diff --git a/test/CodeGen/union.c b/test/CodeGen/union.c
index 1e4346d..616cf56 100644
--- a/test/CodeGen/union.c
+++ b/test/CodeGen/union.c
@@ -36,3 +36,6 @@
 } q;
 int qfunc() {q buf; unsigned char* x = buf.x;}
 
+union RR {_Bool a : 1;} RRU;
+int RRF(void) {return RRU.a;}
+