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/* Copyright (C) 2000 Free Software Foundation.
If the argument to va_end() has side effects, test whether side
effects from that argument are honored.
Written by Kaveh R. Ghazi, 10/31/2000. */
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#ifndef __GNUC__
#define __attribute__(x)
#endif
static void __attribute__ ((__format__ (__printf__, 1, 2)))
doit (const char *s, ...)
{
va_list *ap_array[3], **ap_ptr = ap_array;
ap_array[0] = malloc (sizeof(va_list));
ap_array[1] = NULL;
ap_array[2] = malloc (sizeof(va_list));
va_start (*ap_array[0], s);
vprintf (s, **ap_ptr);
/* Increment the va_list pointer once. */
va_end (**ap_ptr++);
/* Increment the va_list pointer a second time. */
ap_ptr++;
va_start (*ap_array[2], s);
/* If we failed to increment ap_ptr twice, then the parameter passed
in here will dereference NULL and should cause a crash. */
vprintf (s, **ap_ptr);
va_end (**ap_ptr);
/* Just in case, If *ap_ptr is NULL abort anyway. */
if (*ap_ptr == 0)
abort();
}
int main()
{
doit ("%s", "hello world\n");
exit (0);
}
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