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: __builtin_offsetof() constness verification. 17 * 18 * check-error-start 19 constexpr-offsetof.c:12:39: error: bad constant expression 20 * check-error-end 21 */ 22