fix a segfault in cases where there are no cases.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@41317 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/switch.c b/test/Sema/switch.c
index ce195b1..a55831d 100644
--- a/test/Sema/switch.c
+++ b/test/Sema/switch.c
@@ -15,3 +15,7 @@
   }
 }
 
+void test3(void) { 
+  switch (0); 
+}
+