Re: [PATCH] rcu: remove unused variable in boot_cpu_state_init

From: Arnd Bergmann
Date: Wed Jun 21 2017 - 18:16:01 EST


On Thu, Jun 22, 2017 at 12:10 AM, Paul E. McKenney
<paulmck@xxxxxxxxxxxxxxxxxx> wrote:
> On Wed, Jun 21, 2017 at 11:57:28PM +0200, Arnd Bergmann wrote:
>> Without CONFIG_SMP, we get a harmless warning about
>> an unused variable:
>>
>> kernel/cpu.c: In function 'boot_cpu_state_init':
>> kernel/cpu.c:1778:6: error: unused variable 'cpu' [-Werror=unused-variable]
>>
>> This reworks the function to have the declaration inside
>> of the #ifdef.
>>
>> Fixes: faeb334286b7 ("rcu: Migrate callbacks earlier in the CPU-offline timeline")
>> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
>
> I simply added a __maybe_unused in 6441c656acde ("rcu: Migrate callbacks
> earlier in the CPU-offline timeline") in my -rcu tree. However, your
> approach does have the advantage of complaining if the code using that
> variable is removed.
>
> So, would you be OK with my folding your approach into my commit with
> attribution?

Sure, that's always best.

Arnd