Silliness with commas, as reported at http://blog.regehr.org/archives/558 .  As it turns out, this is my fault for not noticing this was an issue when I was looking at this a long time ago. :(

llvm-svn: 135026
diff --git a/clang/test/Sema/bitfield.c b/clang/test/Sema/bitfield.c
index 49c1c7d..a1ce894 100644
--- a/clang/test/Sema/bitfield.c
+++ b/clang/test/Sema/bitfield.c
@@ -32,6 +32,7 @@
 
 struct {unsigned x : 2;} x2;
 __typeof__((x.x+=1)+1) y;
+__typeof__((0,x.x)+1) y;
 __typeof__(x.x<<1) y;
 int y;