1 /* Test printf with x86-specific non-normal long double value.
2 Copyright (C) 2020-2021 Free Software Foundation, Inc.
3
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20 #include <stdio.h>
21 #include <string.h>
22 #include <support/check.h>
23
24 /* Fill the stack with non-zero values. This makes a crash in
25 snprintf more likely. */
26 static void __attribute__ ((noinline, noclone))
fill_stack(void)27 fill_stack (void)
28 {
29 char buffer[65536];
30 memset (buffer, 0xc0, sizeof (buffer));
31 asm ("" ::: "memory");
32 }
33
34 static int
do_test(void)35 do_test (void)
36 {
37 fill_stack ();
38
39 long double value;
40 memcpy (&value, "\x00\x04\x00\x00\x00\x00\x00\x00\x00\x04", 10);
41
42 char buf[30];
43 int ret = snprintf (buf, sizeof (buf), "%Lg", value);
44 TEST_COMPARE (ret, strlen (buf));
45 TEST_COMPARE_STRING (buf, "nan");
46 return 0;
47 }
48
49 #include <support/test-driver.c>
50