1 files changed, 29 insertions, 0 deletions
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index b7bbb9dc7be1..e16a9b3ee3b5 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -292,6 +292,33 @@ static bool checkLanguageOptions(const LangOptions &LangOpts,
     return true;
   }
 
+  // Sanitizer feature mismatches are treated as compatible differences. If
+  // compatible differences aren't allowed, we still only want to check for
+  // mismatches of non-modular sanitizers (the only ones which can affect AST
+  // generation).
+  if (!AllowCompatibleDifferences) {
+    SanitizerMask ModularSanitizers = getPPTransparentSanitizers();
+    SanitizerSet ExistingSanitizers = ExistingLangOpts.Sanitize;
+    SanitizerSet ImportedSanitizers = LangOpts.Sanitize;
+    ExistingSanitizers.clear(ModularSanitizers);
+    ImportedSanitizers.clear(ModularSanitizers);
+    if (ExistingSanitizers.Mask != ImportedSanitizers.Mask) {
+      const std::string Flag = "-fsanitize=";
+      if (Diags) {
+#define SANITIZER(NAME, ID)                                                    \
+  {                                                                            \
+    bool InExistingModule = ExistingSanitizers.has(SanitizerKind::ID);         \
+    bool InImportedModule = ImportedSanitizers.has(SanitizerKind::ID);         \
+    if (InExistingModule != InImportedModule)                                  \
+      Diags->Report(diag::err_pch_targetopt_feature_mismatch)                  \
+          << InExistingModule << (Flag + NAME);                                \
+  }
+#include "clang/Basic/Sanitizers.def"
+      }
+      return true;
+    }
+  }
+
   return false;
 }
 
@@ -3670,6 +3697,8 @@ static void updateModuleTimestamp(ModuleFile &MF) {
   if (EC)
     return;
   OS << "Timestamp file\n";
+  OS.close();
+  OS.clear_error(); // Avoid triggering a fatal error.
 }
 
 /// \brief Given a cursor at the start of an AST file, scan ahead and drop the