2 files changed, 18 insertions, 6 deletions
diff --git a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
index a4d1b83..cdcf7a8 100644
--- a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
+++ b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
@@ -1867,12 +1867,18 @@ Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
     // distinct.  It's always distinct.
     IsDistinct = true;
 
+    const auto LangVersionMask = (uint64_t(1) << 63);
+    const bool HasVersionedLanguage = Record[1] & LangVersionMask;
+
     auto *CU = DICompileUnit::getDistinct(
-        Context, DISourceLanguageName(Record[1]), getMDOrNull(Record[2]),
-        getMDString(Record[3]), Record[4], getMDString(Record[5]), Record[6],
-        getMDString(Record[7]), Record[8], getMDOrNull(Record[9]),
-        getMDOrNull(Record[10]), getMDOrNull(Record[12]),
-        getMDOrNull(Record[13]),
+        Context,
+        HasVersionedLanguage
+            ? DISourceLanguageName(Record[1] & ~LangVersionMask, 0)
+            : DISourceLanguageName(Record[1]),
+        getMDOrNull(Record[2]), getMDString(Record[3]), Record[4],
+        getMDString(Record[5]), Record[6], getMDString(Record[7]), Record[8],
+        getMDOrNull(Record[9]), getMDOrNull(Record[10]),
+        getMDOrNull(Record[12]), getMDOrNull(Record[13]),
         Record.size() <= 15 ? nullptr : getMDOrNull(Record[15]),
         Record.size() <= 14 ? 0 : Record[14],
         Record.size() <= 16 ? true : Record[16],
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 7ed140d..0ca55a26 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -2108,7 +2108,13 @@ void ModuleBitcodeWriter::writeDICompileUnit(const DICompileUnit *N,
   assert(N->isDistinct() && "Expected distinct compile units");
   Record.push_back(/* IsDistinct */ true);
 
-  Record.push_back(N->getSourceLanguage().getUnversionedName());
+  auto Lang = N->getSourceLanguage();
+  Record.push_back(Lang.getName());
+  // Set bit so the MetadataLoader can distniguish between versioned and
+  // unversioned names.
+  if (Lang.hasVersionedName())
+    Record.back() ^= (uint64_t(1) << 63);
+
   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
   Record.push_back(VE.getMetadataOrNullID(N->getRawProducer()));
   Record.push_back(N->isOptimized());