var x: int;

var y: int;

procedure p();
  modifies x;



implementation p()
{

  A:
    assume {:inferred} true;
    assume -1 <= x;
    assume {:inferred} -1 <= x;
    goto B, E;

  E:
    assume {:inferred} true;
    assume {:inferred} true;
    return;

  B:
    assume {:inferred} -1 <= x;
    assume x < y;
    assume {:inferred} -1 <= x && 0 <= y;
    goto C, E;

  C:
    assume {:inferred} -1 <= x && 0 <= y;
    x := x * x;
    assume {:inferred} x < 2 && 0 <= y;
    goto D, E;

  D:
    assume {:inferred} x < 2 && 0 <= y;
    x := y;
    assume {:inferred} 0 <= x && 0 <= y;
    return;
}



Boogie program verifier finished with 0 verified, 0 errors