glibc/stdlib/tst-labs.c
Florian Weimer 10a81dd4cf stdlib: Avoid undefined behavior in stdlib/tst-labs
The last loop could attempt to overflow beyond INT_MAX on 32-bit
architectures.

Also switch to GNU style.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-05-17 08:23:59 +02:00

53 lines
1.5 KiB
C

/* Basic tests for labs.
Copyright (C) 2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <limits.h>
#include <stdlib.h>
#include <support/check.h>
#define LARGE_PRIME 49999
static int do_test (void)
{
long int i;
TEST_COMPARE (labs (LONG_MAX), LONG_MAX);
TEST_COMPARE (labs (LONG_MIN + 1), LONG_MAX);
TEST_COMPARE (labs (-1), 1);
TEST_COMPARE (labs (0), 0);
TEST_COMPARE (labs (1), 1);
for (i = LONG_MIN + 1; i < LONG_MIN + INT_MAX; i += LARGE_PRIME)
TEST_COMPARE (labs (i), -i);
for (i = LONG_MAX - INT_MAX; i < LONG_MAX - LARGE_PRIME;
i += LARGE_PRIME)
TEST_COMPARE (labs (i), i);
for (i = INT_MIN + 1; i < 0; i += LARGE_PRIME)
TEST_COMPARE (labs (i), -i);
for (i = 0; i <= INT_MAX - LARGE_PRIME; i += LARGE_PRIME)
TEST_COMPARE (labs (i), i);
return EXIT_SUCCESS;
}
#include <support/test-driver.c>