Testing address space layout randomization on Leopard

aslr-test.c

/*
 A small program to test address space layout randomization (ASLR) on Leopard,
 by Torsten Becker <torsten.becker@gmail.com>, 2009.
 
 The presentation from a Apple guy at
   http://www.slideshare.net/guest4c923d/jordan-hubbard-talk-lisa-presentation
 suggests to compile with -pie but it doesn't work for me, I get the same
 output every time which means it's not random, check it yourself:

 $ gcc -fPIC -Wl,-pie aslr-test.c && ./a.out
*/

#include <stdio.h>
#include <stdarg.h>

int main (int argc, char const *argv[])
{
  int var = 23;
  printf("stack:  0x%x\n"
         "printf: 0x%x\n"
         "ret:    0x%x "
         "(should not be 0xc3 which is \"ret\" and enables return from libc)\n",
      &var, &printf,
      *((unsigned char*)0x942b2fc2) /* a ret in printf */);
  
  return 0;
}