1  /* { dg-do compile } */
       2  /* { dg-options "-O2 -fdump-tree-pre" } */
       3  
       4  _Bool f1(unsigned x, unsigned y, unsigned *res, int flag, _Bool *t)
       5  {
       6    if (flag)
       7      *t = __builtin_add_overflow(x, y, res);
       8    unsigned res1;
       9    _Bool t1 = __builtin_add_overflow(x, y, &res1);
      10    *res -= res1;
      11    return *t==t1;
      12  }
      13  
      14  /* We should hoist the .ADD_OVERFLOW to before the check.  */
      15  /* { dg-final { scan-tree-dump-times "ADD_OVERFLOW" 1 "pre" } } */