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From: Wolfram Sang <wsa+renesas@sang-engineering.com>
To: Zhen Lei <thunder.leizhen@huawei.com>
Cc: linux-i2c <linux-i2c@vger.kernel.org>,
	linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/1] i2c: sh_mobile: eliminate a misreported warning
Date: Fri, 29 May 2020 14:15:01 +0200	[thread overview]
Message-ID: <20200529121501.GB20272@ninjato> (raw)
In-Reply-To: <20200429124017.397-1-thunder.leizhen@huawei.com>

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On Wed, Apr 29, 2020 at 08:40:17PM +0800, Zhen Lei wrote:
> The warning is caused by the branches "if (pd->pos == -1)" and
> "if (pd->pos == 0)", because they appear after "real_pos = pd->pos - 2",
> so the compiler doesn't known the value of real_pos is negative through
> these two branches.
> 
> To avoid this warning, eliminate the middleman "data".
> 
> drivers/i2c/busses/i2c-sh_mobile.c: In function ‘sh_mobile_i2c_isr’:
> drivers/i2c/busses/i2c-sh_mobile.c:396:26: warning: ‘data’ may be used uninitialized in this function [-Wmaybe-uninitialized]
>    pd->msg->buf[real_pos] = data;
>                           ^
> drivers/i2c/busses/i2c-sh_mobile.c:369:16: note: ‘data’ was declared here
>   unsigned char data;
> 
> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>

Thanks for the patch and reminding me about the issue, it is correct.
However, an identical patch has been sent before and is now applied in
for-next:

http://patchwork.ozlabs.org/project/linux-i2c/patch/f526f90ea62741716de2ecfa310ba22d8cf1d3c2.1557377015.git.viresh.kumar@linaro.org/


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      reply	other threads:[~2020-05-29 12:15 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-29 12:40 [PATCH 1/1] i2c: sh_mobile: eliminate a misreported warning Zhen Lei
2020-05-29 12:15 ` Wolfram Sang [this message]

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