linux-kernel - Re: [PATCH] drivers/staging/lustre: Coding-guideline: Missing a blank line after declarations

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 4 Apr 2017 15:35:31 +0530
From:   Pushkar Jambhlekar <pushkar.iit@...il.com>
To:     Dan Carpenter <dan.carpenter@...cle.com>
Cc:     Oleg Drokin <oleg.drokin@...el.com>,
        Andreas Dilger <andreas.dilger@...el.com>,
        James Simmons <jsimmons@...radead.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "John L. Hammond" <john.hammond@...el.com>,
        Al Viro <viro@...iv.linux.org.uk>,
        Lai Siyao <lai.siyao@...el.com>,
        James Nunez <james.a.nunez@...el.com>,
        Andrew Perepechko <andrew.perepechko@...gate.com>,
        wang di <di.wang@...el.com>,
        Bob Glossman <bob.glossman@...el.com>,
        Andreas Gruenbacher <agruenba@...hat.com>,
        Jinshan Xiong <jinshan.xiong@...el.com>,
        Bobi Jam <bobijam@...mail.com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Henri Doreau <henri.doreau@....fr>,
        Prakash Surya <surya1@...l.gov>,
        Emoly Liu <emoly.liu@...el.com>,
        Dmitry Eremin <dmitry.eremin@...el.com>,
        Johann Lombardi <johann.lombardi@...el.com>,
        "open list:STAGING SUBSYSTEM" <devel@...verdev.osuosl.org>,
        linux-kernel <linux-kernel@...r.kernel.org>,
        lustre-devel@...ts.lustre.org
Subject: Re: [PATCH] drivers/staging/lustre: Coding-guideline: Missing a blank
 line after declarations

((void)sizeof !!(exp)) => I believe it is for compiler to unflag
"unused variable" warning.

On Tue, Apr 4, 2017 at 3:08 PM, Dan Carpenter <dan.carpenter@...cle.com> wrote:
> On Tue, Apr 04, 2017 at 02:45:26PM +0530, Pushkar Jambhlekar wrote:
>> diff --git a/drivers/staging/lustre/lustre/obdclass/cl_page.c b/drivers/staging/lustre/lustre/obdclass/cl_page.c
>> index cd9a40c..71fcc4c 100644
>> --- a/drivers/staging/lustre/lustre/obdclass/cl_page.c
>> +++ b/drivers/staging/lustre/lustre/obdclass/cl_page.c
>> @@ -482,6 +482,7 @@ void cl_page_disown0(const struct lu_env *env,
>>  int cl_page_is_owned(const struct cl_page *pg, const struct cl_io *io)
>>  {
>>       struct cl_io *top = cl_io_top((struct cl_io *)io);
>> +
>>       LINVRNT(cl_object_same(pg->cp_obj, io->ci_obj));
>>       return pg->cp_state == CPS_OWNED && pg->cp_owner == top;
>>  }
>
> This is not related to the patch but I don't understand CLOBINVRNT() and
> LINVRNT().
>
> # define LINVRNT(exp) LASSERT(exp)
> # define LINVRNT(exp) ((void)sizeof !!(exp))
>
> Why do we do the sizeof() instead of just an empty define?  The compiler
> calculates the size at compile time and doesn't execute the expression
> so it's the same as an empty define so far as I can tell.
>
> regards,
> dan carpenter



-- 
Jambhlekar Pushkar Arun