diff --git a/lib/VMCore/Core.cpp b/lib/VMCore/Core.cpp
index a044fc5b1a0..5883cdbfbbb 100644
--- a/lib/VMCore/Core.cpp
+++ b/lib/VMCore/Core.cpp
@@ -1215,14 +1215,14 @@ void LLVMSetGC(LLVMValueRef Fn, const char *GC) {
 void LLVMAddFunctionAttr(LLVMValueRef Fn, LLVMAttribute PA) {
   Function *Func = unwrap<Function>(Fn);
   const AttrListPtr PAL = Func->getAttributes();
-  const AttrListPtr PALnew = PAL.addAttr(0, PA);
+  const AttrListPtr PALnew = PAL.addAttr(~0U, PA);
   Func->setAttributes(PALnew);
 }
 
 void LLVMRemoveFunctionAttr(LLVMValueRef Fn, LLVMAttribute PA) {
   Function *Func = unwrap<Function>(Fn);
   const AttrListPtr PAL = Func->getAttributes();
-  const AttrListPtr PALnew = PAL.removeAttr(0, PA);
+  const AttrListPtr PALnew = PAL.removeAttr(~0U, PA);
   Func->setAttributes(PALnew);
 }