diff --git a/lib/CodeGen/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter.cpp
index 1e104fccc8d..0cf5823bb8c 100644
--- a/lib/CodeGen/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter.cpp
@@ -19,7 +19,7 @@
 using namespace llvm;
 
 bool AsmPrinter::doInitialization(Module &M) {
-  Mang = new Mangler(M);
+  Mang = new Mangler(M, UsesUnderscorePrefix);
   return false;
 }