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Subject: Re: [PATCH] erofs: suppress false positive last_block warning
To: Gao Xiang <hsiangkao@redhat.com>, <linux-erofs@lists.ozlabs.org>, Chao Yu
 <chao@kernel.org>
References: <20200528084844.23359-1-hsiangkao@redhat.com>
From: Chao Yu <yuchao0@huawei.com>
Message-ID: <4bc811ed-f406-1f77-94f7-5e61c4657001@huawei.com>
Date: Thu, 28 May 2020 17:25:05 +0800
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Cc: Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org
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On 2020/5/28 16:48, Gao Xiang wrote:
> As Andrew mentioned, some rare specific gcc versions could report
> last_block uninitialized warning. Actually last_block doesn't need
> to be uninitialized first from its implementation due to bio == NULL
> condition. After a bio is allocated, last_block will be assigned
> then.
> 
> The detailed analysis is in this thread [1]. So let's silence those
> confusing gccs simply.
> 
> [1] https://lore.kernel.org/r/20200421072839.GA13867@hsiangkao-HP-ZHAN-66-Pro-G1
> 
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Gao Xiang <hsiangkao@redhat.com>

Reviewed-by: Chao Yu <yuchao0@huawei.com>

Thanks,