add testcase we already handle.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@54967 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/init.c b/test/Sema/init.c
index b57f046..f6cf9c3 100644
--- a/test/Sema/init.c
+++ b/test/Sema/init.c
@@ -50,3 +50,7 @@
   return pbool2;
 }
 
+
+// rdar://5870981
+union { float f; unsigned u; } u = { 1.0f };
+