Fix an assert when assigning a boolean value to a bitfield of type _Bool.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@101678 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/bitfield-2.c b/test/CodeGen/bitfield-2.c
index 79033d7..94f275d 100644
--- a/test/CodeGen/bitfield-2.c
+++ b/test/CodeGen/bitfield-2.c
@@ -205,3 +205,19 @@
   res ^= g5.f0 ^ g5.f1 ^ g5.f2;
   return res;
 }
+
+struct A {
+  _Bool b : 2;
+};
+
+// CHECK-OPT: define zeroext i1 @test_6()
+// CHECK-OPT: ret i1 true
+// CHECK-OPT: }
+_Bool test_6() {
+  struct A a;
+  
+  a.b = (_Bool)0;
+  
+  return (a.b = !a.b);
+}
+