Re: [PATCH] net: ethernet: mscc: fix missing brace warning for old compilers

[David Sterba]

On Mon, Nov 02, 2020 at 01:56:55PM +0000, Vladimir Oltean wrote:
> On Mon, Nov 02, 2020 at 09:41:36PM +0800, Pujin Shi wrote:
> > For older versions of gcc, the array = {0}; will cause warnings:
> > 
> > drivers/net/ethernet/mscc/ocelot_vcap.c: In function 'is1_entry_set':
> > drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: missing braces around initializer [-Wmissing-braces]
> >     struct ocelot_vcap_u16 etype = {0};
> >            ^
> > drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: (near initialization for 'etype.value') [-Wmissing-braces]
> > 
> > 1 warnings generated
> > 
> > Fixes: 75944fda1dfe ("net: mscc: ocelot: offload ingress skbedit and vlan actions to VCAP IS1")
> > Signed-off-by: Pujin Shi <shipujin.t@xxxxxxxxx>
> > ---
> >  drivers/net/ethernet/mscc/ocelot_vcap.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/ethernet/mscc/ocelot_vcap.c b/drivers/net/ethernet/mscc/ocelot_vcap.c
> > index d8c778ee6f1b..b96eab4583e7 100644
> > --- a/drivers/net/ethernet/mscc/ocelot_vcap.c
> > +++ b/drivers/net/ethernet/mscc/ocelot_vcap.c
> > @@ -752,7 +752,7 @@ static void is1_entry_set(struct ocelot *ocelot, int ix,
> >  					     dport);
> >  		} else {
> >  			/* IPv4 "other" frame */
> > -			struct ocelot_vcap_u16 etype = {0};
> > +			struct ocelot_vcap_u16 etype = {};
> >  
> >  			/* Overloaded field */
> >  			etype.value[0] = proto.value[0];
> 
> Sorry, I don't understand what the problem is, or why your patch fixes
> it. What version of gcc are you testing with?

Nothing wrong and { 0 } is the right initializer, the reports must be
from some ancient gcc but we weren't told which one either.

https://lore.kernel.org/linux-btrfs/fbddb15a-6e46-3f21-23ba-b18f66e3448a@xxxxxxxx/