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

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

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));

  	mutex_lock(&module_mutex);
  	list_for_each_entry(use, &mod->target_list, target_list) {
-- 
1.7.1.rc1.21.gf3bd6