h_ifunc_static.c revision 1.7 
1/*	$NetBSD: h_ifunc_static.c,v 1.7 2022/06/21 06:52:17 skrll Exp $	*/
2
3/*-
4 * Copyright (c) 2018 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Joerg Sonnenberger.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#if \
33    defined(__aarch64__) || \
34    defined(__arm__) || \
35    defined(__i386__) || \
36    defined(__powerpc__) || \
37    defined(__sparc__) || \
38    defined(__x86_64__)
39#include <stdlib.h>
40#include <string.h>
41
42static long long
43ifunc1(void)
44{
45	return 0xdeadbeefll;
46}
47
48static long long
49ifunc2(void)
50{
51	return 0xbeefdeadll;
52}
53
54static __attribute__((used))
55long long (*resolve_ifunc(void))(void)
56{
57	const char *e = getenv("USE_IFUNC2");
58	return e && strcmp(e, "1") == 0 ? ifunc2 : ifunc1;
59}
60
61__ifunc(ifunc, resolve_ifunc);
62extern long long ifunc(void);
63
64int
65main(int argc, char **argv)
66{
67
68	if (argc != 2)
69		return 1;
70	return atoll(argv[1]) != ifunc();
71}
72#else
73int
74main(int argc, char **argv)
75{
76	return 127;
77}
78#endif
79