Re: [PATCH 08/30] net: wireless: ath: carl9170: Mark 'ar9170_qmap' as __maybe_unused

[Lee Jones]

On Fri, 14 Aug 2020, Christian Lamparter wrote:

> On 2020-08-14 13:39, Lee Jones wrote:
> > 'ar9170_qmap' is used in some source files which include carl9170.h,
> > but not all of them.  Mark it as __maybe_unused to show that this is
> > not only okay, it's expected.
> > 
> > Fixes the following W=1 kernel build warning(s)
> 
> Is this W=1 really a "must" requirement? I find it strange having

Clean W=1 warnings is the dream, yes.

I would have thought most Maintainers would be on-board with this.

The ones I've worked with thus far have certainly been thankful.  Many
had this on their own TODO lists.

> __maybe_unused in header files as this "suggests" that the
> definition is redundant.

Not true.

If it were redundant then we would remove the line entirely.

> >   from drivers/net/wireless/ath/carl9170/carl9170.h:57,
> >   In file included from drivers/net/wireless/ath/carl9170/carl9170.h:57,
> >   drivers/net/wireless/ath/carl9170/carl9170.h:71:17: warning: ‘ar9170_qmap’ defined but not used [-Wunused-const-variable=]
> > 
> > Cc: Christian Lamparter <chunkeey@xxxxxxxxxxxxxx>
> > Cc: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> > Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> > Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
> > Cc: linux-wireless@xxxxxxxxxxxxxxx
> > Cc: netdev@xxxxxxxxxxxxxxx
> > Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
> > ---
> >   drivers/net/wireless/ath/carl9170/carl9170.h | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/wireless/ath/carl9170/carl9170.h b/drivers/net/wireless/ath/carl9170/carl9170.h
> > index 237d0cda1bcb0..9d86253081bce 100644
> > --- a/drivers/net/wireless/ath/carl9170/carl9170.h
> > +++ b/drivers/net/wireless/ath/carl9170/carl9170.h
> > @@ -68,7 +68,7 @@
> >   #define PAYLOAD_MAX	(CARL9170_MAX_CMD_LEN / 4 - 1)
> > -static const u8 ar9170_qmap[__AR9170_NUM_TXQ] = { 3, 2, 1, 0 };
> > +static const u8 __maybe_unused ar9170_qmap[__AR9170_NUM_TXQ] = { 3, 2, 1, 0 };
> >   #define CARL9170_MAX_RX_BUFFER_SIZE		8192
> > 
> 

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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