diff --git a/include/llvm/Metadata.h b/include/llvm/Metadata.h
index a24ebe61dee..91ab55b175f 100644
--- a/include/llvm/Metadata.h
+++ b/include/llvm/Metadata.h
@@ -57,8 +57,8 @@ class MDString : public MetadataBase {
 
   StringRef Str;
 protected:
-  explicit MDString(LLVMContext &C, const char *begin, unsigned l)
-    : MetadataBase(Type::getMetadataTy(C), Value::MDStringVal), Str(begin, l) {}
+  explicit MDString(LLVMContext &C, StringRef S)
+    : MetadataBase(Type::getMetadataTy(C), Value::MDStringVal), Str(S) {}
 
 public:
   static MDString *get(LLVMContext &Context, StringRef Str);
diff --git a/lib/VMCore/Metadata.cpp b/lib/VMCore/Metadata.cpp
index 8b37681b96b..3e3ea7725a5 100644
--- a/lib/VMCore/Metadata.cpp
+++ b/lib/VMCore/Metadata.cpp
@@ -33,7 +33,8 @@ MDString *MDString::get(LLVMContext &Context, StringRef Str) {
   MDString *&S = Entry.getValue();
   if (S) return S;
   
-  return S = new MDString(Context, Entry.getKeyData(), Entry.getKeyLength());
+  return S = 
+    new MDString(Context, StringRef(Entry.getKeyData(), Entry.getKeyLength()));
 }
 
 //===----------------------------------------------------------------------===//