Re: [PATCH] static_call: Fix unused variable warning

From: Guenter Roeck
Date: Wed Apr 21 2021 - 21:24:22 EST


On 4/21/21 5:41 PM, Steven Rostedt wrote:
>
> Second patch with the exact same update. Perhaps we should take one
> before we get more of them ;-)
>
> https://lore.kernel.org/lkml/20210416194300.3952208-1-cmllamas@xxxxxxxxxx/
>

Sorry, I missed the other one.

Guenter

> -- Steve
>
>
> On Wed, 21 Apr 2021 17:33:34 -0700
> Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
>
>> If CONFIG_MODULES=n, the following build warning is reported.
>>
>> kernel/static_call.c: In function ‘__static_call_update’:
>> kernel/static_call.c:153:18: warning: unused variable ‘mod’
>>
>> Mark the variable as __maybe_unused to fix the problem.
>>
>> Fixes: 9183c3f9ed71 ("static_call: Add inline static call infrastructure")
>> Reported-by: Zach Reizner <zachr@xxxxxxxxxx>
>> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
>> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
>> ---
>> kernel/static_call.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/kernel/static_call.c b/kernel/static_call.c
>> index 2c5950b0b90e..8211a34251f8 100644
>> --- a/kernel/static_call.c
>> +++ b/kernel/static_call.c
>> @@ -150,7 +150,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
>>
>> for (site_mod = &first; site_mod; site_mod = site_mod->next) {
>> bool init = system_state < SYSTEM_RUNNING;
>> - struct module *mod = site_mod->mod;
>> + struct module __maybe_unused *mod = site_mod->mod;
>>
>> if (!site_mod->sites) {
>> /*
>