[Bug c++/108203] New: Format string checking with __USE_MINGW_ANSI_STDIO

[Bug c++/108203] New: Format string checking with __USE_MINGW_ANSI_STDIO

[nightstrike at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108203

            Bug ID: 108203
           Summary: Format string checking with __USE_MINGW_ANSI_STDIO
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nightstrike at gmail dot com
  Target Milestone: ---

Circa v4.5, some mingw-w64 users discovered an issue with printf functions and
g++.  Addressing this resulted in a kludge on the mingw-w64 headers side, but
this should have been documented here so that we can remove the kludge and have
a better coordination between projects.

Original mail thread describing the problem:
https://sourceforge.net/p/mingw-w64/mailman/mingw-w64-public/thread/4F05E61C.6010506%40t-online.de/#msg28632591


Bug report that came from it:
https://sourceforge.net/p/mingw-w64/bugs/292/


Header change from fixing the bug report:
https://sourceforge.net/p/mingw-w64/mingw-w64/ci/280b5f973e/


This commit might potentially be related:
https://sourceforge.net/p/mingw-w64/mingw-w64/ci/1ed6dcc2a19c1aeac5dd4e6530af899fd8d95dbb/

+/* Override __builtin_printf-routines ... Kludge for libstdc++ ...*/
+#define __builtin_vsnprintf __mingw_vsnprintf
+#define __builtin_vsprintf __mingw_vsprintf


I hope with this PR, we can better coordinate and make both sides better :)

[Bug c++/108203] Format string checking with __USE_MINGW_ANSI_STDIO

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108203

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=95130

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I suspect this is a dup of bug 95130

[Bug c++/108203] Format string checking with __USE_MINGW_ANSI_STDIO

[lh_mouse at 126 dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108203

--- Comment #2 from LIU Hao <lh_mouse at 126 dot com> ---
(In reply to nightstrike from comment #0)
> Bug report that came from it:
> https://sourceforge.net/p/mingw-w64/bugs/292/
> 

I think this should be no longer the case. Two years ago I submitted a patch
that made the `ms_printf` attribute accept `%lld`, so there is now a universal
modifier for `long long`.

The issue here looks like that `printf` , which is a 'well known' function to
GCC, has a pre-defined attribute. If a new `*_printf` attribute is declared, it
gets both, as pointed out by Andrew Pinski.