diff --git a/include/llvm/Support/Mangler.h b/include/llvm/Support/Mangler.h
index c5edd3d2a62..3c2050324dd 100644
--- a/include/llvm/Support/Mangler.h
+++ b/include/llvm/Support/Mangler.h
@@ -64,7 +64,8 @@ public:
   /// does this for you, so there's no point calling it on the result
   /// from getValueName.
   ///
-  static std::string makeNameProper(const std::string &x);
+  static std::string makeNameProper(const std::string &x,
+                                    const char *Prefix = "");
 };
 
 } // End llvm namespace