oops, this is the real fix.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@40766 91177308-0d34-0410-b5e6-96231b3b80d8

test/Sema/array-constraint.c

@@ -2,7 +2,7 @@
 
 struct s; 
 struct s* t (struct s z[]) {   // expected-error {{array has incomplete element type}}
-  return z;                    // expected-error {{incompatible pointer type returning}}
+  return z;                    // expected-warning {{incompatible pointer type returning}}
 }
 
 void *k (void l[2]) {          // expected-error {{array has incomplete element type}}