diff --git a/test/CodeGen/2008-01-25-ByValReadNone.c b/test/CodeGen/2008-01-25-ByValReadNone.c
index ca21f6c443a0a3f55f663e529bd4b033d44fc5a0..b3b5861a4dc2193ef91e50b26c35b56c56e7d9e6 100644
--- a/test/CodeGen/2008-01-25-ByValReadNone.c
+++ b/test/CodeGen/2008-01-25-ByValReadNone.c
@@ -1,7 +1,8 @@
-// RUN: %clang_cc1 -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s | FileCheck %s
 
 // XFAIL: mips
 
+// It could hit in @llvm.memcpy with "-triple x86_64-(mingw32|win32)".
 // CHECK-NOT: readonly
 // CHECK-NOT: readnone