1  /* this is another case where phiopt
       2     would create -signed1bit which is undefined. */
       3  struct {
       4    int a:1;
       5  } b;
       6  int *c = (int *)&b, d;
       7  int main() {
       8    d = c && (b.a = (d < 0) ^ 3);
       9    if (d != 1)
      10      __builtin_abort();
      11    return 0;
      12  }