Re: [PATCH] fix calls to request_module()

["Nguyen Anh Quynh" <aquynh@gmail.com>]

On Thu, Dec 11, 2008 at 1:14 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Thu, 11 Dec 2008 04:01:18 +0000 Al Viro <viro@ZenIV.linux.org.uk> wrote:
>
>> On Thu, Dec 11, 2008 at 12:35:21PM +0900, Nguyen Anh Quynh wrote:
>> > Hi,
>> >
>> > The request_module() function should always have the 1st param as a
>> > format argument. So for example, request_module("i2c-powermac") should
>> > be called as request_module("%s", "i2c-powermac"). Otherwise, new gcc
>> > like gcc 4.3.2 on Ubuntu 8.10 would spit out a lot of warnings. This
>> > patch fixes them all in linus-git tree.
>>
>> ... and it doesn't address the underlying problems at all.  A string literal
>> without a single % in it is a perfectly sane and valid format.  _Why_ are
>> we getting these warning?
>
> extern int request_module(const char * name, ...) __attribute__ ((format (printf, 1, 2)));
>

Sorry that after the mail of Viro, I checked again by recover a code
and recompile, but got no warning. But actually that code should not
be compiled at all.

So I checked again by fixing the code that should be compiled
(sound/core/sound.c), and can confirm that without the patch we got
warning like below:

sound/core/sound.c: In function 'snd_request_other':
sound/core/sound.c:91: warning: format not a string literal and no
format arguments

And with the patch, the warnings are all gone.

So Andrew, please consider taking the patch.

Thanks,
Quynh