--- /dev/null
--- /dev/null
++/* ignore a function return without a compiler warning
++
++ Copyright (C) 2008-2011 Free Software Foundation, Inc.
++
++ This program is free software: you can redistribute it and/or modify
++ it under the terms of the GNU General Public License as published by
++ the Free Software Foundation; either version 3 of the License, or
++ (at your option) any later version.
++
++ This program 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 General Public License for more details.
++
++ You should have received a copy of the GNU General Public License
++ along with this program. If not, see <http://www.gnu.org/licenses/>. */
++
++/* Written by Jim Meyering, Eric Blake and Pádraig Brady. */
++
++/* Use "ignore_value" to avoid a warning when using a function declared with
++ gcc's warn_unused_result attribute, but for which you really do want to
++ ignore the result. Traditionally, people have used a "(void)" cast to
++ indicate that a function's return value is deliberately unused. However,
++ if the function is declared with __attribute__((warn_unused_result)),
++ gcc issues a warning even with the cast.
++
++ Caution: most of the time, you really should heed gcc's warning, and
++ check the return value. However, in those exceptional cases in which
++ you're sure you know what you're doing, use this function.
++
++ For the record, here's one of the ignorable warnings:
++ "copy.c:233: warning: ignoring return value of 'fchown',
++ declared with attribute warn_unused_result". */
++
++#ifndef _GL_IGNORE_VALUE_H
++# define _GL_IGNORE_VALUE_H
++
++# ifndef ATTRIBUTE_DEPRECATED
++/* The __attribute__((__deprecated__)) feature
++ is available in gcc versions 3.1 and newer. */
++# if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 1)
++# define ATTRIBUTE_DEPRECATED /* empty */
++# else
++# define ATTRIBUTE_DEPRECATED __attribute__ ((__deprecated__))
++# endif
++# endif
++
++/* The __attribute__((__warn_unused_result__)) feature
++ is available in gcc versions 3.4 and newer,
++ while the typeof feature has been available since 2.7 at least. */
++# if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
++# define ignore_value(x) ((void) (x))
++# else
++# define ignore_value(x) (({ __typeof__ (x) __x = (x); (void) __x; }))
++# endif
++
++/* ignore_value works for scalars, pointers and aggregates;
++ deprecate ignore_ptr. */
++static inline void ATTRIBUTE_DEPRECATED
++ignore_ptr (void *p) { (void) p; } /* deprecated: use ignore_value */
++
++#endif