Upstream macCatalyst driver

clang/include/clang/Basic/DiagnosticDriverKinds.td

@@ -206,6 +206,8 @@ def warn_invalid_ios_deployment_target : Warning<
   "invalid iOS deployment version '%0', iOS 10 is the maximum deployment "
   "target for 32-bit targets">, InGroup<InvalidIOSDeploymentTarget>,
   DefaultError;
+def err_invalid_macos_32bit_deployment_target : Error<
+  "32-bit targets are not supported when building for Mac Catalyst">;
 def err_drv_conflicting_deployment_targets : Error<
   "conflicting deployment targets, both '%0' and '%1' are present in environment">;
 def err_arc_unsupported_on_runtime : Error<

clang/include/clang/Driver/DarwinSDKInfo.h

@@ -10,6 +10,7 @@
 #define LLVM_CLANG_DRIVER_DARWIN_SDK_INFO_H
 
 #include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringMap.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/VersionTuple.h"
 #include "llvm/Support/VirtualFileSystem.h"
@@ -20,12 +21,26 @@ namespace driver {
 /// The information about the darwin SDK that was used during this compilation.
 class DarwinSDKInfo {
 public:
+  /// Represents the mapping between macOS and IosMac versions.
+  class IOSMacVersionMapping {
+  public:
+    VersionTuple getiOSMacVersionForMacOSVersion();
+
+    llvm::StringMap<VersionTuple> MacOS2iOSMacMapping;
+    llvm::StringMap<VersionTuple> IosMac2macOSMapping;
+  };
+
   DarwinSDKInfo(llvm::VersionTuple Version) : Version(Version) {}
 
   const llvm::VersionTuple &getVersion() const { return Version; }
 
+  IOSMacVersionMapping &getVersionMap() { return VersionMap; }
+
+  const IOSMacVersionMapping &getVersionMap() const { return VersionMap; }
+
 private:
   llvm::VersionTuple Version;
+  IOSMacVersionMapping VersionMap;
 };
 
 /// Parse the SDK information from the SDKSettings.json file.

clang/lib/Driver/DarwinSDKInfo.cpp

@@ -15,6 +15,42 @@
 using namespace clang::driver;
 using namespace clang;
 
+static Optional<DarwinSDKInfo>
+parseDarwinSDKSettingsJSON(const llvm::json::Object *Obj) {
+  auto VersionString = Obj->getString("Version");
+  if (!VersionString)
+    return None;
+  VersionTuple Version;
+  if (Version.tryParse(*VersionString))
+    return None;
+  DarwinSDKInfo SDKInfo(Version);
+  if (const auto *VM = Obj->getObject("VersionMap")) {
+    auto parseVersionMap = [](const llvm::json::Object &Obj,
+                              llvm::StringMap<VersionTuple> &Mapping) -> bool {
+      for (const auto &KV : Obj) {
+        if (auto Val = KV.getSecond().getAsString()) {
+          llvm::VersionTuple Version;
+          if (Version.tryParse(*Val))
+            return true;
+          Mapping[KV.getFirst()] = Version;
+        }
+      }
+      return false;
+    };
+    if (const auto *Mapping = VM->getObject("macOS_iOSMac")) {
+      if (parseVersionMap(*Mapping,
+                          SDKInfo.getVersionMap().MacOS2iOSMacMapping))
+        return None;
+    }
+    if (const auto *Mapping = VM->getObject("iOSMac_macOS")) {
+      if (parseVersionMap(*Mapping,
+                          SDKInfo.getVersionMap().IosMac2macOSMapping))
+        return None;
+    }
+  }
+  return std::move(SDKInfo);
+}
+
 Expected<Optional<DarwinSDKInfo>>
 driver::parseDarwinSDKInfo(llvm::vfs::FileSystem &VFS, StringRef SDKRootPath) {
   llvm::SmallString<256> Filepath = SDKRootPath;
@@ -31,12 +67,8 @@ driver::parseDarwinSDKInfo(llvm::vfs::FileSystem &VFS, StringRef SDKRootPath) {
     return Result.takeError();
 
   if (const auto *Obj = Result->getAsObject()) {
-    auto VersionString = Obj->getString("Version");
-    if (VersionString) {
-      VersionTuple Version;
-      if (!Version.tryParse(*VersionString))
-        return DarwinSDKInfo(Version);
-    }
+    if (auto SDKInfo = parseDarwinSDKSettingsJSON(Obj))
+      return std::move(SDKInfo);
   }
   return llvm::make_error<llvm::StringError>("invalid SDKSettings.json",
                                              llvm::inconvertibleErrorCode());