1  
       2  /* { dg-do compile } */
       3  /* { dg-options "-O2" } */
       4  
       5  int a = 0, b = 0;
       6  void fn1() {
       7      int c = 0;
       8      for (; a; a--)
       9        c += b;
      10      while ((c - 1) & c)
      11        ;
      12  }