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

[Dmitri Vorobiev <dmitri.vorobiev@gmail.com>]

Adrian Bunk пишет:
> On Sat, Jan 26, 2008 at 06:35:41PM +0000, Tigran Aivazian wrote:
>> On Sat, 26 Jan 2008, Dmitri Vorobiev 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;"
> 
> Only depending on the compiler, and recent gcc versions are quite good 
> at optimizing code.
> 
>> I am surprized that this script complains about them as it is a perfectly 
>> valid thing to do in C.
> 
> Checkpatch warns about the something already documented in 
> Documentation/CodingStyle:
> 
> <--  snip  -->
> 
> Don't put multiple assignments on a single line either.  Kernel coding style
> is super simple.  Avoid tricky expressions.
> 
> <--  snip  -->
> 
> Nobody claims it wasn't perfectly valid C code, the point is that 
> multiple assignments on a single line are harder to read.

Thanks for your explanation. So, it was just a matter of readability,
not language lawyering. In fact, this is how I interpreted that complaint
from the checkpatch.pl script.

Dmitri

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