Re: [PATCH] net: tulip: avoid unused variable warning

From: Simon Horman
Date: Thu Mar 13 2025 - 06:55:35 EST


On Wed, Mar 12, 2025 at 03:08:35PM +0100, Helge Deller wrote:
> On 3/12/25 14:14, Simon Horman wrote:
> > On Sun, Mar 09, 2025 at 10:42:38PM +0100, deller@xxxxxxxxxx wrote:
> > > From: Helge Deller <deller@xxxxxx>
> > >
> > > When compiling with W=1 and CONFIG_TULIP_MWI=n one gets this warning:
> > > drivers/net/ethernet/dec/tulip/tulip_core.c: In function ‘tulip_init_one’:
> > > drivers/net/ethernet/dec/tulip/tulip_core.c:1309:22: warning: variable ‘force_csr0’ set but not used
> > >
> > > Avoid it by annotating the variable __maybe_unused, which seems to be
> > > the easiest solution.
> > >
> > > Signed-off-by: Helge Deller <deller@xxxxxx>
> >
> > Hi Helge,
> >
> > A few thoughts on this:
>
> Hi Simon,
>
> Thanks for following up on this!
>
> > Firstly, thanks for your patch, which I agree addresses the problem you
> > have described.
> >
> > However, AFAIK, this is a rather old driver and I'm not sure that
> > addressing somewhat cosmetic problems are worth the churn they cause:
> > maybe it's best to leave it be.
>
> Well, the only reason why I sent this patch is, because some people
> are interested to get a Linux kernel build without any warnings when "W=1"
> option is enabled.
> This code in the tulip driver is one of the last 10 places in the kernel where
> I see a warning at all, so I think it's worth fixing it, although it's just
> cosmetic.
>
>
> > But if we do want to fix this problem, I do wonder if the following
> > solution, which leverages IS_ENABLED, is somehow nicer as
> > it slightly reduces the amount of conditionally compiled code,
> > thus increasing compile test coverage.
>
> Full Ack from my side!
> I wanted to keep my patch small, but your proposed patch is the better one.
>
> I did not compile-test it, but if it builds you may add my:
> Acked-by: Helge Deller <deller@xxxxxx>

Thanks, I posted v2 here:

https://lore.kernel.org/netdev/20250313-tulip-w1-v2-1-2ac0d3d909f9@xxxxxxxxxx/T/#u