1  /* { dg-do compile } */
       2  /* { dg-options "-O -fdump-tree-forwprop1" } */
       3  
       4  _Bool foo (_Bool a, _Bool b)
       5  {
       6    return a == (!b);
       7  }
       8  
       9  /* { dg-final { scan-tree-dump "\[ab\]_\[0-9\]+\\(D\\) \\\^ \[ba\]_\[0-9\]+\\(D\\)" "forwprop1" } } */