On 03/20/2011 02:26 PM, Bruno Haible wrote: > Yes, in this case, where the override only affects function declaration > attributes, that should be OK.
Thanks, that simplifies thingst. I pushed the following revised patch, which incorporates your other suggestions. For now I'm holding off on fwrite_unlocked so that we can see how well fwrite works. stdio: don't require ignore_value around fwrite This patch works around libc bug 11959 <http://sources.redhat.com/bugzilla/show_bug.cgi?id=11959>. Without this patch, applications must often write ignore_value (fwrite (...)) even though the ignore_value is not helpful here. It's common to write many objects, using fwrite/printf/etc., and then use ferror to detect output error. I considered making this patch optional, but decided against it, because libc is obviously being inconsistent here: there is no reason libc should insist that user code must inspect fwrite return's value without also insisting that it inspect printf's, putchar's, etc. If user code wants to have a strict style where all these functions' values are checked (so that ferror need not be checked), we could add support for that style in a new gnulib module, but in the meantime it's better to be consistent and to support common usage. * lib/stdio.in.h (rpl_fwrite): Define this wrapper around fwrite, to work around libc bug 11959, if __USE_FORTIFY_LEVEL indicates that we are compiling in checking mode, and if not C++, and if not already wrapping fwrite for some other reason. (fwrite): #define to rpl_fwrite if the latter is defined. diff --git a/lib/stdio.in.h b/lib/stdio.in.h index b5083d1..816c9f2 100644 --- a/lib/stdio.in.h +++ b/lib/stdio.in.h @@ -496,6 +496,23 @@ _GL_CXXALIAS_RPL (fwrite, size_t, # else _GL_CXXALIAS_SYS (fwrite, size_t, (const void *ptr, size_t s, size_t n, FILE *stream)); + +/* Work around glibc bug 11959 + <http://sources.redhat.com/bugzilla/show_bug.cgi?id=11959>, + which sometimes causes an unwanted diagnostic for fwrite calls. + This affects only function declaration attributes, so it's not + needed for C++. */ +# if !defined __cplusplus && 0 < __USE_FORTIFY_LEVEL +static inline size_t _GL_ARG_NONNULL ((1, 4)) +rpl_fwrite (const void *ptr, size_t s, size_t n, FILE *stream) +{ + size_t r = fwrite (ptr, s, n, stream); + (void) r; + return r; +} +# undef fwrite +# define fwrite rpl_fwrite +# endif # endif _GL_CXXALIASWARN (fwrite); #endif
