Re: Checkpatch.pl false positive? "ERROR: return is not a function, parentheses are not required"

[Andy Whitcroft <apw@canonical.com>]

On Sun, Mar 28, 2010 at 10:28:13PM +0300, Olimpiu Pascariu wrote:
> Hi,
> 
> I've used checkpatch.pl to verify drivers/staging/dt3155/dt3155_isr.c,
> in order to provide a patch which fixes the errors and warnings found by
> checkpatch.
> The script returns the following error:
> ERROR: return is not a function, parentheses are not required
> #155: FILE: staging/dt3155/dt3155_isr.c:155:
> +  return (dt3155_fbuffer[m]->ready_head -
> 
> The original code is:
> 
>   return (dt3155_fbuffer[m]->ready_head -
>            dt3155_fbuffer[m]->ready_len +
>            dt3155_fbuffer[m]->nbuffers)%
>           (dt3155_fbuffer[m]->nbuffers);
> 
> I've deleted the the first open parenthesis and the last close
> parenthesis, and now the code looks like this:
> 
>   return (dt3155_fbuffer[m]->ready_head -
>            dt3155_fbuffer[m]->ready_len +
>            dt3155_fbuffer[m]->nbuffers)%
>           (dt3155_fbuffer[m]->nbuffers);
> 
> IMHO the code is correct, though an auxiliary variable could be used to
> avoid this error returned by checkpatch.pl. 

This code is indeed correct.  This is a bug in checkpatch, I think I
have sorted out the bug in the version below (which should be mirrored
out shortly).  If you could test the version below and let me know that
would be helpful:

  http://www.kernel.org/pub/linux/kernel/people/apw/checkpatch/checkpatch.pl-testing

-apw