3 files changed, 14 insertions, 8 deletions
diff --git a/llvm/lib/VMCore/LLVMContextImpl.h b/llvm/lib/VMCore/LLVMContextImpl.h
index f98526de650..1a4bf6d7b44 100644
--- a/llvm/lib/VMCore/LLVMContextImpl.h
+++ b/llvm/lib/VMCore/LLVMContextImpl.h
@@ -234,7 +234,7 @@ public:
                          DenseMapAPFloatKeyInfo> FPMapTy;
   FPMapTy FPConstants;
   
-  StringMap<MDString*> MDStringCache;
+  StringMap<Value*> MDStringCache;
   
   FoldingSet<MDNode> MDNodeSet;
   // MDNodes may be uniqued or not uniqued.  When they're not uniqued, they
diff --git a/llvm/lib/VMCore/Metadata.cpp b/llvm/lib/VMCore/Metadata.cpp
index e6fd64c0afa..55de0dc6515 100644
--- a/llvm/lib/VMCore/Metadata.cpp
+++ b/llvm/lib/VMCore/Metadata.cpp
@@ -31,16 +31,17 @@ using namespace llvm;
 
 void MDString::anchor() { }
 
-MDString::MDString(LLVMContext &C, StringRef S)
-  : Value(Type::getMetadataTy(C), Value::MDStringVal), Str(S) {}
+MDString::MDString(LLVMContext &C)
+  : Value(Type::getMetadataTy(C), Value::MDStringVal) {}
 
 MDString *MDString::get(LLVMContext &Context, StringRef Str) {
   LLVMContextImpl *pImpl = Context.pImpl;
-  StringMapEntry<MDString *> &Entry =
+  StringMapEntry<Value*> &Entry =
     pImpl->MDStringCache.GetOrCreateValue(Str);
-  MDString *&S = Entry.getValue();
-  if (!S) S = new MDString(Context, Entry.getKey());
-  return S;
+  Value *&S = Entry.getValue();
+  if (!S) S = new MDString(Context);
+  S->setValueName(&Entry);
+  return cast<MDString>(S);
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/VMCore/Value.cpp b/llvm/lib/VMCore/Value.cpp
index 788f4191f5b..4006b2c5541 100644
--- a/llvm/lib/VMCore/Value.cpp
+++ b/llvm/lib/VMCore/Value.cpp
@@ -76,7 +76,7 @@ Value::~Value() {
 
   // If this value is named, destroy the name.  This should not be in a symtab
   // at this point.
-  if (Name)
+  if (Name && SubclassID != MDStringVal)
     Name->Destroy();
 
   // There should be no uses of this object anymore, remove it.
@@ -170,6 +170,9 @@ StringRef Value::getName() const {
 }
 
 void Value::setName(const Twine &NewName) {
+  assert(SubclassID != MDStringVal &&
+         "Cannot set the name of MDString with this method!");
+
   // Fast path for common IRBuilder case of setName("") when there is no name.
   if (NewName.isTriviallyEmpty() && !hasName())
     return;
@@ -228,6 +231,8 @@ void Value::setName(const Twine &NewName) {
 /// takeName - transfer the name from V to this value, setting V's name to
 /// empty.  It is an error to call V->takeName(V).
 void Value::takeName(Value *V) {
+  assert(SubclassID != MDStringVal && "Cannot take the name of an MDString!");
+
   ValueSymbolTable *ST = 0;
   // If this value has a name, drop it.
   if (hasName()) {