Re: [PATCH 5/6]kernel:module.c variable 'nowarn' set but not used

["Justin P. Mattock" <justinmattock@gmail.com>]

On 06/19/2010 01:23 PM, Geert Uytterhoeven wrote:
> On Sat, Jun 19, 2010 at 22:10, Justin P. Mattock
> <justinmattock@gmail.com>  wrote:
>> On 06/19/2010 12:45 PM, Geert Uytterhoeven wrote:
>>>
>>> On Sat, Jun 19, 2010 at 21:10, Justin P. Mattock
>>> <justinmattock@gmail.com>    wrote:
>>>>
>>>> On 06/19/2010 01:08 AM, Geert Uytterhoeven wrote:
>>>>>
>>>>> On Sat, Jun 19, 2010 at 07:04, Justin P. Mattock
>>>>> <justinmattock@gmail.com>      wrote:
>>>>>>>
>>>>>>> Also wrong, you removed the creation of the links in sysfs.
>>>>>>>
>>>>>>> The assignment to nowarn was there to avoid another compiler warning,
>>>>>>> as sysfs_create_link() is marked __must_check.
>>>>>>
>>>>>> I also went back to this one and made the following changes.. let me
>>>>>> know
>>>>>> if
>>>>>> it's wrong etc..
>>>>>>
>>>>>>   From 4f45beed80627d2bb32fb021bb6d22d88089557b Mon Sep 17 00:00:00 2001
>>>>>> From: Justin P. Mattock<justinmattock@gmail.com>
>>>>>> Date: Fri, 18 Jun 2010 22:01:07 -0700
>>>>>> Subject: [PATCH 5/5] module.c
>>>>>>   Signed-off-by: Justin P. Mattock<justinmattock@gmail.com>
>>>>>>
>>>>>> ---
>>>>>>   kernel/module.c |    3 +--
>>>>>>   1 files changed, 1 insertions(+), 2 deletions(-)
>>>>>>
>>>>>> diff --git a/kernel/module.c b/kernel/module.c
>>>>>> index 8c6b428..48fc5c8 100644
>>>>>> --- a/kernel/module.c
>>>>>> +++ b/kernel/module.c
>>>>>> @@ -1340,11 +1340,10 @@ static void add_usage_links(struct module *mod)
>>>>>>   {
>>>>>>   #ifdef CONFIG_MODULE_UNLOAD
>>>>>>         struct module_use *use;
>>>>>> -       int nowarn;
>>>>>>
>>>>>>         mutex_lock(&module_mutex);
>>>>>>         list_for_each_entry(use,&mod->target_list, target_list) {
>>>>>> -               nowarn = sysfs_create_link(use->target->holders_dir,
>>>>>> +               sysfs_create_link(use->target->holders_dir,
>>>>>>                                            &mod->mkobj.kobj, mod->name);
>>>>>>         }
>>>>>>         mutex_unlock(&module_mutex);
>>>>>> --
>>>>>> 1.7.1.rc1.21.gf3bd6
>>>>>>
>>>>>> if it looks good, then I can resend it out.
>>>>>
>>>>> Have you compile-tested this?
>>>>> As sysfs_create_link() is marked __must_check, that will cause another
>>>>> compiler
>>>>> warning, but only if CONFIG_SYSFS=y.
>>>>>
>>>>> Perhaps you can just mark the nowarn variable __unused?
>>>>
>>>>
>>>> o.k. this builds cleanly without a warning, but is it the right thing
>>>> todo?
>>>> i.g. rather leave the warning message there and file a bug than just
>>>> silence
>>>> the issue. Anyways here is what I have:
>>>>
>>>>   From edbeb2b1ee051218f9e5b93fcb8bbdbf1119a6e4 Mon Sep 17 00:00:00 2001
>>>> From: Justin P. Mattock<justinmattock@gmail.com>
>>>> Date: Sat, 19 Jun 2010 12:07:32 -0700
>>>> Subject: [PATCH 5/5] module.c
>>>>   Signed-off-by: Justin P. Mattock<justinmattock@gmail.com>
>>>>
>>>> ---
>>>>   kernel/module.c |    2 +-
>>>>   1 files changed, 1 insertions(+), 1 deletions(-)
>>>>
>>>> diff --git a/kernel/module.c b/kernel/module.c
>>>> index 8c6b428..765bac5 100644
>>>> --- a/kernel/module.c
>>>> +++ b/kernel/module.c
>>>> @@ -1340,7 +1340,7 @@ static void add_usage_links(struct module *mod)
>>>>   {
>>>>   #ifdef CONFIG_MODULE_UNLOAD
>>>>         struct module_use *use;
>>>> -       int nowarn;
>>>> +       int nowarn __attribute__((unused));
>>>
>>> The `__attribute__((unused))' should be `__used'.
>>>
>>
>> I'm confused now. how should I write that out?
>> (google is not giving me vary many examples on this)
>
> Sorry, I misrememberd there was a #define for it, and could find only __used.
> But on closer look, the `__attribute__((unused)` is correct.
>

alright!! then I'll resend this with the above change.

Thanks for looking at this!!

Justin P. Mattock