add support for zero initialized unions, patch by Tim Northover!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99818 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Feature/unions.ll b/test/Feature/unions.ll
index 9d6c36b..3cf8c3c 100644
--- a/test/Feature/unions.ll
+++ b/test/Feature/unions.ll
@@ -6,7 +6,9 @@
 
 @union1 = constant union { i32, i8 } { i32 4 }
 @union2 = constant union { i32, i8 } insertvalue(union { i32, i8 } undef, i32 4, 0)
+@union3 = common global %union.anon zeroinitializer, align 8 
 
 define void @"Unions" () {
   ret void
 }
+