Message-ID: <564CC5DB.8000104@linaro.org>
Date: Wed, 18 Nov 2015 10:39:23 -0800
From: "Shi, Yang" <yang.shi@linaro.org>
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0
MIME-Version: 1.0
To: Tejun Heo <tj@kernel.org>
CC: Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, linaro-kernel@lists.linaro.org
Subject: Re: [PATCH] writeback: initialize m_dirty to avoid compile warning
References: <1447439201-32009-1-git-send-email-yang.shi@linaro.org> <20151117153855.99d2acd0568d146c29defda5@linux-foundation.org> <20151118181142.GC11496@mtj.duckdns.org> <564CC314.1090904@linaro.org> <20151118183344.GD11496@mtj.duckdns.org>
In-Reply-To: <20151118183344.GD11496@mtj.duckdns.org>
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1321
Lines: 41

On 11/18/2015 10:33 AM, Tejun Heo wrote:
> Hello,
>
> On Wed, Nov 18, 2015 at 10:27:32AM -0800, Shi, Yang wrote:
>>> This was the main reason the code was structured the way it is.  If
>>> cgroup writeback is not enabled, any derefs of mdtc variables should
>>> trigger warnings.  Ugh... I don't know.  Compiler really should be
>>> able to tell this much.
>>
>> Thanks for the explanation. It sounds like a compiler problem.
>>
>> If you think it is still good to cease the compile warning, maybe we could
>
> If this is gonna be a problem with new gcc versions, I don't think we
> have any other options. :(
>
>> just assign it to an insane value as what Andrew suggested, maybe
>> 0xdeadbeef.
>
> I'd just keep it at zero.  Whatever we do, the effect is gonna be
> difficult to track down - it's not gonna blow up in an obvious way.
> Can you please add a comment tho explaining that this is to work
> around compiler deficiency?

Sure.

Other than this, in v2, I will just initialize m_dirty since compiler 
just reports it is uninitialized.

Thanks,
Yang

>
> Thanks.
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/