::vector<std::string>{};
+  }
+  return iter->second;
+}
+
 std::string cmGeneratorTarget::GetFrameworkVersion() const
 {
   assert(this->GetType() != cmStateEnums::INTERFACE_LIBRARY);
@@ -6164,21 +6472,16 @@ bool cmGeneratorTarget::ComputeOutputDir(const std::string& config,
   // Look for a target property defining the target output directory
   // based on the target type.
   std::string targetTypeName = this->GetOutputTargetType(artifact);
-  const char* propertyName = nullptr;
-  std::string propertyNameStr = targetTypeName;
-  if (!propertyNameStr.empty()) {
-    propertyNameStr += "_OUTPUT_DIRECTORY";
-    propertyName = propertyNameStr.c_str();
+  std::string propertyName;
+  if (!targetTypeName.empty()) {
+    propertyName = cmStrCat(targetTypeName, "_OUTPUT_DIRECTORY");
   }
 
   // Check for a per-configuration output directory target property.
   std::string configUpper = cmSystemTools::UpperCase(conf);
-  const char* configProp = nullptr;
-  std::string configPropStr = targetTypeName;
-  if (!configPropStr.empty()) {
-    configPropStr += "_OUTPUT_DIRECTORY_";
-    configPropStr += configUpper;
-    configProp = configPropStr.c_str();
+  std::string configProp;
+  if (!targetTypeName.empty()) {
+    configProp = cmStrCat(targetTypeName, "_OUTPUT_DIRECTORY_", configUpper);
   }
 
   // Select an output directory.
@@ -6239,22 +6542,17 @@ bool cmGeneratorTarget::ComputePDBOutputDir(const std::string& kind,
 {
   // Look for a target property defining the target output directory
   // based on the target type.
-  const char* propertyName = nullptr;
-  std::string propertyNameStr = kind;
-  if (!propertyNameStr.empty()) {
-    propertyNameStr += "_OUTPUT_DIRECTORY";
-    propertyName = propertyNameStr.c_str();
+  std::string propertyName;
+  if (!kind.empty()) {
+    propertyName = cmStrCat(kind, "_OUTPUT_DIRECTORY");
   }
   std::string conf = config;
 
   // Check for a per-configuration output directory target property.
   std::string configUpper = cmSystemTools::UpperCase(conf);
-  const char* configProp = nullptr;
-  std::string configPropStr = kind;
-  if (!configPropStr.empty()) {
-    configPropStr += "_OUTPUT_DIRECTORY_";
-    configPropStr += configUpper;
-    configProp = configPropStr.c_str();
+  std::string configProp;
+  if (!kind.empty()) {
+    configProp = cmStrCat(kind, "_OUTPUT_DIRECTORY_", configUpper);
   }
 
   // Select an output directory.
@@ -6410,15 +6708,20 @@ void cmGeneratorTarget::ComputeLinkInterfaceLibraries(
                           iface.HadHeadSensitiveCondition,
                           iface.HadContextSensitiveCondition,
                           iface.HadLinkLanguageSensitiveCondition);
-  } else if (!cmp0022NEW)
+    return;
+  }
+
   // If CMP0022 is NEW then the plain tll signature sets the
   // INTERFACE_LINK_LIBRARIES, so if we get here then the project
   // cleared the property explicitly and we should not fall back
   // to the link implementation.
-  {
-    // The link implementation is the default link interface.
-    cmLinkImplementationLibraries const* impl =
-      this->GetLinkImplementationLibrariesInternal(config, headTarget);
+  if (cmp0022NEW) {
+    return;
+  }
+
+  // The link implementation is the default link interface.
+  if (cmLinkImplementationLibraries const* impl =
+        this->GetLinkImplementationLibrariesInternal(config, headTarget)) {
     iface.Libraries.insert(iface.Libraries.end(), impl->Libraries.begin(),
                            impl->Libraries.end());
     if (this->GetPolicyStatusCMP0022() == cmPolicies::WARN &&
@@ -6712,8 +7015,8 @@ const cmLinkImplementation* cmGeneratorTarget::GetLinkImplementation(
 const cmLinkImplementation* cmGeneratorTarget::GetLinkImplementation(
   const std::string& config, bool secondPass) const
 {
-  // There is no link implementation for imported targets.
-  if (this->IsImported()) {
+  // There is no link implementation for targets that cannot compile sources.
+  if (!this->CanCompileSources()) {
     return nullptr;
   }
 
@@ -6737,7 +7040,7 @@ bool cmGeneratorTarget::GetConfigCommonSourceFiles(
   std::vector<cmSourceFile*>& files) const
 {
   std::vector<std::string> const& configs =
-    this->Makefile->GetGeneratorConfigs();
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
   auto it = configs.begin();
   const std::string& firstConfig = *it;
@@ -6861,7 +7164,7 @@ std::string cmGeneratorTarget::CheckCMP0004(std::string const& item) const
 bool cmGeneratorTarget::IsDeprecated() const
 {
   cmProp deprecation = this->GetProperty("DEPRECATION");
-  return deprecation && !deprecation->empty();
+  return cmNonempty(deprecation);
 }
 
 std::string cmGeneratorTarget::GetDeprecation() const
@@ -6876,6 +7179,11 @@ std::string cmGeneratorTarget::GetDeprecation() const
 void cmGeneratorTarget::GetLanguages(std::set<std::string>& languages,
                                      const std::string& config) const
 {
+  // Targets that do not compile anything have no languages.
+  if (!this->CanCompileSources()) {
+    return;
+  }
+
   std::vector<cmSourceFile*> sourceFiles;
   this->GetSourceFiles(sourceFiles, config);
   for (cmSourceFile* src : sourceFiles) {
@@ -6926,7 +7234,7 @@ bool cmGeneratorTarget::IsCSharpOnly() const
   // Consider an explicit linker language property, but *not* the
   // computed linker language that may depend on linked targets.
   cmProp linkLang = this->GetProperty("LINKER_LANGUAGE");
-  if (linkLang && !linkLang->empty()) {
+  if (cmNonempty(linkLang)) {
     languages.insert(*linkLang);
   }
   return languages.size() == 1 && languages.count("CSharp") > 0;
@@ -6971,8 +7279,8 @@ cmLinkImplementationLibraries const*
 cmGeneratorTarget::GetLinkImplementationLibrariesInternal(
   const std::string& config, cmGeneratorTarget const* head) const
 {
-  // There is no link implementation for imported targets.
-  if (this->IsImported()) {
+  // There is no link implementation for targets that cannot compile sources.
+  if (!this->CanCompileSources()) {
     return nullptr;
   }
 
diff --git a/Source/cmGeneratorTarget.h b/Source/cmGeneratorTarget.h
index 3aedbf5..330d784 100644
--- a/Source/cmGeneratorTarget.h
+++ b/Source/cmGeneratorTarget.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGeneratorTarget_h
-#define cmGeneratorTarget_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -45,14 +44,22 @@ public:
 
   cmGlobalGenerator* GetGlobalGenerator() const;
 
+  bool IsInBuildSystem() const;
   bool IsImported() const;
   bool IsImportedGloballyVisible() const;
+  bool CanCompileSources() const;
   const std::string& GetLocation(const std::string& config) const;
 
   std::vector<cmCustomCommand> const& GetPreBuildCommands() const;
   std::vector<cmCustomCommand> const& GetPreLinkCommands() const;
   std::vector<cmCustomCommand> const& GetPostBuildCommands() const;
 
+  void AppendCustomCommandSideEffects(
+    std::set<cmGeneratorTarget const*>& sideEffects) const;
+  void AppendLanguageSideEffects(
+    std::map<std::string, std::set<cmGeneratorTarget const*>>& sideEffects)
+    const;
+
 #define DECLARE_TARGET_POLICY(POLICY)                                         \
   cmPolicies::PolicyStatus GetPolicyStatus##POLICY() const                    \
   {                                                                           \
@@ -148,6 +155,16 @@ public:
   bool HasExplicitObjectName(cmSourceFile const* file) const;
   void AddExplicitObjectName(cmSourceFile const* sf);
 
+  BTs<std::string> const* GetLanguageStandardProperty(
+    std::string const& lang, std::string const& config) const;
+
+  cmProp GetLanguageStandard(std::string const& lang,
+                             std::string const& config) const;
+
+  cmProp GetLanguageExtensions(std::string const& lang) const;
+
+  bool GetLanguageStandardRequired(std::string const& lang) const;
+
   void GetModuleDefinitionSources(std::vector<cmSourceFile const*>&,
                                   const std::string& config) const;
   void GetExternalObjects(std::vector<cmSourceFile const*>&,
@@ -165,8 +182,8 @@ public:
 
   void ComputeObjectMapping();
 
-  const char* GetFeature(const std::string& feature,
-                         const std::string& config) const;
+  cmProp GetFeature(const std::string& feature,
+                    const std::string& config) const;
 
   const char* GetLinkPIEProperty(const std::string& config) const;
 
@@ -266,6 +283,9 @@ public:
       or CFBundle on Apple.  */
   bool IsBundleOnApple() const;
 
+  /** Return whether this target is a Win32 executable */
+  bool IsWin32Executable(const std::string& config) const;
+
   /** Get the full name of the target according to the settings in its
       makefile.  */
   std::string GetFullName(const std::string& config,
@@ -428,6 +448,8 @@ public:
   void AddCUDAArchitectureFlags(std::string& flags) const;
   void AddCUDAToolkitFlags(std::string& flags) const;
 
+  void AddISPCTargetFlags(std::string& flags) const;
+
   std::string GetFeatureSpecificLinkRuleVariable(
     std::string const& var, std::string const& lang,
     std::string const& config) const;
@@ -515,6 +537,11 @@ public:
 
   bool ComputeCompileFeatures(std::string const& config) const;
 
+  using LanguagePair = std::pair<std::string, std::string>;
+  bool ComputeCompileFeatures(
+    std::string const& config,
+    std::set<LanguagePair> const& languagePairs) const;
+
   /**
    * Trace through the source files in this target and add al source files
    * that they depend on, used by all generators
@@ -790,6 +817,16 @@ public:
 
   const std::string& GetSourcesProperty() const;
 
+  void AddISPCGeneratedHeader(std::string const& header,
+                              std::string const& config);
+  std::vector<std::string> GetGeneratedISPCHeaders(
+    std::string const& config) const;
+
+  void AddISPCGeneratedObject(std::vector<std::string>&& objs,
+                              std::string const& config);
+  std::vector<std::string> GetGeneratedISPCObjects(
+    std::string const& config) const;
+
 private:
   void AddSourceCommon(const std::string& src, bool before = false);
 
@@ -968,6 +1005,11 @@ private:
 
   std::unordered_set<std::string> UnityBatchedSourceFiles;
 
+  std::unordered_map<std::string, std::vector<std::string>>
+    ISPCGeneratedHeaders;
+  std::unordered_map<std::string, std::vector<std::string>>
+    ISPCGeneratedObjects;
+
   bool IsLinkLookupScope(std::string const& n,
                          cmLocalGenerator const*& lg) const;
 
@@ -1038,6 +1080,11 @@ private:
   bool GetRPATH(const std::string& config, const std::string& prop,
                 std::string& rpath) const;
 
+  mutable std::map<std::string, BTs<std::string>> LanguageStandardMap;
+
+  cmProp GetPropertyWithPairedLanguageSupport(std::string const& lang,
+                                              const char* suffix) const;
+
 public:
   const std::vector<const cmGeneratorTarget*>& GetLinkImplementationClosure(
     const std::string& config) const;
@@ -1054,5 +1101,3 @@ public:
                     cmGeneratorTarget const* t2) const;
   };
 };
-
-#endif
diff --git a/Source/cmGetCMakePropertyCommand.h b/Source/cmGetCMakePropertyCommand.h
index 7a6728c..3a2e702 100644
--- a/Source/cmGetCMakePropertyCommand.h
+++ b/Source/cmGetCMakePropertyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetCMakePropertyCommand_h
-#define cmGetCMakePropertyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmGetCMakePropertyCommand(std::vector<std::string> const& args,
                                cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGetDirectoryPropertyCommand.cxx b/Source/cmGetDirectoryPropertyCommand.cxx
index fa4a40b..c2098c0 100644
--- a/Source/cmGetDirectoryPropertyCommand.cxx
+++ b/Source/cmGetDirectoryPropertyCommand.cxx
@@ -86,9 +86,7 @@ bool cmGetDirectoryPropertyCommand(std::vector<std::string> const& args,
           break;
       }
     }
-    if (cmProp p = dir->GetProperty(*i)) {
-      prop = p->c_str();
-    }
+    prop = cmToCStr(dir->GetProperty(*i));
   }
   StoreResult(status.GetMakefile(), variable, prop);
   return true;
diff --git a/Source/cmGetDirectoryPropertyCommand.h b/Source/cmGetDirectoryPropertyCommand.h
index f356ea5..4b0883c 100644
--- a/Source/cmGetDirectoryPropertyCommand.h
+++ b/Source/cmGetDirectoryPropertyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetDirectoryPropertyCommand_h
-#define cmGetDirectoryPropertyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmGetDirectoryPropertyCommand(std::vector<std::string> const& args,
                                    cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGetFilenameComponentCommand.cxx b/Source/cmGetFilenameComponentCommand.cxx
index 811421a..40e8a05 100644
--- a/Source/cmGetFilenameComponentCommand.cxx
+++ b/Source/cmGetFilenameComponentCommand.cxx
@@ -4,6 +4,7 @@
 
 #include "cmExecutionStatus.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -14,14 +15,15 @@ bool cmGetFilenameComponentCommand(std::vector<std::string> const& args,
 {
   if (args.size() < 3) {
     status.SetError("called with incorrect number of arguments");
+    cmSystemTools::SetFatalErrorOccured();
     return false;
   }
 
   // Check and see if the value has been stored in the cache
   // already, if so use that value
   if (args.size() >= 4 && args.back() == "CACHE") {
-    const char* cacheValue = status.GetMakefile().GetDefinition(args.front());
-    if (cacheValue && !cmIsNOTFOUND(cacheValue)) {
+    cmProp cacheValue = status.GetMakefile().GetDefinition(args.front());
+    if (cacheValue && !cmIsNOTFOUND(*cacheValue)) {
       return true;
     }
   }
@@ -114,6 +116,7 @@ bool cmGetFilenameComponentCommand(std::vector<std::string> const& args,
   } else {
     std::string err = "unknown component " + args[2];
     status.SetError(err);
+    cmSystemTools::SetFatalErrorOccured();
     return false;
   }
 
diff --git a/Source/cmGetFilenameComponentCommand.h b/Source/cmGetFilenameComponentCommand.h
index db5293b..4e1addf 100644
--- a/Source/cmGetFilenameComponentCommand.h
+++ b/Source/cmGetFilenameComponentCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetFilenameComponentCommand_h
-#define cmGetFilenameComponentCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -18,5 +17,3 @@ class cmExecutionStatus;
  */
 bool cmGetFilenameComponentCommand(std::vector<std::string> const& args,
                                    cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGetPipes.h b/Source/cmGetPipes.h
index 2a46b51..6b1b495 100644
--- a/Source/cmGetPipes.h
+++ b/Source/cmGetPipes.h
@@ -1,8 +1,5 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetPipes_h
-#define cmGetPipes_h
+#pragma once
 
 int cmGetPipes(int* fds);
-
-#endif
diff --git a/Source/cmGetPropertyCommand.cxx b/Source/cmGetPropertyCommand.cxx
index cba7704..3a5b39d 100644
--- a/Source/cmGetPropertyCommand.cxx
+++ b/Source/cmGetPropertyCommand.cxx
@@ -17,7 +17,6 @@
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 #include "cmTarget.h"
-#include "cmTargetPropertyComputer.h"
 #include "cmTest.h"
 #include "cmake.h"
 
@@ -282,8 +281,7 @@ bool HandleGlobalMode(cmExecutionStatus& status, const std::string& name,
   // Get the property.
   cmake* cm = status.GetMakefile().GetCMakeInstance();
   cmProp p = cm->GetState()->GetGlobalProperty(propertyName);
-  return StoreResult(infoType, status.GetMakefile(), variable,
-                     p ? p->c_str() : nullptr);
+  return StoreResult(infoType, status.GetMakefile(), variable, cmToCStr(p));
 }
 
 bool HandleDirectoryMode(cmExecutionStatus& status, const std::string& name,
@@ -330,8 +328,7 @@ bool HandleDirectoryMode(cmExecutionStatus& status, const std::string& name,
 
   // Get the property.
   cmProp p = mf->GetProperty(propertyName);
-  return StoreResult(infoType, status.GetMakefile(), variable,
-                     p ? p->c_str() : nullptr);
+  return StoreResult(infoType, status.GetMakefile(), variable, cmToCStr(p));
 }
 
 bool HandleTargetMode(cmExecutionStatus& status, const std::string& name,
@@ -364,12 +361,9 @@ bool HandleTargetMode(cmExecutionStatus& status, const std::string& name,
     cmProp prop_cstr = nullptr;
     cmListFileBacktrace bt = status.GetMakefile().GetBacktrace();
     cmMessenger* messenger = status.GetMakefile().GetMessenger();
-    if (cmTargetPropertyComputer::PassesWhitelist(
-          target->GetType(), propertyName, messenger, bt)) {
-      prop_cstr = target->GetComputedProperty(propertyName, messenger, bt);
-      if (!prop_cstr) {
-        prop_cstr = target->GetProperty(propertyName);
-      }
+    prop_cstr = target->GetComputedProperty(propertyName, messenger, bt);
+    if (!prop_cstr) {
+      prop_cstr = target->GetProperty(propertyName);
     }
     return StoreResult(infoType, status.GetMakefile(), variable,
                        prop_cstr ? prop_cstr->c_str() : nullptr);
@@ -434,8 +428,9 @@ bool HandleVariableMode(cmExecutionStatus& status, const std::string& name,
     return false;
   }
 
-  return StoreResult(infoType, status.GetMakefile(), variable,
-                     status.GetMakefile().GetDefinition(propertyName));
+  return StoreResult(
+    infoType, status.GetMakefile(), variable,
+    cmToCStr(status.GetMakefile().GetDefinition(propertyName)));
 }
 
 bool HandleCacheMode(cmExecutionStatus& status, const std::string& name,
@@ -452,8 +447,7 @@ bool HandleCacheMode(cmExecutionStatus& status, const std::string& name,
     value = status.GetMakefile().GetState()->GetCacheEntryProperty(
       name, propertyName);
   }
-  StoreResult(infoType, status.GetMakefile(), variable,
-              value ? value->c_str() : nullptr);
+  StoreResult(infoType, status.GetMakefile(), variable, cmToCStr(value));
   return true;
 }
 
diff --git a/Source/cmGetPropertyCommand.h b/Source/cmGetPropertyCommand.h
index cc600f4..fac3202 100644
--- a/Source/cmGetPropertyCommand.h
+++ b/Source/cmGetPropertyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetPropertyCommand_h
-#define cmGetPropertyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmGetPropertyCommand(std::vector<std::string> const& args,
                           cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGetSourceFilePropertyCommand.h b/Source/cmGetSourceFilePropertyCommand.h
index f0c319b..4f8eab2 100644
--- a/Source/cmGetSourceFilePropertyCommand.h
+++ b/Source/cmGetSourceFilePropertyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetSourceFilePropertyCommand_h
-#define cmGetSourceFilePropertyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmGetSourceFilePropertyCommand(std::vector<std::string> const& args,
                                     cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGetTargetPropertyCommand.cxx b/Source/cmGetTargetPropertyCommand.cxx
index 8a304be..78a17d2 100644
--- a/Source/cmGetTargetPropertyCommand.cxx
+++ b/Source/cmGetTargetPropertyCommand.cxx
@@ -12,7 +12,6 @@
 #include "cmPolicies.h"
 #include "cmProperty.h"
 #include "cmTarget.h"
-#include "cmTargetPropertyComputer.h"
 
 class cmMessenger;
 
@@ -46,12 +45,9 @@ bool cmGetTargetPropertyCommand(std::vector<std::string> const& args,
       cmProp prop_cstr = nullptr;
       cmListFileBacktrace bt = mf.GetBacktrace();
       cmMessenger* messenger = mf.GetMessenger();
-      if (cmTargetPropertyComputer::PassesWhitelist(tgt->GetType(), args[2],
-                                                    messenger, bt)) {
-        prop_cstr = tgt->GetComputedProperty(args[2], messenger, bt);
-        if (!prop_cstr) {
-          prop_cstr = tgt->GetProperty(args[2]);
-        }
+      prop_cstr = tgt->GetComputedProperty(args[2], messenger, bt);
+      if (!prop_cstr) {
+        prop_cstr = tgt->GetProperty(args[2]);
       }
       if (prop_cstr) {
         prop = *prop_cstr;
diff --git a/Source/cmGetTargetPropertyCommand.h b/Source/cmGetTargetPropertyCommand.h
index c13078f..0fbd23d 100644
--- a/Source/cmGetTargetPropertyCommand.h
+++ b/Source/cmGetTargetPropertyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetTargetPropertyCommand_h
-#define cmGetTargetPropertyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmGetTargetPropertyCommand(std::vector<std::string> const& args,
                                 cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGetTestPropertyCommand.h b/Source/cmGetTestPropertyCommand.h
index 30beb8f..f1d6010 100644
--- a/Source/cmGetTestPropertyCommand.h
+++ b/Source/cmGetTestPropertyCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGetTestPropertyCommand_h
-#define cmGetTestPropertyCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmGetTestPropertyCommand(std::vector<std::string> const& args,
                               cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmGhsMultiGpj.h b/Source/cmGhsMultiGpj.h
index fbbef5d..1cae660 100644
--- a/Source/cmGhsMultiGpj.h
+++ b/Source/cmGhsMultiGpj.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGhsMultiGpj_h
-#define cmGhsMultiGpj_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -25,5 +24,3 @@ public:
 
   static const char* GetGpjTag(Types gpjType);
 };
-
-#endif // ! cmGhsMultiGpjType_h
diff --git a/Source/cmGhsMultiTargetGenerator.cxx b/Source/cmGhsMultiTargetGenerator.cxx
index 97580d6..a8f8f57 100644
--- a/Source/cmGhsMultiTargetGenerator.cxx
+++ b/Source/cmGhsMultiTargetGenerator.cxx
@@ -43,9 +43,9 @@ cmGhsMultiTargetGenerator::cmGhsMultiTargetGenerator(cmGeneratorTarget* target)
 #endif
 {
   // Store the configuration name that is being used
-  if (const char* config = this->Makefile->GetDefinition("CMAKE_BUILD_TYPE")) {
+  if (cmProp config = this->Makefile->GetDefinition("CMAKE_BUILD_TYPE")) {
     // Use the build type given by the user.
-    this->ConfigName = config;
+    this->ConfigName = *config;
   } else {
     // No configuration type given.
     this->ConfigName.clear();
@@ -550,10 +550,9 @@ void cmGhsMultiTargetGenerator::WriteSources(std::ostream& fout_proj)
    */
   for (auto& sg : groupFilesList) {
     std::ostream* fout;
-    cmProp noSourceGroupFile =
-      this->GeneratorTarget->GetProperty("GHS_NO_SOURCE_GROUP_FILE");
-    bool useProjectFile = (noSourceGroupFile && cmIsOn(*noSourceGroupFile)) ||
-      cmIsOn(this->Makefile->GetDefinition("CMAKE_GHS_NO_SOURCE_GROUP_FILE"));
+    bool useProjectFile =
+      cmIsOn(this->GeneratorTarget->GetProperty("GHS_NO_SOURCE_GROUP_FILE")) ||
+      this->Makefile->IsOn("CMAKE_GHS_NO_SOURCE_GROUP_FILE");
     if (useProjectFile || sg.empty()) {
       fout = &fout_proj;
     } else {
diff --git a/Source/cmGhsMultiTargetGenerator.h b/Source/cmGhsMultiTargetGenerator.h
index f03ca44..e9d7537 100644
--- a/Source/cmGhsMultiTargetGenerator.h
+++ b/Source/cmGhsMultiTargetGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGhsMultiTargetGenerator_h
-#define cmGhsMultiTargetGenerator_h
+#pragma once
 
 #include <iosfwd>
 #include <map>
@@ -43,7 +42,7 @@ private:
   void SetCompilerFlags(std::string const& config,
                         const std::string& language);
 
-  std::string GetDefines(const std::string& langugae,
+  std::string GetDefines(const std::string& language,
                          std::string const& config);
 
   void WriteIncludes(std::ostream& fout, const std::string& config,
@@ -82,5 +81,3 @@ private:
   std::string ConfigName;     /* CMAKE_BUILD_TYPE */
   bool const CmdWindowsShell; /* custom commands run in cmd.exe or /bin/sh */
 };
-
-#endif // ! cmGhsMultiTargetGenerator_h
diff --git a/Source/cmGlobVerificationManager.h b/Source/cmGlobVerificationManager.h
index 2e7e1ca..b618fb0 100644
--- a/Source/cmGlobVerificationManager.h
+++ b/Source/cmGlobVerificationManager.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobVerificationManager_h
-#define cmGlobVerificationManager_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -81,5 +80,3 @@ private:
   // cmGlobVerificationManager should never be used directly.
   friend class cmState; // allow access to add cache values
 };
-
-#endif
diff --git a/Source/cmGlobalBorlandMakefileGenerator.h b/Source/cmGlobalBorlandMakefileGenerator.h
index 3c97955..5a4e8c2 100644
--- a/Source/cmGlobalBorlandMakefileGenerator.h
+++ b/Source/cmGlobalBorlandMakefileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalBorlandMakefileGenerator_h
-#define cmGlobalBorlandMakefileGenerator_h
+#pragma once
 
 #include <iosfwd>
 #include <memory>
@@ -58,5 +57,3 @@ protected:
 
   void PrintBuildCommandAdvice(std::ostream& os, int jobs) const override;
 };
-
-#endif
diff --git a/Source/cmGlobalCommonGenerator.cxx b/Source/cmGlobalCommonGenerator.cxx
index 9dc86f4..9e5bbca 100644
--- a/Source/cmGlobalCommonGenerator.cxx
+++ b/Source/cmGlobalCommonGenerator.cxx
@@ -5,8 +5,12 @@
 #include <memory>
 #include <utility>
 
+#include <cmext/algorithm>
+
+#include "cmGeneratorExpression.h"
 #include "cmGeneratorTarget.h"
 #include "cmLocalGenerator.h"
+#include "cmMakefile.h"
 #include "cmProperty.h"
 #include "cmStateDirectory.h"
 #include "cmStateSnapshot.h"
@@ -31,26 +35,30 @@ cmGlobalCommonGenerator::ComputeDirectoryTargets() const
       lg->GetStateSnapshot().GetDirectory().GetCurrentBinary());
     DirectoryTarget& dirTarget = dirTargets[currentBinaryDir];
     dirTarget.LG = lg.get();
+    const std::vector<std::string>& configs =
+      lg->GetMakefile()->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
     // The directory-level rule should depend on the target-level rules
     // for all targets in the directory.
     for (const auto& gt : lg->GetGeneratorTargets()) {
       cmStateEnums::TargetType const type = gt->GetType();
-      if (type != cmStateEnums::EXECUTABLE &&
-          type != cmStateEnums::STATIC_LIBRARY &&
-          type != cmStateEnums::SHARED_LIBRARY &&
-          type != cmStateEnums::MODULE_LIBRARY &&
-          type != cmStateEnums::OBJECT_LIBRARY &&
-          type != cmStateEnums::UTILITY) {
+      if (type == cmStateEnums::GLOBAL_TARGET || !gt->IsInBuildSystem()) {
         continue;
       }
       DirectoryTarget::Target t;
       t.GT = gt.get();
-      if (cmProp exclude = gt->GetProperty("EXCLUDE_FROM_ALL")) {
-        if (cmIsOn(*exclude)) {
-          // This target has been explicitly excluded.
-          t.ExcludeFromAll = true;
-        } else {
+      const std::string EXCLUDE_FROM_ALL("EXCLUDE_FROM_ALL");
+      if (cmProp exclude = gt->GetProperty(EXCLUDE_FROM_ALL)) {
+        for (const std::string& config : configs) {
+          cmGeneratorExpressionInterpreter genexInterpreter(lg.get(), config,
+                                                            gt.get());
+          if (cmIsOn(genexInterpreter.Evaluate(*exclude, EXCLUDE_FROM_ALL))) {
+            // This target has been explicitly excluded.
+            t.ExcludedFromAllInConfigs.push_back(config);
+          }
+        }
+
+        if (t.ExcludedFromAllInConfigs.empty()) {
           // This target has been explicitly un-excluded.  The directory-level
           // rule for every directory between this and the root should depend
           // on the target-level rule for this target.
@@ -78,3 +86,12 @@ cmGlobalCommonGenerator::ComputeDirectoryTargets() const
 
   return dirTargets;
 }
+
+bool cmGlobalCommonGenerator::IsExcludedFromAllInConfig(
+  const DirectoryTarget::Target& t, const std::string& config)
+{
+  if (this->IsMultiConfig()) {
+    return cm::contains(t.ExcludedFromAllInConfigs, config);
+  }
+  return !t.ExcludedFromAllInConfigs.empty();
+}
diff --git a/Source/cmGlobalCommonGenerator.h b/Source/cmGlobalCommonGenerator.h
index 7d16dac..2aa9d27 100644
--- a/Source/cmGlobalCommonGenerator.h
+++ b/Source/cmGlobalCommonGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalCommonGenerator_h
-#define cmGlobalCommonGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -30,7 +29,7 @@ public:
     struct Target
     {
       cmGeneratorTarget const* GT = nullptr;
-      bool ExcludeFromAll = false;
+      std::vector<std::string> ExcludedFromAllInConfigs;
     };
     std::vector<Target> Targets;
     struct Dir
@@ -41,6 +40,6 @@ public:
     std::vector<Dir> Children;
   };
   std::map<std::string, DirectoryTarget> ComputeDirectoryTargets() const;
+  bool IsExcludedFromAllInConfig(const DirectoryTarget::Target& t,
+                                 const std::string& config);
 };
-
-#endif
diff --git a/Source/cmGlobalGenerator.cxx b/Source/cmGlobalGenerator.cxx
index 4dc4092..8688b1b 100644
--- a/Source/cmGlobalGenerator.cxx
+++ b/Source/cmGlobalGenerator.cxx
@@ -235,6 +235,14 @@ void cmGlobalGenerator::ResolveLanguageCompiler(const std::string& lang,
   }
   cmProp cname =
     this->GetCMakeInstance()->GetState()->GetInitializedCacheValue(langComp);
+
+  // Split compiler from arguments
+  std::vector<std::string> cnameArgVec;
+  if (cname && !cname->empty()) {
+    cmExpandList(*cname, cnameArgVec);
+    cname = &cnameArgVec.front();
+  }
+
   std::string changeVars;
   if (cname && !optional) {
     std::string cnameString;
@@ -302,31 +310,12 @@ bool cmGlobalGenerator::CheckTargetsForMissingSources() const
   bool failed = false;
   for (const auto& localGen : this->LocalGenerators) {
     for (const auto& target : localGen->GetGeneratorTargets()) {
-      if (target->GetType() == cmStateEnums::TargetType::GLOBAL_TARGET ||
-          target->GetType() == cmStateEnums::TargetType::INTERFACE_LIBRARY ||
-          target->GetType() == cmStateEnums::TargetType::UTILITY) {
+      if (!target->CanCompileSources() ||
+          cmIsOn(target->GetProperty("ghs_integrity_app"))) {
         continue;
       }
-      if (cmProp p = target->GetProperty("ghs_integrity_app")) {
-        if (cmIsOn(*p)) {
-          continue;
-        }
-      }
 
-      std::vector<std::string> configs;
-      target->Makefile->GetConfigurations(configs);
-      std::vector<cmSourceFile*> srcs;
-      if (configs.empty()) {
-        target->GetSourceFiles(srcs, "");
-      } else {
-        for (std::string const& config : configs) {
-          target->GetSourceFiles(srcs, config);
-          if (!srcs.empty()) {
-            break;
-          }
-        }
-      }
-      if (srcs.empty()) {
+      if (target->GetAllConfigSources().empty()) {
         std::ostringstream e;
         e << "No SOURCES given to target: " << target->GetName();
         this->GetCMakeInstance()->IssueMessage(
@@ -346,12 +335,13 @@ bool cmGlobalGenerator::CheckTargetsForType() const
   bool failed = false;
   for (const auto& generator : this->LocalGenerators) {
     for (const auto& target : generator->GetGeneratorTargets()) {
-      if (target->GetType() == cmStateEnums::EXECUTABLE &&
-          target->GetPropertyAsBool("WIN32_EXECUTABLE")) {
+      if (target->GetType() == cmStateEnums::EXECUTABLE) {
         std::vector<std::string> const& configs =
-          target->Makefile->GetGeneratorConfigs();
+          target->Makefile->GetGeneratorConfigs(
+            cmMakefile::IncludeEmptyConfig);
         for (std::string const& config : configs) {
-          if (target->GetLinkerLanguage(config) == "Swift") {
+          if (target->IsWin32Executable(config) &&
+              target->GetLinkerLanguage(config) == "Swift") {
             this->GetCMakeInstance()->IssueMessage(
               MessageType::FATAL_ERROR,
               "WIN32_EXECUTABLE property is not supported on Swift "
@@ -374,16 +364,10 @@ bool cmGlobalGenerator::CheckTargetsForPchCompilePdb() const
   bool failed = false;
   for (const auto& generator : this->LocalGenerators) {
     for (const auto& target : generator->GetGeneratorTargets()) {
-      if (target->GetType() == cmStateEnums::TargetType::GLOBAL_TARGET ||
-          target->GetType() == cmStateEnums::TargetType::INTERFACE_LIBRARY ||
-          target->GetType() == cmStateEnums::TargetType::UTILITY) {
+      if (!target->CanCompileSources() ||
+          cmIsOn(target->GetProperty("ghs_integrity_app"))) {
         continue;
       }
-      if (cmProp p = target->GetProperty("ghs_integrity_app")) {
-        if (cmIsOn(*p)) {
-          continue;
-        }
-      }
 
       std::string const& reuseFrom =
         target->GetSafeProperty("PRECOMPILE_HEADERS_REUSE_FROM");
@@ -425,15 +409,13 @@ bool cmGlobalGenerator::FindMakeProgram(cmMakefile* mf)
       "all generators must specify this->FindMakeProgramFile");
     return false;
   }
-  if (!mf->GetDefinition("CMAKE_MAKE_PROGRAM") ||
-      cmIsOff(mf->GetDefinition("CMAKE_MAKE_PROGRAM"))) {
+  if (cmIsOff(mf->GetDefinition("CMAKE_MAKE_PROGRAM"))) {
     std::string setMakeProgram = mf->GetModulesFile(this->FindMakeProgramFile);
     if (!setMakeProgram.empty()) {
       mf->ReadListFile(setMakeProgram);
     }
   }
-  if (!mf->GetDefinition("CMAKE_MAKE_PROGRAM") ||
-      cmIsOff(mf->GetDefinition("CMAKE_MAKE_PROGRAM"))) {
+  if (cmIsOff(mf->GetDefinition("CMAKE_MAKE_PROGRAM"))) {
     std::ostringstream err;
     err << "CMake was unable to find a build program corresponding to \""
         << this->GetName() << "\".  CMAKE_MAKE_PROGRAM is not set.  You "
@@ -596,6 +578,16 @@ void cmGlobalGenerator::EnableLanguage(
       mf->ReadListFile(fpath);
     }
   }
+
+  if (readCMakeSystem) {
+    // Find the native build tool for this generator.
+    // This has to be done early so that MSBuild can be used to examine the
+    // cross-compilation environment.
+    if (!this->FindMakeProgram(mf)) {
+      return;
+    }
+  }
+
   //  Load the CMakeDetermineSystem.cmake file and find out
   // what platform we are running on
   if (!mf->GetDefinition("CMAKE_SYSTEM")) {
@@ -667,11 +659,6 @@ void cmGlobalGenerator::EnableLanguage(
       cmSystemTools::SetFatalErrorOccured();
       return;
     }
-
-    // Find the native build tool for this generator.
-    if (!this->FindMakeProgram(mf)) {
-      return;
-    }
   }
 
   // Check that the languages are supported by the generator and its
@@ -793,27 +780,27 @@ void cmGlobalGenerator::EnableLanguage(
     std::string compilerName = cmStrCat("CMAKE_", lang, "_COMPILER");
     std::string compilerEnv = cmStrCat("CMAKE_", lang, "_COMPILER_ENV_VAR");
     std::ostringstream noCompiler;
-    const char* compilerFile = mf->GetDefinition(compilerName);
-    if (!compilerFile || !*compilerFile || cmIsNOTFOUND(compilerFile)) {
+    cmProp compilerFile = mf->GetDefinition(compilerName);
+    if (!cmNonempty(compilerFile) || cmIsNOTFOUND(*compilerFile)) {
       /* clang-format off */
       noCompiler <<
         "No " << compilerName << " could be found.\n"
         ;
       /* clang-format on */
     } else if ((lang != "RC") && (lang != "ASM_MASM")) {
-      if (!cmSystemTools::FileIsFullPath(compilerFile)) {
+      if (!cmSystemTools::FileIsFullPath(*compilerFile)) {
         /* clang-format off */
         noCompiler <<
           "The " << compilerName << ":\n"
-          "  " << compilerFile << "\n"
+          "  " << *compilerFile << "\n"
           "is not a full path and was not found in the PATH.\n"
           ;
         /* clang-format on */
-      } else if (!cmSystemTools::FileExists(compilerFile)) {
+      } else if (!cmSystemTools::FileExists(*compilerFile)) {
         /* clang-format off */
         noCompiler <<
           "The " << compilerName << ":\n"
-          "  " << compilerFile << "\n"
+          "  " << *compilerFile << "\n"
           "is not a full path to an existing compiler tool.\n"
           ;
         /* clang-format on */
@@ -830,7 +817,7 @@ void cmGlobalGenerator::EnableLanguage(
         cmSystemTools::RemoveFile(compilerLangFile);
         if (!this->CMakeInstance->GetIsInTryCompile()) {
           this->PrintCompilerAdvice(noCompiler, lang,
-                                    mf->GetDefinition(compilerEnv));
+                                    cmToCStr(mf->GetDefinition(compilerEnv)));
           mf->IssueMessage(MessageType::FATAL_ERROR, noCompiler.str());
           fatalError = true;
         }
@@ -1108,17 +1095,16 @@ void cmGlobalGenerator::SetLanguageEnabledMaps(const std::string& l,
     return;
   }
 
-  std::string linkerPrefVar =
-    std::string("CMAKE_") + std::string(l) + std::string("_LINKER_PREFERENCE");
-  const char* linkerPref = mf->GetDefinition(linkerPrefVar);
+  std::string linkerPrefVar = "CMAKE_" + l + "_LINKER_PREFERENCE";
+  cmProp linkerPref = mf->GetDefinition(linkerPrefVar);
   int preference = 0;
-  if (linkerPref) {
-    if (sscanf(linkerPref, "%d", &preference) != 1) {
+  if (cmNonempty(linkerPref)) {
+    if (sscanf(linkerPref->c_str(), "%d", &preference) != 1) {
       // backward compatibility: before 2.6 LINKER_PREFERENCE
       // was either "None" or "Preferred", and only the first character was
       // tested. So if there is a custom language out there and it is
       // "Preferred", set its preference high
-      if (linkerPref[0] == 'P') {
+      if ((*linkerPref)[0] == 'P') {
         preference = 100;
       } else {
         preference = 0;
@@ -1135,14 +1121,14 @@ void cmGlobalGenerator::SetLanguageEnabledMaps(const std::string& l,
 
   this->LanguageToLinkerPreference[l] = preference;
 
-  std::string outputExtensionVar =
-    std::string("CMAKE_") + std::string(l) + std::string("_OUTPUT_EXTENSION");
-  const char* outputExtension = mf->GetDefinition(outputExtensionVar);
-  if (outputExtension) {
+  std::string outputExtensionVar = "CMAKE_" + l + "_OUTPUT_EXTENSION";
+  if (cmProp p = mf->GetDefinition(outputExtensionVar)) {
+    std::string outputExtension = *p;
     this->LanguageToOutputExtension[l] = outputExtension;
     this->OutputExtensions[outputExtension] = outputExtension;
-    if (outputExtension[0] == '.') {
-      this->OutputExtensions[outputExtension + 1] = outputExtension + 1;
+    if (cmHasPrefix(outputExtension, ".")) {
+      outputExtension = outputExtension.substr(1);
+      this->OutputExtensions[outputExtension] = outputExtension;
     }
   }
 
@@ -1175,7 +1161,7 @@ void cmGlobalGenerator::FillExtensionToLanguageMap(const std::string& l,
 const char* cmGlobalGenerator::GetGlobalSetting(std::string const& name) const
 {
   assert(!this->Makefiles.empty());
-  return this->Makefiles[0]->GetDefinition(name);
+  return cmToCStr(this->Makefiles[0]->GetDefinition(name));
 }
 
 bool cmGlobalGenerator::GlobalSettingIsOn(std::string const& name) const
@@ -1442,12 +1428,10 @@ bool cmGlobalGenerator::Compute()
     localGen->AddHelperCommands();
   }
 
-  // Finalize the set of compile features for each target.
-  // FIXME: This turns into calls to cmMakefile::AddRequiredTargetFeature
-  // which actually modifies the <lang>_STANDARD target property
-  // on the original cmTarget instance.  It accumulates features
-  // across all configurations.  Some refactoring is needed to
-  // compute a per-config resulta purely during generation.
+  // Perform up-front computation in order to handle errors (such as unknown
+  // features) at this point. While processing the compile features we also
+  // calculate and cache the language standard required by the compile
+  // features.
   for (const auto& localGen : this->LocalGenerators) {
     if (!localGen->ComputeTargetCompileFeatures()) {
       return false;
@@ -1487,6 +1471,7 @@ bool cmGlobalGenerator::Compute()
   if (!this->ComputeTargetDepends()) {
     return false;
   }
+  this->ComputeTargetOrder();
 
   if (this->CheckTargetsForType()) {
     return false;
@@ -1597,6 +1582,50 @@ bool cmGlobalGenerator::ComputeTargetDepends()
   return true;
 }
 
+std::vector<cmGeneratorTarget*>
+cmGlobalGenerator::GetLocalGeneratorTargetsInOrder(cmLocalGenerator* lg) const
+{
+  std::vector<cmGeneratorTarget*> gts;
+  cm::append(gts, lg->GetGeneratorTargets());
+  std::sort(gts.begin(), gts.end(),
+            [this](cmGeneratorTarget const* l, cmGeneratorTarget const* r) {
+              return this->TargetOrderIndex.at(l) <
+                this->TargetOrderIndex.at(r);
+            });
+  return gts;
+}
+
+void cmGlobalGenerator::ComputeTargetOrder()
+{
+  size_t index = 0;
+  auto const& lgens = this->GetLocalGenerators();
+  for (auto const& lgen : lgens) {
+    const auto& targets = lgen->GetGeneratorTargets();
+    for (const auto& gt : targets) {
+      this->ComputeTargetOrder(gt.get(), index);
+    }
+  }
+  assert(index == this->TargetOrderIndex.size());
+}
+
+void cmGlobalGenerator::ComputeTargetOrder(cmGeneratorTarget const* gt,
+                                           size_t& index)
+{
+  std::map<cmGeneratorTarget const*, size_t>::value_type value(gt, 0);
+  auto insertion = this->TargetOrderIndex.insert(value);
+  if (!insertion.second) {
+    return;
+  }
+  auto entry = insertion.first;
+
+  auto& deps = this->GetTargetDirectDepends(gt);
+  for (auto& d : deps) {
+    this->ComputeTargetOrder(d, index);
+  }
+
+  entry->second = index++;
+}
+
 bool cmGlobalGenerator::QtAutoGen()
 {
 #ifndef CMAKE_BOOTSTRAP
@@ -1612,12 +1641,11 @@ bool cmGlobalGenerator::AddAutomaticSources()
   for (const auto& lg : this->LocalGenerators) {
     lg->CreateEvaluationFileOutputs();
     for (const auto& gt : lg->GetGeneratorTargets()) {
-      if (gt->GetType() == cmStateEnums::INTERFACE_LIBRARY ||
-          gt->GetType() == cmStateEnums::UTILITY ||
-          gt->GetType() == cmStateEnums::GLOBAL_TARGET) {
+      if (!gt->CanCompileSources()) {
         continue;
       }
       lg->AddUnityBuild(gt.get());
+      lg->AddISPCDependencies(gt.get());
       // Targets that re-use a PCH are handled below.
       if (!gt->GetProperty("PRECOMPILE_HEADERS_REUSE_FROM")) {
         lg->AddPchDependencies(gt.get());
@@ -1626,9 +1654,7 @@ bool cmGlobalGenerator::AddAutomaticSources()
   }
   for (const auto& lg : this->LocalGenerators) {
     for (const auto& gt : lg->GetGeneratorTargets()) {
-      if (gt->GetType() == cmStateEnums::INTERFACE_LIBRARY ||
-          gt->GetType() == cmStateEnums::UTILITY ||
-          gt->GetType() == cmStateEnums::GLOBAL_TARGET) {
+      if (!gt->CanCompileSources()) {
         continue;
       }
       // Handle targets that re-use a PCH from an above-handled target.
@@ -1698,8 +1724,8 @@ void cmGlobalGenerator::FinalizeTargetCompileInfo()
       cmPolicies::PolicyStatus polSt =
         mf->GetPolicyStatus(cmPolicies::CMP0043);
       if (polSt == cmPolicies::WARN || polSt == cmPolicies::OLD) {
-        std::vector<std::string> configs;
-        mf->GetConfigurations(configs);
+        std::vector<std::string> configs =
+          mf->GetGeneratorConfigs(cmMakefile::ExcludeEmptyConfig);
 
         for (std::string const& c : configs) {
           std::string defPropName =
@@ -1779,6 +1805,7 @@ void cmGlobalGenerator::ClearGeneratorMembers()
   this->GeneratorTargetSearchIndex.clear();
   this->MakefileSearchIndex.clear();
   this->LocalGeneratorSearchIndex.clear();
+  this->TargetOrderIndex.clear();
   this->ProjectMap.clear();
   this->RuleHashes.clear();
   this->DirectoryContentMap.clear();
@@ -1988,8 +2015,9 @@ int cmGlobalGenerator::Build(
   std::string makeCommandStr;
   output += "\nRun Build Command(s):";
 
-  for (auto command = makeCommand.begin(); command != makeCommand.end();
-       ++command) {
+  retVal = 0;
+  for (auto command = makeCommand.begin();
+       command != makeCommand.end() && retVal == 0; ++command) {
     makeCommandStr = command->Printable();
     if (command != makeCommand.end()) {
       makeCommandStr += " && ";
@@ -2179,13 +2207,38 @@ bool cmGlobalGenerator::IsExcluded(cmLocalGenerator* root,
 }
 
 bool cmGlobalGenerator::IsExcluded(cmLocalGenerator* root,
-                                   cmGeneratorTarget* target) const
+                                   const cmGeneratorTarget* target) const
 {
-  if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+  if (!target->IsInBuildSystem()) {
     return true;
   }
-  if (cmProp exclude = target->GetProperty("EXCLUDE_FROM_ALL")) {
-    return cmIsOn(*exclude);
+  cmMakefile* mf = root->GetMakefile();
+  const std::string EXCLUDE_FROM_ALL = "EXCLUDE_FROM_ALL";
+  if (cmProp exclude = target->GetProperty(EXCLUDE_FROM_ALL)) {
+    // Expand the property value per configuration.
+    unsigned int trueCount = 0;
+    unsigned int falseCount = 0;
+    const std::vector<std::string>& configs =
+      mf->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
+    for (const std::string& config : configs) {
+      cmGeneratorExpressionInterpreter genexInterpreter(root, config, target);
+      if (cmIsOn(genexInterpreter.Evaluate(*exclude, EXCLUDE_FROM_ALL))) {
+        ++trueCount;
+      } else {
+        ++falseCount;
+      }
+    }
+
+    // Check whether the genex expansion of the property agrees in all
+    // configurations.
+    if (trueCount && falseCount) {
+      std::ostringstream e;
+      e << "The EXCLUDE_FROM_ALL property of target \"" << target->GetName()
+        << "\" varies by configuration. This is not supported by the \""
+        << root->GetGlobalGenerator()->GetName() << "\" generator.";
+      mf->IssueMessage(MessageType::FATAL_ERROR, e.str());
+    }
+    return trueCount;
   }
   // This target is included in its directory.  Check whether the
   // directory is excluded.
@@ -2445,7 +2498,7 @@ void cmGlobalGenerator::AddGlobalTarget_Package(
   gti.WorkingDir = mf->GetCurrentBinaryDirectory();
   cmCustomCommandLine singleLine;
   singleLine.push_back(cmSystemTools::GetCPackCommand());
-  if (cmakeCfgIntDir && *cmakeCfgIntDir && cmakeCfgIntDir[0] != '.') {
+  if (cmNonempty(cmakeCfgIntDir) && cmakeCfgIntDir[0] != '.') {
     singleLine.push_back("-C");
     singleLine.push_back(cmakeCfgIntDir);
   }
@@ -2455,9 +2508,9 @@ void cmGlobalGenerator::AddGlobalTarget_Package(
   if (this->GetPreinstallTargetName()) {
     gti.Depends.emplace_back(this->GetPreinstallTargetName());
   } else {
-    const char* noPackageAll =
+    cmProp noPackageAll =
       mf->GetDefinition("CMAKE_SKIP_PACKAGE_ALL_DEPENDENCY");
-    if (!noPackageAll || cmIsOff(noPackageAll)) {
+    if (cmIsOff(noPackageAll)) {
       gti.Depends.emplace_back(this->GetAllTargetName());
     }
   }
@@ -2530,7 +2583,7 @@ void cmGlobalGenerator::AddGlobalTarget_Test(
       singleLine.push_back(arg);
     }
   }
-  if (cmakeCfgIntDir && *cmakeCfgIntDir && cmakeCfgIntDir[0] != '.') {
+  if (cmNonempty(cmakeCfgIntDir) && cmakeCfgIntDir[0] != '.') {
     singleLine.push_back("-C");
     singleLine.push_back(cmakeCfgIntDir);
   } else // TODO: This is a hack. Should be something to do with the
@@ -2611,7 +2664,7 @@ void cmGlobalGenerator::AddGlobalTarget_Install(
       "installation rules have been specified",
       mf->GetBacktrace());
   } else if (this->InstallTargetEnabled && !skipInstallRules) {
-    if (!cmakeCfgIntDir || !*cmakeCfgIntDir || cmakeCfgIntDir[0] == '.') {
+    if (!(cmNonempty(cmakeCfgIntDir) && cmakeCfgIntDir[0] != '.')) {
       std::set<std::string>* componentsSet = &this->InstallComponents;
       std::ostringstream ostr;
       if (!componentsSet->empty()) {
@@ -2636,9 +2689,8 @@ void cmGlobalGenerator::AddGlobalTarget_Install(
     if (this->GetPreinstallTargetName()) {
       gti.Depends.emplace_back(this->GetPreinstallTargetName());
     } else {
-      const char* noall =
-        mf->GetDefinition("CMAKE_SKIP_INSTALL_ALL_DEPENDENCY");
-      if (!noall || cmIsOff(noall)) {
+      cmProp noall = mf->GetDefinition("CMAKE_SKIP_INSTALL_ALL_DEPENDENCY");
+      if (cmIsOff(noall)) {
         gti.Depends.emplace_back(this->GetAllTargetName());
       }
     }
@@ -2650,7 +2702,7 @@ void cmGlobalGenerator::AddGlobalTarget_Install(
       cmd = "cmake";
     }
     singleLine.push_back(cmd);
-    if (cmakeCfgIntDir && *cmakeCfgIntDir && cmakeCfgIntDir[0] != '.') {
+    if (cmNonempty(cmakeCfgIntDir) && cmakeCfgIntDir[0] != '.') {
       std::string cfgArg = "-DBUILD_TYPE=";
       bool useEPN = this->UseEffectivePlatformName(mf.get());
       if (useEPN) {
@@ -2658,7 +2710,7 @@ void cmGlobalGenerator::AddGlobalTarget_Install(
         singleLine.push_back(cfgArg);
         cfgArg = "-DEFFECTIVE_PLATFORM_NAME=$(EFFECTIVE_PLATFORM_NAME)";
       } else {
-        cfgArg += mf->GetDefinition("CMAKE_CFG_INTDIR");
+        cfgArg += cmToCStr(mf->GetDefinition("CMAKE_CFG_INTDIR"));
       }
       singleLine.push_back(cfgArg);
     }
@@ -3045,7 +3097,7 @@ void cmGlobalGenerator::WriteSummary()
 
   for (const auto& lg : this->LocalGenerators) {
     for (const auto& tgt : lg->GetGeneratorTargets()) {
-      if (tgt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+      if (!tgt->IsInBuildSystem()) {
         continue;
       }
       this->WriteSummary(tgt.get());
@@ -3066,7 +3118,7 @@ void cmGlobalGenerator::WriteSummary(cmGeneratorTarget* target)
   cmProp targetLabels = target->GetProperty("LABELS");
   cmProp directoryLabels =
     target->Target->GetMakefile()->GetProperty("LABELS");
-  const char* cmakeDirectoryLabels =
+  cmProp cmakeDirectoryLabels =
     target->Target->GetMakefile()->GetDefinition("CMAKE_DIRECTORY_LABELS");
   if (targetLabels || directoryLabels || cmakeDirectoryLabels) {
     Json::Value lj_root(Json::objectValue);
@@ -3102,7 +3154,7 @@ void cmGlobalGenerator::WriteSummary(cmGeneratorTarget* target)
     }
 
     if (cmakeDirectoryLabels) {
-      cmExpandList(cmakeDirectoryLabels, cmakeDirectoryLabelsList);
+      cmExpandList(*cmakeDirectoryLabels, cmakeDirectoryLabelsList);
     }
 
     if (!directoryLabelsList.empty() || !cmakeDirectoryLabelsList.empty()) {
@@ -3123,7 +3175,8 @@ void cmGlobalGenerator::WriteSummary(cmGeneratorTarget* target)
     fout << "# Source files and their labels\n";
     std::vector<cmSourceFile*> sources;
     std::vector<std::string> const& configs =
-      target->Target->GetMakefile()->GetGeneratorConfigs();
+      target->Target->GetMakefile()->GetGeneratorConfigs(
+        cmMakefile::IncludeEmptyConfig);
     for (std::string const& c : configs) {
       target->GetSourceFiles(sources, c);
     }
@@ -3222,8 +3275,9 @@ bool cmGlobalGenerator::GenerateCPackPropertiesFile()
   const auto& lg = this->LocalGenerators[0];
   cmMakefile* mf = lg->GetMakefile();
 
-  std::vector<std::string> configs;
-  std::string config = mf->GetConfigurations(configs, false);
+  std::vector<std::string> configs =
+    mf->GetGeneratorConfigs(cmMakefile::OnlyMultiConfig);
+  std::string config = mf->GetDefaultConfiguration();
 
   std::string path = cmStrCat(this->CMakeInstance->GetHomeOutputDirectory(),
                               "/CPackProperties.cmake");
diff --git a/Source/cmGlobalGenerator.h b/Source/cmGlobalGenerator.h
index 57c7808..478028e 100644
--- a/Source/cmGlobalGenerator.h
+++ b/Source/cmGlobalGenerator.h
@@ -1,10 +1,10 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalGenerator_h
-#define cmGlobalGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
+#include <cstddef>
 #include <iosfwd>
 #include <map>
 #include <memory>
@@ -265,6 +265,9 @@ public:
     return this->LocalGenerators;
   }
 
+  std::vector<cmGeneratorTarget*> GetLocalGeneratorTargetsInOrder(
+    cmLocalGenerator* lg) const;
+
   cmMakefile* GetCurrentMakefile() const
   {
     return this->CurrentConfigureMakefile;
@@ -542,7 +545,8 @@ protected:
   bool IsExcluded(cmStateSnapshot const& root,
                   cmStateSnapshot const& snp) const;
   bool IsExcluded(cmLocalGenerator* root, cmLocalGenerator* gen) const;
-  bool IsExcluded(cmLocalGenerator* root, cmGeneratorTarget* target) const;
+  bool IsExcluded(cmLocalGenerator* root,
+                  const cmGeneratorTarget* target) const;
   virtual void InitializeProgressMarks() {}
 
   struct GlobalTargetInfo
@@ -613,6 +617,10 @@ private:
   // Its order is not deterministic.
   LocalGeneratorMap LocalGeneratorSearchIndex;
 
+  void ComputeTargetOrder();
+  void ComputeTargetOrder(cmGeneratorTarget const* gt, size_t& index);
+  std::map<cmGeneratorTarget const*, size_t> TargetOrderIndex;
+
   cmMakefile* TryCompileOuterMakefile;
   // If you add a new map here, make sure it is copied
   // in EnableLanguagesFromGenerator
@@ -716,5 +724,3 @@ protected:
   bool InstallTargetEnabled;
   bool ConfigureDoneCMP0026AndCMP0024;
 };
-
-#endif
diff --git a/Source/cmGlobalGeneratorFactory.h b/Source/cmGlobalGeneratorFactory.h
index 3709365..3a7f806 100644
--- a/Source/cmGlobalGeneratorFactory.h
+++ b/Source/cmGlobalGeneratorFactory.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalGeneratorFactory_h
-#define cmGlobalGeneratorFactory_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -44,7 +43,7 @@ public:
   /** Get the list of supported platforms name for this generator */
   virtual std::vector<std::string> GetKnownPlatforms() const = 0;
 
-  /** If the generator suports platforms, get its default.  */
+  /** If the generator supports platforms, get its default.  */
   virtual std::string GetDefaultPlatformName() const = 0;
 };
 
@@ -95,5 +94,3 @@ public:
 
   std::string GetDefaultPlatformName() const override { return std::string(); }
 };
-
-#endif
diff --git a/Source/cmGlobalGhsMultiGenerator.cxx b/Source/cmGlobalGhsMultiGenerator.cxx
index d36adfb..cbaf0ab 100644
--- a/Source/cmGlobalGhsMultiGenerator.cxx
+++ b/Source/cmGlobalGhsMultiGenerator.cxx
@@ -100,13 +100,13 @@ bool cmGlobalGhsMultiGenerator::SetGeneratorToolset(std::string const& ts,
   /* set the build tool to use */
   std::string gbuild(tsp + ((tsp.back() == '/') ? "" : "/") +
                      DEFAULT_BUILD_PROGRAM);
-  const char* prevTool = mf->GetDefinition("CMAKE_MAKE_PROGRAM");
+  cmProp prevTool = mf->GetDefinition("CMAKE_MAKE_PROGRAM");
 
   /* check if the toolset changed from last generate */
-  if (prevTool != nullptr && (gbuild != prevTool)) {
+  if (prevTool && (gbuild != *prevTool)) {
     std::string message =
       cmStrCat("toolset build tool: ", gbuild,
-               "\nDoes not match the previously used build tool: ", prevTool,
+               "\nDoes not match the previously used build tool: ", *prevTool,
                "\nEither remove the CMakeCache.txt file and CMakeFiles "
                "directory or choose a different binary directory.");
     cmSystemTools::Error(message);
@@ -187,7 +187,8 @@ void cmGlobalGhsMultiGenerator::EnableLanguage(
 
   mf->AddDefinition("GHSMULTI", "1"); // identifier for user CMake files
 
-  const char* tgtPlatform = mf->GetDefinition("GHS_TARGET_PLATFORM");
+  const char* tgtPlatform =
+    cmToCStrSafe(mf->GetDefinition("GHS_TARGET_PLATFORM"));
   if (!tgtPlatform) {
     cmSystemTools::Message("Green Hills MULTI: GHS_TARGET_PLATFORM not "
                            "specified; defaulting to \"integrity\"");
@@ -216,12 +217,13 @@ bool cmGlobalGhsMultiGenerator::FindMakeProgram(cmMakefile* /*mf*/)
 void cmGlobalGhsMultiGenerator::GetToolset(cmMakefile* mf, std::string& tsd,
                                            const std::string& ts)
 {
-  const char* ghsRoot = mf->GetDefinition("GHS_TOOLSET_ROOT");
+  cmProp ghsRoot = mf->GetDefinition("GHS_TOOLSET_ROOT");
 
-  if (!ghsRoot || ghsRoot[0] == '\0') {
-    ghsRoot = DEFAULT_TOOLSET_ROOT;
+  if (cmNonempty(ghsRoot)) {
+    tsd = *ghsRoot;
+  } else {
+    tsd = DEFAULT_TOOLSET_ROOT;
   }
-  tsd = ghsRoot;
 
   if (ts.empty()) {
     std::vector<std::string> output;
@@ -467,11 +469,10 @@ void cmGlobalGhsMultiGenerator::WriteAllTarget(
     this->ProjectTargets.push_back(t);
   }
   for (cmGeneratorTarget const* t : sortedProjectTargets) {
-    if (t->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!t->IsInBuildSystem()) {
       continue;
     }
-    cmProp p = t->GetProperty("EXCLUDE_FROM_ALL");
-    if (!(p && cmIsOn(*p))) {
+    if (!IsExcluded(t->GetLocalGenerator(), t)) {
       defaultTargets.push_back(t);
     }
   }
@@ -635,7 +636,7 @@ void cmGlobalGhsMultiGenerator::WriteHighLevelDirectives(
   std::string tgt;
   const char* t =
     this->GetCMakeInstance()->GetCacheDefinition("GHS_PRIMARY_TARGET");
-  if (t && *t != '\0') {
+  if (cmNonempty(t)) {
     tgt = t;
     this->GetCMakeInstance()->MarkCliAsUsed("GHS_PRIMARY_TARGET");
   } else {
diff --git a/Source/cmGlobalGhsMultiGenerator.h b/Source/cmGlobalGhsMultiGenerator.h
index 12ca8b6..7753b31 100644
--- a/Source/cmGlobalGhsMultiGenerator.h
+++ b/Source/cmGlobalGhsMultiGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGhsMultiGenerator_h
-#define cmGhsMultiGenerator_h
+#pragma once
 
 #include <iosfwd>
 #include <memory>
@@ -158,5 +157,3 @@ public:
   using TargetDependSet = cmGlobalGenerator::TargetDependSet;
   OrderedTargetDependSet(TargetDependSet const&, std::string const& first);
 };
-
-#endif
diff --git a/Source/cmGlobalJOMMakefileGenerator.h b/Source/cmGlobalJOMMakefileGenerator.h
index 9f1ec8b..2d58f91 100644
--- a/Source/cmGlobalJOMMakefileGenerator.h
+++ b/Source/cmGlobalJOMMakefileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalJOMMakefileGenerator_h
-#define cmGlobalJOMMakefileGenerator_h
+#pragma once
 
 #include <iosfwd>
 #include <memory>
@@ -53,5 +52,3 @@ private:
   void PrintCompilerAdvice(std::ostream& os, std::string const& lang,
                            const char* envVar) const override;
 };
-
-#endif
diff --git a/Source/cmGlobalMSYSMakefileGenerator.h b/Source/cmGlobalMSYSMakefileGenerator.h
index b2de4ff..1a47b4f 100644
--- a/Source/cmGlobalMSYSMakefileGenerator.h
+++ b/Source/cmGlobalMSYSMakefileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalMSYSMakefileGenerator_h
-#define cmGlobalMSYSMakefileGenerator_h
+#pragma once
 
 #include <memory>
 
@@ -42,5 +41,3 @@ public:
 private:
   std::string FindMinGW(std::string const& makeloc);
 };
-
-#endif
diff --git a/Source/cmGlobalMinGWMakefileGenerator.h b/Source/cmGlobalMinGWMakefileGenerator.h
index a9f92a1..ffc9ebe 100644
--- a/Source/cmGlobalMinGWMakefileGenerator.h
+++ b/Source/cmGlobalMinGWMakefileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalMinGWMakefileGenerator_h
-#define cmGlobalMinGWMakefileGenerator_h
+#pragma once
 
 #include <memory>
 
@@ -38,5 +37,3 @@ public:
   virtual void EnableLanguage(std::vector<std::string> const& languages,
                               cmMakefile*, bool optional);
 };
-
-#endif
diff --git a/Source/cmGlobalNMakeMakefileGenerator.h b/Source/cmGlobalNMakeMakefileGenerator.h
index fdf6006..abe64ff 100644
--- a/Source/cmGlobalNMakeMakefileGenerator.h
+++ b/Source/cmGlobalNMakeMakefileGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalNMakeMakefileGenerator_h
-#define cmGlobalNMakeMakefileGenerator_h
+#pragma once
 
 #include <iosfwd>
 #include <memory>
@@ -59,5 +58,3 @@ private:
   void PrintCompilerAdvice(std::ostream& os, std::string const& lang,
                            const char* envVar) const override;
 };
-
-#endif
diff --git a/Source/cmGlobalNinjaGenerator.cxx b/Source/cmGlobalNinjaGenerator.cxx
index f11cd50..006925d 100644
--- a/Source/cmGlobalNinjaGenerator.cxx
+++ b/Source/cmGlobalNinjaGenerator.cxx
@@ -5,9 +5,9 @@
 #include <algorithm>
 #include <cctype>
 #include <cstdio>
-#include <iterator>
 #include <sstream>
 
+#include <cm/iterator>
 #include <cm/memory>
 #include <cmext/algorithm>
 #include <cmext/memory>
@@ -32,6 +32,7 @@
 #include "cmMessageType.h"
 #include "cmNinjaLinkLineComputer.h"
 #include "cmOutputConverter.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmState.h"
 #include "cmStateDirectory.h"
@@ -518,7 +519,8 @@ void cmGlobalNinjaGenerator::Generate()
 
   if (cmSystemTools::GetErrorOccuredFlag()) {
     this->RulesFileStream->setstate(std::ios::failbit);
-    for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs()) {
+    for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs(
+           cmMakefile::IncludeEmptyConfig)) {
       this->GetImplFileStream(config)->setstate(std::ios::failbit);
       this->GetConfigFileStream(config)->setstate(std::ios::failbit);
     }
@@ -613,8 +615,8 @@ bool cmGlobalNinjaGenerator::FindMakeProgram(cmMakefile* mf)
   if (!this->cmGlobalGenerator::FindMakeProgram(mf)) {
     return false;
   }
-  if (const char* ninjaCommand = mf->GetDefinition("CMAKE_MAKE_PROGRAM")) {
-    this->NinjaCommand = ninjaCommand;
+  if (cmProp ninjaCommand = mf->GetDefinition("CMAKE_MAKE_PROGRAM")) {
+    this->NinjaCommand = *ninjaCommand;
     std::vector<std::string> command;
     command.push_back(this->NinjaCommand);
     command.emplace_back("--version");
@@ -679,6 +681,9 @@ void cmGlobalNinjaGenerator::CheckNinjaFeatures()
   this->NinjaSupportsRestatTool = !cmSystemTools::VersionCompare(
     cmSystemTools::OP_LESS, this->NinjaVersion.c_str(),
     RequiredNinjaVersionForRestatTool().c_str());
+  this->NinjaSupportsMultipleOutputs = !cmSystemTools::VersionCompare(
+    cmSystemTools::OP_LESS, this->NinjaVersion.c_str(),
+    RequiredNinjaVersionForMultipleOutputs().c_str());
 }
 
 bool cmGlobalNinjaGenerator::CheckLanguages(
@@ -687,6 +692,9 @@ bool cmGlobalNinjaGenerator::CheckLanguages(
   if (cm::contains(languages, "Fortran")) {
     return this->CheckFortran(mf);
   }
+  if (cm::contains(languages, "ISPC")) {
+    return this->CheckISPC(mf);
+  }
   if (cm::contains(languages, "Swift")) {
     const std::string architectures =
       mf->GetSafeDefinition("CMAKE_OSX_ARCHITECTURES");
@@ -720,6 +728,25 @@ bool cmGlobalNinjaGenerator::CheckFortran(cmMakefile* mf) const
   return false;
 }
 
+bool cmGlobalNinjaGenerator::CheckISPC(cmMakefile* mf) const
+{
+  if (this->NinjaSupportsMultipleOutputs) {
+    return true;
+  }
+
+  std::ostringstream e;
+  /* clang-format off */
+  e <<
+    "The Ninja generator does not support ISPC using Ninja version\n"
+    "  " << this->NinjaVersion << "\n"
+    "due to lack of required features.  Ninja 1.10 or higher is required."
+    ;
+  /* clang-format on */
+  mf->IssueMessage(MessageType::FATAL_ERROR, e.str());
+  cmSystemTools::SetFatalErrorOccured();
+  return false;
+}
+
 void cmGlobalNinjaGenerator::EnableLanguage(
   std::vector<std::string> const& langs, cmMakefile* mf, bool optional)
 {
@@ -1092,6 +1119,7 @@ void cmGlobalNinjaGenerator::AppendTargetOutputs(
     }
     // FALLTHROUGH
     case cmStateEnums::GLOBAL_TARGET:
+    case cmStateEnums::INTERFACE_LIBRARY:
     case cmStateEnums::UTILITY: {
       std::string path =
         cmStrCat(target->GetLocalGenerator()->GetCurrentBinaryDirectory(), '/',
@@ -1104,8 +1132,8 @@ void cmGlobalNinjaGenerator::AppendTargetOutputs(
       break;
     }
 
-    default:
-      return;
+    case cmStateEnums::UNKNOWN_LIBRARY:
+      break;
   }
 }
 
@@ -1125,15 +1153,38 @@ void cmGlobalNinjaGenerator::AppendTargetDepends(
     }
   } else {
     cmNinjaDeps outs;
+
+    auto computeISPCOuputs = [](cmGlobalNinjaGenerator* gg,
+                                cmGeneratorTarget const* depTarget,
+                                cmNinjaDeps& outputDeps,
+                                const std::string& targetConfig) {
+      if (depTarget->CanCompileSources()) {
+        auto headers = depTarget->GetGeneratedISPCHeaders(targetConfig);
+        if (!headers.empty()) {
+          std::transform(headers.begin(), headers.end(), headers.begin(),
+                         gg->MapToNinjaPath());
+          outputDeps.insert(outputDeps.end(), headers.begin(), headers.end());
+        }
+        auto objs = depTarget->GetGeneratedISPCObjects(targetConfig);
+        if (!objs.empty()) {
+          std::transform(objs.begin(), objs.end(), objs.begin(),
+                         gg->MapToNinjaPath());
+          outputDeps.insert(outputDeps.end(), objs.begin(), objs.end());
+        }
+      }
+    };
+
     for (cmTargetDepend const& targetDep :
          this->GetTargetDirectDepends(target)) {
-      if (targetDep->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+      if (!targetDep->IsInBuildSystem()) {
         continue;
       }
       if (targetDep.IsCross()) {
         this->AppendTargetOutputs(targetDep, outs, fileConfig, depends);
+        computeISPCOuputs(this, targetDep, outs, fileConfig);
       } else {
         this->AppendTargetOutputs(targetDep, outs, config, depends);
+        computeISPCOuputs(this, targetDep, outs, config);
       }
     }
     std::sort(outs.begin(), outs.end());
@@ -1169,7 +1220,7 @@ void cmGlobalNinjaGenerator::AppendTargetDependsClosure(
     cmNinjaOuts this_outs; // this will be the new cache entry
 
     for (auto const& dep_target : this->GetTargetDirectDepends(target)) {
-      if (dep_target->GetType() == cmStateEnums::INTERFACE_LIBRARY ||
+      if (!dep_target->IsInBuildSystem() ||
           (target->GetType() != cmStateEnums::UTILITY &&
            this->EnableCrossConfigBuild() && !dep_target.IsCross())) {
         continue;
@@ -1189,7 +1240,7 @@ void cmGlobalNinjaGenerator::AppendTargetDependsClosure(
   // finally generate the outputs of the target itself, if applicable
   cmNinjaDeps outs;
   if (!omit_self) {
-    this->AppendTargetOutputs(target, outs, config);
+    this->AppendTargetOutputs(target, outs, config, DependOnTargetArtifact);
   }
   outputs.insert(outs.begin(), outs.end());
 }
@@ -1201,14 +1252,15 @@ void cmGlobalNinjaGenerator::AddTargetAlias(const std::string& alias,
   std::string outputPath = this->NinjaOutputPath(alias);
   std::string buildAlias = this->BuildAlias(outputPath, config);
   cmNinjaDeps outputs;
-  this->AppendTargetOutputs(target, outputs, config);
+  this->AppendTargetOutputs(target, outputs, config, DependOnTargetArtifact);
   // Mark the target's outputs as ambiguous to ensure that no other target
   // uses the output as an alias.
   for (std::string const& output : outputs) {
     this->TargetAliases[output].GeneratorTarget = nullptr;
     this->DefaultTargetAliases[output].GeneratorTarget = nullptr;
     for (const std::string& config2 :
-         this->Makefiles.front()->GetGeneratorConfigs()) {
+         this->Makefiles.front()->GetGeneratorConfigs(
+           cmMakefile::IncludeEmptyConfig)) {
       this->Configs[config2].TargetAliases[output].GeneratorTarget = nullptr;
     }
   }
@@ -1266,11 +1318,12 @@ void cmGlobalNinjaGenerator::WriteTargetAliases(std::ostream& os)
     if (ta.second.Config == "all") {
       for (auto const& config : this->CrossConfigs) {
         this->AppendTargetOutputs(ta.second.GeneratorTarget,
-                                  build.ExplicitDeps, config);
+                                  build.ExplicitDeps, config,
+                                  DependOnTargetArtifact);
       }
     } else {
       this->AppendTargetOutputs(ta.second.GeneratorTarget, build.ExplicitDeps,
-                                ta.second.Config);
+                                ta.second.Config, DependOnTargetArtifact);
     }
     this->WriteBuild(this->EnableCrossConfigBuild() &&
                          (ta.second.Config == "all" ||
@@ -1281,7 +1334,8 @@ void cmGlobalNinjaGenerator::WriteTargetAliases(std::ostream& os)
   }
 
   if (this->IsMultiConfig()) {
-    for (auto const& config : this->Makefiles.front()->GetGeneratorConfigs()) {
+    for (auto const& config : this->Makefiles.front()->GetGeneratorConfigs(
+           cmMakefile::IncludeEmptyConfig)) {
       for (auto const& ta : this->Configs[config].TargetAliases) {
         // Don't write ambiguous aliases.
         if (!ta.second.GeneratorTarget) {
@@ -1297,7 +1351,8 @@ void cmGlobalNinjaGenerator::WriteTargetAliases(std::ostream& os)
         build.Outputs.front() = ta.first;
         build.ExplicitDeps.clear();
         this->AppendTargetOutputs(ta.second.GeneratorTarget,
-                                  build.ExplicitDeps, config);
+                                  build.ExplicitDeps, config,
+                                  DependOnTargetArtifact);
         this->WriteBuild(*this->GetConfigFileStream(config), build);
       }
     }
@@ -1319,7 +1374,8 @@ void cmGlobalNinjaGenerator::WriteTargetAliases(std::ostream& os)
         build.ExplicitDeps.clear();
         for (auto const& config : this->DefaultConfigs) {
           this->AppendTargetOutputs(ta.second.GeneratorTarget,
-                                    build.ExplicitDeps, config);
+                                    build.ExplicitDeps, config,
+                                    DependOnTargetArtifact);
         }
         this->WriteBuild(*this->GetDefaultFileStream(), build);
       }
@@ -1340,11 +1396,9 @@ void cmGlobalNinjaGenerator::WriteFolderTargets(std::ostream& os)
     cmGlobalNinjaGenerator::WriteDivider(os);
     std::string const& currentBinaryDir = it.first;
     DirectoryTarget const& dt = it.second;
-    std::vector<std::string> configs;
-    dt.LG->GetMakefile()->GetConfigurations(configs, true);
-    if (configs.empty()) {
-      configs.emplace_back();
-    }
+    std::vector<std::string> configs =
+      dt.LG->GetMakefile()->GetGeneratorConfigs(
+        cmMakefile::IncludeEmptyConfig);
 
     // Setup target
     cmNinjaDeps configDeps;
@@ -1357,8 +1411,9 @@ void cmGlobalNinjaGenerator::WriteFolderTargets(std::ostream& os)
       build.Outputs.front() = this->BuildAlias(buildDirAllTarget, config);
       configDeps.emplace_back(build.Outputs.front());
       for (DirectoryTarget::Target const& t : dt.Targets) {
-        if (!t.ExcludeFromAll) {
-          this->AppendTargetOutputs(t.GT, build.ExplicitDeps, config);
+        if (!IsExcludedFromAllInConfig(t, config)) {
+          this->AppendTargetOutputs(t.GT, build.ExplicitDeps, config,
+                                    DependOnTargetArtifact);
         }
       }
       for (DirectoryTarget::Dir const& d : dt.Children) {
@@ -1539,7 +1594,8 @@ void cmGlobalNinjaGenerator::WriteBuiltinTargets(std::ostream& os)
   this->WriteTargetClean(os);
   this->WriteTargetHelp(os);
 
-  for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs()) {
+  for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs(
+         cmMakefile::IncludeEmptyConfig)) {
     this->WriteTargetDefault(*this->GetConfigFileStream(config));
   }
 
@@ -1713,11 +1769,8 @@ bool cmGlobalNinjaGenerator::WriteTargetCleanAdditional(std::ostream& os)
   std::string cleanScriptRel = "CMakeFiles/clean_additional.cmake";
   std::string cleanScriptAbs =
     cmStrCat(lgr->GetBinaryDirectory(), '/', cleanScriptRel);
-  std::vector<std::string> configs;
-  this->Makefiles[0]->GetConfigurations(configs, true);
-  if (configs.empty()) {
-    configs.emplace_back();
-  }
+  std::vector<std::string> configs =
+    this->Makefiles[0]->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
   // Check if there are additional files to clean
   bool empty = true;
@@ -1811,7 +1864,8 @@ void cmGlobalNinjaGenerator::WriteTargetClean(std::ostream& os)
     WriteRule(*this->RulesFileStream, rule);
   }
 
-  auto const configs = this->Makefiles.front()->GetGeneratorConfigs();
+  auto const configs = this->Makefiles.front()->GetGeneratorConfigs(
+    cmMakefile::IncludeEmptyConfig);
 
   // Write build
   {
@@ -2491,7 +2545,8 @@ bool cmGlobalNinjaMultiGenerator::OpenBuildFileStreams()
     << "# This file contains build statements common to all "
        "configurations.\n\n";
 
-  for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs()) {
+  for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs(
+         cmMakefile::IncludeEmptyConfig)) {
     // Open impl file.
     if (!this->OpenFileStream(this->ImplFileStreams[config],
                               GetNinjaImplFilename(config))) {
@@ -2531,7 +2586,8 @@ void cmGlobalNinjaMultiGenerator::CloseBuildFileStreams()
     this->DefaultFileStream.reset();
   } // No error if it wasn't open
 
-  for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs()) {
+  for (auto const& config : this->Makefiles[0]->GetGeneratorConfigs(
+         cmMakefile::IncludeEmptyConfig)) {
     if (this->ImplFileStreams[config]) {
       this->ImplFileStreams[config].reset();
     } else {
@@ -2573,7 +2629,8 @@ std::string cmGlobalNinjaMultiGenerator::GetNinjaConfigFilename(
 void cmGlobalNinjaMultiGenerator::AddRebuildManifestOutputs(
   cmNinjaDeps& outputs) const
 {
-  for (auto const& config : this->Makefiles.front()->GetGeneratorConfigs()) {
+  for (auto const& config : this->Makefiles.front()->GetGeneratorConfigs(
+         cmMakefile::IncludeEmptyConfig)) {
     outputs.push_back(this->NinjaOutputPath(GetNinjaImplFilename(config)));
     outputs.push_back(this->NinjaOutputPath(GetNinjaConfigFilename(config)));
   }
@@ -2585,11 +2642,9 @@ void cmGlobalNinjaMultiGenerator::AddRebuildManifestOutputs(
 void cmGlobalNinjaMultiGenerator::GetQtAutoGenConfigs(
   std::vector<std::string>& configs) const
 {
-  auto const oldSize = configs.size();
-  this->Makefiles.front()->GetConfigurations(configs);
-  if (configs.size() == oldSize) {
-    configs.emplace_back();
-  }
+  auto allConfigs =
+    this->Makefiles[0]->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
+  configs.insert(configs.end(), cm::cbegin(allConfigs), cm::cend(allConfigs));
 }
 
 bool cmGlobalNinjaMultiGenerator::InspectConfigTypeVariables()
diff --git a/Source/cmGlobalNinjaGenerator.h b/Source/cmGlobalNinjaGenerator.h
index 44e632f..884a711 100644
--- a/Source/cmGlobalNinjaGenerator.h
+++ b/Source/cmGlobalNinjaGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalNinjaGenerator_h
-#define cmGlobalNinjaGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -318,14 +317,13 @@ public:
   virtual std::string OrderDependsTargetForTarget(
     cmGeneratorTarget const* target, const std::string& config) const;
 
-  void AppendTargetOutputs(
-    cmGeneratorTarget const* target, cmNinjaDeps& outputs,
-    const std::string& config,
-    cmNinjaTargetDepends depends = DependOnTargetArtifact);
-  void AppendTargetDepends(
-    cmGeneratorTarget const* target, cmNinjaDeps& outputs,
-    const std::string& config, const std::string& fileConfig,
-    cmNinjaTargetDepends depends = DependOnTargetArtifact);
+  void AppendTargetOutputs(cmGeneratorTarget const* target,
+                           cmNinjaDeps& outputs, const std::string& config,
+                           cmNinjaTargetDepends depends);
+  void AppendTargetDepends(cmGeneratorTarget const* target,
+                           cmNinjaDeps& outputs, const std::string& config,
+                           const std::string& fileConfig,
+                           cmNinjaTargetDepends depends);
   void AppendTargetDependsClosure(cmGeneratorTarget const* target,
                                   cmNinjaDeps& outputs,
                                   const std::string& config);
@@ -371,6 +369,10 @@ public:
     return "1.10";
   }
   static std::string RequiredNinjaVersionForCleanDeadTool() { return "1.10"; }
+  static std::string RequiredNinjaVersionForMultipleOutputs()
+  {
+    return "1.10";
+  }
   bool SupportsConsolePool() const;
   bool SupportsImplicitOuts() const;
   bool SupportsManifestRestat() const;
@@ -448,6 +450,7 @@ private:
   bool CheckLanguages(std::vector<std::string> const& languages,
                       cmMakefile* mf) const override;
   bool CheckFortran(cmMakefile* mf) const;
+  bool CheckISPC(cmMakefile* mf) const;
 
   void CloseCompileCommandsStream();
 
@@ -534,6 +537,7 @@ private:
   bool NinjaSupportsRestatTool = false;
   bool NinjaSupportsUnconditionalRecompactTool = false;
   bool NinjaSupportsCleanDeadTool = false;
+  bool NinjaSupportsMultipleOutputs = false;
 
 private:
   void InitOutputPathPrefix();
@@ -664,5 +668,3 @@ private:
   std::unique_ptr<cmGeneratedFileStream> CommonFileStream;
   std::unique_ptr<cmGeneratedFileStream> DefaultFileStream;
 };
-
-#endif // ! cmGlobalNinjaGenerator_h
diff --git a/Source/cmGlobalUnixMakefileGenerator3.cxx b/Source/cmGlobalUnixMakefileGenerator3.cxx
index c31983b..37a77fa 100644
--- a/Source/cmGlobalUnixMakefileGenerator3.cxx
+++ b/Source/cmGlobalUnixMakefileGenerator3.cxx
@@ -143,7 +143,7 @@ void cmGlobalUnixMakefileGenerator3::Generate()
     total += pmi.second.NumberOfActions;
   }
 
-  // write each target's progress.make this loop is done twice. Bascially the
+  // write each target's progress.make this loop is done twice. Basically the
   // Generate pass counts all the actions, the first loop below determines
   // how many actions have progress updates for each target and writes to
   // corrrect variable values for everything except the all targets. The
@@ -387,12 +387,8 @@ void cmGlobalUnixMakefileGenerator3::WriteMainCMakefileLanguageRules(
       cm::static_reference_cast<cmLocalUnixMakefileGenerator3>(lGenerator);
     // for all of out targets
     for (const auto& tgt : lg.GetGeneratorTargets()) {
-      if ((tgt->GetType() == cmStateEnums::EXECUTABLE) ||
-          (tgt->GetType() == cmStateEnums::STATIC_LIBRARY) ||
-          (tgt->GetType() == cmStateEnums::SHARED_LIBRARY) ||
-          (tgt->GetType() == cmStateEnums::MODULE_LIBRARY) ||
-          (tgt->GetType() == cmStateEnums::OBJECT_LIBRARY) ||
-          (tgt->GetType() == cmStateEnums::UTILITY)) {
+      if (tgt->IsInBuildSystem() &&
+          tgt->GetType() != cmStateEnums::GLOBAL_TARGET) {
         std::string tname = cmStrCat(lg.GetRelativeTargetDirectory(tgt.get()),
                                      "/DependInfo.cmake");
         cmSystemTools::ConvertToUnixSlashes(tname);
@@ -416,7 +412,7 @@ void cmGlobalUnixMakefileGenerator3::WriteDirectoryRule2(
   std::vector<std::string> depends;
   for (DirectoryTarget::Target const& t : dt.Targets) {
     // Add this to the list of depends rules in this directory.
-    if ((!check_all || !t.ExcludeFromAll) &&
+    if ((!check_all || t.ExcludedFromAllInConfigs.empty()) &&
         (!check_relink ||
          t.GT->NeedRelinkBeforeInstall(lg->GetConfigName()))) {
       // The target may be from a different directory; use its local gen.
@@ -635,17 +631,12 @@ void cmGlobalUnixMakefileGenerator3::WriteConvenienceRules(
     for (const auto& gtarget : lg.GetGeneratorTargets()) {
       // Don't emit the same rule twice (e.g. two targets with the same
       // simple name)
-      int type = gtarget->GetType();
       std::string name = gtarget->GetName();
       if (!name.empty() && emitted.insert(name).second &&
           // Handle user targets here.  Global targets are handled in
           // the local generator on a per-directory basis.
-          ((type == cmStateEnums::EXECUTABLE) ||
-           (type == cmStateEnums::STATIC_LIBRARY) ||
-           (type == cmStateEnums::SHARED_LIBRARY) ||
-           (type == cmStateEnums::MODULE_LIBRARY) ||
-           (type == cmStateEnums::OBJECT_LIBRARY) ||
-           (type == cmStateEnums::UTILITY))) {
+          (gtarget->IsInBuildSystem() &&
+           gtarget->GetType() != cmStateEnums::GLOBAL_TARGET)) {
         // Add a rule to build the target by name.
         lg.WriteDivider(ruleFileStream);
         ruleFileStream << "# Target rules for targets named " << name
@@ -709,15 +700,10 @@ void cmGlobalUnixMakefileGenerator3::WriteConvenienceRules2(
 
   // for each target Generate the rule files for each target.
   for (const auto& gtarget : lg.GetGeneratorTargets()) {
-    int type = gtarget->GetType();
     std::string name = gtarget->GetName();
     if (!name.empty() &&
-        ((type == cmStateEnums::EXECUTABLE) ||
-         (type == cmStateEnums::STATIC_LIBRARY) ||
-         (type == cmStateEnums::SHARED_LIBRARY) ||
-         (type == cmStateEnums::MODULE_LIBRARY) ||
-         (type == cmStateEnums::OBJECT_LIBRARY) ||
-         (type == cmStateEnums::UTILITY))) {
+        (gtarget->IsInBuildSystem() &&
+         gtarget->GetType() != cmStateEnums::GLOBAL_TARGET)) {
       std::string makefileName;
       // Add a rule to build the target by name.
       localName = lg.GetRelativeTargetDirectory(gtarget.get());
@@ -845,8 +831,7 @@ void cmGlobalUnixMakefileGenerator3::InitializeProgressMarks()
     for (const auto& gt : lg->GetGeneratorTargets()) {
       cmLocalGenerator* tlg = gt->GetLocalGenerator();
 
-      if (gt->GetType() == cmStateEnums::INTERFACE_LIBRARY ||
-          gt->GetPropertyAsBool("EXCLUDE_FROM_ALL")) {
+      if (!gt->IsInBuildSystem() || IsExcluded(lg.get(), gt.get())) {
         continue;
       }
 
@@ -881,7 +866,7 @@ size_t cmGlobalUnixMakefileGenerator3::CountProgressMarksInTarget(
   if (emitted.insert(target).second) {
     count = this->ProgressMap[target].Marks.size();
     for (cmTargetDepend const& depend : this->GetTargetDirectDepends(target)) {
-      if (depend->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+      if (!depend->IsInBuildSystem()) {
         continue;
       }
       count += this->CountProgressMarksInTarget(depend, emitted);
@@ -938,7 +923,7 @@ void cmGlobalUnixMakefileGenerator3::AppendGlobalTargetDepends(
   for (cmTargetDepend const& i : this->GetTargetDirectDepends(target)) {
     // Create the target-level dependency.
     cmGeneratorTarget const* dep = i;
-    if (dep->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!dep->IsInBuildSystem()) {
       continue;
     }
     cmLocalUnixMakefileGenerator3* lg3 =
@@ -986,7 +971,9 @@ void cmGlobalUnixMakefileGenerator3::WriteHelpRule(
             (type == cmStateEnums::STATIC_LIBRARY) ||
             (type == cmStateEnums::SHARED_LIBRARY) ||
             (type == cmStateEnums::MODULE_LIBRARY) ||
-            (type == cmStateEnums::OBJECT_LIBRARY)) {
+            (type == cmStateEnums::OBJECT_LIBRARY) ||
+            (type == cmStateEnums::INTERFACE_LIBRARY &&
+             target->IsInBuildSystem())) {
           project_targets.insert(target->GetName());
         } else if (type == cmStateEnums::GLOBAL_TARGET) {
           globals_targets.insert(target->GetName());
diff --git a/Source/cmGlobalUnixMakefileGenerator3.h b/Source/cmGlobalUnixMakefileGenerator3.h
index 1caa4b7..77d0827 100644
--- a/Source/cmGlobalUnixMakefileGenerator3.h
+++ b/Source/cmGlobalUnixMakefileGenerator3.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalUnixMakefileGenerator3_h
-#define cmGlobalUnixMakefileGenerator3_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -259,5 +258,3 @@ private:
     DirectoryTargetsMap;
   void InitializeProgressMarks() override;
 };
-
-#endif
diff --git a/Source/cmGlobalVisualStudio10Generator.cxx b/Source/cmGlobalVisualStudio10Generator.cxx
index 5dac072..3805546 100644
--- a/Source/cmGlobalVisualStudio10Generator.cxx
+++ b/Source/cmGlobalVisualStudio10Generator.cxx
@@ -138,9 +138,6 @@ cmGlobalVisualStudio10Generator::cmGlobalVisualStudio10Generator(
     "ProductDir",
     vc10Express, cmSystemTools::KeyWOW64_32);
   this->CudaEnabled = false;
-  this->SystemIsWindowsCE = false;
-  this->SystemIsWindowsPhone = false;
-  this->SystemIsWindowsStore = false;
   this->MSBuildCommandInitialized = false;
   {
     std::string envPlatformToolset;
@@ -511,18 +508,16 @@ bool cmGlobalVisualStudio10Generator::InitializeSystem(cmMakefile* mf)
       mf->IssueMessage(MessageType::FATAL_ERROR, e.str());
       return false;
     }
-    std::string v = this->GetInstalledNsightTegraVersion();
-    if (v.empty()) {
-      mf->IssueMessage(MessageType::FATAL_ERROR,
-                       "CMAKE_SYSTEM_NAME is 'Android' but "
-                       "'NVIDIA Nsight Tegra Visual Studio Edition' "
-                       "is not installed.");
-      return false;
+    if (mf->GetSafeDefinition("CMAKE_GENERATOR_PLATFORM") == "Tegra-Android") {
+      if (!this->InitializeTegraAndroid(mf)) {
+        return false;
+      }
+    } else {
+      this->SystemIsAndroid = true;
+      if (!this->InitializeAndroid(mf)) {
+        return false;
+      }
     }
-    this->DefaultPlatformName = "Tegra-Android";
-    this->DefaultPlatformToolset = "Default";
-    this->NsightTegraVersion = v;
-    mf->AddDefinition("CMAKE_VS_NsightTegra_VERSION", v);
   }
 
   return true;
@@ -564,6 +559,31 @@ bool cmGlobalVisualStudio10Generator::InitializeWindowsStore(cmMakefile* mf)
   return false;
 }
 
+bool cmGlobalVisualStudio10Generator::InitializeTegraAndroid(cmMakefile* mf)
+{
+  std::string v = this->GetInstalledNsightTegraVersion();
+  if (v.empty()) {
+    mf->IssueMessage(MessageType::FATAL_ERROR,
+                     "CMAKE_SYSTEM_NAME is 'Android' but "
+                     "'NVIDIA Nsight Tegra Visual Studio Edition' "
+                     "is not installed.");
+    return false;
+  }
+  this->DefaultPlatformName = "Tegra-Android";
+  this->DefaultPlatformToolset = "Default";
+  this->NsightTegraVersion = v;
+  mf->AddDefinition("CMAKE_VS_NsightTegra_VERSION", v);
+  return true;
+}
+
+bool cmGlobalVisualStudio10Generator::InitializeAndroid(cmMakefile* mf)
+{
+  std::ostringstream e;
+  e << this->GetName() << " does not support Android.";
+  mf->IssueMessage(MessageType::FATAL_ERROR, e.str());
+  return false;
+}
+
 bool cmGlobalVisualStudio10Generator::SelectWindowsPhoneToolset(
   std::string& toolset) const
 {
@@ -598,6 +618,28 @@ void cmGlobalVisualStudio10Generator::Generate()
 {
   this->LongestSource = LongestSourcePath();
   this->cmGlobalVisualStudio8Generator::Generate();
+  if (!this->AndroidExecutableWarnings.empty() &&
+      !this->CMakeInstance->GetIsInTryCompile()) {
+    std::ostringstream e;
+    /* clang-format off */
+    e <<
+      "You are using Visual Studio tools for Android, which does not support "
+      "standalone executables. However, the following executable targets do "
+      "not have the ANDROID_GUI property set, and thus will not be built as "
+      "expected. They will be built as shared libraries with executable "
+      "filenames:\n"
+      "  ";
+    /* clang-format on */
+    bool first = true;
+    for (auto const& name : this->AndroidExecutableWarnings) {
+      if (!first) {
+        e << ", ";
+      }
+      first = false;
+      e << name;
+    }
+    this->CMakeInstance->IssueMessage(MessageType::WARNING, e.str());
+  }
   if (this->LongestSource.Length > 0) {
     cmLocalGenerator* lg = this->LongestSource.Target->GetLocalGenerator();
     std::ostringstream e;
@@ -664,8 +706,14 @@ std::string const& cmGlobalVisualStudio10Generator::GetPlatformToolsetString()
   if (!this->GeneratorToolset.empty()) {
     return this->GeneratorToolset;
   }
-  if (!this->DefaultPlatformToolset.empty()) {
-    return this->DefaultPlatformToolset;
+  if (this->SystemIsAndroid) {
+    if (!this->DefaultAndroidToolset.empty()) {
+      return this->DefaultAndroidToolset;
+    }
+  } else {
+    if (!this->DefaultPlatformToolset.empty()) {
+      return this->DefaultPlatformToolset;
+    }
   }
   static std::string const empty;
   return empty;
@@ -879,7 +927,10 @@ bool cmGlobalVisualStudio10Generator::FindVCTargetsPath(cmMakefile* mf)
       epg.Attribute("Label", "Globals");
       cmXMLElement(epg, "ProjectGuid")
         .Content("{F3FC6D86-508D-3FB1-96D2-995F08B142EC}");
-      cmXMLElement(epg, "Keyword").Content("Win32Proj");
+      cmXMLElement(epg, "Keyword")
+        .Content(mf->GetSafeDefinition("CMAKE_SYSTEM_NAME") == "Android"
+                   ? "Android"
+                   : "Win32Proj");
       cmXMLElement(epg, "Platform").Content(this->GetPlatformName());
       if (this->GetSystemName() == "WindowsPhone") {
         cmXMLElement(epg, "ApplicationType").Content("Windows Phone");
@@ -889,15 +940,21 @@ bool cmGlobalVisualStudio10Generator::FindVCTargetsPath(cmMakefile* mf)
         cmXMLElement(epg, "ApplicationType").Content("Windows Store");
         cmXMLElement(epg, "ApplicationTypeRevision")
           .Content(this->GetApplicationTypeRevision());
+      } else if (this->GetSystemName() == "Android") {
+        cmXMLElement(epg, "ApplicationType").Content("Android");
+        cmXMLElement(epg, "ApplicationTypeRevision")
+          .Content(this->GetApplicationTypeRevision());
       }
       if (!this->WindowsTargetPlatformVersion.empty()) {
         cmXMLElement(epg, "WindowsTargetPlatformVersion")
           .Content(this->WindowsTargetPlatformVersion);
       }
-      if (this->GetPlatformName() == "ARM64") {
-        cmXMLElement(epg, "WindowsSDKDesktopARM64Support").Content("true");
-      } else if (this->GetPlatformName() == "ARM") {
-        cmXMLElement(epg, "WindowsSDKDesktopARMSupport").Content("true");
+      if (this->GetSystemName() != "Android") {
+        if (this->GetPlatformName() == "ARM64") {
+          cmXMLElement(epg, "WindowsSDKDesktopARM64Support").Content("true");
+        } else if (this->GetPlatformName() == "ARM") {
+          cmXMLElement(epg, "WindowsSDKDesktopARMSupport").Content("true");
+        }
       }
     }
     cmXMLElement(eprj, "Import")
@@ -1209,6 +1266,10 @@ std::string cmGlobalVisualStudio10Generator::GetInstalledNsightTegraVersion()
 
 std::string cmGlobalVisualStudio10Generator::GetApplicationTypeRevision() const
 {
+  if (this->GetSystemName() == "Android") {
+    return this->GetAndroidApplicationTypeRevision();
+  }
+
   // Return the first two '.'-separated components of the Windows version.
   std::string::size_type end1 = this->SystemVersion.find('.');
   std::string::size_type end2 =
diff --git a/Source/cmGlobalVisualStudio10Generator.h b/Source/cmGlobalVisualStudio10Generator.h
index b8c18b4..65ea33f 100644
--- a/Source/cmGlobalVisualStudio10Generator.h
+++ b/Source/cmGlobalVisualStudio10Generator.h
@@ -1,9 +1,9 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio10Generator_h
-#define cmGlobalVisualStudio10Generator_h
+#pragma once
 
 #include <memory>
+#include <set>
 
 #include "cmGlobalVisualStudio8Generator.h"
 #include "cmVisualStudio10ToolsetOptions.h"
@@ -43,6 +43,11 @@ public:
   void EnableLanguage(std::vector<std::string> const& languages, cmMakefile*,
                       bool optional) override;
 
+  void AddAndroidExecutableWarning(const std::string& name)
+  {
+    this->AndroidExecutableWarnings.insert(name);
+  }
+
   bool IsCudaEnabled() const { return this->CudaEnabled; }
 
   /** Generating for Nsight Tegra VS plugin?  */
@@ -100,6 +105,9 @@ public:
   /** Return true if building for WindowsStore */
   bool TargetsWindowsStore() const { return this->SystemIsWindowsStore; }
 
+  /** Return true if building for Android */
+  bool TargetsAndroid() const { return this->SystemIsAndroid; }
+
   const char* GetCMakeCFGIntDir() const override { return "$(Configuration)"; }
   bool Find64BitTools(cmMakefile* mf);
 
@@ -128,6 +136,8 @@ public:
   /** Return the first two components of CMAKE_SYSTEM_VERSION.  */
   std::string GetApplicationTypeRevision() const;
 
+  virtual const char* GetAndroidApplicationTypeRevision() const { return ""; }
+
   cmIDEFlagTable const* GetClFlagTable() const;
   cmIDEFlagTable const* GetCSharpFlagTable() const;
   cmIDEFlagTable const* GetRcFlagTable() const;
@@ -148,6 +158,8 @@ protected:
   virtual bool InitializeWindowsCE(cmMakefile* mf);
   virtual bool InitializeWindowsPhone(cmMakefile* mf);
   virtual bool InitializeWindowsStore(cmMakefile* mf);
+  virtual bool InitializeTegraAndroid(cmMakefile* mf);
+  virtual bool InitializeAndroid(cmMakefile* mf);
 
   virtual bool ProcessGeneratorToolsetField(std::string const& key,
                                             std::string const& value);
@@ -171,6 +183,7 @@ protected:
   std::string GeneratorToolsetCudaCustomDir;
   std::string DefaultPlatformToolset;
   std::string DefaultPlatformToolsetHostArchitecture;
+  std::string DefaultAndroidToolset;
   std::string WindowsTargetPlatformVersion;
   std::string SystemName;
   std::string SystemVersion;
@@ -185,9 +198,10 @@ protected:
   std::string DefaultNasmFlagTableName;
   std::string DefaultRCFlagTableName;
   bool SupportsUnityBuilds = false;
-  bool SystemIsWindowsCE;
-  bool SystemIsWindowsPhone;
-  bool SystemIsWindowsStore;
+  bool SystemIsWindowsCE = false;
+  bool SystemIsWindowsPhone = false;
+  bool SystemIsWindowsStore = false;
+  bool SystemIsAndroid = false;
 
 private:
   class Factory;
@@ -211,6 +225,7 @@ private:
   std::string MSBuildCommand;
   bool MSBuildCommandInitialized;
   cmVisualStudio10ToolsetOptions ToolsetOptions;
+  std::set<std::string> AndroidExecutableWarnings;
   virtual std::string FindMSBuildCommand();
   std::string FindDevEnvCommand() override;
   std::string GetVSMakeProgram() override { return this->GetMSBuildCommand(); }
@@ -228,4 +243,3 @@ private:
   // We do not use the reload macros for VS >= 10.
   std::string GetUserMacrosDirectory() override { return ""; }
 };
-#endif
diff --git a/Source/cmGlobalVisualStudio11Generator.h b/Source/cmGlobalVisualStudio11Generator.h
index 5f1ff73..6e409cf 100644
--- a/Source/cmGlobalVisualStudio11Generator.h
+++ b/Source/cmGlobalVisualStudio11Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio11Generator_h
-#define cmGlobalVisualStudio11Generator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -53,4 +52,3 @@ private:
   class Factory;
   friend class Factory;
 };
-#endif
diff --git a/Source/cmGlobalVisualStudio12Generator.h b/Source/cmGlobalVisualStudio12Generator.h
index bdd40ff..c220d40 100644
--- a/Source/cmGlobalVisualStudio12Generator.h
+++ b/Source/cmGlobalVisualStudio12Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio12Generator_h
-#define cmGlobalVisualStudio12Generator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -48,4 +47,3 @@ private:
   class Factory;
   friend class Factory;
 };
-#endif
diff --git a/Source/cmGlobalVisualStudio14Generator.cxx b/Source/cmGlobalVisualStudio14Generator.cxx
index f549b6a..a12b7e1 100644
--- a/Source/cmGlobalVisualStudio14Generator.cxx
+++ b/Source/cmGlobalVisualStudio14Generator.cxx
@@ -109,6 +109,7 @@ cmGlobalVisualStudio14Generator::cmGlobalVisualStudio14Generator(
     "ProductDir",
     vc14Express, cmSystemTools::KeyWOW64_32);
   this->DefaultPlatformToolset = "v140";
+  this->DefaultAndroidToolset = "Clang_3_8";
   this->DefaultCLFlagTableName = "v140";
   this->DefaultCSharpFlagTableName = "v140";
   this->DefaultLibFlagTableName = "v14";
@@ -159,11 +160,17 @@ bool cmGlobalVisualStudio14Generator::InitializeWindowsStore(cmMakefile* mf)
   return true;
 }
 
+bool cmGlobalVisualStudio14Generator::InitializeAndroid(cmMakefile*)
+{
+  return true;
+}
+
 bool cmGlobalVisualStudio14Generator::SelectWindows10SDK(cmMakefile* mf,
                                                          bool required)
 {
   // Find the default version of the Windows 10 SDK.
-  std::string const version = this->GetWindows10SDKVersion();
+  std::string const version = this->GetWindows10SDKVersion(mf);
+
   if (required && version.empty()) {
     std::ostringstream e;
     e << "Could not find an appropriate version of the Windows 10 SDK"
@@ -227,8 +234,25 @@ bool cmGlobalVisualStudio14Generator::IsWindowsStoreToolsetInstalled() const
                                           cmSystemTools::KeyWOW64_32);
 }
 
-std::string cmGlobalVisualStudio14Generator::GetWindows10SDKMaxVersion() const
+std::string cmGlobalVisualStudio14Generator::GetWindows10SDKMaxVersion(
+  cmMakefile* mf) const
 {
+  // if the given value is set, it can either be OFF/FALSE or a valid SDK
+  // string
+  if (cmProp value = mf->GetDefinition(
+        "CMAKE_VS_WINDOWS_TARGET_PLATFORM_VERSION_MAXIMUM")) {
+
+    // If the value is some off/false value, then there is NO maximum set.
+    if (cmIsOff(value)) {
+      return std::string();
+    }
+    // If the value is something else, trust that it is a valid SDK value.
+    else if (value) {
+      return *value;
+    }
+    // If value is an invalid pointer, leave result unchanged.
+  }
+
   // The last Windows 10 SDK version that VS 2015 can target is 10.0.14393.0.
   //
   // "VS 2015 Users: The Windows 10 SDK (15063, 16299, 17134, 17763) is
@@ -261,7 +285,8 @@ public:
 };
 #endif
 
-std::string cmGlobalVisualStudio14Generator::GetWindows10SDKVersion()
+std::string cmGlobalVisualStudio14Generator::GetWindows10SDKVersion(
+  cmMakefile* mf)
 {
 #if defined(_WIN32) && !defined(__CYGWIN__)
   std::vector<std::string> win10Roots;
@@ -311,8 +336,10 @@ std::string cmGlobalVisualStudio14Generator::GetWindows10SDKVersion()
     i = cmSystemTools::GetFilenameName(i);
   }
 
-  // Skip SDKs that cannot be used with our toolset.
-  std::string maxVersion = this->GetWindows10SDKMaxVersion();
+  // Skip SDKs that cannot be used with our toolset, unless the user does not
+  // want to limit the highest supported SDK according to the Microsoft
+  // documentation.
+  std::string maxVersion = this->GetWindows10SDKMaxVersion(mf);
   if (!maxVersion.empty()) {
     cm::erase_if(sdks, WindowsSDKTooRecent(maxVersion));
   }
diff --git a/Source/cmGlobalVisualStudio14Generator.h b/Source/cmGlobalVisualStudio14Generator.h
index ccc2917..1ccd4c7 100644
--- a/Source/cmGlobalVisualStudio14Generator.h
+++ b/Source/cmGlobalVisualStudio14Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio14Generator_h
-#define cmGlobalVisualStudio14Generator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -23,12 +22,18 @@ public:
 
   bool MatchesGeneratorName(const std::string& name) const override;
 
+  const char* GetAndroidApplicationTypeRevision() const override
+  {
+    return "2.0";
+  }
+
 protected:
   cmGlobalVisualStudio14Generator(cmake* cm, const std::string& name,
                                   std::string const& platformInGeneratorName);
 
   bool InitializeWindows(cmMakefile* mf) override;
   bool InitializeWindowsStore(cmMakefile* mf) override;
+  bool InitializeAndroid(cmMakefile* mf) override;
   bool SelectWindowsStoreToolset(std::string& toolset) const override;
 
   // These aren't virtual because we need to check if the selected version
@@ -37,7 +42,7 @@ protected:
 
   // Used to make sure that the Windows 10 SDK selected can work with the
   // version of the toolset.
-  virtual std::string GetWindows10SDKMaxVersion() const;
+  virtual std::string GetWindows10SDKMaxVersion(cmMakefile* mf) const;
 
   virtual bool SelectWindows10SDK(cmMakefile* mf, bool required);
 
@@ -48,10 +53,9 @@ protected:
   // installed on the machine.
   bool IsWindowsDesktopToolsetInstalled() const override;
 
-  std::string GetWindows10SDKVersion();
+  std::string GetWindows10SDKVersion(cmMakefile* mf);
 
 private:
   class Factory;
   friend class Factory;
 };
-#endif
diff --git a/Source/cmGlobalVisualStudio71Generator.cxx b/Source/cmGlobalVisualStudio71Generator.cxx
index 7ada325..0083c40 100644
--- a/Source/cmGlobalVisualStudio71Generator.cxx
+++ b/Source/cmGlobalVisualStudio71Generator.cxx
@@ -19,8 +19,8 @@ void cmGlobalVisualStudio71Generator::WriteSLNFile(
   std::ostream& fout, cmLocalGenerator* root,
   std::vector<cmLocalGenerator*>& generators)
 {
-  std::vector<std::string> configs;
-  root->GetMakefile()->GetConfigurations(configs);
+  std::vector<std::string> configs =
+    root->GetMakefile()->GetGeneratorConfigs(cmMakefile::ExcludeEmptyConfig);
 
   // Write out the header for a SLN file
   this->WriteSLNHeader(fout);
diff --git a/Source/cmGlobalVisualStudio71Generator.h b/Source/cmGlobalVisualStudio71Generator.h
index 7eadaf3..7d38199 100644
--- a/Source/cmGlobalVisualStudio71Generator.h
+++ b/Source/cmGlobalVisualStudio71Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio71Generator_h
-#define cmGlobalVisualStudio71Generator_h
+#pragma once
 
 #include "cmGlobalVisualStudio7Generator.h"
 
@@ -42,4 +41,3 @@ protected:
 
   std::string ProjectConfigurationSectionName;
 };
-#endif
diff --git a/Source/cmGlobalVisualStudio7Generator.cxx b/Source/cmGlobalVisualStudio7Generator.cxx
index 428c748..84cfaeb 100644
--- a/Source/cmGlobalVisualStudio7Generator.cxx
+++ b/Source/cmGlobalVisualStudio7Generator.cxx
@@ -339,7 +339,7 @@ void cmGlobalVisualStudio7Generator::WriteTargetConfigurations(
   // loop over again and write out configurations for each target
   // in the solution
   for (cmGeneratorTarget const* target : projectTargets) {
-    if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!target->IsInBuildSystem()) {
       continue;
     }
     cmProp expath = target->GetProperty("EXTERNAL_MSPROJECT");
@@ -369,7 +369,7 @@ void cmGlobalVisualStudio7Generator::WriteTargetsToSolution(
 
   std::string rootBinaryDir = root->GetCurrentBinaryDirectory();
   for (cmGeneratorTarget const* target : projectTargets) {
-    if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!target->IsInBuildSystem()) {
       continue;
     }
     bool written = false;
@@ -381,8 +381,7 @@ void cmGlobalVisualStudio7Generator::WriteTargetsToSolution(
       std::string location = *expath;
 
       cmProp p = target->GetProperty("VS_PROJECT_TYPE");
-      this->WriteExternalProject(fout, project, location,
-                                 p ? p->c_str() : nullptr,
+      this->WriteExternalProject(fout, project, location, cmToCStr(p),
                                  target->GetUtilities());
       written = true;
     } else {
@@ -436,7 +435,7 @@ void cmGlobalVisualStudio7Generator::WriteTargetDepends(
   std::ostream& fout, OrderedTargetDependSet const& projectTargets)
 {
   for (cmGeneratorTarget const* target : projectTargets) {
-    if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!target->IsInBuildSystem()) {
       continue;
     }
     cmProp vcprojName = target->GetProperty("GENERATOR_FILE_NAME");
@@ -568,8 +567,9 @@ void cmGlobalVisualStudio7Generator::WriteSLNFooter(std::ostream& fout)
 std::string cmGlobalVisualStudio7Generator::WriteUtilityDepend(
   cmGeneratorTarget const* target)
 {
-  std::vector<std::string> configs;
-  target->Target->GetMakefile()->GetConfigurations(configs);
+  std::vector<std::string> configs =
+    target->Target->GetMakefile()->GetGeneratorConfigs(
+      cmMakefile::ExcludeEmptyConfig);
   std::string pname = cmStrCat(target->GetName(), "_UTILITY");
   std::string fname =
     cmStrCat(target->GetLocalGenerator()->GetCurrentBinaryDirectory(), '/',
@@ -675,11 +675,11 @@ std::set<std::string> cmGlobalVisualStudio7Generator::IsPartOfDefaultBuild(
           "CMAKE_VS_INCLUDE_" + t + "_TO_DEFAULT_BUILD";
         // inspect CMAKE_VS_INCLUDE_<t>_TO_DEFAULT_BUILD properties
         for (std::string const& i : configs) {
-          const char* propertyValue =
+          cmProp propertyValue =
             target->Target->GetMakefile()->GetDefinition(propertyName);
           if (propertyValue &&
               cmIsOn(cmGeneratorExpression::Evaluate(
-                propertyValue, target->GetLocalGenerator(), i))) {
+                *propertyValue, target->GetLocalGenerator(), i))) {
             activeConfigs.insert(i);
           }
         }
@@ -693,9 +693,7 @@ std::set<std::string> cmGlobalVisualStudio7Generator::IsPartOfDefaultBuild(
   }
   // inspect EXCLUDE_FROM_DEFAULT_BUILD[_<CONFIG>] properties
   for (std::string const& i : configs) {
-    const char* propertyValue =
-      target->GetFeature("EXCLUDE_FROM_DEFAULT_BUILD", i);
-    if (cmIsOff(propertyValue)) {
+    if (cmIsOff(target->GetFeature("EXCLUDE_FROM_DEFAULT_BUILD", i))) {
       activeConfigs.insert(i);
     }
   }
diff --git a/Source/cmGlobalVisualStudio7Generator.h b/Source/cmGlobalVisualStudio7Generator.h
index 6cc1cf8..148762e 100644
--- a/Source/cmGlobalVisualStudio7Generator.h
+++ b/Source/cmGlobalVisualStudio7Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio7Generator_h
-#define cmGlobalVisualStudio7Generator_h
+#pragma once
 
 #include <memory>
 
@@ -174,5 +173,3 @@ private:
 };
 
 #define CMAKE_CHECK_BUILD_SYSTEM_TARGET "ZERO_CHECK"
-
-#endif
diff --git a/Source/cmGlobalVisualStudio8Generator.cxx b/Source/cmGlobalVisualStudio8Generator.cxx
index 29ca154..fcdfc50 100644
--- a/Source/cmGlobalVisualStudio8Generator.cxx
+++ b/Source/cmGlobalVisualStudio8Generator.cxx
@@ -325,7 +325,7 @@ void cmGlobalVisualStudio8Generator::WriteProjectDepends(
   TargetDependSet const& unordered = this->GetTargetDirectDepends(gt);
   OrderedTargetDependSet depends(unordered, std::string());
   for (cmTargetDepend const& i : depends) {
-    if (i->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!i->IsInBuildSystem()) {
       continue;
     }
     std::string guid = this->GetGUID(i->GetName());
@@ -341,7 +341,7 @@ bool cmGlobalVisualStudio8Generator::NeedLinkLibraryDependencies(
     if (cmGeneratorTarget* depTarget =
           target->GetLocalGenerator()->FindGeneratorTargetToUse(
             ui.Value.first)) {
-      if (depTarget->GetType() != cmStateEnums::INTERFACE_LIBRARY &&
+      if (depTarget->IsInBuildSystem() &&
           depTarget->GetProperty("EXTERNAL_MSPROJECT")) {
         // This utility dependency names an external .vcproj target.
         // We use LinkLibraryDependencies="true" to link to it without
diff --git a/Source/cmGlobalVisualStudio8Generator.h b/Source/cmGlobalVisualStudio8Generator.h
index 6ce67d3..96e3553 100644
--- a/Source/cmGlobalVisualStudio8Generator.h
+++ b/Source/cmGlobalVisualStudio8Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio8Generator_h
-#define cmGlobalVisualStudio8Generator_h
+#pragma once
 
 #include "cmGlobalVisualStudio71Generator.h"
 
@@ -78,4 +77,3 @@ protected:
   std::string Name;
   std::string WindowsCEVersion;
 };
-#endif
diff --git a/Source/cmGlobalVisualStudio9Generator.h b/Source/cmGlobalVisualStudio9Generator.h
index 53318a6..6f4d159 100644
--- a/Source/cmGlobalVisualStudio9Generator.h
+++ b/Source/cmGlobalVisualStudio9Generator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudio9Generator_h
-#define cmGlobalVisualStudio9Generator_h
+#pragma once
 
 #include <memory>
 
@@ -38,4 +37,3 @@ private:
   class Factory;
   friend class Factory;
 };
-#endif
diff --git a/Source/cmGlobalVisualStudioGenerator.cxx b/Source/cmGlobalVisualStudioGenerator.cxx
index c688da2..001d876 100644
--- a/Source/cmGlobalVisualStudioGenerator.cxx
+++ b/Source/cmGlobalVisualStudioGenerator.cxx
@@ -368,7 +368,7 @@ cmGlobalVisualStudioGenerator::GetTargetLinkClosure(cmGeneratorTarget* target)
 void cmGlobalVisualStudioGenerator::FollowLinkDepends(
   const cmGeneratorTarget* target, std::set<const cmGeneratorTarget*>& linked)
 {
-  if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+  if (!target->IsInBuildSystem()) {
     return;
   }
   if (linked.insert(target).second &&
@@ -509,7 +509,7 @@ std::string cmGlobalVisualStudioGenerator::GetStartupProjectName(
   cmLocalGenerator const* root) const
 {
   cmProp n = root->GetMakefile()->GetProperty("VS_STARTUP_PROJECT");
-  if (n && !n->empty()) {
+  if (cmNonempty(n)) {
     std::string startup = *n;
     if (this->FindTarget(startup)) {
       return startup;
@@ -810,7 +810,7 @@ bool cmGlobalVisualStudioGenerator::TargetIsFortranOnly(
   // a target with none of its own sources, e.g. when also using
   // object libraries.
   cmProp linkLang = gt->GetProperty("LINKER_LANGUAGE");
-  if (linkLang && !linkLang->empty()) {
+  if (cmNonempty(linkLang)) {
     languages.insert(*linkLang);
   }
 
diff --git a/Source/cmGlobalVisualStudioGenerator.h b/Source/cmGlobalVisualStudioGenerator.h
index 29a5c2c..3c46408 100644
--- a/Source/cmGlobalVisualStudioGenerator.h
+++ b/Source/cmGlobalVisualStudioGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudioGenerator_h
-#define cmGlobalVisualStudioGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -224,5 +223,3 @@ public:
   OrderedTargetDependSet(TargetDependSet const&, std::string const& first);
   OrderedTargetDependSet(TargetSet const&, std::string const& first);
 };
-
-#endif
diff --git a/Source/cmGlobalVisualStudioVersionedGenerator.cxx b/Source/cmGlobalVisualStudioVersionedGenerator.cxx
index 605dc8b..4b877ce 100644
--- a/Source/cmGlobalVisualStudioVersionedGenerator.cxx
+++ b/Source/cmGlobalVisualStudioVersionedGenerator.cxx
@@ -100,6 +100,24 @@ static const char* VSVersionToToolset(
   return "";
 }
 
+static const char* VSVersionToAndroidToolset(
+  cmGlobalVisualStudioGenerator::VSVersion v)
+{
+  switch (v) {
+    case cmGlobalVisualStudioGenerator::VS9:
+    case cmGlobalVisualStudioGenerator::VS10:
+    case cmGlobalVisualStudioGenerator::VS11:
+    case cmGlobalVisualStudioGenerator::VS12:
+      return "";
+    case cmGlobalVisualStudioGenerator::VS14:
+      return "Clang_3_8";
+    case cmGlobalVisualStudioGenerator::VS15:
+    case cmGlobalVisualStudioGenerator::VS16:
+      return "Clang_5_0";
+  }
+  return "";
+}
+
 static const char vs15generatorName[] = "Visual Studio 15 2017";
 
 // Map generator name without year to name with year.
@@ -284,6 +302,7 @@ cmGlobalVisualStudioVersionedGenerator::cmGlobalVisualStudioVersionedGenerator(
   this->Version = version;
   this->ExpressEdition = false;
   this->DefaultPlatformToolset = VSVersionToToolset(this->Version);
+  this->DefaultAndroidToolset = VSVersionToAndroidToolset(this->Version);
   this->DefaultCLFlagTableName = VSVersionToToolset(this->Version);
   this->DefaultCSharpFlagTableName = VSVersionToToolset(this->Version);
   this->DefaultLinkFlagTableName = VSVersionToToolset(this->Version);
@@ -408,6 +427,25 @@ bool cmGlobalVisualStudioVersionedGenerator::IsStdOutEncodingSupported() const
           vsInstanceVersion > vsInstanceVersion16_7_P2);
 }
 
+const char*
+cmGlobalVisualStudioVersionedGenerator::GetAndroidApplicationTypeRevision()
+  const
+{
+  switch (this->Version) {
+    case cmGlobalVisualStudioGenerator::VS9:
+    case cmGlobalVisualStudioGenerator::VS10:
+    case cmGlobalVisualStudioGenerator::VS11:
+    case cmGlobalVisualStudioGenerator::VS12:
+      return "";
+    case cmGlobalVisualStudioGenerator::VS14:
+      return "2.0";
+    case cmGlobalVisualStudioGenerator::VS15:
+    case cmGlobalVisualStudioGenerator::VS16:
+      return "3.0";
+  }
+  return "";
+}
+
 std::string cmGlobalVisualStudioVersionedGenerator::GetAuxiliaryToolset() const
 {
   const char* version = this->GetPlatformToolsetVersion();
@@ -502,8 +540,8 @@ bool cmGlobalVisualStudioVersionedGenerator::IsWin81SDKInstalled() const
   return false;
 }
 
-std::string cmGlobalVisualStudioVersionedGenerator::GetWindows10SDKMaxVersion()
-  const
+std::string cmGlobalVisualStudioVersionedGenerator::GetWindows10SDKMaxVersion(
+  cmMakefile*) const
 {
   return std::string();
 }
diff --git a/Source/cmGlobalVisualStudioVersionedGenerator.h b/Source/cmGlobalVisualStudioVersionedGenerator.h
index cbd3ba7..af09cbd 100644
--- a/Source/cmGlobalVisualStudioVersionedGenerator.h
+++ b/Source/cmGlobalVisualStudioVersionedGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalVisualStudioVersionedGenerator_h
-#define cmGlobalVisualStudioVersionedGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -36,6 +35,8 @@ public:
 
   bool IsStdOutEncodingSupported() const override;
 
+  const char* GetAndroidApplicationTypeRevision() const override;
+
 protected:
   cmGlobalVisualStudioVersionedGenerator(
     VSVersion version, cmake* cm, const std::string& name,
@@ -55,7 +56,7 @@ protected:
   // Check for a Win 8 SDK known to the registry or VS installer tool.
   bool IsWin81SDKInstalled() const;
 
-  std::string GetWindows10SDKMaxVersion() const override;
+  std::string GetWindows10SDKMaxVersion(cmMakefile*) const override;
 
   std::string FindMSBuildCommand() override;
   std::string FindDevEnvCommand() override;
@@ -67,4 +68,3 @@ private:
   friend class Factory16;
   mutable cmVSSetupAPIHelper vsSetupAPIHelper;
 };
-#endif
diff --git a/Source/cmGlobalWatcomWMakeGenerator.h b/Source/cmGlobalWatcomWMakeGenerator.h
index c47127f..da39d3f 100644
--- a/Source/cmGlobalWatcomWMakeGenerator.h
+++ b/Source/cmGlobalWatcomWMakeGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalWatcomWMakeGenerator_h
-#define cmGlobalWatcomWMakeGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -64,5 +63,3 @@ protected:
 
   void PrintBuildCommandAdvice(std::ostream& os, int jobs) const override;
 };
-
-#endif
diff --git a/Source/cmGlobalXCodeGenerator.cxx b/Source/cmGlobalXCodeGenerator.cxx
index b28395a..2f27128 100644
--- a/Source/cmGlobalXCodeGenerator.cxx
+++ b/Source/cmGlobalXCodeGenerator.cxx
@@ -173,6 +173,7 @@ cmGlobalXCodeGenerator::cmGlobalXCodeGenerator(
 
   this->RootObject = nullptr;
   this->MainGroupChildren = nullptr;
+  this->FrameworkGroup = nullptr;
   this->CurrentMakefile = nullptr;
   this->CurrentLocalGenerator = nullptr;
   this->XcodeBuildCommandInitialized = false;
@@ -423,37 +424,6 @@ void cmGlobalXCodeGenerator::AddExtraIDETargets()
   }
 }
 
-void cmGlobalXCodeGenerator::ComputeTargetOrder()
-{
-  size_t index = 0;
-  auto const& lgens = this->GetLocalGenerators();
-  for (auto const& lgen : lgens) {
-    const auto& targets = lgen->GetGeneratorTargets();
-    for (const auto& gt : targets) {
-      this->ComputeTargetOrder(gt.get(), index);
-    }
-  }
-  assert(index == this->TargetOrderIndex.size());
-}
-
-void cmGlobalXCodeGenerator::ComputeTargetOrder(cmGeneratorTarget const* gt,
-                                                size_t& index)
-{
-  std::map<cmGeneratorTarget const*, size_t>::value_type value(gt, 0);
-  auto insertion = this->TargetOrderIndex.insert(value);
-  if (!insertion.second) {
-    return;
-  }
-  auto entry = insertion.first;
-
-  auto& deps = this->GetTargetDirectDepends(gt);
-  for (auto& d : deps) {
-    this->ComputeTargetOrder(d, index);
-  }
-
-  entry->second = index++;
-}
-
 void cmGlobalXCodeGenerator::Generate()
 {
   this->cmGlobalGenerator::Generate();
@@ -461,8 +431,6 @@ void cmGlobalXCodeGenerator::Generate()
     return;
   }
 
-  this->ComputeTargetOrder();
-
   for (auto keyVal : this->ProjectMap) {
     cmLocalGenerator* root = keyVal.second[0];
 
@@ -476,6 +444,9 @@ void cmGlobalXCodeGenerator::Generate()
       }
     }
 
+    // cache the enabled languages for source file type queries
+    this->GetEnabledLanguages(this->EnabledLangs);
+
     this->SetGenerationRoot(root);
     // now create the project
     this->OutputXCodeProject(root, keyVal.second);
@@ -673,6 +644,9 @@ void cmGlobalXCodeGenerator::ClearXCodeObjects()
   this->GroupNameMap.clear();
   this->TargetGroup.clear();
   this->FileRefs.clear();
+  this->ExternalLibRefs.clear();
+  this->FileRefToBuildFileMap.clear();
+  this->CommandsVisited.clear();
 }
 
 void cmGlobalXCodeGenerator::addObject(std::unique_ptr<cmXCodeObject> obj)
@@ -741,21 +715,28 @@ std::string GetGroupMapKeyFromPath(cmGeneratorTarget* target,
   return key;
 }
 
-cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeSourceFileFromPath(
+cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeBuildFileFromPath(
   const std::string& fullpath, cmGeneratorTarget* target,
   const std::string& lang, cmSourceFile* sf)
 {
   // Using a map and the full path guarantees that we will always get the same
-  // fileRef object for any given full path.
-  //
+  // fileRef object for any given full path. Same goes for the buildFile
+  // object.
   cmXCodeObject* fileRef =
     this->CreateXCodeFileReferenceFromPath(fullpath, target, lang, sf);
-
-  cmXCodeObject* buildFile = this->CreateObject(cmXCodeObject::PBXBuildFile);
-  buildFile->SetComment(fileRef->GetComment());
-  buildFile->AddAttribute("fileRef", this->CreateObjectReference(fileRef));
-
-  return buildFile;
+  if (fileRef) {
+    auto it = this->FileRefToBuildFileMap.find(fileRef);
+    if (it == this->FileRefToBuildFileMap.end()) {
+      cmXCodeObject* buildFile =
+        this->CreateObject(cmXCodeObject::PBXBuildFile);
+      buildFile->SetComment(fileRef->GetComment());
+      buildFile->AddAttribute("fileRef", this->CreateObjectReference(fileRef));
+      this->FileRefToBuildFileMap[fileRef] = buildFile;
+      return buildFile;
+    }
+    return it->second;
+  }
+  return nullptr;
 }
 
 class XCodeGeneratorExpressionInterpreter
@@ -827,6 +808,14 @@ cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeSourceFile(
     default:
       break;
   }
+
+  // explicitly add the explicit language flag before any other flag
+  // this way backwards compatibility with user flags is maintained
+  if (sf->GetProperty("LANGUAGE")) {
+    this->CurrentLocalGenerator->AppendFeatureOptions(flags, lang,
+                                                      "EXPLICIT_LANGUAGE");
+  }
+
   const std::string COMPILE_FLAGS("COMPILE_FLAGS");
   if (cmProp cflags = sf->GetProperty(COMPILE_FLAGS)) {
     lg->AppendFlags(flags, genexInterpreter.Evaluate(*cflags, COMPILE_FLAGS));
@@ -869,7 +858,7 @@ cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeSourceFile(
   lg->AppendFlags(flags, lg->GetIncludeFlags(includes, gtgt, lang, true));
 
   cmXCodeObject* buildFile =
-    this->CreateXCodeSourceFileFromPath(sf->ResolveFullPath(), gtgt, lang, sf);
+    this->CreateXCodeBuildFileFromPath(sf->ResolveFullPath(), gtgt, lang, sf);
 
   cmXCodeObject* settings = this->CreateObject(cmXCodeObject::ATTRIBUTE_GROUP);
   settings->AddAttributeIfNotEmpty("COMPILER_FLAGS",
@@ -905,7 +894,9 @@ cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeSourceFile(
 
   settings->AddAttributeIfNotEmpty("ATTRIBUTES", attrs);
 
-  buildFile->AddAttributeIfNotEmpty("settings", settings);
+  if (buildFile) {
+    buildFile->AddAttributeIfNotEmpty("settings", settings);
+  }
   return buildFile;
 }
 
@@ -922,14 +913,45 @@ void cmGlobalXCodeGenerator::AddXCodeProjBuildRule(
   }
 }
 
-std::string GetSourcecodeValueFromFileExtension(const std::string& _ext,
-                                                const std::string& lang,
-                                                bool& keepLastKnownFileType)
+namespace {
+
+bool IsLinkPhaseLibraryExtension(const std::string& fileExt)
+{
+  // Empty file extension is a special case for paths to framework's
+  // internal binary which could be MyFw.framework/Versions/*/MyFw
+  return (fileExt == ".framework" || fileExt == ".a" || fileExt == ".o" ||
+          fileExt == ".dylib" || fileExt == ".tbd" || fileExt.empty());
+}
+bool IsLibraryType(const std::string& fileType)
+{
+  return (fileType == "wrapper.framework" || fileType == "archive.ar" ||
+          fileType == "compiled.mach-o.objfile" ||
+          fileType == "compiled.mach-o.dylib" ||
+          fileType == "compiled.mach-o.executable" ||
+          fileType == "sourcecode.text-based-dylib-definition");
+}
+
+std::string GetDirectoryValueFromFileExtension(const std::string& dirExt)
+{
+  std::string ext = cmSystemTools::LowerCase(dirExt);
+  if (ext == "framework") {
+    return "wrapper.framework";
+  }
+  if (ext == "xcassets") {
+    return "folder.assetcatalog";
+  }
+  return "folder";
+}
+
+std::string GetSourcecodeValueFromFileExtension(
+  const std::string& _ext, const std::string& lang,
+  bool& keepLastKnownFileType, const std::vector<std::string>& enabled_langs)
 {
   std::string ext = cmSystemTools::LowerCase(_ext);
   std::string sourcecode = "sourcecode";
 
   if (ext == "o") {
+    keepLastKnownFileType = true;
     sourcecode = "compiled.mach-o.objfile";
   } else if (ext == "xctest") {
     sourcecode = "wrapper.cfbundle";
@@ -939,9 +961,9 @@ std::string GetSourcecodeValueFromFileExtension(const std::string& _ext,
   } else if (ext == "storyboard") {
     keepLastKnownFileType = true;
     sourcecode = "file.storyboard";
-  } else if (ext == "mm") {
+  } else if (ext == "mm" && !cm::contains(enabled_langs, "OBJCXX")) {
     sourcecode += ".cpp.objcpp";
-  } else if (ext == "m") {
+  } else if (ext == "m" && !cm::contains(enabled_langs, "OBJC")) {
     sourcecode += ".c.objc";
   } else if (ext == "swift") {
     sourcecode += ".swift";
@@ -973,6 +995,20 @@ std::string GetSourcecodeValueFromFileExtension(const std::string& _ext,
     sourcecode += ".metal";
   } else if (ext == "mig") {
     sourcecode += ".mig";
+  } else if (ext == "tbd") {
+    sourcecode += ".text-based-dylib-definition";
+  } else if (ext == "a") {
+    keepLastKnownFileType = true;
+    sourcecode = "archive.ar";
+  } else if (ext == "dylib") {
+    keepLastKnownFileType = true;
+    sourcecode = "compiled.mach-o.dylib";
+  } else if (ext == "framework") {
+    keepLastKnownFileType = true;
+    sourcecode = "wrapper.framework";
+  } else if (ext == "xcassets") {
+    keepLastKnownFileType = true;
+    sourcecode = "folder.assetcatalog";
   }
   // else
   //  {
@@ -985,24 +1021,51 @@ std::string GetSourcecodeValueFromFileExtension(const std::string& _ext,
   return sourcecode;
 }
 
+// If the file has no extension it's either a raw executable or might
+// be a direct reference to a binary within a framework (bad practice!).
+// This is where we change the path to point to the framework directory.
+// .tbd files also can be located in SDK frameworks (they are
+// placeholders for actual libraries shipped with the OS)
+std::string GetLibraryOrFrameworkPath(const std::string& path)
+{
+  auto ext = cmSystemTools::GetFilenameLastExtension(path);
+  if (ext.empty() || ext == ".tbd") {
+    auto name = cmSystemTools::GetFilenameWithoutExtension(path);
+    // Check for iOS framework structure:
+    //    FwName.framework/FwName (and also on macOS where FwName lib is a
+    //    symlink)
+    auto parentDir = cmSystemTools::GetParentDirectory(path);
+    auto parentName = cmSystemTools::GetFilenameWithoutExtension(parentDir);
+    ext = cmSystemTools::GetFilenameLastExtension(parentDir);
+    if (ext == ".framework" && name == parentName) {
+      return parentDir;
+    }
+    // Check for macOS framework structure:
+    //    FwName.framework/Versions/*/FwName
+    std::vector<std::string> components;
+    cmSystemTools::SplitPath(path, components);
+    if (components.size() > 3 &&
+        components[components.size() - 3] == "Versions") {
+      ext = cmSystemTools::GetFilenameLastExtension(
+        components[components.size() - 4]);
+      parentName = cmSystemTools::GetFilenameWithoutExtension(
+        components[components.size() - 4]);
+      if (ext == ".framework" && name == parentName) {
+        components.erase(components.begin() + components.size() - 3,
+                         components.end());
+        return cmSystemTools::JoinPath(components);
+      }
+    }
+  }
+  return path;
+}
+
+} // anonymous
+
 cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeFileReferenceFromPath(
   const std::string& fullpath, cmGeneratorTarget* target,
   const std::string& lang, cmSourceFile* sf)
 {
-  std::string key = GetGroupMapKeyFromPath(target, fullpath);
-  cmXCodeObject* fileRef = this->FileRefs[key];
-  if (!fileRef) {
-    fileRef = this->CreateObject(cmXCodeObject::PBXFileReference);
-    fileRef->SetComment(fullpath);
-    this->FileRefs[key] = fileRef;
-  }
-  cmXCodeObject* group = this->GroupMap[key];
-  cmXCodeObject* children = group->GetObject("children");
-  if (!children->HasObject(fileRef)) {
-    children->AddObject(fileRef);
-  }
-  fileRef->AddAttribute("fileEncoding", this->CreateString("4"));
-
   bool useLastKnownFileType = false;
   std::string fileType;
   if (sf) {
@@ -1013,38 +1076,76 @@ cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeFileReferenceFromPath(
       fileType = *l;
     }
   }
+  // Make a copy so that we can override it later
+  std::string path = fullpath;
+  // Compute the extension without leading '.'.
+  std::string ext = cmSystemTools::GetFilenameLastExtension(path);
+  if (!ext.empty()) {
+    ext = ext.substr(1);
+  }
   if (fileType.empty()) {
-    // Compute the extension without leading '.'.
-    std::string ext = cmSystemTools::GetFilenameLastExtension(fullpath);
+    path = GetLibraryOrFrameworkPath(path);
+    ext = cmSystemTools::GetFilenameLastExtension(path);
     if (!ext.empty()) {
       ext = ext.substr(1);
     }
-
     // If fullpath references a directory, then we need to specify
     // lastKnownFileType as folder in order for Xcode to be able to
     // open the contents of the folder.
     // (Xcode 4.6 does not like explicitFileType=folder).
-    if (cmSystemTools::FileIsDirectory(fullpath)) {
-      fileType = (ext == "xcassets" ? "folder.assetcatalog" : "folder");
+    if (cmSystemTools::FileIsDirectory(path)) {
+      fileType = GetDirectoryValueFromFileExtension(ext);
       useLastKnownFileType = true;
     } else {
-      fileType =
-        GetSourcecodeValueFromFileExtension(ext, lang, useLastKnownFileType);
+      if (ext.empty() && !sf) {
+        // Special case for executable or library without extension
+        // that is not a source file. We can't tell which without reading
+        // its Mach-O header, but the file might not exist yet, so we
+        // have to pick one here.
+        useLastKnownFileType = true;
+        fileType = "compiled.mach-o.executable";
+      } else {
+        fileType = GetSourcecodeValueFromFileExtension(
+          ext, lang, useLastKnownFileType, this->EnabledLangs);
+      }
     }
   }
 
+  std::string key = GetGroupMapKeyFromPath(target, path);
+  cmXCodeObject* fileRef = this->FileRefs[key];
+  if (!fileRef) {
+    fileRef = this->CreateObject(cmXCodeObject::PBXFileReference);
+    fileRef->SetComment(path);
+    this->FileRefs[key] = fileRef;
+  }
+  fileRef->AddAttribute("fileEncoding", this->CreateString("4"));
   fileRef->AddAttribute(useLastKnownFileType ? "lastKnownFileType"
                                              : "explicitFileType",
                         this->CreateString(fileType));
-
   // Store the file path relative to the top of the source tree.
-  std::string path = this->RelativeToSource(fullpath);
+  if (!IsLibraryType(fileType)) {
+    path = this->RelativeToSource(path);
+  }
   std::string name = cmSystemTools::GetFilenameName(path);
   const char* sourceTree =
     cmSystemTools::FileIsFullPath(path) ? "<absolute>" : "SOURCE_ROOT";
   fileRef->AddAttribute("name", this->CreateString(name));
   fileRef->AddAttribute("path", this->CreateString(path));
   fileRef->AddAttribute("sourceTree", this->CreateString(sourceTree));
+
+  cmXCodeObject* group = this->GroupMap[key];
+  if (!group && IsLibraryType(fileType)) {
+    group = this->FrameworkGroup;
+    this->GroupMap[key] = group;
+  }
+  if (!group) {
+    cmSystemTools::Error("Could not find a PBX group for " + key);
+    return nullptr;
+  }
+  cmXCodeObject* children = group->GetAttribute("children");
+  if (!children->HasObject(fileRef)) {
+    children->AddObject(fileRef);
+  }
   return fileRef;
 }
 
@@ -1077,11 +1178,8 @@ void cmGlobalXCodeGenerator::SetCurrentLocalGenerator(cmLocalGenerator* gen)
   this->CurrentMakefile = gen->GetMakefile();
 
   // Select the current set of configuration types.
-  this->CurrentConfigurationTypes.clear();
-  this->CurrentMakefile->GetConfigurations(this->CurrentConfigurationTypes);
-  if (this->CurrentConfigurationTypes.empty()) {
-    this->CurrentConfigurationTypes.emplace_back();
-  }
+  this->CurrentConfigurationTypes =
+    this->CurrentMakefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 }
 
 struct cmSourceFilePathCompare
@@ -1112,12 +1210,8 @@ bool cmGlobalXCodeGenerator::CreateXCodeTargets(
   cmLocalGenerator* gen, std::vector<cmXCodeObject*>& targets)
 {
   this->SetCurrentLocalGenerator(gen);
-  std::vector<cmGeneratorTarget*> gts;
-  cm::append(gts, this->CurrentLocalGenerator->GetGeneratorTargets());
-  std::sort(gts.begin(), gts.end(),
-            [this](cmGeneratorTarget const* l, cmGeneratorTarget const* r) {
-              return this->TargetOrderIndex[l] < this->TargetOrderIndex[r];
-            });
+  std::vector<cmGeneratorTarget*> gts =
+    this->GetLocalGeneratorTargetsInOrder(gen);
   for (auto gtgt : gts) {
     if (!this->CreateXCodeTarget(gtgt, targets)) {
       return false;
@@ -1137,11 +1231,22 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
     return true;
   }
 
-  if (gtgt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+  if (!gtgt->IsInBuildSystem()) {
     return true;
   }
 
+  auto& gtgt_visited = this->CommandsVisited[gtgt];
+  auto& deps = this->GetTargetDirectDepends(gtgt);
+  for (auto& d : deps) {
+    // Take the union of visited source files of custom commands so far.
+    // ComputeTargetOrder ensures our dependencies already visited their
+    // custom commands and updated CommandsVisited.
+    auto& dep_visited = this->CommandsVisited[d];
+    gtgt_visited.insert(dep_visited.begin(), dep_visited.end());
+  }
+
   if (gtgt->GetType() == cmStateEnums::UTILITY ||
+      gtgt->GetType() == cmStateEnums::INTERFACE_LIBRARY ||
       gtgt->GetType() == cmStateEnums::GLOBAL_TARGET) {
     cmXCodeObject* t = this->CreateUtilityTarget(gtgt);
     if (!t) {
@@ -1152,23 +1257,24 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
   }
 
   // organize the sources
-  std::vector<cmSourceFile*> classes;
-  if (!gtgt->GetConfigCommonSourceFiles(classes)) {
+  std::vector<cmSourceFile*> commonSourceFiles;
+  if (!gtgt->GetConfigCommonSourceFiles(commonSourceFiles)) {
     return false;
   }
 
   // Add CMakeLists.txt file for user convenience.
-  this->AddXCodeProjBuildRule(gtgt, classes);
+  this->AddXCodeProjBuildRule(gtgt, commonSourceFiles);
 
   // Add the Info.plist we are about to generate for an App Bundle.
   if (gtgt->GetPropertyAsBool("MACOSX_BUNDLE")) {
     std::string plist = this->ComputeInfoPListLocation(gtgt);
     cmSourceFile* sf = gtgt->Makefile->GetOrCreateSource(
       plist, true, cmSourceFileLocationKind::Known);
-    classes.push_back(sf);
+    commonSourceFiles.push_back(sf);
   }
 
-  std::sort(classes.begin(), classes.end(), cmSourceFilePathCompare());
+  std::sort(commonSourceFiles.begin(), commonSourceFiles.end(),
+            cmSourceFilePathCompare());
 
   gtgt->ComputeObjectMapping();
 
@@ -1176,16 +1282,20 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
   std::vector<cmXCodeObject*> headerFiles;
   std::vector<cmXCodeObject*> resourceFiles;
   std::vector<cmXCodeObject*> sourceFiles;
-  for (auto sourceFile : classes) {
+  for (auto sourceFile : commonSourceFiles) {
     cmXCodeObject* xsf = this->CreateXCodeSourceFile(
       this->CurrentLocalGenerator, sourceFile, gtgt);
-    cmXCodeObject* fr = xsf->GetObject("fileRef");
-    cmXCodeObject* filetype = fr->GetObject()->GetObject("explicitFileType");
+    cmXCodeObject* fr = xsf->GetAttribute("fileRef");
+    cmXCodeObject* filetype =
+      fr->GetObject()->GetAttribute("explicitFileType");
+    if (!filetype) {
+      filetype = fr->GetObject()->GetAttribute("lastKnownFileType");
+    }
 
     cmGeneratorTarget::SourceFileFlags tsFlags =
       gtgt->GetTargetSourceFileFlags(sourceFile);
 
-    if (filetype && filetype->GetString() == "compiled.mach-o.objfile") {
+    if (filetype && IsLibraryType(filetype->GetString())) {
       if (sourceFile->GetObjectLibrary().empty()) {
         externalObjFiles.push_back(xsf);
       }
@@ -1275,7 +1385,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
     using mapOfVectorOfSourceFiles =
       std::map<std::string, std::vector<cmSourceFile*>>;
     mapOfVectorOfSourceFiles bundleFiles;
-    for (auto sourceFile : classes) {
+    for (auto sourceFile : commonSourceFiles) {
       cmGeneratorTarget::SourceFileFlags tsFlags =
         gtgt->GetTargetSourceFileFlags(sourceFile);
       if (tsFlags.Type == cmGeneratorTarget::SourceFileTypeMacContent) {
@@ -1323,7 +1433,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
     using mapOfVectorOfSourceFiles =
       std::map<std::string, std::vector<cmSourceFile*>>;
     mapOfVectorOfSourceFiles bundleFiles;
-    for (auto sourceFile : classes) {
+    for (auto sourceFile : commonSourceFiles) {
       cmGeneratorTarget::SourceFileFlags tsFlags =
         gtgt->GetTargetSourceFileFlags(sourceFile);
       if (tsFlags.Type == cmGeneratorTarget::SourceFileTypeDeepResource) {
@@ -1353,22 +1463,20 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
     }
   }
 
-  // create framework build phase
+  // always create framework build phase
   cmXCodeObject* frameworkBuildPhase = nullptr;
-  if (!externalObjFiles.empty()) {
-    frameworkBuildPhase =
-      this->CreateObject(cmXCodeObject::PBXFrameworksBuildPhase);
-    frameworkBuildPhase->SetComment("Frameworks");
-    frameworkBuildPhase->AddAttribute("buildActionMask",
-                                      this->CreateString("2147483647"));
-    buildFiles = this->CreateObject(cmXCodeObject::OBJECT_LIST);
-    frameworkBuildPhase->AddAttribute("files", buildFiles);
-    for (auto& externalObjFile : externalObjFiles) {
-      buildFiles->AddObject(externalObjFile);
-    }
-    frameworkBuildPhase->AddAttribute("runOnlyForDeploymentPostprocessing",
-                                      this->CreateString("0"));
-  }
+  frameworkBuildPhase =
+    this->CreateObject(cmXCodeObject::PBXFrameworksBuildPhase);
+  frameworkBuildPhase->SetComment("Frameworks");
+  frameworkBuildPhase->AddAttribute("buildActionMask",
+                                    this->CreateString("2147483647"));
+  buildFiles = this->CreateObject(cmXCodeObject::OBJECT_LIST);
+  frameworkBuildPhase->AddAttribute("files", buildFiles);
+  for (auto& externalObjFile : externalObjFiles) {
+    buildFiles->AddObject(externalObjFile);
+  }
+  frameworkBuildPhase->AddAttribute("runOnlyForDeploymentPostprocessing",
+                                    this->CreateString("0"));
 
   // create list of build phases and create the Xcode target
   cmXCodeObject* buildPhases = this->CreateObject(cmXCodeObject::OBJECT_LIST);
@@ -1494,8 +1602,9 @@ void cmGlobalXCodeGenerator::CreateCustomCommands(
   }
   // add all the sources
   std::vector<cmCustomCommand> commands;
+  auto& visited = this->CommandsVisited[gtgt];
   for (auto sourceFile : classes) {
-    if (sourceFile->GetCustomCommand()) {
+    if (sourceFile->GetCustomCommand() && visited.insert(sourceFile).second) {
       commands.push_back(*sourceFile->GetCustomCommand());
     }
   }
@@ -1705,6 +1814,15 @@ void cmGlobalXCodeGenerator::CreateCustomRulesMakefile(
   for (auto const& command : commands) {
     cmCustomCommandGenerator ccg(command, configName,
                                  this->CurrentLocalGenerator);
+    std::vector<std::string> realDepends;
+    realDepends.reserve(ccg.GetDepends().size());
+    for (auto const& d : ccg.GetDepends()) {
+      std::string dep;
+      if (this->CurrentLocalGenerator->GetRealDependency(d, configName, dep)) {
+        realDepends.emplace_back(std::move(dep));
+      }
+    }
+
     if (ccg.GetNumberOfCommands() > 0) {
       makefileStream << "\n";
       const std::vector<std::string>& outputs = ccg.GetOutputs();
@@ -1720,12 +1838,8 @@ void cmGlobalXCodeGenerator::CreateCustomRulesMakefile(
         // There are no outputs.  Use the generated force rule name.
         makefileStream << tname[&ccg.GetCC()] << ": ";
       }
-      for (auto const& d : ccg.GetDepends()) {
-        std::string dep;
-        if (this->CurrentLocalGenerator->GetRealDependency(d, configName,
-                                                           dep)) {
-          makefileStream << "\\\n" << this->ConvertToRelativeForMake(dep);
-        }
+      for (auto const& dep : realDepends) {
+        makefileStream << "\\\n" << this->ConvertToRelativeForMake(dep);
       }
       makefileStream << "\n";
 
@@ -1754,6 +1868,17 @@ void cmGlobalXCodeGenerator::CreateCustomRulesMakefile(
         ccg.AppendArguments(c, cmd);
         makefileStream << "\t" << cmd << "\n";
       }
+
+      // Symbolic inputs are not expected to exist, so add dummy rules.
+      for (auto const& dep : realDepends) {
+        if (cmSourceFile* dsf =
+              target->GetLocalGenerator()->GetMakefile()->GetSource(
+                dep, cmSourceFileLocationKind::Known)) {
+          if (dsf->GetPropertyAsBool("SYMBOLIC")) {
+            makefileStream << this->ConvertToRelativeForMake(dep) << ":\n";
+          }
+        }
+      }
     }
   }
 }
@@ -1781,7 +1906,7 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmGeneratorTarget* gtgt,
                                                  cmXCodeObject* buildSettings,
                                                  const std::string& configName)
 {
-  if (gtgt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+  if (!gtgt->IsInBuildSystem()) {
     return;
   }
 
@@ -2256,7 +2381,7 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmGeneratorTarget* gtgt,
     if (stdlib.size() > 8) {
       const auto cxxLibrary = stdlib.substr(8);
       if (language == "CXX" ||
-          !buildSettings->GetObject("CLANG_CXX_LIBRARY")) {
+          !buildSettings->GetAttribute("CLANG_CXX_LIBRARY")) {
         buildSettings->AddAttribute("CLANG_CXX_LIBRARY",
                                     this->CreateString(cxxLibrary));
       }
@@ -2278,7 +2403,7 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmGeneratorTarget* gtgt,
     std::string flags = cflags[language] + " " + defFlags;
     if (language == "CXX" || language == "OBJCXX") {
       if (language == "CXX" ||
-          !buildSettings->GetObject("OTHER_CPLUSPLUSFLAGS")) {
+          !buildSettings->GetAttribute("OTHER_CPLUSPLUSFLAGS")) {
         buildSettings->AddAttribute("OTHER_CPLUSPLUSFLAGS",
                                     this->CreateString(flags));
       }
@@ -2286,7 +2411,7 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmGeneratorTarget* gtgt,
       buildSettings->AddAttribute("IFORT_OTHER_FLAGS",
                                   this->CreateString(flags));
     } else if (language == "C" || language == "OBJC") {
-      if (language == "C" || !buildSettings->GetObject("OTHER_CFLAGS")) {
+      if (language == "C" || !buildSettings->GetAttribute("OTHER_CFLAGS")) {
         buildSettings->AddAttribute("OTHER_CFLAGS", this->CreateString(flags));
       }
     } else if (language == "Swift") {
@@ -2472,7 +2597,7 @@ cmXCodeObject* cmGlobalXCodeGenerator::CreateUtilityTarget(
   this->XCodeObjectMap[gtgt] = target;
 
   // Add source files without build rules for editing convenience.
-  if (gtgt->GetType() == cmStateEnums::UTILITY &&
+  if (gtgt->GetType() != cmStateEnums::GLOBAL_TARGET &&
       gtgt->GetName() != CMAKE_CHECK_BUILD_SYSTEM_TARGET) {
     std::vector<cmSourceFile*> sources;
     if (!gtgt->GetConfigCommonSourceFiles(sources)) {
@@ -2614,7 +2739,7 @@ const char* cmGlobalXCodeGenerator::GetTargetProductType(
 cmXCodeObject* cmGlobalXCodeGenerator::CreateXCodeTarget(
   cmGeneratorTarget* gtgt, cmXCodeObject* buildPhases)
 {
-  if (gtgt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+  if (!gtgt->IsInBuildSystem()) {
     return nullptr;
   }
   cmXCodeObject* target = this->CreateObject(cmXCodeObject::PBXNativeTarget);
@@ -2706,7 +2831,7 @@ void cmGlobalXCodeGenerator::AddDependTarget(cmXCodeObject* target,
   targetdep->AddAttribute("targetProxy",
                           this->CreateObjectReference(container));
 
-  cmXCodeObject* depends = target->GetObject("dependencies");
+  cmXCodeObject* depends = target->GetAttribute("dependencies");
   if (!depends) {
     cmSystemTools::Error(
       "target does not have dependencies attribute error..");
@@ -2718,33 +2843,60 @@ void cmGlobalXCodeGenerator::AddDependTarget(cmXCodeObject* target,
 
 void cmGlobalXCodeGenerator::AppendOrAddBuildSetting(cmXCodeObject* settings,
                                                      const char* attribute,
-                                                     const char* value)
+                                                     cmXCodeObject* value)
 {
   if (settings) {
-    cmXCodeObject* attr = settings->GetObject(attribute);
+    cmXCodeObject* attr = settings->GetAttribute(attribute);
     if (!attr) {
-      settings->AddAttribute(attribute, this->CreateString(value));
+      settings->AddAttribute(attribute, value);
     } else {
-      std::string oldValue = cmStrCat(attr->GetString(), ' ', value);
-      attr->SetString(oldValue);
+      if (value->GetType() != cmXCodeObject::OBJECT_LIST &&
+          value->GetType() != cmXCodeObject::STRING) {
+        cmSystemTools::Error("Unsupported value type for appending: " +
+                             std::string(attribute));
+        return;
+      }
+      if (attr->GetType() == cmXCodeObject::OBJECT_LIST) {
+        if (value->GetType() == cmXCodeObject::OBJECT_LIST) {
+          for (auto* obj : value->GetObjectList()) {
+            attr->AddObject(obj);
+          }
+        } else {
+          attr->AddObject(value);
+        }
+      } else if (attr->GetType() == cmXCodeObject::STRING) {
+        if (value->GetType() == cmXCodeObject::OBJECT_LIST) {
+          // Add old value as a list item to new object list
+          // and replace the attribute with the new list
+          value->PrependObject(attr);
+          settings->AddAttribute(attribute, value);
+        } else {
+          std::string newValue =
+            cmStrCat(attr->GetString(), ' ', value->GetString());
+          attr->SetString(newValue);
+        }
+      } else {
+        cmSystemTools::Error("Unsupported attribute type for appending: " +
+                             std::string(attribute));
+      }
     }
   }
 }
 
 void cmGlobalXCodeGenerator::AppendBuildSettingAttribute(
-  cmXCodeObject* target, const char* attribute, const char* value,
+  cmXCodeObject* target, const char* attribute, cmXCodeObject* value,
   const std::string& configName)
 {
   // There are multiple configurations.  Add the setting to the
   // buildSettings of the configuration name given.
   cmXCodeObject* configurationList =
-    target->GetObject("buildConfigurationList")->GetObject();
+    target->GetAttribute("buildConfigurationList")->GetObject();
   cmXCodeObject* buildConfigs =
-    configurationList->GetObject("buildConfigurations");
+    configurationList->GetAttribute("buildConfigurations");
   for (auto obj : buildConfigs->GetObjectList()) {
     if (configName.empty() ||
-        obj->GetObject("name")->GetString() == configName) {
-      cmXCodeObject* settings = obj->GetObject("buildSettings");
+        obj->GetAttribute("name")->GetString() == configName) {
+      cmXCodeObject* settings = obj->GetAttribute("buildSettings");
       this->AppendOrAddBuildSetting(settings, attribute, value);
     }
   }
@@ -2757,7 +2909,7 @@ void cmGlobalXCodeGenerator::AddDependAndLinkInformation(cmXCodeObject* target)
     cmSystemTools::Error("Error no target on xobject\n");
     return;
   }
-  if (gt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+  if (!gt->IsInBuildSystem()) {
     return;
   }
 
@@ -2768,24 +2920,263 @@ void cmGlobalXCodeGenerator::AddDependAndLinkInformation(cmXCodeObject* target)
     }
   }
 
+  // Separate libraries into ones that can be linked using "Link Binary With
+  // Libraries" build phase and the ones that can't. Only targets that build
+  // Apple bundles (.app, .framework, .bundle), executables and dylibs can use
+  // this feature and only targets that represent actual libraries (object,
+  // static, dynamic or bundle, excluding executables) will be used. These are
+  // limitations imposed by CMake use-cases - otherwise a lot of things break.
+  // The rest will be linked using linker flags (OTHER_LDFLAGS setting in Xcode
+  // project).
+  std::map<std::string, std::vector<cmComputeLinkInformation::Item const*>>
+    configItemMap;
+  auto addToLinkerArguments =
+    [&configItemMap](const std::string& configName,
+                     cmComputeLinkInformation::Item const* libItemPtr) {
+      auto& linkVector = configItemMap[configName];
+      if (std::find_if(linkVector.begin(), linkVector.end(),
+                       [libItemPtr](cmComputeLinkInformation::Item const* p) {
+                         return p == libItemPtr;
+                       }) == linkVector.end()) {
+        linkVector.push_back(libItemPtr);
+      }
+    };
+  std::vector<cmComputeLinkInformation::Item const*> linkPhaseTargetVector;
+  std::map<std::string, std::vector<std::string>> targetConfigMap;
+  using ConfigItemPair =
+    std::pair<std::string, cmComputeLinkInformation::Item const*>;
+  std::map<std::string, std::vector<ConfigItemPair>> targetItemMap;
+  std::map<std::string, std::vector<std::string>> targetProductNameMap;
+  bool useLinkPhase = false;
+  bool forceLinkPhase = false;
+  cmProp prop =
+    target->GetTarget()->GetProperty("XCODE_LINK_BUILD_PHASE_MODE");
+  if (prop) {
+    if (*prop == "BUILT_ONLY") {
+      useLinkPhase = true;
+    } else if (*prop == "KNOWN_LOCATION") {
+      useLinkPhase = true;
+      forceLinkPhase = true;
+    } else if (*prop != "NONE") {
+      cmSystemTools::Error("Invalid value for XCODE_LINK_BUILD_PHASE_MODE: " +
+                           *prop);
+      return;
+    }
+  }
+  for (auto const& configName : this->CurrentConfigurationTypes) {
+    cmComputeLinkInformation* cli = gt->GetLinkInformation(configName);
+    if (!cli) {
+      continue;
+    }
+    for (auto const& libItem : cli->GetItems()) {
+      // We want to put only static libraries, dynamic libraries, frameworks
+      // and bundles that are built from targets that are not imported in "Link
+      // Binary With Libraries" build phase. Except if the target property
+      // XCODE_LINK_BUILD_PHASE_MODE is KNOWN_LOCATION then all imported and
+      // non-target libraries will be added as well.
+      if (useLinkPhase &&
+          (gt->GetType() == cmStateEnums::EXECUTABLE ||
+           gt->GetType() == cmStateEnums::SHARED_LIBRARY ||
+           gt->GetType() == cmStateEnums::MODULE_LIBRARY) &&
+          ((libItem.Target &&
+            (!libItem.Target->IsImported() || forceLinkPhase) &&
+            (libItem.Target->GetType() == cmStateEnums::STATIC_LIBRARY ||
+             libItem.Target->GetType() == cmStateEnums::SHARED_LIBRARY ||
+             libItem.Target->GetType() == cmStateEnums::MODULE_LIBRARY ||
+             libItem.Target->GetType() == cmStateEnums::UNKNOWN_LIBRARY)) ||
+           (!libItem.Target && libItem.IsPath && forceLinkPhase))) {
+        std::string libName;
+        bool canUseLinkPhase = true;
+        if (libItem.Target) {
+          if (libItem.Target->GetType() == cmStateEnums::UNKNOWN_LIBRARY) {
+            canUseLinkPhase = canUseLinkPhase && forceLinkPhase;
+          } else {
+            // If a library target uses custom build output directory Xcode
+            // won't pick it up so we have to resort back to linker flags, but
+            // that's OK as long as the custom output dir is absolute path.
+            for (auto const& libConfigName : this->CurrentConfigurationTypes) {
+              canUseLinkPhase = canUseLinkPhase &&
+                libItem.Target->UsesDefaultOutputDir(
+                  libConfigName, cmStateEnums::RuntimeBinaryArtifact);
+            }
+          }
+          libName = libItem.Target->GetName();
+        } else {
+          libName = cmSystemTools::GetFilenameName(libItem.Value.Value);
+          // We don't want all the possible files here, just standard libraries
+          const auto libExt = cmSystemTools::GetFilenameExtension(libName);
+          if (!IsLinkPhaseLibraryExtension(libExt)) {
+            canUseLinkPhase = false;
+          }
+        }
+        if (canUseLinkPhase) {
+          // Add unique configuration name to target-config map for later
+          // checks
+          auto& configVector = targetConfigMap[libName];
+          if (std::find(configVector.begin(), configVector.end(),
+                        configName) == configVector.end()) {
+            configVector.push_back(configName);
+          }
+          // Add a pair of config and item to target-item map
+          auto& itemVector = targetItemMap[libName];
+          itemVector.emplace_back(ConfigItemPair(configName, &libItem));
+          // Add product file-name to a lib-product map
+          auto productName =
+            cmSystemTools::GetFilenameName(libItem.Value.Value);
+          auto& productVector = targetProductNameMap[libName];
+          if (std::find(productVector.begin(), productVector.end(),
+                        productName) == productVector.end()) {
+            productVector.push_back(productName);
+          }
+          continue;
+        }
+      }
+      // Add this library item to a regular linker flag list
+      addToLinkerArguments(configName, &libItem);
+    }
+  }
+
+  // Go through target library map and separate libraries that are linked
+  // in all configurations and produce only single product, from the rest.
+  // Only these will be linked through "Link Binary With Libraries" build
+  // phase.
+  for (auto const& targetLibConfigs : targetConfigMap) {
+    // Add this library to "Link Binary With Libraries" build phase if it's
+    // linked in all configurations and it has only one product name
+    auto& itemVector = targetItemMap[targetLibConfigs.first];
+    auto& productVector = targetProductNameMap[targetLibConfigs.first];
+    if (targetLibConfigs.second == this->CurrentConfigurationTypes &&
+        productVector.size() == 1) {
+      // Add this library to "Link Binary With Libraries" list
+      linkPhaseTargetVector.push_back(itemVector[0].second);
+    } else {
+      for (auto const& libItem : targetItemMap[targetLibConfigs.first]) {
+        // Add this library item to a regular linker flag list
+        addToLinkerArguments(libItem.first, libItem.second);
+      }
+    }
+  }
+
+  // Add libraries to "Link Binary With Libraries" build phase and collect
+  // their search paths. Xcode does not support per-configuration linking
+  // in this build phase so we don't have to do this for each configuration
+  // separately.
+  std::vector<std::string> linkSearchPaths;
+  std::vector<std::string> frameworkSearchPaths;
+  for (auto const& libItem : linkPhaseTargetVector) {
+    // Add target output directory as a library search path
+    std::string linkDir;
+    if (libItem->Target) {
+      linkDir = libItem->Target->GetLocationForBuild();
+    } else {
+      linkDir = libItem->Value.Value;
+    }
+    linkDir = GetLibraryOrFrameworkPath(linkDir);
+    bool isFramework = cmSystemTools::IsPathToFramework(linkDir);
+    linkDir = cmSystemTools::GetParentDirectory(linkDir);
+    if (isFramework) {
+      if (std::find(frameworkSearchPaths.begin(), frameworkSearchPaths.end(),
+                    linkDir) == frameworkSearchPaths.end()) {
+        frameworkSearchPaths.push_back(linkDir);
+      }
+    } else {
+      if (std::find(linkSearchPaths.begin(), linkSearchPaths.end(), linkDir) ==
+          linkSearchPaths.end()) {
+        linkSearchPaths.push_back(linkDir);
+      }
+    }
+    // Add target dependency
+    if (libItem->Target && !libItem->Target->IsImported()) {
+      for (auto const& configName : this->CurrentConfigurationTypes) {
+        target->AddDependTarget(configName, libItem->Target->GetName());
+      }
+    }
+    // Get the library target
+    auto* libTarget = FindXCodeTarget(libItem->Target);
+    cmXCodeObject* buildFile;
+    if (!libTarget) {
+      if (libItem->IsPath) {
+        // Get or create a direct file ref in the root project
+        auto it = this->ExternalLibRefs.find(libItem->Value.Value);
+        if (it == this->ExternalLibRefs.end()) {
+          buildFile = CreateXCodeBuildFileFromPath(libItem->Value.Value, gt,
+                                                   "", nullptr);
+          if (!buildFile) {
+            // Add this library item back to a regular linker flag list
+            for (const auto& conf : configItemMap) {
+              addToLinkerArguments(conf.first, libItem);
+            }
+            continue;
+          }
+          this->ExternalLibRefs.emplace(libItem->Value.Value, buildFile);
+        } else {
+          buildFile = it->second;
+        }
+      } else {
+        // Add this library item back to a regular linker flag list
+        for (const auto& conf : configItemMap) {
+          addToLinkerArguments(conf.first, libItem);
+        }
+        continue;
+      }
+    } else {
+      // Add the target output file as a build reference for other targets
+      // to link against
+      auto* fileRefObject = libTarget->GetAttribute("productReference");
+      if (!fileRefObject) {
+        // Add this library item back to a regular linker flag list
+        for (const auto& conf : configItemMap) {
+          addToLinkerArguments(conf.first, libItem);
+        }
+        continue;
+      }
+      auto it = FileRefToBuildFileMap.find(fileRefObject);
+      if (it == FileRefToBuildFileMap.end()) {
+        buildFile = this->CreateObject(cmXCodeObject::PBXBuildFile);
+        buildFile->AddAttribute("fileRef", fileRefObject);
+        FileRefToBuildFileMap[fileRefObject] = buildFile;
+      } else {
+        buildFile = it->second;
+      }
+    }
+    // Add this reference to current target
+    auto* buildPhases = target->GetAttribute("buildPhases");
+    if (!buildPhases) {
+      cmSystemTools::Error("Missing buildPhase of target");
+      continue;
+    }
+    auto* frameworkBuildPhase =
+      buildPhases->GetObject(cmXCodeObject::PBXFrameworksBuildPhase);
+    if (!frameworkBuildPhase) {
+      cmSystemTools::Error("Missing PBXFrameworksBuildPhase of buildPhase");
+      continue;
+    }
+    auto* buildFiles = frameworkBuildPhase->GetAttribute("files");
+    if (!buildFiles) {
+      cmSystemTools::Error("Missing files of PBXFrameworksBuildPhase");
+      continue;
+    }
+    if (buildFile && !buildFiles->HasObject(buildFile)) {
+      buildFiles->AddObject(buildFile);
+    }
+  }
+
   // Loop over configuration types and set per-configuration info.
   for (auto const& configName : this->CurrentConfigurationTypes) {
     {
       // Add object library contents as link flags.
-      std::string linkObjs;
-      const char* sep = "";
+      BuildObjectListOrString libSearchPaths(this, true);
       std::vector<cmSourceFile const*> objs;
       gt->GetExternalObjects(objs, configName);
       for (auto sourceFile : objs) {
         if (sourceFile->GetObjectLibrary().empty()) {
           continue;
         }
-        linkObjs += sep;
-        sep = " ";
-        linkObjs += this->XCodeEscapePath(sourceFile->GetFullPath());
+        libSearchPaths.Add(this->XCodeEscapePath(sourceFile->GetFullPath()));
       }
       this->AppendBuildSettingAttribute(
-        target, this->GetTargetLinkFlagsVar(gt), linkObjs.c_str(), configName);
+        target, this->GetTargetLinkFlagsVar(gt), libSearchPaths.CreateList(),
+        configName);
     }
 
     // Skip link information for object libraries.
@@ -2795,55 +3186,82 @@ void cmGlobalXCodeGenerator::AddDependAndLinkInformation(cmXCodeObject* target)
     }
 
     // Compute the link library and directory information.
-    cmComputeLinkInformation* pcli = gt->GetLinkInformation(configName);
-    if (!pcli) {
+    cmComputeLinkInformation* cli = gt->GetLinkInformation(configName);
+    if (!cli) {
       continue;
     }
-    cmComputeLinkInformation& cli = *pcli;
 
     // Add dependencies directly on library files.
-    for (auto const& libDep : cli.GetDepends()) {
+    for (auto const& libDep : cli->GetDepends()) {
       target->AddDependLibrary(configName, libDep);
     }
 
     // add the library search paths
     {
+      BuildObjectListOrString libSearchPaths(this, true);
       std::string linkDirs;
-      for (auto const& libDir : cli.GetDirectories()) {
+      for (auto const& libDir : cli->GetDirectories()) {
         if (!libDir.empty() && libDir != "/usr/lib") {
-          // Now add the same one but append
-          // $(CONFIGURATION)$(EFFECTIVE_PLATFORM_NAME) to it:
-          linkDirs += " ";
-          linkDirs += this->XCodeEscapePath(
-            libDir + "/$(CONFIGURATION)$(EFFECTIVE_PLATFORM_NAME)");
-          linkDirs += " ";
-          linkDirs += this->XCodeEscapePath(libDir);
+          libSearchPaths.Add(this->XCodeEscapePath(
+            libDir + "/$(CONFIGURATION)$(EFFECTIVE_PLATFORM_NAME)"));
+          libSearchPaths.Add(this->XCodeEscapePath(libDir));
         }
       }
+      // Add previously collected paths where to look for libraries
+      // that were added to "Link Binary With Libraries"
+      for (auto& libDir : linkSearchPaths) {
+        libSearchPaths.Add(this->XCodeEscapePath(libDir));
+      }
       this->AppendBuildSettingAttribute(target, "LIBRARY_SEARCH_PATHS",
-                                        linkDirs.c_str(), configName);
+                                        libSearchPaths.CreateList(),
+                                        configName);
+    }
+
+    // add framework search paths
+    {
+      BuildObjectListOrString fwSearchPaths(this, true);
+      // Add previously collected paths where to look for frameworks
+      // that were added to "Link Binary With Libraries"
+      for (auto& fwDir : frameworkSearchPaths) {
+        fwSearchPaths.Add(this->XCodeEscapePath(fwDir));
+      }
+      this->AppendBuildSettingAttribute(target, "FRAMEWORK_SEARCH_PATHS",
+                                        fwSearchPaths.CreateList(),
+                                        configName);
     }
 
-    // now add the link libraries
+    // now add the left-over link libraries
     {
-      std::string linkLibs;
-      const char* sep = "";
-      for (auto const& libName : cli.GetItems()) {
-        linkLibs += sep;
-        sep = " ";
+      BuildObjectListOrString libPaths(this, true);
+      for (auto const& libItem : configItemMap[configName]) {
+        auto const& libName = *libItem;
         if (libName.IsPath) {
-          linkLibs += this->XCodeEscapePath(libName.Value.Value);
+          libPaths.Add(this->XCodeEscapePath(libName.Value.Value));
+          const auto libPath = GetLibraryOrFrameworkPath(libName.Value.Value);
+          if ((!libName.Target || libName.Target->IsImported()) &&
+              IsLinkPhaseLibraryExtension(libPath)) {
+            // Create file reference for embedding
+            auto it = this->ExternalLibRefs.find(libName.Value.Value);
+            if (it == this->ExternalLibRefs.end()) {
+              auto* buildFile = this->CreateXCodeBuildFileFromPath(
+                libName.Value.Value, gt, "", nullptr);
+              if (buildFile) {
+                this->ExternalLibRefs.emplace(libName.Value.Value, buildFile);
+              }
+            }
+          }
         } else if (!libName.Target ||
                    libName.Target->GetType() !=
                      cmStateEnums::INTERFACE_LIBRARY) {
-          linkLibs += libName.Value.Value;
+          libPaths.Add(libName.Value.Value);
         }
         if (libName.Target && !libName.Target->IsImported()) {
           target->AddDependTarget(configName, libName.Target->GetName());
         }
       }
-      this->AppendBuildSettingAttribute(
-        target, this->GetTargetLinkFlagsVar(gt), linkLibs.c_str(), configName);
+      this->AppendBuildSettingAttribute(target,
+                                        this->GetTargetLinkFlagsVar(gt),
+                                        libPaths.CreateList(), configName);
     }
   }
 }
@@ -2859,13 +3277,9 @@ bool cmGlobalXCodeGenerator::CreateGroups(
       // end up with (empty anyhow) ZERO_CHECK, install, or test source
       // groups:
       //
-      if (gtgt->GetType() == cmStateEnums::GLOBAL_TARGET) {
-        continue;
-      }
-      if (gtgt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
-        continue;
-      }
-      if (gtgt->GetName() == CMAKE_CHECK_BUILD_SYSTEM_TARGET) {
+      if (!gtgt->IsInBuildSystem() ||
+          gtgt->GetType() == cmStateEnums::GLOBAL_TARGET ||
+          gtgt->GetName() == CMAKE_CHECK_BUILD_SYSTEM_TARGET) {
         continue;
       }
 
@@ -2915,7 +3329,7 @@ cmXCodeObject* cmGlobalXCodeGenerator::CreatePBXGroup(cmXCodeObject* parent,
 {
   cmXCodeObject* parentChildren = nullptr;
   if (parent) {
-    parentChildren = parent->GetObject("children");
+    parentChildren = parent->GetAttribute("children");
   }
   cmXCodeObject* group = this->CreateObject(cmXCodeObject::PBXGroup);
   cmXCodeObject* groupChildren =
@@ -3009,6 +3423,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
   this->ClearXCodeObjects();
   this->RootObject = nullptr;
   this->MainGroupChildren = nullptr;
+  this->FrameworkGroup = nullptr;
   cmXCodeObject* group = this->CreateObject(cmXCodeObject::ATTRIBUTE_GROUP);
   group->AddAttribute("COPY_PHASE_STRIP", this->CreateString("NO"));
   cmXCodeObject* listObjs = this->CreateObject(cmXCodeObject::OBJECT_LIST);
@@ -3043,6 +3458,15 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
   productGroup->AddAttribute("children", productGroupChildren);
   this->MainGroupChildren->AddObject(productGroup);
 
+  this->FrameworkGroup = this->CreateObject(cmXCodeObject::PBXGroup);
+  this->FrameworkGroup->AddAttribute("name", this->CreateString("Frameworks"));
+  this->FrameworkGroup->AddAttribute("sourceTree",
+                                     this->CreateString("<group>"));
+  cmXCodeObject* frameworkGroupChildren =
+    this->CreateObject(cmXCodeObject::OBJECT_LIST);
+  this->FrameworkGroup->AddAttribute("children", frameworkGroupChildren);
+  this->MainGroupChildren->AddObject(this->FrameworkGroup);
+
   this->RootObject = this->CreateObject(cmXCodeObject::PBXProject);
   this->RootObject->SetComment("Project object");
 
@@ -3106,12 +3530,11 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
                            this->CreateString(defaultConfigName));
   cmXCodeObject* buildSettings =
     this->CreateObject(cmXCodeObject::ATTRIBUTE_GROUP);
-  const char* sysroot =
-    this->CurrentMakefile->GetDefinition("CMAKE_OSX_SYSROOT");
-  const char* deploymentTarget =
+  cmProp sysroot = this->CurrentMakefile->GetDefinition("CMAKE_OSX_SYSROOT");
+  cmProp deploymentTarget =
     this->CurrentMakefile->GetDefinition("CMAKE_OSX_DEPLOYMENT_TARGET");
   if (sysroot) {
-    buildSettings->AddAttribute("SDKROOT", this->CreateString(sysroot));
+    buildSettings->AddAttribute("SDKROOT", this->CreateString(*sysroot));
   }
   // recompute this as it may have been changed since enable language
   this->ComputeArchitectures(this->CurrentMakefile);
@@ -3121,8 +3544,8 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
     buildSettings->AddAttribute("ONLY_ACTIVE_ARCH", this->CreateString("YES"));
     // When targeting macOS, use only the host architecture.
     if (this->SystemName == "Darwin"_s &&
-        (!sysroot || !*sysroot ||
-         cmSystemTools::LowerCase(sysroot).find("macos") !=
+        (!cmNonempty(sysroot) ||
+         cmSystemTools::LowerCase(*sysroot).find("macos") !=
            std::string::npos)) {
       buildSettings->AddAttribute("ARCHS",
                                   this->CreateString("$(NATIVE_ARCH_ACTUAL)"));
@@ -3131,9 +3554,9 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
     // Tell Xcode to use ARCHS (ONLY_ACTIVE_ARCH defaults to NO).
     buildSettings->AddAttribute("ARCHS", this->CreateString(archs));
   }
-  if (deploymentTarget && *deploymentTarget) {
+  if (cmNonempty(deploymentTarget)) {
     buildSettings->AddAttribute(GetDeploymentPlatform(root->GetMakefile()),
-                                this->CreateString(deploymentTarget));
+                                this->CreateString(*deploymentTarget));
   }
   if (!this->GeneratorToolset.empty()) {
     buildSettings->AddAttribute("GCC_VERSION",
@@ -3141,9 +3564,9 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
   }
   if (this->GetLanguageEnabled("Swift")) {
     std::string swiftVersion;
-    if (const char* vers = this->CurrentMakefile->GetDefinition(
+    if (cmProp vers = this->CurrentMakefile->GetDefinition(
           "CMAKE_Swift_LANGUAGE_VERSION")) {
-      swiftVersion = vers;
+      swiftVersion = *vers;
     } else if (this->XcodeVersion >= 102) {
       swiftVersion = "4.0";
     } else if (this->XcodeVersion >= 83) {
@@ -3204,7 +3627,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
   cmXCodeObject* allTargets = this->CreateObject(cmXCodeObject::OBJECT_LIST);
   for (auto t : targets) {
     allTargets->AddObject(t);
-    cmXCodeObject* productRef = t->GetObject("productReference");
+    cmXCodeObject* productRef = t->GetAttribute("productReference");
     if (productRef) {
       productGroupChildren->AddObject(productRef->GetObject());
     }
@@ -3226,7 +3649,7 @@ std::string cmGlobalXCodeGenerator::GetObjectsDirectory(
 void cmGlobalXCodeGenerator::ComputeArchitectures(cmMakefile* mf)
 {
   this->Architectures.clear();
-  const char* sysroot = mf->GetDefinition("CMAKE_OSX_SYSROOT");
+  cmProp sysroot = mf->GetDefinition("CMAKE_OSX_SYSROOT");
   if (sysroot) {
     mf->GetDefExpandList("CMAKE_OSX_ARCHITECTURES", this->Architectures);
   }
@@ -3235,8 +3658,8 @@ void cmGlobalXCodeGenerator::ComputeArchitectures(cmMakefile* mf)
     // With no ARCHS we use ONLY_ACTIVE_ARCH and possibly a
     // platform-specific default ARCHS placeholder value.
     // Look up the arch that Xcode chooses in this case.
-    if (const char* arch = mf->GetDefinition("CMAKE_XCODE_ARCHS")) {
-      this->ObjectDirArchDefault = arch;
+    if (cmProp arch = mf->GetDefinition("CMAKE_XCODE_ARCHS")) {
+      this->ObjectDirArchDefault = *arch;
       // We expect only one arch but choose the first just in case.
       std::string::size_type pos = this->ObjectDirArchDefault.find(';');
       if (pos != std::string::npos) {
@@ -3602,9 +4025,9 @@ std::string cmGlobalXCodeGenerator::LookupFlags(
 {
   if (!varNameLang.empty()) {
     std::string varName = cmStrCat(varNamePrefix, varNameLang, varNameSuffix);
-    if (const char* varValue = this->CurrentMakefile->GetDefinition(varName)) {
-      if (*varValue) {
-        return varValue;
+    if (cmProp varValue = this->CurrentMakefile->GetDefinition(varName)) {
+      if (!varValue->empty()) {
+        return *varValue;
       }
     }
   }
diff --git a/Source/cmGlobalXCodeGenerator.h b/Source/cmGlobalXCodeGenerator.h
index e2d1b3a..c7524e8 100644
--- a/Source/cmGlobalXCodeGenerator.h
+++ b/Source/cmGlobalXCodeGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGlobalXCodeGenerator_h
-#define cmGlobalXCodeGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -28,7 +27,7 @@ struct cmDocumentationEntry;
 /** \class cmGlobalXCodeGenerator
  * \brief Write a Unix makefiles.
  *
- * cmGlobalXCodeGenerator manages UNIX build process for a tree
+ * cmGlobalXCodeGenerator manages Xcode build process for a tree
  */
 class cmGlobalXCodeGenerator : public cmGlobalGenerator
 {
@@ -116,8 +115,6 @@ public:
 
 protected:
   void AddExtraIDETargets() override;
-  void ComputeTargetOrder();
-  void ComputeTargetOrder(cmGeneratorTarget const* gt, size_t& index);
   void Generate() override;
 
 private:
@@ -168,9 +165,9 @@ private:
   std::string AddConfigurations(cmXCodeObject* target,
                                 cmGeneratorTarget* gtgt);
   void AppendOrAddBuildSetting(cmXCodeObject* settings, const char* attr,
-                               const char* value);
+                               cmXCodeObject* value);
   void AppendBuildSettingAttribute(cmXCodeObject* target, const char* attr,
-                                   const char* value,
+                                   cmXCodeObject* value,
                                    const std::string& configName);
   cmXCodeObject* CreateUtilityTarget(cmGeneratorTarget* gtgt);
   void AddDependAndLinkInformation(cmXCodeObject* target);
@@ -204,10 +201,10 @@ private:
                                                   cmGeneratorTarget* target,
                                                   const std::string& lang,
                                                   cmSourceFile* sf);
-  cmXCodeObject* CreateXCodeSourceFileFromPath(const std::string& fullpath,
-                                               cmGeneratorTarget* target,
-                                               const std::string& lang,
-                                               cmSourceFile* sf);
+  cmXCodeObject* CreateXCodeBuildFileFromPath(const std::string& fullpath,
+                                              cmGeneratorTarget* target,
+                                              const std::string& lang,
+                                              cmSourceFile* sf);
   cmXCodeObject* CreateXCodeFileReference(cmSourceFile* sf,
                                           cmGeneratorTarget* target);
   cmXCodeObject* CreateXCodeSourceFile(cmLocalGenerator* gen, cmSourceFile* sf,
@@ -282,6 +279,7 @@ private:
   std::string PostBuildMakeTarget(std::string const& tName,
                                   std::string const& configName);
   cmXCodeObject* MainGroupChildren;
+  cmXCodeObject* FrameworkGroup;
   cmMakefile* CurrentMakefile;
   cmLocalGenerator* CurrentLocalGenerator;
   std::vector<std::string> CurrentConfigurationTypes;
@@ -295,13 +293,15 @@ private:
   std::map<std::string, cmXCodeObject*> GroupNameMap;
   std::map<std::string, cmXCodeObject*> TargetGroup;
   std::map<std::string, cmXCodeObject*> FileRefs;
+  std::map<std::string, cmXCodeObject*> ExternalLibRefs;
   std::map<cmGeneratorTarget const*, cmXCodeObject*> XCodeObjectMap;
+  std::map<cmXCodeObject*, cmXCodeObject*> FileRefToBuildFileMap;
   std::vector<std::string> Architectures;
   std::string ObjectDirArchDefault;
   std::string ObjectDirArch;
   std::string SystemName;
   std::string GeneratorToolset;
-  std::map<cmGeneratorTarget const*, size_t> TargetOrderIndex;
+  std::vector<std::string> EnabledLangs;
+  std::map<cmGeneratorTarget const*, std::set<cmSourceFile const*>>
+    CommandsVisited;
 };
-
-#endif
diff --git a/Source/cmGraphAdjacencyList.h b/Source/cmGraphAdjacencyList.h
index 4e1f128..fe9fbe2 100644
--- a/Source/cmGraphAdjacencyList.h
+++ b/Source/cmGraphAdjacencyList.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmGraphAdjacencyList_h
-#define cmGraphAdjacencyList_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -48,5 +47,3 @@ struct cmGraphNodeList : public std::vector<int>
 struct cmGraphAdjacencyList : public std::vector<cmGraphEdgeList>
 {
 };
-
-#endif
diff --git a/Source/cmGraphVizWriter.cxx b/Source/cmGraphVizWriter.cxx
index c23156d..cf4ba93 100644
--- a/Source/cmGraphVizWriter.cxx
+++ b/Source/cmGraphVizWriter.cxx
@@ -2,6 +2,7 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmGraphVizWriter.h"
 
+#include <algorithm>
 #include <cctype>
 #include <iostream>
 #include <memory>
@@ -16,6 +17,7 @@
 #include "cmLinkItem.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
+#include "cmProperty.h"
 #include "cmState.h"
 #include "cmStateSnapshot.h"
 #include "cmStringAlgorithms.h"
@@ -125,14 +127,6 @@ cmGraphVizWriter::cmGraphVizWriter(std::string const& fileName,
 cmGraphVizWriter::~cmGraphVizWriter()
 {
   this->WriteFooter(this->GlobalFileStream);
-
-  for (auto& fileStream : this->PerTargetFileStreams) {
-    this->WriteFooter(*fileStream.second);
-  }
-
-  for (auto& fileStream : this->TargetDependersFileStreams) {
-    this->WriteFooter(*fileStream.second);
-  }
 }
 
 void cmGraphVizWriter::VisitGraph(std::string const&)
@@ -151,20 +145,10 @@ void cmGraphVizWriter::OnItem(cmLinkItem const& item)
   ++NextNodeId;
 
   this->WriteNode(this->GlobalFileStream, item);
-
-  if (this->GeneratePerTarget) {
-    this->CreateTargetFile(this->PerTargetFileStreams, item);
-  }
-
-  if (this->GenerateDependers) {
-    this->CreateTargetFile(this->TargetDependersFileStreams, item,
-                           ".dependers");
-  }
 }
 
-void cmGraphVizWriter::CreateTargetFile(FileStreamMap& fileStreamMap,
-                                        cmLinkItem const& item,
-                                        std::string const& fileNameSuffix)
+std::unique_ptr<cmGeneratedFileStream> cmGraphVizWriter::CreateTargetFile(
+  cmLinkItem const& item, std::string const& fileNameSuffix)
 {
   auto const pathSafeItemName = PathSafeString(item.AsStr());
   auto const perTargetFileName =
@@ -175,7 +159,7 @@ void cmGraphVizWriter::CreateTargetFile(FileStreamMap& fileStreamMap,
   this->WriteHeader(*perTargetFileStream, item.AsStr());
   this->WriteNode(*perTargetFileStream, item);
 
-  fileStreamMap.emplace(item.AsStr(), std::move(perTargetFileStream));
+  return perTargetFileStream;
 }
 
 void cmGraphVizWriter::OnDirectLink(cmLinkItem const& depender,
@@ -246,9 +230,9 @@ void cmGraphVizWriter::ReadSettings(
 
 #define __set_if_set(var, cmakeDefinition)                                    \
   do {                                                                        \
-    const char* value = mf.GetDefinition(cmakeDefinition);                    \
+    cmProp value = mf.GetDefinition(cmakeDefinition);                         \
     if (value) {                                                              \
-      (var) = value;                                                          \
+      (var) = *value;                                                         \
     }                                                                         \
   } while (false)
 
@@ -258,9 +242,9 @@ void cmGraphVizWriter::ReadSettings(
 
 #define __set_bool_if_set(var, cmakeDefinition)                               \
   do {                                                                        \
-    const char* value = mf.GetDefinition(cmakeDefinition);                    \
+    cmProp value = mf.GetDefinition(cmakeDefinition);                         \
     if (value) {                                                              \
-      (var) = mf.IsOn(cmakeDefinition);                                       \
+      (var) = cmIsOn(*value);                                                 \
     }                                                                         \
   } while (false)
 
@@ -323,13 +307,12 @@ void cmGraphVizWriter::Write()
   }
 
   if (this->GeneratePerTarget) {
-    WritePerTargetConnections<DependeesDir>(PerTargetConnections,
-                                            PerTargetFileStreams);
+    WritePerTargetConnections<DependeesDir>(PerTargetConnections);
   }
 
   if (this->GenerateDependers) {
     WritePerTargetConnections<DependersDir>(TargetDependersConnections,
-                                            TargetDependersFileStreams);
+                                            ".dependers");
   }
 }
 
@@ -368,7 +351,7 @@ void cmGraphVizWriter::FindAllConnections(const ConnectionsMap& connectionMap,
 
 template <typename DirFunc>
 void cmGraphVizWriter::WritePerTargetConnections(
-  const ConnectionsMap& connections, const FileStreamMap& streams)
+  const ConnectionsMap& connections, const std::string& fileNameSuffix)
 {
   // the per target connections must be extended by indirect dependencies
   ConnectionsMap extendedConnections;
@@ -387,7 +370,9 @@ void cmGraphVizWriter::WritePerTargetConnections(
     }
 
     const Connections& cons = conPerTarget.second;
-    auto fileStream = streams.at(rootItem.AsStr()).get();
+
+    std::unique_ptr<cmGeneratedFileStream> fileStream =
+      this->CreateTargetFile(rootItem, fileNameSuffix);
 
     for (const Connection& con : cons) {
       const cmLinkItem& src = DirFunc::src(con);
@@ -395,6 +380,8 @@ void cmGraphVizWriter::WritePerTargetConnections(
       this->WriteNode(*fileStream, con.dst);
       this->WriteConnection(*fileStream, src, dst, con.scopeType);
     }
+
+    this->WriteFooter(*fileStream);
   }
 }
 
@@ -567,16 +554,23 @@ bool cmGraphVizWriter::TargetTypeEnabled(
 std::string cmGraphVizWriter::ItemNameWithAliases(
   std::string const& itemName) const
 {
-  auto nameWithAliases = itemName;
-
+  std::vector<std::string> items;
   for (auto const& lg : this->GlobalGenerator->GetLocalGenerators()) {
     for (auto const& aliasTargets : lg->GetMakefile()->GetAliasTargets()) {
       if (aliasTargets.second == itemName) {
-        nameWithAliases += "\\n(" + aliasTargets.first + ")";
+        items.push_back(aliasTargets.first);
       }
     }
   }
 
+  std::sort(items.begin(), items.end());
+  items.erase(std::unique(items.begin(), items.end()), items.end());
+
+  auto nameWithAliases = itemName;
+  for(auto const& item : items) {
+    nameWithAliases += "\\n(" + item + ")";
+  }
+
   return nameWithAliases;
 }
 
diff --git a/Source/cmGraphVizWriter.h b/Source/cmGraphVizWriter.h
index 9766068..0912fc8 100644
--- a/Source/cmGraphVizWriter.h
+++ b/Source/cmGraphVizWriter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef CMGRAPHVIZWRITER_H
-#define CMGRAPHVIZWRITER_H
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -46,9 +45,6 @@ public:
   void Write();
 
 private:
-  using FileStreamMap =
-    std::map<std::string, std::unique_ptr<cmGeneratedFileStream>>;
-
   struct Connection
   {
     Connection(cmLinkItem s, cmLinkItem d, std::string scope)
@@ -76,8 +72,8 @@ private:
 
   void WriteNode(cmGeneratedFileStream& fs, cmLinkItem const& item);
 
-  void CreateTargetFile(FileStreamMap& fileStreamMap, cmLinkItem const& target,
-                        std::string const& fileNameSuffix = "");
+  std::unique_ptr<cmGeneratedFileStream> CreateTargetFile(
+    cmLinkItem const& target, std::string const& fileNameSuffix = "");
 
   void WriteConnection(cmGeneratedFileStream& fs,
                        cmLinkItem const& dependerTargetName,
@@ -95,7 +91,7 @@ private:
 
   template <typename DirFunc>
   void WritePerTargetConnections(const ConnectionsMap& connections,
-                                 const FileStreamMap& streams);
+                                 const std::string& fileNameSuffix = "");
 
   bool ItemExcluded(cmLinkItem const& item);
   bool ItemNameFilteredOut(std::string const& itemName);
@@ -111,8 +107,6 @@ private:
 
   std::string FileName;
   cmGeneratedFileStream GlobalFileStream;
-  FileStreamMap PerTargetFileStreams;
-  FileStreamMap TargetDependersFileStreams;
 
   ConnectionsMap PerTargetConnections;
   ConnectionsMap TargetDependersConnections;
@@ -141,5 +135,3 @@ private:
   bool GeneratePerTarget;
   bool GenerateDependers;
 };
-
-#endif
diff --git a/Source/cmHexFileConverter.h b/Source/cmHexFileConverter.h
index 26f9ea8..35a91ed 100644
--- a/Source/cmHexFileConverter.h
+++ b/Source/cmHexFileConverter.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmHexFileConverter_h
-#define cmHexFileConverter_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -25,5 +24,3 @@ public:
   static bool TryConvert(const std::string& inFileName,
                          const std::string& outFileName);
 };
-
-#endif
diff --git a/Source/cmIDEFlagTable.h b/Source/cmIDEFlagTable.h
index ff93432..5901771 100644
--- a/Source/cmIDEFlagTable.h
+++ b/Source/cmIDEFlagTable.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIDEFlagTable_h
-#define cmIDEFlagTable_h
+#pragma once
 
 #include <string>
 
@@ -37,5 +36,3 @@ struct cmIDEFlagTable
     UserValueRequired = UserValue | UserRequired
   };
 };
-
-#endif
diff --git a/Source/cmIDEOptions.h b/Source/cmIDEOptions.h
index f949ae3..fbe9c37 100644
--- a/Source/cmIDEOptions.h
+++ b/Source/cmIDEOptions.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIDEOptions_h
-#define cmIDEOptions_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -112,5 +111,3 @@ protected:
                      std::string const& new_value);
   virtual void StoreUnknownFlag(std::string const& flag) = 0;
 };
-
-#endif
diff --git a/Source/cmIfCommand.h b/Source/cmIfCommand.h
index 820ffa4..f056587 100644
--- a/Source/cmIfCommand.h
+++ b/Source/cmIfCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIfCommand_h
-#define cmIfCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -13,5 +12,3 @@ struct cmListFileArgument;
 /// Starts an if block
 bool cmIfCommand(std::vector<cmListFileArgument> const& args,
                  cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmIncludeCommand.h b/Source/cmIncludeCommand.h
index b0dd779..af26163 100644
--- a/Source/cmIncludeCommand.h
+++ b/Source/cmIncludeCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIncludeCommand_h
-#define cmIncludeCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -18,5 +17,3 @@ class cmExecutionStatus;
  */
 bool cmIncludeCommand(std::vector<std::string> const& args,
                       cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmIncludeDirectoryCommand.h b/Source/cmIncludeDirectoryCommand.h
index 66caff7..d830dbf 100644
--- a/Source/cmIncludeDirectoryCommand.h
+++ b/Source/cmIncludeDirectoryCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIncludeDirectoryCommand_h
-#define cmIncludeDirectoryCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmIncludeDirectoryCommand(std::vector<std::string> const& args,
                                cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmIncludeExternalMSProjectCommand.h b/Source/cmIncludeExternalMSProjectCommand.h
index 1013c44..fd77407 100644
--- a/Source/cmIncludeExternalMSProjectCommand.h
+++ b/Source/cmIncludeExternalMSProjectCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIncludeExternalMSProjectCommand_h
-#define cmIncludeExternalMSProjectCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmIncludeExternalMSProjectCommand(std::vector<std::string> const& args,
                                        cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmIncludeGuardCommand.cxx b/Source/cmIncludeGuardCommand.cxx
index ccb4496..aefd098 100644
--- a/Source/cmIncludeGuardCommand.cxx
+++ b/Source/cmIncludeGuardCommand.cxx
@@ -75,7 +75,7 @@ bool cmIncludeGuardCommand(std::vector<std::string> const& args,
   }
 
   std::string includeGuardVar = GetIncludeGuardVariableName(
-    status.GetMakefile().GetDefinition("CMAKE_CURRENT_LIST_FILE"));
+    *status.GetMakefile().GetDefinition("CMAKE_CURRENT_LIST_FILE"));
 
   cmMakefile* const mf = &status.GetMakefile();
 
diff --git a/Source/cmIncludeGuardCommand.h b/Source/cmIncludeGuardCommand.h
index b86b760..c4de3d4 100644
--- a/Source/cmIncludeGuardCommand.h
+++ b/Source/cmIncludeGuardCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIncludeGuardCommand_h
-#define cmIncludeGuardCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -18,5 +17,3 @@ class cmExecutionStatus;
  */
 bool cmIncludeGuardCommand(std::vector<std::string> const& args,
                            cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmIncludeRegularExpressionCommand.h b/Source/cmIncludeRegularExpressionCommand.h
index ca152b0..a402f97 100644
--- a/Source/cmIncludeRegularExpressionCommand.h
+++ b/Source/cmIncludeRegularExpressionCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmIncludeRegularExpressionCommand_h
-#define cmIncludeRegularExpressionCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmIncludeRegularExpressionCommand(std::vector<std::string> const& args,
                                        cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmInstallCommand.cxx b/Source/cmInstallCommand.cxx
index 178af73..83609e2 100644
--- a/Source/cmInstallCommand.cxx
+++ b/Source/cmInstallCommand.cxx
@@ -680,7 +680,7 @@ bool HandleTargetsMode(std::vector<std::string> const& args,
 
     if (createInstallGeneratorsForTargetFileSets && !namelinkOnly) {
       cmProp files = target.GetProperty("PRIVATE_HEADER");
-      if (files && !files->empty()) {
+      if (cmNonempty(files)) {
         std::vector<std::string> relFiles = cmExpandedList(*files);
         std::vector<std::string> absFiles;
         if (!helper.MakeFilesFullPath("PRIVATE_HEADER", relFiles, absFiles)) {
@@ -702,7 +702,7 @@ bool HandleTargetsMode(std::vector<std::string> const& args,
       }
 
       files = target.GetProperty("PUBLIC_HEADER");
-      if (files && !files->empty()) {
+      if (cmNonempty(files)) {
         std::vector<std::string> relFiles = cmExpandedList(*files);
         std::vector<std::string> absFiles;
         if (!helper.MakeFilesFullPath("PUBLIC_HEADER", relFiles, absFiles)) {
@@ -724,7 +724,7 @@ bool HandleTargetsMode(std::vector<std::string> const& args,
       }
 
       files = target.GetProperty("RESOURCE");
-      if (files && !files->empty()) {
+      if (cmNonempty(files)) {
         std::vector<std::string> relFiles = cmExpandedList(*files);
         std::vector<std::string> absFiles;
         if (!helper.MakeFilesFullPath("RESOURCE", relFiles, absFiles)) {
@@ -1157,7 +1157,7 @@ bool HandleDirectoryMode(std::vector<std::string> const& args,
     } else if (doing == DoingRegex) {
       literal_args += " REGEX \"";
 // Match rules are case-insensitive on some platforms.
-#if defined(_WIN32) || defined(__APPLE__) || defined(__CYGWIN__)
+#if defined(_WIN32) || defined(__APPLE__)
       std::string regex = cmSystemTools::LowerCase(args[i]);
 #else
       std::string regex = args[i];
diff --git a/Source/cmInstallCommand.h b/Source/cmInstallCommand.h
index 32f00ce..f0ba44e 100644
--- a/Source/cmInstallCommand.h
+++ b/Source/cmInstallCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallCommand_h
-#define cmInstallCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmInstallCommand(std::vector<std::string> const& args,
                       cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmInstallCommandArguments.h b/Source/cmInstallCommandArguments.h
index 5d2ee0a..f318a1a 100644
--- a/Source/cmInstallCommandArguments.h
+++ b/Source/cmInstallCommandArguments.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallCommandArguments_h
-#define cmInstallCommandArguments_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -72,5 +71,3 @@ public:
 private:
   std::vector<std::string> IncludeDirs;
 };
-
-#endif
diff --git a/Source/cmInstallDirectoryGenerator.h b/Source/cmInstallDirectoryGenerator.h
index bec89df..af310f3 100644
--- a/Source/cmInstallDirectoryGenerator.h
+++ b/Source/cmInstallDirectoryGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallDirectoryGenerator_h
-#define cmInstallDirectoryGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -48,5 +47,3 @@ protected:
   std::string const LiteralArguments;
   bool const Optional;
 };
-
-#endif
diff --git a/Source/cmInstallExportGenerator.h b/Source/cmInstallExportGenerator.h
index 43dd00d..dd8624b 100644
--- a/Source/cmInstallExportGenerator.h
+++ b/Source/cmInstallExportGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallExportGenerator_h
-#define cmInstallExportGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -68,5 +67,3 @@ protected:
   std::string MainImportFile;
   std::unique_ptr<cmExportInstallFileGenerator> EFGen;
 };
-
-#endif
diff --git a/Source/cmInstallFilesCommand.h b/Source/cmInstallFilesCommand.h
index f4ebbde..219bb97 100644
--- a/Source/cmInstallFilesCommand.h
+++ b/Source/cmInstallFilesCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallFilesCommand_h
-#define cmInstallFilesCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmInstallFilesCommand(std::vector<std::string> const& args,
                            cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmInstallFilesGenerator.h b/Source/cmInstallFilesGenerator.h
index 8266603..b5a1ef4 100644
--- a/Source/cmInstallFilesGenerator.h
+++ b/Source/cmInstallFilesGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallFilesGenerator_h
-#define cmInstallFilesGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -48,5 +47,3 @@ protected:
   bool const Programs;
   bool const Optional;
 };
-
-#endif
diff --git a/Source/cmInstallGenerator.h b/Source/cmInstallGenerator.h
index d786d24..ee55ee9 100644
--- a/Source/cmInstallGenerator.h
+++ b/Source/cmInstallGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallGenerator_h
-#define cmInstallGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -74,5 +73,3 @@ protected:
   MessageLevel const Message;
   bool const ExcludeFromAll;
 };
-
-#endif
diff --git a/Source/cmInstallProgramsCommand.h b/Source/cmInstallProgramsCommand.h
index c567f3b..e3c3e81 100644
--- a/Source/cmInstallProgramsCommand.h
+++ b/Source/cmInstallProgramsCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallProgramsCommand_h
-#define cmInstallProgramsCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmInstallProgramsCommand(std::vector<std::string> const& args,
                               cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmInstallScriptGenerator.h b/Source/cmInstallScriptGenerator.h
index 0a9c4ba..338d866 100644
--- a/Source/cmInstallScriptGenerator.h
+++ b/Source/cmInstallScriptGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallScriptGenerator_h
-#define cmInstallScriptGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -38,5 +37,3 @@ protected:
   cmLocalGenerator* LocalGenerator;
   bool AllowGenex;
 };
-
-#endif
diff --git a/Source/cmInstallSubdirectoryGenerator.h b/Source/cmInstallSubdirectoryGenerator.h
index f9cd0f1..3e46d6b 100644
--- a/Source/cmInstallSubdirectoryGenerator.h
+++ b/Source/cmInstallSubdirectoryGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallSubdirectoryGenerator_h
-#define cmInstallSubdirectoryGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -37,5 +36,3 @@ protected:
   std::string const BinaryDirectory;
   cmLocalGenerator* LocalGenerator;
 };
-
-#endif
diff --git a/Source/cmInstallTargetGenerator.cxx b/Source/cmInstallTargetGenerator.cxx
index 178d5df..b3da202 100644
--- a/Source/cmInstallTargetGenerator.cxx
+++ b/Source/cmInstallTargetGenerator.cxx
@@ -820,7 +820,7 @@ void cmInstallTargetGenerator::AddStripRule(std::ostream& os, Indent indent,
 
   os << indent << "if(CMAKE_INSTALL_DO_STRIP)\n";
   os << indent << "  execute_process(COMMAND \""
-     << this->Target->Target->GetMakefile()->GetDefinition("CMAKE_STRIP")
+     << this->Target->Target->GetMakefile()->GetSafeDefinition("CMAKE_STRIP")
      << "\" " << stripArgs << "\"" << toDestDirPath << "\")\n";
   os << indent << "endif()\n";
 }
@@ -858,9 +858,9 @@ void cmInstallTargetGenerator::AddUniversalInstallRule(
     return;
   }
 
-  const char* xcodeVersion = mf->GetDefinition("XCODE_VERSION");
+  cmProp xcodeVersion = mf->GetDefinition("XCODE_VERSION");
   if (!xcodeVersion ||
-      cmSystemTools::VersionCompareGreater("6", xcodeVersion)) {
+      cmSystemTools::VersionCompareGreater("6", *xcodeVersion)) {
     return;
   }
 
diff --git a/Source/cmInstallTargetGenerator.h b/Source/cmInstallTargetGenerator.h
index e21001f..a53a75a 100644
--- a/Source/cmInstallTargetGenerator.h
+++ b/Source/cmInstallTargetGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallTargetGenerator_h
-#define cmInstallTargetGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -114,5 +113,3 @@ protected:
   bool const Optional;
   cmListFileBacktrace const Backtrace;
 };
-
-#endif
diff --git a/Source/cmInstallTargetsCommand.h b/Source/cmInstallTargetsCommand.h
index 0c5850c..716e7ce 100644
--- a/Source/cmInstallTargetsCommand.h
+++ b/Source/cmInstallTargetsCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallTargetsCommand_h
-#define cmInstallTargetsCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmInstallTargetsCommand(std::vector<std::string> const& args,
                              cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmInstallType.h b/Source/cmInstallType.h
index e2602cb..33fa7a9 100644
--- a/Source/cmInstallType.h
+++ b/Source/cmInstallType.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstallType_h
-#define cmInstallType_h
+#pragma once
 
 /**
  * Enumerate types known to file(INSTALL).
@@ -16,5 +15,3 @@ enum cmInstallType
   cmInstallType_PROGRAMS,
   cmInstallType_DIRECTORY
 };
-
-#endif
diff --git a/Source/cmInstalledFile.h b/Source/cmInstalledFile.h
index 07f7081..82474f5 100644
--- a/Source/cmInstalledFile.h
+++ b/Source/cmInstalledFile.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmInstalledFile_h
-#define cmInstalledFile_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -76,5 +75,3 @@ private:
   CompiledGeneratorExpressionPtrType NameExpression;
   PropertyMapType Properties;
 };
-
-#endif
diff --git a/Source/cmJsonObjects.cxx b/Source/cmJsonObjects.cxx
index 9f17f15..3a7ae0c 100644
--- a/Source/cmJsonObjects.cxx
+++ b/Source/cmJsonObjects.cxx
@@ -51,11 +51,7 @@ std::vector<std::string> getConfigurations(const cmake* cm)
     return configurations;
   }
 
-  makefiles[0]->GetConfigurations(configurations);
-  if (configurations.empty()) {
-    configurations.emplace_back();
-  }
-  return configurations;
+  return makefiles[0]->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 }
 
 bool hasString(const Json::Value& v, const std::string& s)
@@ -635,8 +631,8 @@ static Json::Value DumpProjectList(const cmake* cm, std::string const& config)
 
     // Project structure information:
     const cmMakefile* mf = lg->GetMakefile();
-    auto minVersion = mf->GetDefinition("CMAKE_MINIMUM_REQUIRED_VERSION");
-    pObj[kMINIMUM_CMAKE_VERSION] = minVersion ? minVersion : "";
+    auto minVersion = mf->GetSafeDefinition("CMAKE_MINIMUM_REQUIRED_VERSION");
+    pObj[kMINIMUM_CMAKE_VERSION] = minVersion;
     pObj[kSOURCE_DIRECTORY_KEY] = mf->GetCurrentSourceDirectory();
     pObj[kBUILD_DIRECTORY_KEY] = mf->GetCurrentBinaryDirectory();
     pObj[kTARGETS_KEY] = DumpTargetsList(projectIt.second, config);
diff --git a/Source/cmJsonObjects.h b/Source/cmJsonObjects.h
index 2fd4b26..80a4834 100644
--- a/Source/cmJsonObjects.h
+++ b/Source/cmJsonObjects.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmJsonObjects_h
-#define cmJsonObjects_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -23,5 +22,3 @@ extern void cmGetCMakeInputs(const cmGlobalGenerator* gg,
 extern Json::Value cmDumpCodeModel(const cmake* cm);
 extern Json::Value cmDumpCTestInfo(const cmake* cm);
 extern Json::Value cmDumpCMakeInputs(const cmake* cm);
-
-#endif
diff --git a/Source/cmLDConfigLDConfigTool.h b/Source/cmLDConfigLDConfigTool.h
index 34bf6c6..eeb86dd 100644
--- a/Source/cmLDConfigLDConfigTool.h
+++ b/Source/cmLDConfigLDConfigTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmLDConfigLDConfigTool_h
-#define cmLDConfigLDConfigTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -18,5 +17,3 @@ public:
 
   bool GetLDConfigPaths(std::vector<std::string>& paths) override;
 };
-
-#endif
diff --git a/Source/cmLDConfigTool.h b/Source/cmLDConfigTool.h
index c816562..3116f80 100644
--- a/Source/cmLDConfigTool.h
+++ b/Source/cmLDConfigTool.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmLDConfigTool_h
-#define cmLDConfigTool_h
+#pragma once
 
 #include <string>
 #include <vector>
@@ -20,5 +19,3 @@ public:
 protected:
   cmRuntimeDependencyArchive* Archive;
 };
-
-#endif
diff --git a/Source/cmLinkDirectoriesCommand.h b/Source/cmLinkDirectoriesCommand.h
index a7caa5c..2a3499d 100644
--- a/Source/cmLinkDirectoriesCommand.h
+++ b/Source/cmLinkDirectoriesCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLinkDirectoriesCommand_h
-#define cmLinkDirectoriesCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmLinkDirectoriesCommand(std::vector<std::string> const& args,
                               cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmLinkItem.h b/Source/cmLinkItem.h
index 3d92935..5a90e7e 100644
--- a/Source/cmLinkItem.h
+++ b/Source/cmLinkItem.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLinkItem_h
-#define cmLinkItem_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -140,5 +139,3 @@ inline cmTargetLinkLibraryType CMP0003_ComputeLinkType(
   // The current configuration is not a debug configuration.
   return OPTIMIZED_LibraryType;
 }
-
-#endif
diff --git a/Source/cmLinkItemGraphVisitor.cxx b/Source/cmLinkItemGraphVisitor.cxx
index acc23c8..dfdd3ff 100644
--- a/Source/cmLinkItemGraphVisitor.cxx
+++ b/Source/cmLinkItemGraphVisitor.cxx
@@ -24,15 +24,12 @@ void cmLinkItemGraphVisitor::VisitItem(cmLinkItem const& item)
 void cmLinkItemGraphVisitor::VisitLinks(cmLinkItem const& item,
                                         cmLinkItem const& rootItem)
 {
-  if (this->LinkVisited(item, rootItem)) {
-    return;
-  }
-
   if (item.Target == nullptr) {
     return;
   }
 
-  for (auto const& config : item.Target->Makefile->GetGeneratorConfigs()) {
+  for (auto const& config : item.Target->Makefile->GetGeneratorConfigs(
+         cmMakefile::IncludeEmptyConfig)) {
     this->VisitLinks(item, rootItem, config);
   }
 }
diff --git a/Source/cmLinkItemGraphVisitor.h b/Source/cmLinkItemGraphVisitor.h
index 21dc659..0d6676a 100644
--- a/Source/cmLinkItemGraphVisitor.h
+++ b/Source/cmLinkItemGraphVisitor.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLinkItemGraphVisitor_h
-#define cmLinkItemGraphVisitor_h
+#pragma once
 
 #include <map>
 #include <set>
@@ -71,5 +70,3 @@ private:
                               std::string const& config,
                               DependencyMap& dependencies);
 };
-
-#endif
diff --git a/Source/cmLinkLibrariesCommand.h b/Source/cmLinkLibrariesCommand.h
index 3412251..27c410f 100644
--- a/Source/cmLinkLibrariesCommand.h
+++ b/Source/cmLinkLibrariesCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLinkLibrariesCommand_h
-#define cmLinkLibrariesCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmLinkLibrariesCommand(std::vector<std::string> const& args,
                             cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmLinkLineComputer.h b/Source/cmLinkLineComputer.h
index df42468..a1dafc4 100644
--- a/Source/cmLinkLineComputer.h
+++ b/Source/cmLinkLineComputer.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmLinkLineComputer_h
-#define cmLinkLineComputer_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -73,5 +72,3 @@ protected:
   bool UseNinjaMulti;
   bool Relink;
 };
-
-#endif
diff --git a/Source/cmLinkLineDeviceComputer.cxx b/Source/cmLinkLineDeviceComputer.cxx
index c50a786..5739fec 100644
--- a/Source/cmLinkLineDeviceComputer.cxx
+++ b/Source/cmLinkLineDeviceComputer.cxx
@@ -191,21 +191,18 @@ bool requireDeviceLinking(cmGeneratorTarget& target, cmLocalGenerator& lg,
     target.GetLinkClosure(config);
 
   if (cm::contains(closure->Languages, "CUDA")) {
-    if (cmProp separableCompilation =
-          target.GetProperty("CUDA_SEPARABLE_COMPILATION")) {
-      if (cmIsOn(*separableCompilation)) {
-        bool doDeviceLinking = false;
-        switch (target.GetType()) {
-          case cmStateEnums::SHARED_LIBRARY:
-          case cmStateEnums::MODULE_LIBRARY:
-          case cmStateEnums::EXECUTABLE:
-            doDeviceLinking = true;
-            break;
-          default:
-            break;
-        }
-        return doDeviceLinking;
+    if (cmIsOn(target.GetProperty("CUDA_SEPARABLE_COMPILATION"))) {
+      bool doDeviceLinking = false;
+      switch (target.GetType()) {
+        case cmStateEnums::SHARED_LIBRARY:
+        case cmStateEnums::MODULE_LIBRARY:
+        case cmStateEnums::EXECUTABLE:
+          doDeviceLinking = true;
+          break;
+        default:
+          break;
       }
+      return doDeviceLinking;
     }
 
     cmComputeLinkInformation* pcli = target.GetLinkInformation(config);
diff --git a/Source/cmLinkLineDeviceComputer.h b/Source/cmLinkLineDeviceComputer.h
index a9b01cd..dee625b 100644
--- a/Source/cmLinkLineDeviceComputer.h
+++ b/Source/cmLinkLineDeviceComputer.h
@@ -1,8 +1,7 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
 
-#ifndef cmLinkLineDeviceComputer_h
-#define cmLinkLineDeviceComputer_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -42,5 +41,3 @@ public:
 
 bool requireDeviceLinking(cmGeneratorTarget& target, cmLocalGenerator& lg,
                           const std::string& config);
-
-#endif
diff --git a/Source/cmLinkedTree.h b/Source/cmLinkedTree.h
index c7453ea..d70176d 100644
--- a/Source/cmLinkedTree.h
+++ b/Source/cmLinkedTree.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLinkedTree_h
-#define cmLinkedTree_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -188,5 +187,3 @@ private:
   std::vector<T> Data;
   std::vector<PositionType> UpPositions;
 };
-
-#endif
diff --git a/Source/cmListCommand.cxx b/Source/cmListCommand.cxx
index edec613..a2c14bd 100644
--- a/Source/cmListCommand.cxx
+++ b/Source/cmListCommand.cxx
@@ -27,6 +27,7 @@
 #include "cmMakefile.h"
 #include "cmMessageType.h"
 #include "cmPolicies.h"
+#include "cmProperty.h"
 #include "cmRange.h"
 #include "cmStringAlgorithms.h"
 #include "cmStringReplaceHelper.h"
@@ -44,11 +45,11 @@ bool GetListString(std::string& listString, const std::string& var,
                    const cmMakefile& makefile)
 {
   // get the old value
-  const char* cacheValue = makefile.GetDefinition(var);
+  cmProp cacheValue = makefile.GetDefinition(var);
   if (!cacheValue) {
     return false;
   }
-  listString = cacheValue;
+  listString = *cacheValue;
   return true;
 }
 
diff --git a/Source/cmListCommand.h b/Source/cmListCommand.h
index 274d9fd..6efab16 100644
--- a/Source/cmListCommand.h
+++ b/Source/cmListCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmListCommand_h
-#define cmListCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -16,5 +15,3 @@ class cmExecutionStatus;
  */
 bool cmListCommand(std::vector<std::string> const& args,
                    cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmListFileCache.h b/Source/cmListFileCache.h
index 89902ff..c9556ab 100644
--- a/Source/cmListFileCache.h
+++ b/Source/cmListFileCache.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmListFileCache_h
-#define cmListFileCache_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -175,6 +174,32 @@ public:
 
 std::ostream& operator<<(std::ostream& os, BT<std::string> const& s);
 
+// Wrap type T as a value with potentially multiple backtraces.  For purposes
+// of ordering and equality comparison, only the original value is used.  The
+// backtrace is considered incidental.
+template <typename T>
+class BTs
+{
+public:
+  BTs(T v = T(), cmListFileBacktrace bt = cmListFileBacktrace())
+    : Value(std::move(v))
+  {
+    Backtraces.emplace_back(std::move(bt));
+  }
+  T Value;
+  std::vector<cmListFileBacktrace> Backtraces;
+  friend bool operator==(BTs<T> const& l, BTs<T> const& r)
+  {
+    return l.Value == r.Value;
+  }
+  friend bool operator<(BTs<T> const& l, BTs<T> const& r)
+  {
+    return l.Value < r.Value;
+  }
+  friend bool operator==(BTs<T> const& l, T const& r) { return l.Value == r; }
+  friend bool operator==(T const& l, BTs<T> const& r) { return l == r.Value; }
+};
+
 std::vector<BT<std::string>> ExpandListWithBacktrace(
   std::string const& list,
   cmListFileBacktrace const& bt = cmListFileBacktrace());
@@ -189,5 +214,3 @@ struct cmListFile
 
   std::vector<cmListFileFunction> Functions;
 };
-
-#endif
diff --git a/Source/cmListFileLexer.h b/Source/cmListFileLexer.h
index ec6b3cd..3c89f63 100644
--- a/Source/cmListFileLexer.h
+++ b/Source/cmListFileLexer.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmListFileLexer_h
-#define cmListFileLexer_h
+#pragma once
 
 #ifdef __cplusplus
 extern "C" {
@@ -67,5 +66,3 @@ void cmListFileLexer_Delete(cmListFileLexer*);
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
-
-#endif
diff --git a/Source/cmLoadCacheCommand.h b/Source/cmLoadCacheCommand.h
index 7cee663..5f5b705 100644
--- a/Source/cmLoadCacheCommand.h
+++ b/Source/cmLoadCacheCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLoadCacheCommand_h
-#define cmLoadCacheCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmLoadCacheCommand(std::vector<std::string> const& args,
                         cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmLoadCommandCommand.h b/Source/cmLoadCommandCommand.h
index f5fd754..d30ba16 100644
--- a/Source/cmLoadCommandCommand.h
+++ b/Source/cmLoadCommandCommand.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLoadCommandCommand_h
-#define cmLoadCommandCommand_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -12,5 +11,3 @@ class cmExecutionStatus;
 
 bool cmLoadCommandCommand(std::vector<std::string> const& args,
                           cmExecutionStatus& status);
-
-#endif
diff --git a/Source/cmLocalCommonGenerator.cxx b/Source/cmLocalCommonGenerator.cxx
index 278ec8b..5daaeff 100644
--- a/Source/cmLocalCommonGenerator.cxx
+++ b/Source/cmLocalCommonGenerator.cxx
@@ -8,6 +8,7 @@
 #include "cmGeneratorTarget.h"
 #include "cmMakefile.h"
 #include "cmOutputConverter.h"
+#include "cmProperty.h"
 #include "cmStringAlgorithms.h"
 
 class cmGlobalGenerator;
@@ -17,10 +18,8 @@ cmLocalCommonGenerator::cmLocalCommonGenerator(cmGlobalGenerator* gg,
   : cmLocalGenerator(gg, mf)
   , WorkingDirectory(std::move(wd))
 {
-  this->Makefile->GetConfigurations(this->ConfigNames);
-  if (this->ConfigNames.empty()) {
-    this->ConfigNames.emplace_back();
-  }
+  this->ConfigNames =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 }
 
 cmLocalCommonGenerator::~cmLocalCommonGenerator() = default;
@@ -64,13 +63,13 @@ std::string cmLocalCommonGenerator::GetTargetFortranFlags(
   // If there is a separate module path flag then duplicate the
   // include path with it.  This compiler does not search the include
   // path for modules.
-  if (const char* modpath_flag =
+  if (cmProp modpath_flag =
         this->Makefile->GetDefinition("CMAKE_Fortran_MODPATH_FLAG")) {
     std::vector<std::string> includes;
     this->GetIncludeDirectories(includes, target, "C", config);
     for (std::string const& id : includes) {
       std::string flg =
-        cmStrCat(modpath_flag,
+        cmStrCat(*modpath_flag,
                  this->ConvertToOutputFormat(id, cmOutputConverter::SHELL));
       this->AppendFlags(flags, flg);
     }
diff --git a/Source/cmLocalCommonGenerator.h b/Source/cmLocalCommonGenerator.h
index 378ca63..f1eaf61 100644
--- a/Source/cmLocalCommonGenerator.h
+++ b/Source/cmLocalCommonGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLocalCommonGenerator_h
-#define cmLocalCommonGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -47,5 +46,3 @@ protected:
 
   friend class cmCommonTargetGenerator;
 };
-
-#endif
diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index c15ca7c..47931b0 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -39,6 +39,7 @@
 #include "cmSourceFile.h"
 #include "cmSourceFileLocation.h"
 #include "cmSourceFileLocationKind.h"
+#include "cmStandardLevelResolver.h"
 #include "cmState.h"
 #include "cmStateDirectory.h"
 #include "cmStateTypes.h"
@@ -115,22 +116,22 @@ cmLocalGenerator::cmLocalGenerator(cmGlobalGenerator* gg, cmMakefile* makefile)
   std::vector<std::string> enabledLanguages =
     this->GetState()->GetEnabledLanguages();
 
-  if (const char* sysrootCompile =
+  if (cmProp sysrootCompile =
         this->Makefile->GetDefinition("CMAKE_SYSROOT_COMPILE")) {
-    this->CompilerSysroot = sysrootCompile;
+    this->CompilerSysroot = *sysrootCompile;
   } else {
     this->CompilerSysroot = this->Makefile->GetSafeDefinition("CMAKE_SYSROOT");
   }
 
-  if (const char* sysrootLink =
+  if (cmProp sysrootLink =
         this->Makefile->GetDefinition("CMAKE_SYSROOT_LINK")) {
-    this->LinkerSysroot = sysrootLink;
+    this->LinkerSysroot = *sysrootLink;
   } else {
     this->LinkerSysroot = this->Makefile->GetSafeDefinition("CMAKE_SYSROOT");
   }
 
-  if (std::string const* appleArchSysroots =
-        this->Makefile->GetDef("CMAKE_APPLE_ARCH_SYSROOTS")) {
+  if (cmProp appleArchSysroots =
+        this->Makefile->GetDefinition("CMAKE_APPLE_ARCH_SYSROOTS")) {
     std::string const& appleArchs =
       this->Makefile->GetSafeDefinition("CMAKE_OSX_ARCHITECTURES");
     std::vector<std::string> archs;
@@ -219,10 +220,10 @@ void cmLocalGenerator::ComputeObjectMaxPath()
 #else
   this->ObjectPathMax = 1000;
 #endif
-  const char* plen = this->Makefile->GetDefinition("CMAKE_OBJECT_PATH_MAX");
-  if (plen && *plen) {
+  cmProp plen = this->Makefile->GetDefinition("CMAKE_OBJECT_PATH_MAX");
+  if (cmNonempty(plen)) {
     unsigned int pmax;
-    if (sscanf(plen, "%u", &pmax) == 1) {
+    if (sscanf(plen->c_str(), "%u", &pmax) == 1) {
       if (pmax >= 128) {
         this->ObjectPathMax = pmax;
       } else {
@@ -234,7 +235,7 @@ void cmLocalGenerator::ComputeObjectMaxPath()
       }
     } else {
       std::ostringstream w;
-      w << "CMAKE_OBJECT_PATH_MAX is set to \"" << plen
+      w << "CMAKE_OBJECT_PATH_MAX is set to \"" << *plen
         << "\", which fails to parse as a positive integer.  "
         << "The value will be ignored.";
       this->IssueMessage(MessageType::AUTHOR_WARNING, w.str());
@@ -283,7 +284,7 @@ void cmLocalGenerator::TraceDependencies()
   // Generate the rule files for each target.
   const auto& targets = this->GetGeneratorTargets();
   for (const auto& target : targets) {
-    if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!target->IsInBuildSystem()) {
       continue;
     }
     target->TraceDependencies();
@@ -297,9 +298,9 @@ void cmLocalGenerator::GenerateTestFiles()
   }
 
   // Compute the set of configurations.
-  std::vector<std::string> configurationTypes;
-  const std::string& config =
-    this->Makefile->GetConfigurations(configurationTypes, false);
+  std::vector<std::string> configurationTypes =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::OnlyMultiConfig);
+  std::string config = this->Makefile->GetDefaultConfiguration();
 
   std::string file =
     cmStrCat(this->StateSnapshot.GetDirectory().GetCurrentBinary(),
@@ -357,7 +358,7 @@ void cmLocalGenerator::GenerateTestFiles()
   }
 
   // Add directory labels property
-  const char* directoryLabels =
+  cmProp directoryLabels =
     this->Makefile->GetDefinition("CMAKE_DIRECTORY_LABELS");
   cmProp labels = this->Makefile->GetProperty("LABELS");
 
@@ -370,7 +371,7 @@ void cmLocalGenerator::GenerateTestFiles()
       fout << ";";
     }
     if (directoryLabels) {
-      fout << cmOutputConverter::EscapeForCMake(directoryLabels);
+      fout << cmOutputConverter::EscapeForCMake(*directoryLabels);
     }
     fout << ")\n";
   }
@@ -379,7 +380,7 @@ void cmLocalGenerator::GenerateTestFiles()
 void cmLocalGenerator::CreateEvaluationFileOutputs()
 {
   std::vector<std::string> const& configs =
-    this->Makefile->GetGeneratorConfigs();
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
   for (std::string const& c : configs) {
     this->CreateEvaluationFileOutputs(c);
   }
@@ -424,7 +425,8 @@ void cmLocalGenerator::ProcessEvaluationFiles(
 void cmLocalGenerator::GenerateInstallRules()
 {
   // Compute the install prefix.
-  const char* prefix = this->Makefile->GetDefinition("CMAKE_INSTALL_PREFIX");
+  const char* prefix =
+    cmToCStr(this->Makefile->GetDefinition("CMAKE_INSTALL_PREFIX"));
 
 #if defined(_WIN32) && !defined(__CYGWIN__)
   std::string prefix_win32;
@@ -432,10 +434,10 @@ void cmLocalGenerator::GenerateInstallRules()
     if (!cmSystemTools::GetEnv("SystemDrive", prefix_win32)) {
       prefix_win32 = "C:";
     }
-    const char* project_name = this->Makefile->GetDefinition("PROJECT_NAME");
-    if (project_name && project_name[0]) {
+    cmProp project_name = this->Makefile->GetDefinition("PROJECT_NAME");
+    if (cmNonempty(project_name)) {
       prefix_win32 += "/Program Files/";
-      prefix_win32 += project_name;
+      prefix_win32 += *project_name;
     } else {
       prefix_win32 += "/InstalledCMakeProject";
     }
@@ -456,15 +458,15 @@ void cmLocalGenerator::GenerateInstallRules()
     prefix = "/usr/local";
   }
 #endif
-  if (const char* stagingPrefix =
+  if (cmProp stagingPrefix =
         this->Makefile->GetDefinition("CMAKE_STAGING_PREFIX")) {
-    prefix = stagingPrefix;
+    prefix = stagingPrefix->c_str();
   }
 
   // Compute the set of configurations.
-  std::vector<std::string> configurationTypes;
-  const std::string& config =
-    this->Makefile->GetConfigurations(configurationTypes, false);
+  std::vector<std::string> configurationTypes =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::OnlyMultiConfig);
+  std::string config = this->Makefile->GetDefaultConfiguration();
 
   // Choose a default install configuration.
   std::string default_config = config;
@@ -538,40 +540,40 @@ void cmLocalGenerator::GenerateInstallRules()
   /* clang-format on */
 
   // Copy user-specified install options to the install code.
-  if (const char* so_no_exe =
+  if (cmProp so_no_exe =
         this->Makefile->GetDefinition("CMAKE_INSTALL_SO_NO_EXE")) {
     /* clang-format off */
     fout <<
       "# Install shared libraries without execute permission?\n"
       "if(NOT DEFINED CMAKE_INSTALL_SO_NO_EXE)\n"
-      "  set(CMAKE_INSTALL_SO_NO_EXE \"" << so_no_exe << "\")\n"
+      "  set(CMAKE_INSTALL_SO_NO_EXE \"" << *so_no_exe << "\")\n"
       "endif()\n"
       "\n";
     /* clang-format on */
   }
 
   // Copy cmake cross compile state to install code.
-  if (const char* crosscompiling =
+  if (cmProp crosscompiling =
         this->Makefile->GetDefinition("CMAKE_CROSSCOMPILING")) {
     /* clang-format off */
     fout <<
       "# Is this installation the result of a crosscompile?\n"
       "if(NOT DEFINED CMAKE_CROSSCOMPILING)\n"
-      "  set(CMAKE_CROSSCOMPILING \"" << crosscompiling << "\")\n"
+      "  set(CMAKE_CROSSCOMPILING \"" << *crosscompiling << "\")\n"
       "endif()\n"
       "\n";
     /* clang-format on */
   }
 
   // Write default directory permissions.
-  if (const char* defaultDirPermissions = this->Makefile->GetDefinition(
+  if (cmProp defaultDirPermissions = this->Makefile->GetDefinition(
         "CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS")) {
     /* clang-format off */
     fout <<
       "# Set default install directory permissions.\n"
       "if(NOT DEFINED CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS)\n"
       "  set(CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS \""
-         << defaultDirPermissions << "\")\n"
+         << *defaultDirPermissions << "\")\n"
       "endif()\n"
       "\n";
     /* clang-format on */
@@ -580,14 +582,14 @@ void cmLocalGenerator::GenerateInstallRules()
   // Write out CMAKE_GET_RUNTIME_DEPENDENCIES_PLATFORM so that
   // installed code that uses `file(GET_RUNTIME_DEPENDENCIES)`
   // has same platform variable as when running cmake
-  if (const char* platform = this->Makefile->GetDefinition(
+  if (cmProp platform = this->Makefile->GetDefinition(
         "CMAKE_GET_RUNTIME_DEPENDENCIES_PLATFORM")) {
     /* clang-format off */
     fout <<
       "# Set default install directory permissions.\n"
       "if(NOT DEFINED CMAKE_GET_RUNTIME_DEPENDENCIES_PLATFORM)\n"
       "  set(CMAKE_GET_RUNTIME_DEPENDENCIES_PLATFORM \""
-         << platform << "\")\n"
+         << *platform << "\")\n"
       "endif()\n"
       "\n";
     /* clang-format on */
@@ -596,14 +598,14 @@ void cmLocalGenerator::GenerateInstallRules()
   // Write out CMAKE_GET_RUNTIME_DEPENDENCIES_TOOL so that
   // installed code that uses `file(GET_RUNTIME_DEPENDENCIES)`
   // has same tool selected as when running cmake
-  if (const char* command =
+  if (cmProp command =
         this->Makefile->GetDefinition("CMAKE_GET_RUNTIME_DEPENDENCIES_TOOL")) {
     /* clang-format off */
     fout <<
       "# Set default install directory permissions.\n"
       "if(NOT DEFINED CMAKE_GET_RUNTIME_DEPENDENCIES_TOOL)\n"
       "  set(CMAKE_GET_RUNTIME_DEPENDENCIES_TOOL \""
-         << command << "\")\n"
+         << *command << "\")\n"
       "endif()\n"
       "\n";
     /* clang-format on */
@@ -612,14 +614,14 @@ void cmLocalGenerator::GenerateInstallRules()
   // Write out CMAKE_GET_RUNTIME_DEPENDENCIES_COMMAND so that
   // installed code that uses `file(GET_RUNTIME_DEPENDENCIES)`
   // has same path to the tool as when running cmake
-  if (const char* command = this->Makefile->GetDefinition(
+  if (cmProp command = this->Makefile->GetDefinition(
         "CMAKE_GET_RUNTIME_DEPENDENCIES_COMMAND")) {
     /* clang-format off */
     fout <<
       "# Set default install directory permissions.\n"
       "if(NOT DEFINED CMAKE_GET_RUNTIME_DEPENDENCIES_COMMAND)\n"
       "  set(CMAKE_GET_RUNTIME_DEPENDENCIES_COMMAND \""
-         << command << "\")\n"
+         << *command << "\")\n"
       "endif()\n"
       "\n";
     /* clang-format on */
@@ -630,13 +632,13 @@ void cmLocalGenerator::GenerateInstallRules()
   // CMAKE_GET_RUNTIME_DEPENDENCIES_COMMAND has consistent
   // logic to fallback to CMAKE_OBJDUMP when `objdump` is
   // not on the path
-  if (const char* command = this->Makefile->GetDefinition("CMAKE_OBJDUMP")) {
+  if (cmProp command = this->Makefile->GetDefinition("CMAKE_OBJDUMP")) {
     /* clang-format off */
     fout <<
       "# Set default install directory permissions.\n"
       "if(NOT DEFINED CMAKE_OBJDUMP)\n"
       "  set(CMAKE_OBJDUMP \""
-         << command << "\")\n"
+         << *command << "\")\n"
       "endif()\n"
       "\n";
     /* clang-format on */
@@ -753,16 +755,13 @@ cmGeneratorTarget* cmLocalGenerator::FindLocalNonAliasGeneratorTarget(
 void cmLocalGenerator::ComputeTargetManifest()
 {
   // Collect the set of configuration types.
-  std::vector<std::string> configNames;
-  this->Makefile->GetConfigurations(configNames);
-  if (configNames.empty()) {
-    configNames.emplace_back();
-  }
+  std::vector<std::string> configNames =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
   // Add our targets to the manifest for each configuration.
   const auto& targets = this->GetGeneratorTargets();
   for (const auto& target : targets) {
-    if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!target->IsInBuildSystem()) {
       continue;
     }
     for (std::string const& c : configNames) {
@@ -774,11 +773,8 @@ void cmLocalGenerator::ComputeTargetManifest()
 bool cmLocalGenerator::ComputeTargetCompileFeatures()
 {
   // Collect the set of configuration types.
-  std::vector<std::string> configNames;
-  this->Makefile->GetConfigurations(configNames);
-  if (configNames.empty()) {
-    configNames.emplace_back();
-  }
+  std::vector<std::string> configNames =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
   using LanguagePair = std::pair<std::string, std::string>;
   std::vector<LanguagePair> pairedLanguages{ { "OBJC", "C" },
@@ -802,40 +798,9 @@ bool cmLocalGenerator::ComputeTargetCompileFeatures()
 
     // Now that C/C++ _STANDARD values have been computed
     // set the values to ObjC/ObjCXX _STANDARD variables
-    if (target->GetType() != cmStateEnums::INTERFACE_LIBRARY) {
-      auto copyStandardToObjLang = [&](LanguagePair const& lang) -> bool {
-        if (!target->GetProperty(cmStrCat(lang.first, "_STANDARD"))) {
-          cmProp standard =
-            target->GetProperty(cmStrCat(lang.second, "_STANDARD"));
-          if (!standard) {
-            standard = this->Makefile->GetDef(
-              cmStrCat("CMAKE_", lang.second, "_STANDARD_DEFAULT"));
-          }
-          target->Target->SetProperty(cmStrCat(lang.first, "_STANDARD"),
-                                      standard ? standard->c_str() : nullptr);
-          return true;
-        }
-        return false;
-      };
-      auto copyPropertyToObjLang = [&](LanguagePair const& lang,
-                                       const char* property) {
-        if (!target->GetProperty(cmStrCat(lang.first, property)) &&
-            target->GetProperty(cmStrCat(lang.second, property))) {
-          cmProp p = target->GetProperty(cmStrCat(lang.second, property));
-          target->Target->SetProperty(cmStrCat(lang.first, property),
-                                      p ? p->c_str() : nullptr);
-        }
-      };
-      for (auto const& lang : pairedLanguages) {
-        if (copyStandardToObjLang(lang)) {
-          copyPropertyToObjLang(lang, "_STANDARD_REQUIRED");
-          copyPropertyToObjLang(lang, "_EXTENSIONS");
-        }
-      }
-      if (cmProp standard = target->GetProperty("CUDA_STANDARD")) {
-        if (*standard == "98") {
-          target->Target->SetProperty("CUDA_STANDARD", "03");
-        }
+    if (target->CanCompileSources()) {
+      for (std::string const& c : configNames) {
+        target->ComputeCompileFeatures(c, inferredEnabledLanguages);
       }
     }
   }
@@ -894,8 +859,8 @@ std::string cmLocalGenerator::GetIncludeFlags(
 
   std::string const& includeFlag =
     this->Makefile->GetSafeDefinition(cmStrCat("CMAKE_INCLUDE_FLAG_", lang));
-  const char* sep =
-    this->Makefile->GetDefinition(cmStrCat("CMAKE_INCLUDE_FLAG_SEP_", lang));
+  const char* sep = cmToCStr(
+    this->Makefile->GetDefinition(cmStrCat("CMAKE_INCLUDE_FLAG_SEP_", lang)));
   bool quotePaths = false;
   if (this->Makefile->GetDefinition("CMAKE_QUOTE_INCLUDE_PATHS")) {
     quotePaths = true;
@@ -912,15 +877,15 @@ std::string cmLocalGenerator::GetIncludeFlags(
 
   // Support special system include flag if it is available and the
   // normal flag is repeated for each directory.
-  const char* sysIncludeFlag = nullptr;
+  cmProp sysIncludeFlag = nullptr;
   if (repeatFlag) {
     sysIncludeFlag = this->Makefile->GetDefinition(
       cmStrCat("CMAKE_INCLUDE_SYSTEM_FLAG_", lang));
   }
 
-  const char* fwSearchFlag = this->Makefile->GetDefinition(
+  cmProp fwSearchFlag = this->Makefile->GetDefinition(
     cmStrCat("CMAKE_", lang, "_FRAMEWORK_SEARCH_FLAG"));
-  const char* sysFwSearchFlag = this->Makefile->GetDefinition(
+  cmProp sysFwSearchFlag = this->Makefile->GetDefinition(
     cmStrCat("CMAKE_", lang, "_SYSTEM_FRAMEWORK_SEARCH_FLAG"));
 
   bool flagUsed = false;
@@ -929,16 +894,16 @@ std::string cmLocalGenerator::GetIncludeFlags(
   emitted.insert("/System/Library/Frameworks");
 #endif
   for (std::string const& i : includes) {
-    if (fwSearchFlag && *fwSearchFlag && this->Makefile->IsOn("APPLE") &&
+    if (cmNonempty(fwSearchFlag) && this->Makefile->IsOn("APPLE") &&
         cmSystemTools::IsPathToFramework(i)) {
       std::string const frameworkDir =
         cmSystemTools::CollapseFullPath(cmStrCat(i, "/../"));
       if (emitted.insert(frameworkDir).second) {
         if (sysFwSearchFlag && target &&
             target->IsSystemIncludeDirectory(i, config, lang)) {
-          includeFlags << sysFwSearchFlag;
+          includeFlags << *sysFwSearchFlag;
         } else {
-          includeFlags << fwSearchFlag;
+          includeFlags << *fwSearchFlag;
         }
         includeFlags << this->ConvertToOutputFormat(frameworkDir, shellFormat)
                      << " ";
@@ -949,7 +914,7 @@ std::string cmLocalGenerator::GetIncludeFlags(
     if (!flagUsed || repeatFlag) {
       if (sysIncludeFlag && target &&
           target->IsSystemIncludeDirectory(i, config, lang)) {
-        includeFlags << sysIncludeFlag;
+        includeFlags << *sysIncludeFlag;
       } else {
         includeFlags << includeFlag;
       }
@@ -989,9 +954,9 @@ void cmLocalGenerator::AddCompileOptions(std::vector<BT<std::string>>& flags,
                                          const std::string& lang,
                                          const std::string& config)
 {
-  std::string langFlagRegexVar = std::string("CMAKE_") + lang + "_FLAG_REGEX";
+  std::string langFlagRegexVar = cmStrCat("CMAKE_", lang, "_FLAG_REGEX");
 
-  if (const char* langFlagRegexStr =
+  if (cmProp langFlagRegexStr =
         this->Makefile->GetDefinition(langFlagRegexVar)) {
     // Filter flags acceptable to this language.
     if (cmProp targetFlags = target->GetProperty("COMPILE_FLAGS")) {
@@ -1000,7 +965,7 @@ void cmLocalGenerator::AddCompileOptions(std::vector<BT<std::string>>& flags,
       // Re-escape these flags since COMPILE_FLAGS were already parsed
       // as a command line above.
       std::string compileOpts;
-      this->AppendCompileOptions(compileOpts, opts, langFlagRegexStr);
+      this->AppendCompileOptions(compileOpts, opts, langFlagRegexStr->c_str());
       if (!compileOpts.empty()) {
         flags.emplace_back(std::move(compileOpts));
       }
@@ -1008,7 +973,8 @@ void cmLocalGenerator::AddCompileOptions(std::vector<BT<std::string>>& flags,
     std::vector<BT<std::string>> targetCompileOpts =
       target->GetCompileOptions(config, lang);
     // COMPILE_OPTIONS are escaped.
-    this->AppendCompileOptions(flags, targetCompileOpts, langFlagRegexStr);
+    this->AppendCompileOptions(flags, targetCompileOpts,
+                               langFlagRegexStr->c_str());
   } else {
     // Use all flags.
     if (cmProp targetFlags = target->GetProperty("COMPILE_FLAGS")) {
@@ -1025,12 +991,13 @@ void cmLocalGenerator::AddCompileOptions(std::vector<BT<std::string>>& flags,
     this->AppendCompileOptions(flags, targetCompileOpts);
   }
 
+  cmStandardLevelResolver standardResolver(this->Makefile);
   for (auto const& it : target->GetMaxLanguageStandards()) {
-    cmProp standard = target->GetProperty(it.first + "_STANDARD");
+    cmProp standard = target->GetLanguageStandard(it.first, config);
     if (!standard) {
       continue;
     }
-    if (this->Makefile->IsLaterStandard(it.first, *standard, it.second)) {
+    if (standardResolver.IsLaterStandard(it.first, *standard, it.second)) {
       std::ostringstream e;
       e << "The COMPILE_FEATURES property of target \"" << target->GetName()
         << "\" was evaluated when computing the link "
@@ -1050,14 +1017,14 @@ void cmLocalGenerator::AddCompileOptions(std::vector<BT<std::string>>& flags,
   }
 
   std::string compReqFlag;
-  this->AddCompilerRequirementFlag(compReqFlag, target, lang);
+  this->AddCompilerRequirementFlag(compReqFlag, target, lang, config);
   if (!compReqFlag.empty()) {
     flags.emplace_back(std::move(compReqFlag));
   }
 
   // Add compile flag for the MSVC compiler only.
   cmMakefile* mf = this->GetMakefile();
-  if (const char* jmc =
+  if (cmProp jmc =
         mf->GetDefinition("CMAKE_" + lang + "_COMPILE_OPTIONS_JMC")) {
 
     // Handle Just My Code debugging flags, /JMC.
@@ -1071,7 +1038,7 @@ void cmLocalGenerator::AddCompileOptions(std::vector<BT<std::string>>& flags,
         std::string isJMCEnabled =
           cmGeneratorExpression::Evaluate(*jmcExprGen, this, config);
         if (cmIsOn(isJMCEnabled)) {
-          std::vector<std::string> optVec = cmExpandedList(jmc);
+          std::vector<std::string> optVec = cmExpandedList(*jmc);
           std::string jmcFlags;
           this->AppendCompileOptions(jmcFlags, optVec);
           if (!jmcFlags.empty()) {
@@ -1308,7 +1275,7 @@ std::vector<BT<std::string>> cmLocalGenerator::GetIncludeDirectoriesImplicit(
     }
   }
 
-  // Emit remaining non implicit user direcories.
+  // Emit remaining non implicit user directories.
   for (BT<std::string> const& udr : userDirs) {
     if (notExcluded(udr.Value)) {
       emitBT(udr);
@@ -1555,7 +1522,7 @@ void cmLocalGenerator::GetTargetFlags(
           return;
         }
 
-        if (target->GetPropertyAsBool("WIN32_EXECUTABLE")) {
+        if (target->IsWin32Executable(config)) {
           exeFlags +=
             this->Makefile->GetSafeDefinition("CMAKE_CREATE_WIN32_EXE");
           exeFlags += " ";
@@ -1578,9 +1545,8 @@ void cmLocalGenerator::GetTargetFlags(
                                   frameworkPath, linkPath);
       }
 
-      if (cmIsOn(this->Makefile->GetDefinition("BUILD_SHARED_LIBS"))) {
-        std::string sFlagVar = std::string("CMAKE_SHARED_BUILD_") +
-          linkLanguage + std::string("_FLAGS");
+      if (this->Makefile->IsOn("BUILD_SHARED_LIBS")) {
+        std::string sFlagVar = "CMAKE_SHARED_BUILD_" + linkLanguage + "_FLAGS";
         exeFlags += this->Makefile->GetSafeDefinition(sFlagVar);
         exeFlags += " ";
       }
@@ -1688,8 +1654,8 @@ static std::string GetFrameworkFlags(const std::string& lang,
   }
 
   std::string fwSearchFlagVar = "CMAKE_" + lang + "_FRAMEWORK_SEARCH_FLAG";
-  const char* fwSearchFlag = mf->GetDefinition(fwSearchFlagVar);
-  if (!(fwSearchFlag && *fwSearchFlag)) {
+  cmProp fwSearchFlag = mf->GetDefinition(fwSearchFlagVar);
+  if (!cmNonempty(fwSearchFlag)) {
     return std::string();
   }
 
@@ -1715,7 +1681,7 @@ static std::string GetFrameworkFlags(const std::string& lang,
     std::vector<std::string> const& frameworks = cli->GetFrameworkPaths();
     for (std::string const& framework : frameworks) {
       if (emitted.insert(framework).second) {
-        flags += fwSearchFlag;
+        flags += *fwSearchFlag;
         flags +=
           lg->ConvertToOutputFormat(framework, cmOutputConverter::SHELL);
         flags += " ";
@@ -1797,18 +1763,18 @@ void cmLocalGenerator::OutputLinkLibraries(
   std::string linkLanguage = cli.GetLinkLanguage();
 
   std::string libPathFlag;
-  if (const char* value = this->Makefile->GetDefinition(
+  if (cmProp value = this->Makefile->GetDefinition(
         "CMAKE_" + cli.GetLinkLanguage() + "_LIBRARY_PATH_FLAG")) {
-    libPathFlag = value;
+    libPathFlag = *value;
   } else {
     libPathFlag =
       this->Makefile->GetRequiredDefinition("CMAKE_LIBRARY_PATH_FLAG");
   }
 
   std::string libPathTerminator;
-  if (const char* value = this->Makefile->GetDefinition(
+  if (cmProp value = this->Makefile->GetDefinition(
         "CMAKE_" + cli.GetLinkLanguage() + "_LIBRARY_PATH_TERMINATOR")) {
-    libPathTerminator = value;
+    libPathTerminator = *value;
   } else {
     libPathTerminator =
       this->Makefile->GetRequiredDefinition("CMAKE_LIBRARY_PATH_TERMINATOR");
@@ -1911,8 +1877,9 @@ void cmLocalGenerator::AddArchitectureFlags(std::string& flags,
   if (this->Makefile->IsOn("APPLE") && this->EmitUniversalBinaryFlags) {
     std::vector<std::string> archs;
     target->GetAppleArchs(config, archs);
-    if (!archs.empty() && !lang.empty() &&
-        (lang[0] == 'C' || lang[0] == 'F' || lang[0] == 'O')) {
+    if (!archs.empty() &&
+        (lang == "C" || lang == "CXX" || lang == "OBJ" || lang == "OBJCXX" ||
+         cmHasLiteralPrefix(lang, "ASM"))) {
       for (std::string const& arch : archs) {
         if (filterArch.empty() || filterArch == arch) {
           flags += " -arch ";
@@ -1921,16 +1888,15 @@ void cmLocalGenerator::AddArchitectureFlags(std::string& flags,
       }
     }
 
-    const char* sysroot = this->Makefile->GetDefinition("CMAKE_OSX_SYSROOT");
-    if (sysroot && sysroot[0] == '/' && !sysroot[1]) {
+    cmProp sysroot = this->Makefile->GetDefinition("CMAKE_OSX_SYSROOT");
+    if (sysroot && *sysroot == "/") {
       sysroot = nullptr;
     }
-    std::string sysrootFlagVar =
-      std::string("CMAKE_") + lang + "_SYSROOT_FLAG";
-    const char* sysrootFlag = this->Makefile->GetDefinition(sysrootFlagVar);
-    if (sysrootFlag && *sysrootFlag) {
+    std::string sysrootFlagVar = "CMAKE_" + lang + "_SYSROOT_FLAG";
+    cmProp sysrootFlag = this->Makefile->GetDefinition(sysrootFlagVar);
+    if (cmNonempty(sysrootFlag)) {
       if (!this->AppleArchSysroots.empty() &&
-          !this->AllAppleArchSysrootsAreTheSame(archs, sysroot)) {
+          !this->AllAppleArchSysrootsAreTheSame(archs, cmToCStr(sysroot))) {
         for (std::string const& arch : archs) {
           std::string const& archSysroot = this->AppleArchSysroots[arch];
           if (cmIsOff(archSysroot)) {
@@ -1939,29 +1905,28 @@ void cmLocalGenerator::AddArchitectureFlags(std::string& flags,
           if (filterArch.empty() || filterArch == arch) {
             flags += " -Xarch_" + arch + " ";
             // Combine sysroot flag and path to work with -Xarch
-            std::string arch_sysroot = sysrootFlag + archSysroot;
+            std::string arch_sysroot = *sysrootFlag + archSysroot;
             flags += this->ConvertToOutputFormat(arch_sysroot, SHELL);
           }
         }
-      } else if (sysroot && *sysroot) {
+      } else if (cmNonempty(sysroot)) {
         flags += " ";
-        flags += sysrootFlag;
+        flags += *sysrootFlag;
         flags += " ";
-        flags += this->ConvertToOutputFormat(sysroot, SHELL);
+        flags += this->ConvertToOutputFormat(*sysroot, SHELL);
       }
     }
 
-    const char* deploymentTarget =
+    cmProp deploymentTarget =
       this->Makefile->GetDefinition("CMAKE_OSX_DEPLOYMENT_TARGET");
     std::string deploymentTargetFlagVar =
-      std::string("CMAKE_") + lang + "_OSX_DEPLOYMENT_TARGET_FLAG";
-    const char* deploymentTargetFlag =
+      "CMAKE_" + lang + "_OSX_DEPLOYMENT_TARGET_FLAG";
+    cmProp deploymentTargetFlag =
       this->Makefile->GetDefinition(deploymentTargetFlagVar);
-    if (deploymentTargetFlag && *deploymentTargetFlag && deploymentTarget &&
-        *deploymentTarget) {
+    if (cmNonempty(deploymentTargetFlag) && cmNonempty(deploymentTarget)) {
       flags += " ";
-      flags += deploymentTargetFlag;
-      flags += deploymentTarget;
+      flags += *deploymentTargetFlag;
+      flags += *deploymentTarget;
     }
   }
 }
@@ -1975,12 +1940,15 @@ void cmLocalGenerator::AddLanguageFlags(std::string& flags,
   this->AddConfigVariableFlags(flags, cmStrCat("CMAKE_", lang, "_FLAGS"),
                                config);
 
+  std::string const& compiler = this->Makefile->GetSafeDefinition(
+    cmStrCat("CMAKE_", lang, "_COMPILER_ID"));
+
   if (lang == "Swift") {
     if (cmProp v = target->GetProperty("Swift_LANGUAGE_VERSION")) {
-      if (cmSystemTools::VersionCompare(
-            cmSystemTools::OP_GREATER_EQUAL,
-            this->Makefile->GetDefinition("CMAKE_Swift_COMPILER_VERSION"),
-            "4.2")) {
+      if (cmSystemTools::VersionCompare(cmSystemTools::OP_GREATER_EQUAL,
+                                        cmToCStr(this->Makefile->GetDefinition(
+                                          "CMAKE_Swift_COMPILER_VERSION")),
+                                        "4.2")) {
         this->AppendFlags(flags, "-swift-version " + *v);
       }
     }
@@ -1988,9 +1956,6 @@ void cmLocalGenerator::AddLanguageFlags(std::string& flags,
     target->AddCUDAArchitectureFlags(flags);
     target->AddCUDAToolkitFlags(flags);
 
-    std::string const& compiler =
-      this->Makefile->GetSafeDefinition("CMAKE_CUDA_COMPILER_ID");
-
     if (compiler == "Clang") {
       bool separable = target->GetPropertyAsBool("CUDA_SEPARABLE_COMPILATION");
 
@@ -2001,13 +1966,32 @@ void cmLocalGenerator::AddLanguageFlags(std::string& flags,
           "See CMake issue #20726.");
       }
     }
+  } else if (lang == "ISPC") {
+    target->AddISPCTargetFlags(flags);
+  }
+  // Add VFS Overlay for Clang compiliers
+  if (compiler == "Clang") {
+    if (cmProp vfsOverlay =
+          this->Makefile->GetDefinition("CMAKE_CLANG_VFS_OVERLAY")) {
+      std::string const& compilerSimulateId =
+        this->Makefile->GetSafeDefinition(
+          cmStrCat("CMAKE_", lang, "_SIMULATE_ID"));
+      if (compilerSimulateId == "MSVC") {
+        this->AppendCompileOptions(
+          flags,
+          std::vector<std::string>{ "-Xclang", "-ivfsoverlay", "-Xclang",
+                                    *vfsOverlay });
+      } else {
+        this->AppendCompileOptions(
+          flags, std::vector<std::string>{ "-ivfsoverlay", *vfsOverlay });
+      }
+    }
   }
-
   // Add MSVC runtime library flags.  This is activated by the presence
   // of a default selection whether or not it is overridden by a property.
   cmProp msvcRuntimeLibraryDefault =
-    this->Makefile->GetDef("CMAKE_MSVC_RUNTIME_LIBRARY_DEFAULT");
-  if (msvcRuntimeLibraryDefault && !msvcRuntimeLibraryDefault->empty()) {
+    this->Makefile->GetDefinition("CMAKE_MSVC_RUNTIME_LIBRARY_DEFAULT");
+  if (cmNonempty(msvcRuntimeLibraryDefault)) {
     cmProp msvcRuntimeLibraryValue =
       target->GetProperty("MSVC_RUNTIME_LIBRARY");
     if (!msvcRuntimeLibraryValue) {
@@ -2016,11 +2000,10 @@ void cmLocalGenerator::AddLanguageFlags(std::string& flags,
     std::string const msvcRuntimeLibrary = cmGeneratorExpression::Evaluate(
       *msvcRuntimeLibraryValue, this, config, target);
     if (!msvcRuntimeLibrary.empty()) {
-      if (const char* msvcRuntimeLibraryOptions =
-            this->Makefile->GetDefinition(
-              "CMAKE_" + lang + "_COMPILE_OPTIONS_MSVC_RUNTIME_LIBRARY_" +
-              msvcRuntimeLibrary)) {
-        this->AppendCompileOptions(flags, msvcRuntimeLibraryOptions);
+      if (cmProp msvcRuntimeLibraryOptions = this->Makefile->GetDefinition(
+            "CMAKE_" + lang + "_COMPILE_OPTIONS_MSVC_RUNTIME_LIBRARY_" +
+            msvcRuntimeLibrary)) {
+        this->AppendCompileOptions(flags, *msvcRuntimeLibraryOptions);
       } else if ((this->Makefile->GetSafeDefinition(
                     "CMAKE_" + lang + "_COMPILER_ID") == "MSVC" ||
                   this->Makefile->GetSafeDefinition(
@@ -2046,7 +2029,7 @@ void cmLocalGenerator::AddLanguageFlagsForLinking(
     // when linking in order to use the matching standard library.
     // FIXME: If CMake gains an abstraction for standard library
     // selection, this will have to be reconciled with it.
-    this->AddCompilerRequirementFlag(flags, target, lang);
+    this->AddCompilerRequirementFlag(flags, target, lang, config);
   }
 
   this->AddLanguageFlags(flags, target, lang, config);
@@ -2189,156 +2172,20 @@ void cmLocalGenerator::AddSharedFlags(std::string& flags,
 }
 
 void cmLocalGenerator::AddCompilerRequirementFlag(
-  std::string& flags, cmGeneratorTarget const* target, const std::string& lang)
+  std::string& flags, cmGeneratorTarget const* target, const std::string& lang,
+  const std::string& config)
 {
-  if (lang.empty()) {
-    return;
-  }
-  const char* defaultStd =
-    this->Makefile->GetDefinition("CMAKE_" + lang + "_STANDARD_DEFAULT");
-  if (!defaultStd || !*defaultStd) {
-    // This compiler has no notion of language standard levels.
-    return;
-  }
-  std::string extProp = lang + "_EXTENSIONS";
-  bool ext = true;
-  if (cmProp extPropValue = target->GetProperty(extProp)) {
-    if (cmIsOff(*extPropValue)) {
-      ext = false;
-    }
-  }
-  std::string stdProp = lang + "_STANDARD";
-  cmProp standardProp = target->GetProperty(stdProp);
-  if (!standardProp) {
-    if (ext) {
-      // No language standard is specified and extensions are not disabled.
-      // Check if this compiler needs a flag to enable extensions.
-      std::string const option_flag =
-        "CMAKE_" + lang + "_EXTENSION_COMPILE_OPTION";
-      if (const char* opt =
-            target->Target->GetMakefile()->GetDefinition(option_flag)) {
-        std::vector<std::string> optVec = cmExpandedList(opt);
-        for (std::string const& i : optVec) {
-          this->AppendFlagEscape(flags, i);
-        }
-      }
-    }
-    return;
-  }
-
-  std::string const type = ext ? "EXTENSION" : "STANDARD";
-
-  if (target->GetPropertyAsBool(lang + "_STANDARD_REQUIRED")) {
-    std::string option_flag =
-      "CMAKE_" + lang + *standardProp + "_" + type + "_COMPILE_OPTION";
-
-    const char* opt =
-      target->Target->GetMakefile()->GetDefinition(option_flag);
-    if (!opt) {
-      std::ostringstream e;
-      e << "Target \"" << target->GetName()
-        << "\" requires the language "
-           "dialect \""
-        << lang << *standardProp << "\" "
-        << (ext ? "(with compiler extensions)" : "")
-        << ", but CMake "
-           "does not know the compile flags to use to enable it.";
-      this->IssueMessage(MessageType::FATAL_ERROR, e.str());
-    } else {
-      std::vector<std::string> optVec = cmExpandedList(opt);
-      for (std::string const& i : optVec) {
-        this->AppendFlagEscape(flags, i);
-      }
-    }
-    return;
-  }
-
-  static std::map<std::string, std::vector<std::string>> langStdMap;
-  if (langStdMap.empty()) {
-    // Maintain sorted order, most recent first.
-    langStdMap["CXX"].emplace_back("20");
-    langStdMap["CXX"].emplace_back("17");
-    langStdMap["CXX"].emplace_back("14");
-    langStdMap["CXX"].emplace_back("11");
-    langStdMap["CXX"].emplace_back("98");
-
-    langStdMap["OBJCXX"].emplace_back("20");
-    langStdMap["OBJCXX"].emplace_back("17");
-    langStdMap["OBJCXX"].emplace_back("14");
-    langStdMap["OBJCXX"].emplace_back("11");
-    langStdMap["OBJCXX"].emplace_back("98");
-
-    langStdMap["C"].emplace_back("11");
-    langStdMap["C"].emplace_back("99");
-    langStdMap["C"].emplace_back("90");
-
-    langStdMap["OBJC"].emplace_back("11");
-    langStdMap["OBJC"].emplace_back("99");
-    langStdMap["OBJC"].emplace_back("90");
-
-    langStdMap["CUDA"].emplace_back("20");
-    langStdMap["CUDA"].emplace_back("17");
-    langStdMap["CUDA"].emplace_back("14");
-    langStdMap["CUDA"].emplace_back("11");
-    langStdMap["CUDA"].emplace_back("03");
-  }
-
-  std::string standard(*standardProp);
-  if (lang == "CUDA" && standard == "98") {
-    standard = "03";
-  }
-  std::vector<std::string>& stds = langStdMap[lang];
-
-  auto stdIt = std::find(stds.begin(), stds.end(), standard);
-  if (stdIt == stds.end()) {
-
-    std::string e =
-      lang + "_STANDARD is set to invalid value '" + standard + "'";
-    this->GetGlobalGenerator()->GetCMakeInstance()->IssueMessage(
-      MessageType::FATAL_ERROR, e, target->GetBacktrace());
-    return;
-  }
-
-  auto defaultStdIt = std::find(stds.begin(), stds.end(), defaultStd);
-  if (defaultStdIt == stds.end()) {
-    std::string e = "CMAKE_" + lang +
-      "_STANDARD_DEFAULT is set to invalid value '" + std::string(defaultStd) +
-      "'";
-    this->IssueMessage(MessageType::INTERNAL_ERROR, e);
-    return;
-  }
-
-  // If the standard requested is older than the compiler's default
-  // then we need to use a flag to change it.  The comparison is
-  // greater-or-equal because the standards are stored in backward
-  // chronological order.
-  if (stdIt >= defaultStdIt) {
-    std::string option_flag =
-      "CMAKE_" + lang + *stdIt + "_" + type + "_COMPILE_OPTION";
-
-    std::string const& opt =
-      target->Target->GetMakefile()->GetRequiredDefinition(option_flag);
-    std::vector<std::string> optVec = cmExpandedList(opt);
-    for (std::string const& i : optVec) {
-      this->AppendFlagEscape(flags, i);
-    }
-    return;
-  }
-
-  // The standard requested is at least as new as the compiler's default,
-  // and the standard request is not required.  Decay to the newest standard
-  // for which a flag is defined.
-  for (; stdIt < defaultStdIt; ++stdIt) {
-    std::string option_flag =
-      cmStrCat("CMAKE_", lang, *stdIt, "_", type, "_COMPILE_OPTION");
-
-    if (const char* opt =
-          target->Target->GetMakefile()->GetDefinition(option_flag)) {
-      std::vector<std::string> optVec = cmExpandedList(opt);
+  cmStandardLevelResolver standardResolver(this->Makefile);
+
+  std::string const& optionFlagDef =
+    standardResolver.GetCompileOptionDef(target, lang, config);
+  if (!optionFlagDef.empty()) {
+    cmProp opt = target->Target->GetMakefile()->GetDefinition(optionFlagDef);
+    if (opt) {
+      std::vector<std::string> optVec = cmExpandedList(*opt);
       for (std::string const& i : optVec) {
         this->AppendFlagEscape(flags, i);
       }
-      return;
     }
   }
 }
@@ -2350,7 +2197,7 @@ static void AddVisibilityCompileOption(std::string& flags,
                                        std::string* warnCMP0063)
 {
   std::string compileOption = "CMAKE_" + lang + "_COMPILE_OPTIONS_VISIBILITY";
-  const char* opt = lg->GetMakefile()->GetDefinition(compileOption);
+  cmProp opt = lg->GetMakefile()->GetDefinition(compileOption);
   if (!opt) {
     return;
   }
@@ -2374,7 +2221,7 @@ static void AddVisibilityCompileOption(std::string& flags,
     cmSystemTools::Error(e.str());
     return;
   }
-  std::string option = opt + *prop;
+  std::string option = *opt + *prop;
   lg->AppendFlags(flags, option);
 }
 
@@ -2386,7 +2233,7 @@ static void AddInlineVisibilityCompileOption(std::string& flags,
 {
   std::string compileOption =
     cmStrCat("CMAKE_", lang, "_COMPILE_OPTIONS_VISIBILITY_INLINES_HIDDEN");
-  const char* opt = lg->GetMakefile()->GetDefinition(compileOption);
+  cmProp opt = lg->GetMakefile()->GetDefinition(compileOption);
   if (!opt) {
     return;
   }
@@ -2399,7 +2246,7 @@ static void AddInlineVisibilityCompileOption(std::string& flags,
     *warnCMP0063 += "  VISIBILITY_INLINES_HIDDEN\n";
     return;
   }
-  lg->AppendFlags(flags, opt);
+  lg->AppendFlags(flags, *opt);
 }
 
 void cmLocalGenerator::AddVisibilityPresetFlags(
@@ -2581,13 +2428,58 @@ void cmLocalGenerator::AppendFlagEscape(std::string& flags,
     this->EscapeForShell(rawFlag, false, false, false, this->IsNinjaMulti()));
 }
 
-void cmLocalGenerator::AddPchDependencies(cmGeneratorTarget* target)
+void cmLocalGenerator::AddISPCDependencies(cmGeneratorTarget* target)
 {
-  std::vector<std::string> configsList;
-  std::string configDefault = this->Makefile->GetConfigurations(configsList);
-  if (configsList.empty()) {
-    configsList.push_back(configDefault);
+  std::vector<std::string> enabledLanguages =
+    this->GetState()->GetEnabledLanguages();
+  if (std::find(enabledLanguages.begin(), enabledLanguages.end(), "ISPC") ==
+      enabledLanguages.end()) {
+    return;
+  }
+
+  std::vector<std::string> ispcSuffixes =
+    detail::ComputeISPCObjectSuffixes(target);
+  const bool extra_objects = (ispcSuffixes.size() > 1);
+
+  std::vector<std::string> configsList =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
+  for (std::string const& config : configsList) {
+
+    std::string perConfigDir = target->GetObjectDirectory(config);
+    if (cmProp prop = target->GetProperty("ISPC_HEADER_DIRECTORY")) {
+      perConfigDir = cmSystemTools::CollapseFullPath(
+        cmStrCat(this->GetBinaryDirectory(), '/', *prop));
+    }
+
+    std::vector<cmSourceFile*> sources;
+    target->GetSourceFiles(sources, config);
+
+    // build up the list of ispc headers and extra objects that this target is
+    // generating
+    for (cmSourceFile const* sf : sources) {
+      // Generate this object file's rule file.
+      const std::string& lang = sf->GetLanguage();
+      if (lang == "ISPC") {
+        std::string const& objectName = target->GetObjectName(sf);
+        std::string ispcSource =
+          cmSystemTools::GetFilenameWithoutLastExtension(objectName);
+
+        auto headerPath = cmStrCat(perConfigDir, '/', ispcSource, ".h");
+        target->AddISPCGeneratedHeader(headerPath, config);
+        if (extra_objects) {
+          std::vector<std::string> objs = detail::ComputeISPCExtraObjects(
+            objectName, perConfigDir, ispcSuffixes);
+          target->AddISPCGeneratedObject(std::move(objs), config);
+        }
+      }
+    }
   }
+}
+
+void cmLocalGenerator::AddPchDependencies(cmGeneratorTarget* target)
+{
+  std::vector<std::string> configsList =
+    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);
 
   for (std::string const& config : configsList) {
     // FIXME: Refactor collection of sources to not evaluate object
@@ -2682,17 +2574,29 @@ void cmLocalGenerator::AddPchDependencies(cmGeneratorTarget* target)
                   this->Makefile->GetSafeDefinition(
                     cmStrCat("CMAKE_", lang, "_FLAGS_", configUpper));
 
+                bool editAndContinueDebugInfo =
+                  langFlags.find("/ZI") != std::string::npos ||
+                  langFlags.find("-ZI") != std::string::npos;
+
+                bool enableDebuggingInformation =
+                  langFlags.find("/Zi") != std::string::npos ||
+                  langFlags.find("-Zi") != std::string::npos;
+
                 // MSVC 2008 is producing both .pdb and .idb files with /Zi.
-                if ((langFlags.find("/ZI") != std::string::npos ||
-                     langFlags.find("-ZI") != std::string::npos) ||
-                    (cmSystemTools::VersionCompare(cmSystemTools::OP_LESS,
-                                                   compilerVersion.c_str(),
-                                                   "16.0") &&
-                     compilerId == "MSVC")) {
+                bool msvc2008OrLess =
+                  cmSystemTools::VersionCompare(
+                    cmSystemTools::OP_LESS, compilerVersion.c_str(), "16.0") &&
+                  compilerId == "MSVC";
+                // but not when used via toolset -Tv90
+                if (this->Makefile->GetSafeDefinition(
+                      "CMAKE_VS_PLATFORM_TOOLSET") == "v90") {
+                  msvc2008OrLess = false;
+                }
+
+                if (editAndContinueDebugInfo || msvc2008OrLess) {
                   CopyPchCompilePdb(config, target, *ReuseFrom, reuseTarget,
                                     { ".pdb", ".idb" });
-                } else if ((langFlags.find("/Zi") != std::string::npos ||
-                            langFlags.find("-Zi") != std::string::npos)) {
+                } else if (enableDebuggingInformation) {
                   CopyPchCompilePdb(config, target, *ReuseFrom, reuseTarget,
                                     { ".pdb" });
                 }
@@ -3043,12 +2947,12 @@ void cmLocalGenerator::AppendIPOLinkerFlags(std::string& flags,
   }
 
   const std::string name = "CMAKE_" + lang + "_LINK_OPTIONS_IPO";
-  const char* rawFlagsList = this->Makefile->GetDefinition(name);
+  cmProp rawFlagsList = this->Makefile->GetDefinition(name);
   if (rawFlagsList == nullptr) {
     return;
   }
 
-  std::vector<std::string> flagsList = cmExpandedList(rawFlagsList);
+  std::vector<std::string> flagsList = cmExpandedList(*rawFlagsList);
   for (std::string const& o : flagsList) {
     this->AppendFlagEscape(flags, o);
   }
@@ -3234,10 +3138,10 @@ void cmLocalGenerator::JoinDefines(const std::set<std::string>& defines,
   // Lookup the define flag for the current language.
   std::string dflag = "-D";
   if (!lang.empty()) {
-    const char* df =
+    cmProp df =
       this->Makefile->GetDefinition(cmStrCat("CMAKE_", lang, "_DEFINE_FLAG"));
-    if (df && *df) {
-      dflag = df;
+    if (cmNonempty(df)) {
+      dflag = *df;
     }
   }
   const char* itemSeparator = definesString.empty() ? "" : " ";
@@ -3281,18 +3185,18 @@ void cmLocalGenerator::AppendFeatureOptions(std::string& flags,
                                             const std::string& lang,
                                             const char* feature)
 {
-  const char* optionList = this->Makefile->GetDefinition(
+  cmProp optionList = this->Makefile->GetDefinition(
     cmStrCat("CMAKE_", lang, "_COMPILE_OPTIONS_", feature));
   if (optionList != nullptr) {
-    std::vector<std::string> options = cmExpandedList(optionList);
+    std::vector<std::string> options = cmExpandedList(*optionList);
     for (std::string const& o : options) {
       this->AppendFlagEscape(flags, o);
     }
   }
 }
 
-const char* cmLocalGenerator::GetFeature(const std::string& feature,
-                                         const std::string& config)
+cmProp cmLocalGenerator::GetFeature(const std::string& feature,
+                                    const std::string& config)
 {
   std::string featureName = feature;
   // TODO: Define accumulation policy for features (prepend, append,
@@ -3304,7 +3208,7 @@ const char* cmLocalGenerator::GetFeature(const std::string& feature,
   cmStateSnapshot snp = this->StateSnapshot;
   while (snp.IsValid()) {
     if (cmProp value = snp.GetDirectory().GetProperty(featureName)) {
-      return value->c_str();
+      return value;
     }
     snp = snp.GetBuildsystemDirectoryParent();
   }
@@ -3739,9 +3643,9 @@ KWIML_INT_uint64_t cmLocalGenerator::GetBackwardsCompatibility()
     unsigned int major = 0;
     unsigned int minor = 0;
     unsigned int patch = 0;
-    if (const char* value =
+    if (cmProp value =
           this->Makefile->GetDefinition("CMAKE_BACKWARDS_COMPATIBILITY")) {
-      switch (sscanf(value, "%u.%u.%u", &major, &minor, &patch)) {
+      switch (sscanf(value->c_str(), "%u.%u.%u", &major, &minor, &patch)) {
         case 2:
           patch = 0;
           break;
@@ -3845,8 +3749,7 @@ void cmLocalGenerator::GenerateAppleInfoPList(cmGeneratorTarget* target,
 {
   // Find the Info.plist template.
   cmProp in = target->GetProperty("MACOSX_BUNDLE_INFO_PLIST");
-  std::string inFile =
-    (in && !in->empty()) ? *in : "MacOSXBundleInfo.plist.in";
+  std::string inFile = cmNonempty(in) ? *in : "MacOSXBundleInfo.plist.in";
   if (!cmSystemTools::FileIsFullPath(inFile)) {
     std::string inMod = this->Makefile->GetModulesFile(inFile);
     if (!inMod.empty()) {
@@ -3876,7 +3779,7 @@ void cmLocalGenerator::GenerateAppleInfoPList(cmGeneratorTarget* target,
   cmLGInfoProp(mf, target, "MACOSX_BUNDLE_SHORT_VERSION_STRING");
   cmLGInfoProp(mf, target, "MACOSX_BUNDLE_BUNDLE_VERSION");
   cmLGInfoProp(mf, target, "MACOSX_BUNDLE_COPYRIGHT");
-  mf->ConfigureFile(inFile, fname, false, false, false);
+  mf->ConfigureFile(inFile, fname, false, false, false, true);
 }
 
 void cmLocalGenerator::GenerateFrameworkInfoPList(
@@ -3885,8 +3788,7 @@ void cmLocalGenerator::GenerateFrameworkInfoPList(
 {
   // Find the Info.plist template.
   cmProp in = target->GetProperty("MACOSX_FRAMEWORK_INFO_PLIST");
-  std::string inFile =
-    (in && !in->empty()) ? *in : "MacOSXFrameworkInfo.plist.in";
+  std::string inFile = cmNonempty(in) ? *in : "MacOSXFrameworkInfo.plist.in";
   if (!cmSystemTools::FileIsFullPath(inFile)) {
     std::string inMod = this->Makefile->GetModulesFile(inFile);
     if (!inMod.empty()) {
@@ -3912,7 +3814,7 @@ void cmLocalGenerator::GenerateFrameworkInfoPList(
   cmLGInfoProp(mf, target, "MACOSX_FRAMEWORK_IDENTIFIER");
   cmLGInfoProp(mf, target, "MACOSX_FRAMEWORK_SHORT_VERSION_STRING");
   cmLGInfoProp(mf, target, "MACOSX_FRAMEWORK_BUNDLE_VERSION");
-  mf->ConfigureFile(inFile, fname, false, false, false);
+  mf->ConfigureFile(inFile, fname, false, false, false, true);
 }
 
 namespace {
@@ -4156,4 +4058,44 @@ void AddUtilityCommand(cmLocalGenerator& lg, const cmListFileBacktrace& lfbt,
     target->AddSource(force.NameCMP0049);
   }
 }
+
+std::vector<std::string> ComputeISPCObjectSuffixes(cmGeneratorTarget* target)
+{
+  const std::string& targetProperty =
+    target->GetSafeProperty("ISPC_INSTRUCTION_SETS");
+  std::vector<std::string> ispcTargets;
+
+  if (!cmIsOff(targetProperty)) {
+    cmExpandList(targetProperty, ispcTargets);
+    for (auto& ispcTarget : ispcTargets) {
+      // transform targets into the suffixes
+      auto pos = ispcTarget.find('-');
+      auto target_suffix = ispcTarget.substr(0, pos);
+      if (target_suffix ==
+          "avx1") { // when targetting avx1 ISPC uses the 'avx' output string
+        target_suffix = "avx";
+      }
+      ispcTarget = target_suffix;
+    }
+  }
+  return ispcTargets;
+}
+
+std::vector<std::string> ComputeISPCExtraObjects(
+  std::string const& objectName, std::string const& buildDirectory,
+  std::vector<std::string> const& ispcSuffixes)
+{
+  std::vector<std::string> computedObjects;
+  computedObjects.reserve(ispcSuffixes.size());
+
+  auto extension = cmSystemTools::GetFilenameLastExtension(objectName);
+  auto objNameNoExt =
+    cmSystemTools::GetFilenameWithoutLastExtension(objectName);
+  for (const auto& ispcTarget : ispcSuffixes) {
+    computedObjects.emplace_back(
+      cmStrCat(buildDirectory, "/", objNameNoExt, "_", ispcTarget, extension));
+  }
+
+  return computedObjects;
+}
 }
diff --git a/Source/cmLocalGenerator.h b/Source/cmLocalGenerator.h
index f2d9145..fad6136 100644
--- a/Source/cmLocalGenerator.h
+++ b/Source/cmLocalGenerator.h
@@ -1,7 +1,6 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLocalGenerator_h
-#define cmLocalGenerator_h
+#pragma once
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
@@ -20,6 +19,7 @@
 #include "cmMessageType.h"
 #include "cmOutputConverter.h"
 #include "cmPolicies.h"
+#include "cmProperty.h"
 #include "cmStateSnapshot.h"
 
 class cmComputeLinkInformation;
@@ -123,7 +123,8 @@ public:
                               const std::string& config);
   void AddCompilerRequirementFlag(std::string& flags,
                                   cmGeneratorTarget const* target,
-                                  const std::string& lang);
+                                  const std::string& lang,
+                                  const std::string& config);
   //! Append flags to a string.
   virtual void AppendFlags(std::string& flags,
                            const std::string& newFlags) const;
@@ -131,6 +132,7 @@ public:
                            const std::vector<BT<std::string>>& newFlags) const;
   virtual void AppendFlagEscape(std::string& flags,
                                 const std::string& rawFlag) const;
+  void AddISPCDependencies(cmGeneratorTarget* target);
   void AddPchDependencies(cmGeneratorTarget* target);
   void AddUnityBuild(cmGeneratorTarget* target);
   void AppendIPOLinkerFlags(std::string& flags, cmGeneratorTarget* target,
@@ -208,8 +210,7 @@ public:
   void AppendFeatureOptions(std::string& flags, const std::string& lang,
                             const char* feature);
 
-  const char* GetFeature(const std::string& feature,
-                         const std::string& config);
+  cmProp GetFeature(const std::string& feature, const std::string& config);
 
   /** \brief Get absolute path to dependency \a name
    *
@@ -593,6 +594,9 @@ void AddUtilityCommand(cmLocalGenerator& lg, const cmListFileBacktrace& lfbt,
                        bool escapeOldStyle, const char* comment,
                        bool uses_terminal, bool command_expand_lists,
                        const std::string& job_pool, bool stdPipesUTF8);
-}
 
-#endif
+std::vector<std::string> ComputeISPCObjectSuffixes(cmGeneratorTarget* target);
+std::vector<std::string> ComputeISPCExtraObjects(
+  std::string const& objectName, std::string const& buildDirectory,
+  std::vector<std::string> const& ispcSuffixes);
+}
diff --git a/Source/cmLocalGhsMultiGenerator.cxx b/Source/cmLocalGhsMultiGenerator.cxx
index 098fa5a..b223813 100644
--- a/Source/cmLocalGhsMultiGenerator.cxx
+++ b/Source/cmLocalGhsMultiGenerator.cxx
@@ -2,16 +2,13 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmLocalGhsMultiGenerator.h"
 
-#include <algorithm>
 #include <utility>
-
-#include <cmext/algorithm>
+#include <vector>
 
 #include "cmGeneratorTarget.h"
 #include "cmGhsMultiTargetGenerator.h"
 #include "cmGlobalGenerator.h"
 #include "cmSourceFile.h"
-#include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 
@@ -30,34 +27,16 @@ std::string cmLocalGhsMultiGenerator::GetTargetDirectory(
   return dir;
 }
 
-void cmLocalGhsMultiGenerator::GenerateTargetsDepthFirst(
-  cmGeneratorTarget* target, std::vector<cmGeneratorTarget*>& remaining)
-{
-  if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
-    return;
-  }
-  // Find this target in the list of remaining targets.
-  auto it = std::find(remaining.begin(), remaining.end(), target);
-  if (it == remaining.end()) {
-    // This target was already handled.
-    return;
-  }
-  // Remove this target from the list of remaining targets because
-  // we are handling it now.
-  *it = nullptr;
-
-  cmGhsMultiTargetGenerator tg(target);
-  tg.Generate();
-}
-
 void cmLocalGhsMultiGenerator::Generate()
 {
-  std::vector<cmGeneratorTarget*> remaining;
-  cm::append(remaining, this->GetGeneratorTargets());
-  for (auto& t : remaining) {
-    if (t) {
-      this->GenerateTargetsDepthFirst(t, remaining);
+  for (cmGeneratorTarget* gt :
+       this->GlobalGenerator->GetLocalGeneratorTargetsInOrder(this)) {
+    if (!gt->IsInBuildSystem()) {
+      continue;
     }
+
+    cmGhsMultiTargetGenerator tg(gt);
+    tg.Generate();
   }
 }
 
diff --git a/Source/cmLocalGhsMultiGenerator.h b/Source/cmLocalGhsMultiGenerator.h
index 2250e57..be32a94 100644
--- a/Source/cmLocalGhsMultiGenerator.h
+++ b/Source/cmLocalGhsMultiGenerator.h
@@ -1,11 +1,9 @@
 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
    file Copyright.txt or https://cmake.org/licensing for details.  */
-#ifndef cmLocalGhsMultiGenerator_h
-#define cmLocalGhsMultiGenerator_h
+#pragma once
 
 #include <map>
 #include <string>
-#include <vector>
 
 #include "cmLocalGenerator.h"
 
@@ -38,10 +36,4 @@ public:
   void ComputeObjectFilenames(
     std::map<cmSourceFile const*, std::string>& mapping,
     cmGeneratorTarget const* gt = nullptr) override;
-
-private:
-  void GenerateTargetsDepthFirst(cmGeneratorTarget* target,
-                                 std::vector<cmGeneratorTarget*>& remaining);
 };
-
-#endif
diff --git a/Source/cmLocalNinjaGenerator.cxx b/Source/cmLocalNinjaGenerator.cxx
index 87e8aa4..ad782ee 100644
--- a/Source/cmLocalNinjaGenerator.cxx
+++ b/Source/cmLocalNinjaGenerator.cxx
@@ -84,13 +84,31 @@ void cmLocalNinjaGenerator::Generate()
     if (!showIncludesPrefix.empty()) {
       cmGlobalNinjaGenerator::WriteComment(this->GetRulesFileStream(),
                                            "localized /showIncludes string");
-      this->GetRulesFileStream()
-        << "msvc_deps_prefix = " << showIncludesPrefix << "\n\n";
+      this->GetRulesFileStream() << "msvc_deps_prefix = ";
+#ifdef WIN32
+      // Ninja uses the ANSI Windows APIs, so strings in the rules file
+      // typically need to be ANSI encoded. However, in this case the compiler
+      // is being invoked using the UTF-8 codepage so the /showIncludes prefix
+      // will be UTF-8 encoded on stdout. Ninja can't successfully compare this
+      // UTF-8 encoded prefix to the ANSI encoded msvc_deps_prefix if it
+      // contains any non-ASCII characters and dependency checking will fail.
+      // As a workaround, leave the msvc_deps_prefix UTF-8 encoded even though
+      // the rest of the file is ANSI encoded.
+      if (GetConsoleOutputCP() == CP_UTF8 && GetACP() != CP_UTF8) {
+        this->GetRulesFileStream().WriteRaw(showIncludesPrefix);
+      } else {
+        this->GetRulesFileStream() << showIncludesPrefix;
+      }
+#else
+      // It's safe to use the standard encoding on other platforms.
+      this->GetRulesFileStream() << showIncludesPrefix;
+#endif
+      this->GetRulesFileStream() << "\n\n";
     }
   }
 
   for (const auto& target : this->GetGeneratorTargets()) {
-    if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
+    if (!target->IsInBuildSystem()) {
       continue;
     }
     auto tg = cmNinjaTargetGenerator::New(target.get());
@@ -102,9 +120,10 @@ void cmLocalNinjaGenerator::Generate()
               this->GetGlobalGenerator()->IsMultiConfig()) {
             cmNinjaBuild phonyAlias("phony");
             this->GetGlobalNinjaGenerator()->AppendTargetOutputs(
-              target.get(), phonyAlias.Outputs, "");
+              target.get(), phonyAlias.Outputs, "", DependOnTargetArtifact);
             this->GetGlobalNinjaGenerator()->AppendTargetOutputs(
-              target.get(), phonyAlias.ExplicitDeps, config);
+              target.get(), phonyAlias.ExplicitDeps, config,
+              DependOnTargetArtifact);
             this->GetGlobalNinjaGenerator()->WriteBuild(
               *this->GetGlobalNinjaGenerator()->GetConfigFileStream(config),
               phonyAlias);
@@ -115,11 +134,12 @@ void cmLocalNinjaGenerator::Generate()
           if (!this->GetGlobalNinjaGenerator()->GetDefaultConfigs().empty()) {
             cmNinjaBuild phonyAlias("phony");
             this->GetGlobalNinjaGenerator()->AppendTargetOutputs(
-              target.get(), phonyAlias.Outputs, "");
+              target.get(), phonyAlias.Outputs, "", DependOnTargetArtifact);
             for (auto const& config :
                  this->GetGlobalNinjaGenerator()->GetDefaultConfigs()) {
               this->GetGlobalNinjaGenerator()->AppendTargetOutputs(
-                target.get(), phonyAlias.ExplicitDeps, config);
+                target.get(), phonyAlias.ExplicitDeps, config,
+                DependOnTargetArtifact);
             }
             this->GetGlobalNinjaGenerator()->WriteBuild(
               *this->GetGlobalNinjaGenerator()->GetDefaultFileStream(),
@@ -127,10 +147,11 @@ void cmLocalNinjaGenerator::Generate()
           }
           cmNinjaBuild phonyAlias("phony");
           this->GetGlobalNinjaGenerator()->AppendTargetOutputs(
-            target.get(), phonyAlias.Outputs, "all");
+            target.get(), phonyAlias.Outputs, "all", DependOnTargetArtifact);
           for (auto const& config : this->GetConfigNames()) {
             this->GetGlobalNinjaGenerator()->AppendTargetOutputs(
-              target.get(), phonyAlias.ExplicitDeps, config);
+              target.get(), phonyAlias.ExplicitDeps, config,
+              DependOnTargetArtifact);
           }
           this->GetGlobalNinjaGenerator()->WriteBuild(
             *this->GetGlobalNinjaGenerator()->GetDefaultFileStream(),
@@ -291,7 +312,7 @@ void cmLocalNinjaGenerator::WritePools(std::ostream& os)
   cmProp jobpools =
     this->GetCMakeInstance()->GetState()->GetGlobalProperty("JOB_POOLS");
   if (!jobpools) {
-    jobpools = this->GetMakefile()->GetDef("CMAKE_JOB_POOLS");
+    jobpools = this->GetMakefile()->GetDefinition("CMAKE_JOB_POOLS");
   }
   if (jobpools) {
     cmGlobalNinjaGenerator::WriteComment(
@@ -342,7 +363,7 @@ void cmLocalNinjaGenerator::WriteProcessedMakefile(std::ostream& os)
 {
   cmGlobalNinjaGenerator::WriteDivider(os);
   os << "# Write statements declared in CMakeLists.txt:\n"
-     << "# " << this->Makefile->GetDefinition("CMAKE_CURRENT_LIST_FILE")
+     << "# " << this->Makefile->GetSafeDefinition("CMAKE_CURRENT_LIST_FILE")
      << '\n';
   if (this->IsRootMakefile()) {
     os << "# Which is the root file.\n";
@@ -355,8 +376,8 @@ void cmLocalNinjaGenerator::AppendTargetOutputs(cmGeneratorTarget* target,
                                                 cmNinjaDeps& outputs,
                                                 const std::string& config)
 {
-  this->GetGlobalNinjaGenerator()->AppendTargetOutputs(target, outputs,
-                                                       config);
+  this->GetGlobalNinjaGenerator()->AppendTargetOutputs(target, outputs, config,
+                                                       DependOnTargetArtifact);
 }
 
 void cmLocalNinjaGenerator::AppendTargetDepends(cmGeneratorTarget* target,
@@ -668,7 +689,7 @@ std::string cmLocalNinjaGenerator::MakeCustomLauncher(
 {
   cmProp property_value = this->Makefile->GetProperty("RULE_LAUNCH_CUSTOM");
 
-  if (!property_value || property_value->empty()) {
+  if (!cmNonempty(property_value)) {
     return std::string();
   }
 
diff --git a/Source/cmLocalNinjaGenerator.h b/Source/cmLocalNinjaGenerator.h
index ef160e7..e81402c 100644
--- a/Source/cmLocalNinjaGenerator.h
+++ b/Source/cmLocalNinjaGenerator.h