Re: [PATCH v2] can: build proc support only if CONFIG_PROC_FS is activated

[Oliver Hartkopp <socketcan@hartkopp.net>]

On 06/18/2016 11:36 AM, Alexander Aring wrote:
>
> Hi,
>
> On 06/18/2016 10:57 AM, Oliver Hartkopp wrote:
>> Hi Alexander,
>>
>> there's a procfs dependency of the CAN_BCM too.
>>
>> On 06/17/2016 02:08 PM, Marc Kleine-Budde wrote:
>>> From: Alexander Aring <aar@pengutronix.de>
>>>
>>> When building can subsystem with CONFIG_PROC_FS=n I detected some unused
>>> variables warning by using proc functions.
>>
>> Did you miss to switch on CAN_BCM when doing a CONFIG_PROC_FS disabled test?
>>
>
> I detected the unused variable warnings while running randconfig, the
> first time I didn't saw the CAN_BCM but the second time (yet another
> randconfig) I saw CAN_BCM.
>
> net/can/bcm.c:235:37: warning: ‘bcm_proc_fops’ defined but not used
> [-Wunused-const-variable=]
>   static const struct file_operations bcm_proc_fops = {
>
>> Or is the procfs subsystem that intelligent that it just disables the functionality so that the users (e.g. in bcm.c) don't need to care about CONFIG_PROC_FS.
>>
>
> It is such intelligent, but you have no static inline no-op's for
> functions which returns a pointer. It's:
>
> #define proc_fs_foobar NULL
>
> will be used and this occurs warnings while compiling. In case of
> can-proc you really don't need to link against it if CONFIG_PROC_FS
> isn't set - will turn off the warnings and compiles faster.
>
> The CAN_BCM should be fixed as well, most subsystem puts ifdefs arounds
> the proc functionality if it's not well outsourced like can-proc.c.
>
> Who will send a patch now?

Feel free to sent a patch!
You detected the issue and as it turns out that you are capable to 
create patches :-)

I would appreciate to see you as author then.

Thanks,
Oliver

>
> - Alex
>