1  /* { dg-do compile } */
       2  /* { dg-options "-O2" } */
       3  
       4  #define TEN(x) x x x x x x x x x x
       5  #define THOUSAND(x) TEN (TEN (TEN (x)))
       6  
       7  int
       8  foo (int x, int y)
       9  {
      10    register int a = y + 57;
      11    register int b = y + 31;
      12  
      13    while (x-- > 0)
      14      {
      15        THOUSAND (a += b; b -= a;)
      16      }
      17    return a + b;
      18  }