linux-kernel - Re: [PATCH] regmap: Fix compile warning with value uninitialized

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Message-ID: <527E86B9.2050306@linux.com>
Date:	Sat, 09 Nov 2013 20:02:17 +0100
From:	Levente Kurusa <levex@...ux.com>
To:	Mark Brown <broonie@...nel.org>,
	Caizhiyong <caizhiyong@...ilicon.com>
CC:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"Wanglin (Albert)" <albert.wanglin@...ilicon.com>
Subject: Re: [PATCH] regmap: Fix compile warning with value uninitialized

2013-11-09 19:57 keltezéssel, Mark Brown írta:
> On Sat, Nov 09, 2013 at 04:34:07PM +0100, Levente Kurusa wrote:
>> 2013-11-09 16:16 keltezéssel, Mark Brown írta:
> 
>>>> -	int i, ret;
>>>> +	int i;
>>>> +	int ret = 0;
>>>>  	bool bypass;
> 
>> Wouldn't the following be better?
> 
>> int i, ret = 0;
> 
>> I think it is more readable.
> 
> No, that's not the kernel coding style.
Alright.
> 
>>> This sort of fix isn't ideal, it just silences the warning but if the
>>> compiler has spotted a genuine oversight in the function it won't
>>> address it.  It's better to include some analysis of why this is a good
>>> fix.
> 
>> The only condition when 'ret' is not set is when the num_regs parameter is zero
>> and krealloc doesn't fail. If the above two conditions apply, then
>> the code would return an uninitialized value. However, calling this function with
>> num_regs == 0, would be a waste as it essentially does nothing.
> 
> OK, so that should be in the changelog - or there should be an error
> check for num_regs == 0 which might be more helpful.

Adding an explanation into the changelog and editing the patch
in a way so that it adds a check would be the best choice I think.

Cai, can you please do this as part of the patch?

-- 
Regards,
Levente Kurusa
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