1  /* { dg-do compile } */
       2  /* { dg-options "-O" } */
       3  /* { dg-final { scan-assembler-not "negl" } } */
       4  /* { dg-final { scan-assembler-not "andl" } } */
       5  
       6  int 
       7  test(int n)
       8  {
       9    if ((n & -n) != n)
      10      __builtin_unreachable();
      11    return n;
      12  }