Darwin: Emit deployment target that matches the SDK

Closes: #17431

4 files changed, 61 insertions, 10 deletions

diff --git a/Source/cmGlobalXCodeGenerator.cxx b/Source/cmGlobalXCodeGenerator.cxx
index f392589..5c6a846 100644
--- a/Source/cmGlobalXCodeGenerator.cxx
+++ b/Source/cmGlobalXCodeGenerator.cxx
@@ -2992,7 +2992,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeObjects(
     buildSettings->AddAttribute("ARCHS", this->CreateString(archs));
   }
   if (deploymentTarget && *deploymentTarget) {
-    buildSettings->AddAttribute("MACOSX_DEPLOYMENT_TARGET",
+    buildSettings->AddAttribute(GetDeploymentPlatform(root->GetMakefile()),
                                 this->CreateString(deploymentTarget));
   }
   if (!this->GeneratorToolset.empty()) {
@@ -3627,3 +3627,24 @@ void cmGlobalXCodeGenerator::ComputeTargetObjectDirectory(
   dir += "/";
   gt->ObjectDirectory = dir;
 }
+
+std::string cmGlobalXCodeGenerator::GetDeploymentPlatform(const cmMakefile* mf)
+{
+  switch (mf->GetAppleSDKType()) {
+    case cmMakefile::AppleSDK::AppleTVOS:
+    case cmMakefile::AppleSDK::AppleTVSimulator:
+      return "TVOS_DEPLOYMENT_TARGET";
+
+    case cmMakefile::AppleSDK::IPhoneOS:
+    case cmMakefile::AppleSDK::IPhoneSimulator:
+      return "IPHONEOS_DEPLOYMENT_TARGET";
+
+    case cmMakefile::AppleSDK::WatchOS:
+    case cmMakefile::AppleSDK::WatchSimulator:
+      return "WATCHOS_DEPLOYMENT_TARGET";
+
+    case cmMakefile::AppleSDK::MacOS:
+    default:
+      return "MACOSX_DEPLOYMENT_TARGET";
+  }
+}
diff --git a/Source/cmGlobalXCodeGenerator.h b/Source/cmGlobalXCodeGenerator.h
index b758e97..2269b25 100644
--- a/Source/cmGlobalXCodeGenerator.h
+++ b/Source/cmGlobalXCodeGenerator.h
@@ -254,6 +254,8 @@ private:
                                         const std::string& configName,
                                         const cmGeneratorTarget* t) const;
 
+  static std::string GetDeploymentPlatform(const cmMakefile* mf);
+
   void ComputeArchitectures(cmMakefile* mf);
   void ComputeObjectDirArch(cmMakefile* mf);
 
diff --git a/Source/cmMakefile.cxx b/Source/cmMakefile.cxx
index c70a7ae..5d6029c 100644
--- a/Source/cmMakefile.cxx
+++ b/Source/cmMakefile.cxx
@@ -2244,25 +2244,38 @@ bool cmMakefile::PlatformIsx32() const
   return false;
 }
 
-bool cmMakefile::PlatformIsAppleEmbedded() const
+cmMakefile::AppleSDK cmMakefile::GetAppleSDKType() const
 {
   std::string sdkRoot;
   sdkRoot = this->GetSafeDefinition("CMAKE_OSX_SYSROOT");
   sdkRoot = cmSystemTools::LowerCase(sdkRoot);
 
-  const std::string embedded[] = {
-    "appletvos",       "appletvsimulator", "iphoneos",
-    "iphonesimulator", "watchos",          "watchsimulator",
+  struct
+  {
+    std::string name;
+    AppleSDK sdk;
+  } const sdkDatabase[]{
+    { "appletvos", AppleSDK::AppleTVOS },
+    { "appletvsimulator", AppleSDK::AppleTVSimulator },
+    { "iphoneos", AppleSDK::IPhoneOS },
+    { "iphonesimulator", AppleSDK::IPhoneSimulator },
+    { "watchos", AppleSDK::WatchOS },
+    { "watchsimulator", AppleSDK::WatchSimulator },
   };
 
-  for (std::string const& i : embedded) {
-    if (sdkRoot.find(i) == 0 ||
-        sdkRoot.find(std::string("/") + i) != std::string::npos) {
-      return true;
+  for (auto entry : sdkDatabase) {
+    if (sdkRoot.find(entry.name) == 0 ||
+        sdkRoot.find(std::string("/") + entry.name) != std::string::npos) {
+      return entry.sdk;
     }
   }
 
-  return false;
+  return AppleSDK::MacOS;
+}
+
+bool cmMakefile::PlatformIsAppleEmbedded() const
+{
+  return GetAppleSDKType() != AppleSDK::MacOS;
 }
 
 const char* cmMakefile::GetSONameFlag(const std::string& language) const
diff --git a/Source/cmMakefile.h b/Source/cmMakefile.h
index e1ec8ed..40e8148 100644
--- a/Source/cmMakefile.h
+++ b/Source/cmMakefile.h
@@ -439,6 +439,21 @@ public:
   /** Return whether the target platform is x32.  */
   bool PlatformIsx32() const;
 
+  /** Apple SDK Type */
+  enum class AppleSDK
+  {
+    MacOS,
+    IPhoneOS,
+    IPhoneSimulator,
+    AppleTVOS,
+    AppleTVSimulator,
+    WatchOS,
+    WatchSimulator,
+  };
+
+  /** What SDK type points CMAKE_OSX_SYSROOT to? */
+  AppleSDK GetAppleSDKType() const;
+
   /** Return whether the target platform is Apple iOS.  */
   bool PlatformIsAppleEmbedded() const;