Adding RUN lines.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17532 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CFrontend/2003-10-02-UnionLValueError.c b/test/CFrontend/2003-10-02-UnionLValueError.c
index 82693c7..732f93a 100644
--- a/test/CFrontend/2003-10-02-UnionLValueError.c
+++ b/test/CFrontend/2003-10-02-UnionLValueError.c
@@ -1,3 +1,5 @@
+// RUN: %llvmgcc -S %s -o - | llvm-as -f -o /dev/null
+
 union U{
   int i[8];
   char s[80];