Re: [Qemu-devel] [PATCH] CODING_STYLE: update line length and mixed declaration rules

[Andreas Färber]

Am 19.06.2015 um 09:29 schrieb Paolo Bonzini:
> 1) Line lengths above 80 characters do exist.  They are rare, but
> they happen from time to time.  An ignored rule is worse than an
> exception to the rule, so do the latter.
> 
> 2) Mixed declarations also do exist at the top of #ifdef blocks.
> Remark on this particular usage and suggest an alternative.
> 
> Cc: Andreas Faerber <address@hidden>
> Cc: Markus Armbruster <address@hidden>
> Cc: Eduardo Habkost <address@hidden>
> Signed-off-by: Paolo Bonzini <address@hidden>
> ---
>  CODING_STYLE          | 21 ++++++++++++++++-----
>  scripts/checkpatch.pl |  9 ++++++---
>  2 files changed, 22 insertions(+), 8 deletions(-)
> 
> diff --git a/CODING_STYLE b/CODING_STYLE
> index d46cfa5..d013cb8 100644
> --- a/CODING_STYLE
> +++ b/CODING_STYLE
> @@ -31,7 +31,11 @@ Do not leave whitespace dangling off the ends of lines.
>  
>  2. Line width
>  
> -Lines are 80 characters; not longer.
> +Lines should be 80 characters; try not to make them longer.
> +
> +Sometimes it is hard to do, especially when dealing with QEMU subsystems
> +that use long function or symbol names.  Even in that case, do not make
> +lines _much_ longer than 80 characters.

Anthony had always allowed sensible exceptions to that rule, so +1 for
reformulating it here.

However, I would suggest that in that case we should lower the
recommendation/warning to 78 chars, with the rationale of not only the
actual code but also two-way diffs (79 chars plus +/-/space) and
three-way diffs (78 chars plus 2x +/-/space) fitting into standard 80x24
windows.

Either way, can you please decouple the two changes?

Regards,
Andreas

>  
>  Rationale:
>   - Some people like to tile their 24" screens with a 6x4 matrix of 80x24
> @@ -39,6 +43,8 @@ Rationale:
>     let them keep doing it.
>   - Code and especially patches is much more readable if limited to a sane
>     line length.  Eighty is traditional.
> + - The four-space indentation makes the most common excuse ("But look
> +   at all that white space on the left!") moot.
>   - It is the QEMU coding style.
>  
>  3. Naming
[snip]

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