void abort() { };
                                                                                                                                                          
                                                                           

/*@ 
    requires ((1 <= \old(cond))) && (cond != 0);
    ensures ((1 <= \old(cond))) && (1);
@*/
void __VERIFIER_assert(int cond) {
  if (!(cond)) {
    ERROR: {/*@ assert(0); */;abort();}
  }
  return;
}

int main() {
  unsigned int x = 1;
  unsigned int y = 0;

/*@
loop invariant (((y == 0) || (x == 0)));
@*/
  while (y < 1024) {
    x = 0;
    y++;
  }

  __VERIFIER_assert(x == 0);
}