1  /* PR middle-end/17813 */
       2  /* Origin: Tom Hughes <tom@compton.nu> */
       3  /* { dg-do run { target i?86-*-linux* i?86-*-gnu* x86_64-*-linux* } } */
       4  /* { dg-options "-O -fomit-frame-pointer" } */
       5  /* { dg-options "-O -fomit-frame-pointer -march=i386" { target { { i?86-*-* x86_64-*-* } && ia32 } } } */
       6  
       7  #include <setjmp.h>
       8  #include <signal.h>
       9  #include <stdlib.h>
      10  
      11  static jmp_buf segv_jmpbuf;
      12  
      13  static void segv_handler(int seg)
      14  {
      15     __builtin_longjmp(segv_jmpbuf, 1);
      16  }
      17  
      18  static int is_addressable(void *p, size_t size)
      19  {
      20     volatile char * volatile cp = (volatile char *)p;
      21     volatile int ret;
      22     struct sigaction sa, origsa;
      23     sigset_t mask;
      24     
      25     sa.sa_handler = segv_handler;
      26     sa.sa_flags = 0;
      27     sigfillset(&sa.sa_mask);
      28     sigaction(SIGSEGV, &sa, &origsa);
      29     sigprocmask(SIG_SETMASK, NULL, &mask);
      30  
      31     if (__builtin_setjmp(segv_jmpbuf) == 0) {
      32        while(size--)
      33  	 *cp++;
      34        ret = 1;
      35      } else
      36        ret = 0;
      37  
      38     sigaction(SIGSEGV, &origsa, NULL);
      39     sigprocmask(SIG_SETMASK, &mask, NULL);
      40  
      41     return ret;
      42  }
      43  
      44  int main(int argc, char **argv)
      45  {
      46     is_addressable(0x0, 1);
      47     return 0;
      48  }