diff --git a/test/CodeGen/builtins-arm64.c b/test/CodeGen/builtins-arm64.c
index 6e246ed7ce2aee2391fb31983f89e89e577e4f81..9e3460c866081ec006455d3e42a3ad9fe9f50b41 100644
--- a/test/CodeGen/builtins-arm64.c
+++ b/test/CodeGen/builtins-arm64.c
@@ -6,11 +6,11 @@ void f0(void *a, void *b) {
 }
 
 // CHECK: call {{.*}} @llvm.aarch64.rbit.i32(i32 %a)
-void rbit(unsigned a) {
-  __builtin_arm_rbit(a);
+unsigned rbit(unsigned a) {
+  return __builtin_arm_rbit(a);
 }
 
 // CHECK: call {{.*}} @llvm.aarch64.rbit.i64(i64 %a)
-void rbit64(unsigned long long a) {
-  __builtin_arm_rbit64(a);
+unsigned long long rbit64(unsigned long long a) {
+  return __builtin_arm_rbit64(a);
 }