diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index a9b99b1bd93..37297d6dccd 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -42,7 +42,7 @@
 using namespace llvm;
 
 static cl::opt<bool>
-NoBuiltin("no-builtin",
+NoBuiltin("no-builtin", cl::init(false),
            cl::desc("Don't recognize built-in functions that do not begin "
                     "with `__builtin_' as prefix"));
 
diff --git a/test/CodeGen/X86/darwin-bzero.ll b/test/CodeGen/X86/darwin-bzero.ll
index c292140e108..941577eae1c 100644
--- a/test/CodeGen/X86/darwin-bzero.ll
+++ b/test/CodeGen/X86/darwin-bzero.ll
@@ -1,4 +1,5 @@
 ; RUN: llvm-as < %s | llc -mtriple=i386-apple-darwin10 | grep __bzero
+; RUN: llvm-as < %s | llc -mtriple=i386-apple-darwin10 -no-builtin | grep _bzero
 
 declare void @llvm.memset.i32(i8*, i8, i32, i32)