Re: [PATCH gnulib 4/4] RFC stat: x86_64 mingw64 #define stat as _stat64.

[Marc-André Lureau]

On Sat, Jan 28, 2012 at 12:49 PM, Bruno Haible <address@hidden> wrote:
> If you have to make such a change to lib/tempname.c, the chances are high
> that gnulib users also will have to adapt their programs. Which would be
> against the spirit of gnulib: Packages that use gnulib should use the
> POSIX or glibc API.

Indeed, I am not satisifed with the proposed solution, but I feel like
there is a limitation, and we can't easily replace both stat() and
struct stat.

> What is the problem in the first place? Which warning or error did you
> get? Please also show snippets from the .h files with relevant information.

stat.c: In function 'rpl_stat':
stat.c:67:3: warning: passing argument 2 of 'orig_stat' from
incompatible pointer type [enabled by default]
stat.c:31:1: note: expected 'struct _stat64 *' but argument is of type
'struct stat *'
stat.c:113:11: warning: passing argument 2 of 'orig_stat' from
incompatible pointer type [enabled by default]
stat.c:31:1: note: expected 'struct _stat64 *' but argument is of type
'struct stat *'

And the ./m4/sys_stat_h.m4 included between orig_stat() and rpl_stat():

/* We can't use the object-like #define stat rpl_stat, because of
   struct stat.  This means that rpl_stat will not be used if the user
   does (stat)(a,b).  Oh well.  */
#  undef stat
#  ifdef _LARGE_FILES
    /* With _LARGE_FILES defined, AIX (only) defines stat to stat64,
       so we have to replace stat64() instead of stat(). */
#   define stat stat64
#   undef stat64
#   define stat64(name, st) rpl_stat (name, st)
#  else /* !_LARGE_FILES */
#   define stat(name, st) rpl_stat (name, st)
#  endif /* !_LARGE_FILES */

Apparently, gnulib would like to replace stat() with rpl_stat()
because of some incompatibilites, but it has to give up on previous
#define stat _stat64 on mingw64. This is the cause of the warnings.
Tbh, I have no idea how we can achieve to replace both struct "stat"
and "stat()" without introducing new struct or function name.

>> #define stat as _stat64
>
> I don't see such a #define in my copy of mingw64. Where do you see it?

https://mingw-w64.svn.sourceforge.net/svnroot/mingw-w64/trunk/mingw-w64-headers/crt/sys/stat.h

-- 
Marc-André Lureau