Re: [PATCH 07/27] Replace GCC_FMT_ATTR with G_GNUC_PRINTF

[Marc-André Lureau <marcandre.lureau@xxxxxxxxxx>]

Hi

On Wed, Mar 16, 2022 at 5:30 PM Daniel P. Berrangé <berrange@xxxxxxxxxx> wrote:
>
> On Wed, Mar 16, 2022 at 01:52:48PM +0400, marcandre.lureau@xxxxxxxxxx wrote:
> > diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h
> > index 3baa5e3790f7..f2bd050e3b9a 100644
> > --- a/include/qemu/compiler.h
> > +++ b/include/qemu/compiler.h
> > @@ -79,19 +79,12 @@
> >  #define QEMU_BUILD_BUG_ON_ZERO(x) (sizeof(QEMU_BUILD_BUG_ON_STRUCT(x)) - \
> >                                     sizeof(QEMU_BUILD_BUG_ON_STRUCT(x)))
> >
> > -#if defined(__clang__)
> > -/* clang doesn't support gnu_printf, so use printf. */
> > -# define GCC_FMT_ATTR(n, m) __attribute__((format(printf, n, m)))
> > -#else
> > -/* Use gnu_printf (qemu uses standard format strings). */
> > -# define GCC_FMT_ATTR(n, m) __attribute__((format(gnu_printf, n, m)))
> > -# if defined(_WIN32)
> > +#if !defined(__clang__) && defined(_WIN32)
> >  /*
> >   * Map __printf__ to __gnu_printf__ because we want standard format 
> > strings even
> >   * when MinGW or GLib include files use __printf__.
> >   */
> > -#  define __printf__ __gnu_printf__
> > -# endif
> > +# define __printf__ __gnu_printf__
> >  #endif
>
> I'm not convinced we shold have this remaining define, even
> before your patch.
>
> For code we've implemented, we should have used __gnu_printf__
> already if we know it uses GNU format on Windows.
>
> For code in GLib, its header file uses __gnu_printf__ for anything
> that relies on its portable printf replacement, which is basically
> everything in GLib.
>
> For anything else we should honour whatever they declare, and not
> assume their impl is the GNU one.
>
>
> I guess it is easy enough to validate by deleting this and seeing
> if we get any warnings from the mingw CI jobs about printf/gnu_printf
> mismatch.

Please comment on that thread:
https://patchew.org/QEMU/20220224183701.608720-1-marcandre.lureau@xxxxxxxxxx/20220224183701.608720-6-marcandre.lureau@xxxxxxxxxx/

>
> With regards,
> Daniel
> --
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>