Re: [PATCH v2 8/9] bfs: remove multiple assignments

From: Dmitri Vorobiev
Date: Wed Jan 30 2008 - 08:37:39 EST


Al Viro wrote:
> On Mon, Jan 28, 2008 at 01:02:03AM -0600, Joel Schopp wrote:
>>>>> - inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
>>>>> + inode->i_mtime = CURRENT_TIME_SEC;
>>>>> + inode->i_atime = CURRENT_TIME_SEC;
>>>>> + inode->i_ctime = CURRENT_TIME_SEC;
>>>> multiple assignments like "x = y = z = value;" can potentially
>>>> (depending on the compiler and arch) be faster than "x = value; y =
>>>> value; z=value;"
>>>>
>>>> I am surprized that this script complains about them as it is a
>>>> perfectly valid thing to do in C.
>>> I think it seems wise to ask the maintainers of checkpatch.pl to
>>> comment on that. I'm Cc:ing them now.
>>>
>> There are plenty of things that are valid to do in C that don't make for
>> maintainable code. These scripts are designed to make your code easier for
>> real people to review and maintain.
>
> Except that in this case the new variant is not equivalent to the old one...

Yes, you're right. In fact, I felt like sending yet another version
of these patches, but this gets preempted all the time by "the other things".

Dmitri
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