3 files changed, 19 insertions, 13 deletions

diff --git a/lib/Lex/HeaderSearch.cpp b/lib/Lex/HeaderSearch.cpp
index 6c5c64b..b805990 100644
--- a/lib/Lex/HeaderSearch.cpp
+++ b/lib/Lex/HeaderSearch.cpp
@@ -995,7 +995,8 @@ HeaderFileInfo &HeaderSearch::getFileInfo(const FileEntry *FE) {
   return HFI;
 }
 
-bool HeaderSearch::tryGetFileInfo(const FileEntry *FE, HeaderFileInfo &Result) const {
+bool HeaderSearch::tryGetFileInfo(const FileEntry *FE,
+                                  HeaderFileInfo &Result) const {
   if (FE->getUID() >= FileInfo.size())
     return false;
   const HeaderFileInfo &HFI = FileInfo[FE->getUID()];
@@ -1028,7 +1029,7 @@ void HeaderSearch::MarkFileModuleHeader(const FileEntry *FE,
 
   HeaderFileInfo &HFI = FileInfo[FE->getUID()];
   HFI.isModuleHeader = true;
-  HFI.isCompilingModuleHeader = isCompilingModuleHeader;
+  HFI.isCompilingModuleHeader |= isCompilingModuleHeader;
   HFI.setHeaderRole(Role);
 }
 
@@ -1058,15 +1059,16 @@ bool HeaderSearch::ShouldEnterIncludeFile(Preprocessor &PP,
   // Next, check to see if the file is wrapped with #ifndef guards.  If so, and
   // if the macro that guards it is defined, we know the #include has no effect.
   if (const IdentifierInfo *ControllingMacro
-      = FileInfo.getControllingMacro(ExternalLookup))
-    // If the include file is part of a module, and we already know what its
-    // controlling macro is, then we've already parsed it and can safely just
-    // make it visible. This saves us needing to switch into the visibility
-    // state of the module just to check whether the macro is defined within it.
-    if (M || PP.isMacroDefined(ControllingMacro)) {
+      = FileInfo.getControllingMacro(ExternalLookup)) {
+    // If the header corresponds to a module, check whether the macro is already
+    // defined in that module rather than checking in the current set of visible
+    // modules.
+    if (M ? PP.isMacroDefinedInLocalModule(ControllingMacro, M)
+          : PP.isMacroDefined(ControllingMacro)) {
       ++NumMultiIncludeFileOptzn;
       return false;
     }
+  }
 
   // Increment the number of times this file has been included.
   ++FileInfo.NumIncludes;
diff --git a/lib/Lex/ModuleMap.cpp b/lib/Lex/ModuleMap.cpp
index e6fe389..96d3e4b 100644
--- a/lib/Lex/ModuleMap.cpp
+++ b/lib/Lex/ModuleMap.cpp
@@ -347,7 +347,7 @@ ModuleMap::KnownHeader ModuleMap::findModuleForHeader(const FileEntry *File) {
     // Iterate over all modules that 'File' is part of to find the best fit.
     for (KnownHeader &H : Known->second) {
       // Prefer a header from the current module over all others.
-      if (H.getModule() == CompilingModule)
+      if (H.getModule()->getTopLevelModule() == CompilingModule)
         return MakeResult(H);
       // Cannot use a module if it is unavailable.
       if (!H.getModule()->isAvailable())
@@ -1528,7 +1528,7 @@ void ModuleMapParser::parseModuleDecl() {
 ///     'extern' 'module' module-id string-literal
 void ModuleMapParser::parseExternModuleDecl() {
   assert(Tok.is(MMToken::ExternKeyword));
-  consumeToken(); // 'extern' keyword
+  SourceLocation ExternLoc = consumeToken(); // 'extern' keyword
 
   // Parse 'module' keyword.
   if (!Tok.is(MMToken::ModuleKeyword)) {
@@ -1567,7 +1567,7 @@ void ModuleMapParser::parseExternModuleDecl() {
         File, /*IsSystem=*/false,
         Map.HeaderInfo.getHeaderSearchOpts().ModuleMapFileHomeIsCwd
             ? Directory
-            : File->getDir());
+            : File->getDir(), ExternLoc);
 }
 
 /// \brief Parse a requires declaration.
@@ -2319,7 +2319,8 @@ bool ModuleMapParser::parseModuleMapFile() {
 }
 
 bool ModuleMap::parseModuleMapFile(const FileEntry *File, bool IsSystem,
-                                   const DirectoryEntry *Dir) {
+                                   const DirectoryEntry *Dir,
+                                   SourceLocation ExternModuleLoc) {
   llvm::DenseMap<const FileEntry *, bool>::iterator Known
     = ParsedModuleMap.find(File);
   if (Known != ParsedModuleMap.end())
@@ -2327,7 +2328,7 @@ bool ModuleMap::parseModuleMapFile(const FileEntry *File, bool IsSystem,
 
   assert(Target && "Missing target information");
   auto FileCharacter = IsSystem ? SrcMgr::C_System : SrcMgr::C_User;
-  FileID ID = SourceMgr.createFileID(File, SourceLocation(), FileCharacter);
+  FileID ID = SourceMgr.createFileID(File, ExternModuleLoc, FileCharacter);
   const llvm::MemoryBuffer *Buffer = SourceMgr.getBuffer(ID);
   if (!Buffer)
     return ParsedModuleMap[File] = true;
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index d52519e..64ce8c9 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -1088,6 +1088,7 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
       .Case("objc_default_synthesize_properties", LangOpts.ObjC2)
       .Case("objc_fixed_enum", LangOpts.ObjC2)
       .Case("objc_instancetype", LangOpts.ObjC2)
+      .Case("objc_kindof", LangOpts.ObjC2)
       .Case("objc_modules", LangOpts.ObjC2 && LangOpts.Modules)
       .Case("objc_nonfragile_abi", LangOpts.ObjCRuntime.isNonFragile())
       .Case("objc_property_explicit_atomic",
@@ -1106,6 +1107,8 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
       .Case("arc_cf_code_audited", true)
       .Case("objc_bridge_id", true)
       .Case("objc_bridge_id_on_typedefs", true)
+      .Case("objc_generics", LangOpts.ObjC2)
+      .Case("objc_generics_variance", LangOpts.ObjC2)
       // C11 features
       .Case("c_alignas", LangOpts.C11)
       .Case("c_alignof", LangOpts.C11)