gcc/testsuite/gcc.c-torture/execute/va-arg-21.c

   1 /* Copyright (C) 2000  Free Software Foundation.
   2
   3    If the argument to va_end() has side effects, test whether side
   4    effects from that argument are honored.
   5
   6    Written by Kaveh R. Ghazi, 10/31/2000.  */
   7
   8 #include <stdarg.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11
  12 #ifndef __GNUC__
  13 #define __attribute__(x)
  14 #endif
  15
  16 static void __attribute__ ((__format__ (__printf__, 1, 2)))
  17 doit (const char *s, ...)
  18 {
  19   va_list *ap_array[3], **ap_ptr = ap_array;
  20
  21   ap_array[0] = malloc (sizeof(va_list));
  22   ap_array[1] = NULL;
  23   ap_array[2] = malloc (sizeof(va_list));
  24
  25   va_start (*ap_array[0], s);
  26   vprintf (s, **ap_ptr);
  27   /* Increment the va_list pointer once.  */
  28   va_end (**ap_ptr++);
  29
  30   /* Increment the va_list pointer a second time.  */
  31   ap_ptr++;
  32
  33   va_start (*ap_array[2], s);
  34   /* If we failed to increment ap_ptr twice, then the parameter passed
  35      in here will dereference NULL and should cause a crash.  */
  36   vprintf (s, **ap_ptr);
  37   va_end (**ap_ptr);
  38
  39   /* Just in case, If *ap_ptr is NULL abort anyway.  */
  40   if (*ap_ptr == 0)
  41     abort();
  42 }
  43
  44 int main()
  45 {
  46   doit ("%s", "hello world\n");
  47   exit (0);
  48 }