warning in omap_connector

[Laurent Pinchart]

Hi Dave,

On Thu, Jul 23, 2020 at 02:28:22PM +1000, Dave Airlie wrote:
> I think I'm still seeing this.

I'm sorry, I've let it slip through the cracks :-S Ville as beaten me at
submitting a patch (kiitos paljon Ville).

> On Wed, 1 Jul 2020 at 01:08, Ville Syrjälä wrote:
> > On Tue, Jun 30, 2020 at 05:41:32PM +0300, Laurent Pinchart wrote:
> > > On Tue, Jun 30, 2020 at 05:39:02PM +0300, Ville Syrjälä wrote:
> > > > On Tue, Jun 30, 2020 at 10:19:23AM -0400, Alex Deucher wrote:
> > > > > On Tue, Jun 30, 2020 at 10:15 AM Ville Syrjälä wrote:
> > > > > >
> > > > > > On Tue, Jun 30, 2020 at 04:33:37PM +1000, Dave Airlie wrote:
> > > > > > > Hey Laurent,
> > > > > > >
> > > > > > > I merged drm-misc-next and noticed this, I'm not sure if it's
> > > > > > > collateral damage from something else changing or I've just missed it
> > > > > > > previously. 32-bit arm build.
> > > > > > >
> > > > > > >
> > > > > > > /home/airlied/devel/kernel/dim/src/drivers/gpu/drm/omapdrm/omap_connector.c:
> > > > > > > In function ‘omap_connector_mode_valid’:
> > > > > > > /home/airlied/devel/kernel/dim/src/drivers/gpu/drm/omapdrm/omap_connector.c:92:9:
> > > > > > > warning: braces around scalar initializer
> > > > > > >   struct drm_display_mode new_mode = { { 0 } };
> > > > > >
> > > > > > Probably fallout from my drm_display_mode shrinkage.
> > > > > >
> > > > > > Going to repeat my usual "just use {} when zero initializing
> > > > > > structs" recommendation. Avoids these stupid warnings, and IMO
> > > > > > also conveys the meaning better since there's no ambiguity
> > > > > > between zero initializing the whole struct vs. zero initializing
> > > > > > just the first member.
> > > > >
> > > > > IIRC, LLVM and GCC treat these slightly differently.  We've generally
> > > > > just moved to using memset to avoid different compiler complaints when
> > > > > using these.
> > > >
> > > > I don't particularly like memset() since the requirement to
> > > > pass the size just adds another way to screw things up. The
> > > > usual 'sizeof(*thing)' makes that slightly less of an issue,
> > > > but I've noticed that people often don't use that.
> > > >
> > > > Another issue with memset() is that you then can end up with
> > > > a block of seemingly random collection of memsets()s between
> > > > the variable declarations and the rest of the code. I suppose
> > > > if we could declare variables anywhere we could always keep
> > > > the two together so it wouldn't look so weird, but can't do
> > > > that for the time being. And even with that it would still
> > > > lead to less succinct code, which I generally dislike.
> > >
> > > I'd prefer { } over memset, assuming clang and gcc would treat it
> > > correctly. Ville, I can submit a patch, unless you want to do it
> > > yourself as it's a fallout from drm_display_mode shrinkage ;-)
> > > (seriously speaking, not pushing you, I just want to avoid duplicating
> > > work).
> >
> > Go ahead if you want to. I'm in middle of a bigger rebase atm
> > so can't do it right this minute myself.

-- 
Regards,

Laurent Pinchart