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Date:   Tue, 2 May 2023 17:26:30 +0200
From:   Simon Horman <simon.horman@corigine.com>
To:     Dominique Martinet <asmadeus@codewreck.org>
Cc:     Eric Van Hensbergen <ericvh@gmail.com>,
        Latchesar Ionkov <lucho@ionkov.net>,
        Christian Schoenebeck <linux_oss@crudebyte.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, v9fs@lists.linux.dev,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH 5/5] 9p: remove dead stores (variable set again without
 being read)
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References: <20230427-scan-build-v1-0-efa05d65e2da@codewreck.org>
 <20230427-scan-build-v1-5-efa05d65e2da@codewreck.org>
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On Thu, Apr 27, 2023 at 08:23:38PM +0900, Dominique Martinet wrote:
> The 9p code for some reason used to initialize variables outside of the
> declaration, e.g. instead of just initializing the variable like this:
> 
> int retval = 0
> 
> We would be doing this:
> 
> int retval;
> retval = 0;
> 
> This is perfectly fine and the compiler will just optimize dead stores
> anyway, but scan-build seems to think this is a problem and there are
> many of these warnings making the output of scan-build full of such
> warnings:
> fs/9p/vfs_inode.c:916:2: warning: Value stored to 'retval' is never read [deadcode.DeadStores]
>         retval = 0;
>         ^        ~
> 
> I have no strong opinion here, but if we want to regularily run

s/regularily/regularly/

> scan-build we should fix these just to silence the messages.
> 
> I've confirmed these all are indeed ok to remove.

Likewise, these look good to me.

> Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>

Reviewed-by: Simon Horman <simon.horman@corigine.com>