glibc/string/rawmemchr.c
Joseph Myers 8fa11673d6 Fix rawmemchr build with GCC 8.
The default rawmemchr implementation uses memchr with size (size_t)-1,
which produces a warning with current GCC mainline.  The warning seems
reasonable for normal code, so this patch uses the DIAG_* macros to
disable it.

Tested (compilation of glibc only) with build-many-glibcs.py for
arm-linux-gnueabi and powerpc64le-linux-gnu, two architectures for
which the build was previously failing.  Note that the glibc testsuite
will still fail to build with GCC mainline because of
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80669>.

	* string/rawmemchr.c: Include <libc-diag.h>.
	(RAWMEMCHR): Disable -Wstringop-overflow around call to memchr
	with size (size_t)-1.
2017-05-10 00:25:59 +00:00

42 lines
1.4 KiB
C

/* Copyright (C) 1991-2017 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
<http://www.gnu.org/licenses/>. */
#include <string.h>
#include <libc-diag.h>
#ifndef RAWMEMCHR
# define RAWMEMCHR __rawmemchr
#endif
/* Find the first occurrence of C in S. */
void *
RAWMEMCHR (const void *s, int c)
{
DIAG_PUSH_NEEDS_COMMENT;
#if __GNUC_PREREQ (7, 0)
/* GCC 8 warns about the size passed to memchr being larger than
PTRDIFF_MAX; the use of SIZE_MAX is deliberate here. */
DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-overflow=");
#endif
if (c != '\0')
return memchr (s, c, (size_t)-1);
DIAG_POP_NEEDS_COMMENT;
return (char *)s + strlen (s);
}
libc_hidden_def (__rawmemchr)
weak_alias (__rawmemchr, rawmemchr)