Re: [PATCH] ata: pata_cs5535: Fix W=1 warnings

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 6/28/22 19:05, Sergey Shtylyov wrote:
> Hello!
> 
> On 6/28/22 11:59 AM, Damien Le Moal wrote:
> [...]
>>> x86_64 allmodconfig build with W=1 gives these warnings:
>>>
>>> drivers/ata/pata_cs5535.c: In function ‘cs5535_set_piomode’:
>>> drivers/ata/pata_cs5535.c:93:11: error: variable ‘dummy’ set but not used [-Werror=unused-but-set-variable]
>>>   u32 reg, dummy;
>>>            ^~~~~
>>> drivers/ata/pata_cs5535.c: In function ‘cs5535_set_dmamode’:
>>> drivers/ata/pata_cs5535.c:132:11: error: variable ‘dummy’ set but not used [-Werror=unused-but-set-variable]
>>>   u32 reg, dummy;
>>>            ^~~~~
>>> cc1: all warnings being treated as errors
>>>
>>> Mark variables 'dummy' as "maybe unused" to satisfy when rdmsr() is
>>> stubbed, which is the same as what we already do in pata_cs5536.c .
>>>
>>> Signed-off-by: John Garry <john.garry@huawei.com>
> 
> 
> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
> 
>> Looks good, but I wonder why I am not getting this warning. I always do
>> W=1 and C=1 builds. I tried allmodconfig now and I am not getting the
>> warning...
> 
>    I can confirm the (fatal) warnings with RedHat gcc 10.3.1... but somehow they only
> occur on x86_64 with allmodconfig indeed (which is strange)...

Compiling on x86_64 with allmodconfig with gcc 12 and sparse-0.6.4-2
(Fedora 36) does not give the warning... Weird.

> 
> [...]
> 
> MBR, Sergey
> 


-- 
Damien Le Moal
Western Digital Research