20000412-2.c

this is a gcc file, you can download it and learn its usetility, for further detail please look at t

int f(int a,int *y)
{
  int x = a;

  if (a==0)
    return *y;

  return f(a-1,&x);
}

int main(int argc,char **argv)
{
  if (f (100, (int *) 0) != 1)
    abort ();
  exit (0);
}