1  /* Simple check that sibling calls are performed from a
       2     void non-leaf-function taking no arguments calling itself.
       3  
       4     Copyright (C) 2002 Free Software Foundation Inc.
       5     Contributed by Hans-Peter Nilsson  <hp@bitrange.com>  */
       6  
       7  /* { dg-do run } */
       8  /* { dg-options "-O2 -foptimize-sibling-calls" } */
       9  
      10  /* The option -foptimize-sibling-calls is the default, but serves as
      11     marker.  Self-recursion tail calls are optimized for all targets,
      12     regardless of presence of sibcall patterns.  */
      13  
      14  extern void abort (void);
      15  extern void exit (int);
      16  
      17  extern void recurser_void (void);
      18  extern void track (void);
      19  
      20  int n = 0;
      21  int main ()
      22  {
      23    recurser_void ();
      24    exit (0);
      25  }
      26  
      27  void
      28  recurser_void (void)
      29  {
      30    if (n == 0 || n == 7)
      31      track ();
      32  
      33    if (n == 10)
      34      return;
      35    n++;
      36    recurser_void ();
      37  }
      38  
      39  void *trackpoint;
      40  
      41  void __attribute__ ((noipa))
      42  track ()
      43  {
      44    char stackpos[1];
      45  
      46    if (n == 0)
      47      trackpoint = stackpos;
      48    else if (n != 7 || trackpoint != stackpos)
      49      abort ();
      50  }