Xcode: Obey SYSTEM keyword for includes (#15687)

CMake used to put all header search paths into HEADER_SEARCH_PATHS
attribute. Unfortunately this attribute does not support to declare
a search path as a system include.

As a hack one could add a -isystem /path to the cflags but then include
ordering is not deterministic. A better approach was chosen with this
patch by not filling HEADER_SEARCH_PATHS at all and to populate
the C, C++, and Fortran flags directly. The include paths used by
Xcode should be now identical to the ones used by Unix Makefiles and
Ninja generator.

1 files changed, 34 insertions, 14 deletions

diff --git a/Source/cmGlobalXCodeGenerator.cxx b/Source/cmGlobalXCodeGenerator.cxx
index b396ea1..780ca90 100644
--- a/Source/cmGlobalXCodeGenerator.cxx
+++ b/Source/cmGlobalXCodeGenerator.cxx
@@ -1907,23 +1907,40 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmGeneratorTarget* gtgt,
 
   BuildObjectListOrString dirs(this, this->XcodeVersion >= 30);
   BuildObjectListOrString fdirs(this, this->XcodeVersion >= 30);
-  std::vector<std::string> includes;
-  this->CurrentLocalGenerator->GetIncludeDirectories(includes, gtgt, "C",
-                                                     configName);
   std::set<std::string> emitted;
   emitted.insert("/System/Library/Frameworks");
-  for (std::vector<std::string>::iterator i = includes.begin();
-       i != includes.end(); ++i) {
-    if (this->NameResolvesToFramework(i->c_str())) {
-      std::string frameworkDir = *i;
-      frameworkDir += "/../";
-      frameworkDir = cmSystemTools::CollapseFullPath(frameworkDir);
-      if (emitted.insert(frameworkDir).second) {
-        fdirs.Add(this->XCodeEscapePath(frameworkDir));
+
+  if (this->XcodeVersion < 60) {
+    std::vector<std::string> includes;
+    this->CurrentLocalGenerator->GetIncludeDirectories(includes, gtgt, "C",
+                                                       configName);
+    for (std::vector<std::string>::iterator i = includes.begin();
+         i != includes.end(); ++i) {
+      if (this->NameResolvesToFramework(i->c_str())) {
+        std::string frameworkDir = *i;
+        frameworkDir += "/../";
+        frameworkDir = cmSystemTools::CollapseFullPath(frameworkDir);
+        if (emitted.insert(frameworkDir).second) {
+          fdirs.Add(this->XCodeEscapePath(frameworkDir));
+        }
+      } else {
+        std::string incpath = this->XCodeEscapePath(*i);
+        dirs.Add(incpath);
+      }
+    }
+  } else {
+    for (std::set<std::string>::iterator li = languages.begin();
+         li != languages.end(); ++li) {
+      std::vector<std::string> includes;
+      this->CurrentLocalGenerator->GetIncludeDirectories(includes, gtgt, *li,
+                                                         configName);
+      std::string includeFlags = this->CurrentLocalGenerator->GetIncludeFlags(
+        includes, gtgt, *li, true, false, configName);
+
+      std::string& flags = cflags[*li];
+      if (!includeFlags.empty()) {
+        flags += " " + includeFlags;
       }
-    } else {
-      std::string incpath = this->XCodeEscapePath(*i);
-      dirs.Add(incpath);
     }
   }
   // Add framework search paths needed for linking.
@@ -2008,6 +2025,9 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmGeneratorTarget* gtgt,
                                   this->CreateString(flags));
     } else if (*li == "C") {
       buildSettings->AddAttribute("OTHER_CFLAGS", this->CreateString(flags));
+    } else if (*li == "Swift") {
+      buildSettings->AddAttribute("OTHER_SWIFT_FLAGS",
+                                  this->CreateString(flags));
     }
   }