1 struct A {
   2         int a[1];
   3         int b;
   4 };
   5 
   6 extern int c;
   7 
   8 static int o[] = {
   9         [__builtin_offsetof(struct A, b)] = 0,          // OK
  10         [__builtin_offsetof(struct A, a[0])] = 0,       // OK
  11         [__builtin_offsetof(struct A, a[0*0])] = 0,     // OK
  12         [__builtin_offsetof(struct A, a[c])] = 0        // KO
  13 };
  14 
  15 /*
  16  * check-name: constexprness __builtin_offsetof()
  17  *
  18  * check-error-start
  19 constexpr-offsetof.c:12:39: error: bad constant expression
  20  * check-error-end
  21  */