Fix PR3938 by taking into account C99 6.10p4.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@69413 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Preprocessor/if_warning.c b/test/Preprocessor/if_warning.c
index acb6d5e..5fc8c34 100644
--- a/test/Preprocessor/if_warning.c
+++ b/test/Preprocessor/if_warning.c
@@ -11,3 +11,10 @@
 #if defined(foo)
 #endif
 
+
+// PR3938
+#if 0
+#ifdef D
+#else 1       // Should not warn due to C99 6.10p4
+#endif
+#endif