1  typedef void (*func_p) (void);
       2  
       3  extern func_p bar1_p (void);
       4  extern func_p bar2_p (void);
       5  extern func_p bar3_p (void);
       6  
       7  int
       8  main ()
       9  {
      10    func_p f;
      11    f = bar1_p ();
      12    f ();
      13    f = bar2_p ();
      14    f ();
      15    f = bar3_p ();
      16    f ();
      17    return 0;
      18  }