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Date:   Tue, 2 May 2023 17:27:09 +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 4/5] 9p: virtio: skip incrementing unused variable
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References: <20230427-scan-build-v1-0-efa05d65e2da@codewreck.org>
 <20230427-scan-build-v1-4-efa05d65e2da@codewreck.org>
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On Thu, Apr 27, 2023 at 08:23:37PM +0900, Dominique Martinet wrote:
> Fix the following scan-build warning:
> net/9p/trans_virtio.c:504:3: warning: Value stored to 'in' is never read [deadcode.DeadStores]
>                 in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM,
>                 ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> I'm honestly not 100% sure about this one; I'm tempted to think we
> could (should?) just check the return value of pack_sg_list_p to skip
> the in_sgs++ and setting sgs[] if it didn't process anything, but I'm
> not sure it should ever happen so this is probably fine as is.
> 
> Just removing the assignment at least makes it clear the return value
> isn't used, so it's an improvement in terms of readability.
> 
> Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>

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