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Subject: Re: [PATCH] inotify: fix minmax.cocci warnings
To:     Julia Lawall <julia.lawall@inria.fr>, Jan Kara <jack@suse.cz>
Cc:     Amir Goldstein <amir73il@gmail.com>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, kbuild-all@lists.01.org
References: <alpine.DEB.2.22.394.2104062246500.19097@hadrien>
 <20210407160546.GA3271@quack2.suse.cz>
 <alpine.DEB.2.22.394.2104071901260.11549@hadrien>
From:   Denis Efremov <efremov@linux.com>
Message-ID: <bd17554f-a8d8-3fd8-b3b6-e3c2d86d7f99@linux.com>
Date:   Thu, 8 Apr 2021 09:22:02 +0300
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On 4/7/21 8:02 PM, Julia Lawall wrote:
> 
> 
> On Wed, 7 Apr 2021, Jan Kara wrote:
> 
>> On Tue 06-04-21 22:49:26, Julia Lawall wrote:
>>> From: kernel test robot <lkp@intel.com>
>>>
>>> Opportunity for min().
>>>
>>> Generated by: scripts/coccinelle/misc/minmax.cocci
>>>
>>> Fixes: 8636e3295ce3 ("coccinelle: misc: add minmax script")
>>> CC: Denis Efremov <efremov@linux.com>
>>> Reported-by: kernel test robot <lkp@intel.com>
>>> Signed-off-by: kernel test robot <lkp@intel.com>
>>> Signed-off-by: Julia Lawall <julia.lawall@inria.fr>
>> ...
>>> --- a/fs/notify/inotify/inotify_user.c
>>> +++ b/fs/notify/inotify/inotify_user.c
>>> @@ -382,7 +382,7 @@ static int inotify_add_to_idr(struct idr
>>>
>>>  	spin_unlock(idr_lock);
>>>  	idr_preload_end();
>>> -	return ret < 0 ? ret : 0;
>>> +	return min(ret, 0);
>>>  }
>>
>> Honestly, while previous expression is a standard idiom for "if 'ret' holds
>> an error, return it", the new expression is harder to understand for me. So
>> I prefer to keep things as they are in this particular case...
> 
> OK, I had doubts about it as well, but I forwarded it because I found them
> equally obscure...
> 
> Denis, maybe the semantic patch should be updated to avoid this case.

No problem, I'll send an update.

Thanks,
Denis