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authorLudovic Courtès <ludo@gnu.org>2009-11-15 20:16:40 +0100
committerLudovic Courtès <ludo@gnu.org>2009-11-16 09:23:46 +0100
commit8912421cf3829a4fd65877fd1255125c191f6f89 (patch)
tree6b89fecf0738a1f80792bbe7453730f7882f1d54 /lib/ignore-value.h
parent3fe87cf7aff396d7bd993aa009f48eb8afd6c1cd (diff)
downloadguile-8912421cf3829a4fd65877fd1255125c191f6f89.tar.gz
Use Gnulib's `inet_ntop' and `inet_pton' modules.
* m4/gnulib-cache.m4: Add `inet_ntop' and `inet_pton'. * configure.ac: Don't check for `inet_ntop' and `inet_pton'. * libguile/socket.c (scm_inet_pton, scm_inet_ntop): Compile regardless of `HAVE_INET_PTON' and `HAVE_INET_NTOP' respectively. * libguile/filesys.c: Use <stdlib.h> instead of <canonicalize.h>.
Diffstat (limited to 'lib/ignore-value.h')
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diff --git a/lib/ignore-value.h b/lib/ignore-value.h
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+/* ignore a function return without a compiler warning
+
+ Copyright (C) 2008-2009 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. */
+
+/* Use these functions 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". */
+
+static inline void ignore_value (int i) { (void) i; }
+static inline void ignore_ptr (void* p) { (void) p; }
+/* FIXME: what about aggregate types? */