1  extern void abort (void);
       2  
       3  /* Since GCC 5 folds symbol address comparison, assuming each symbol has
       4     different address,  &foo == &bar is always false for GCC 5.  Use
       5     check_ptr_eq to check if two functions are the same.  */
       6  
       7  void 
       8  check_ptr_eq (void (*f1) (void), void (*f2) (void))
       9  {
      10    if (f1 != f2)
      11      abort ();
      12  }