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/2002-08-02-UnionTest.c b/test/CFrontend/2002-08-02-UnionTest.c
index 25bf157..b9e2c2e 100644
--- a/test/CFrontend/2002-08-02-UnionTest.c
+++ b/test/CFrontend/2002-08-02-UnionTest.c
@@ -1,3 +1,5 @@
+// RUN: %llvmgcc -S %s -o - | llvm-as -f -o /dev/null
+
 /* In this testcase, the return value of foo() is being promotedto a register
  * which breaks stuff
  */