[vlc-devel] [PATCH 7/8] vlc_plugin.h: Cast the deactivate function pointer

[Romain Vimont]

On Thu, Dec 03, 2020 at 06:39:47PM +0200, Rémi Denis-Courmont wrote:
> Le torstaina 3. joulukuuta 2020, 17.16.20 EET Hugo Beauzée-Luyssen a écrit :
> > Instead of initializing a function pointer using a compound literal,
> > which might not compile in C++
> > ---
> >  include/vlc_plugin.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/include/vlc_plugin.h b/include/vlc_plugin.h
> > index 63f0b3ac08..7a68c953e3 100644
> > --- a/include/vlc_plugin.h
> > +++ b/include/vlc_plugin.h
> > @@ -313,7 +313,7 @@ VLC_METADATA_EXPORTS
> >  #define set_callbacks( activate, deactivate ) \
> >      set_callback(activate) \
> >      if (vlc_module_set(VLC_MODULE_CB_CLOSE, #deactivate, \
> > -                       (void (*)(vlc_object_t *)){ deactivate })) \
> > +                       (void (*)(vlc_object_t *))( deactivate ))) \
> 
> The current code will warn if the conversion makes no sense.
> This won't.

It seems this does warn. For example, if we cast to a wrong function type
instead:

   if (vlc_module_set(VLC_MODULE_CB_CLOSE, #deactivate, \
                      (void (*)(int))( deactivate ))) \

../../include/vlc_plugin.h:316:24: warning: cast between incompatible function types from ‘void (*)(vlc_object_t *)’ to ‘void (*)(int)’ [-Wcast-function-type]
  316 |                        (void (*)(int))( deactivate ))) \