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Diffstat (limited to 'gnulib/lib/ignore-value.h')
m--------- | gnulib | 0 | ||||
-rw-r--r-- | gnulib/lib/ignore-value.h | 62 |
2 files changed, 62 insertions, 0 deletions
diff --git a/gnulib b/gnulib deleted file mode 160000 -Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1 diff --git a/gnulib/lib/ignore-value.h b/gnulib/lib/ignore-value.h new file mode 100644 index 0000000..f021a1a --- /dev/null +++ b/gnulib/lib/ignore-value.h @@ -0,0 +1,62 @@ +/* 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 _GL_ATTRIBUTE_DEPRECATED +/* The __attribute__((__deprecated__)) feature + is available in gcc versions 3.1 and newer. */ +# if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 1) +# define _GL_ATTRIBUTE_DEPRECATED /* empty */ +# else +# define _GL_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 _GL_ATTRIBUTE_DEPRECATED +ignore_ptr (void *p) { (void) p; } /* deprecated: use ignore_value */ + +#endif |