From: Lino Sanfilippo <LinoSanfilippo@gmx.de>
To: Joe Perches <joe@perches.com>, David Miller <davem@davemloft.net>,
lsanfil@marvell.com
Cc: madalin.bucur@nxp.com, akpm@linux-foundation.org, corbet@lwn.net,
netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
linux-kernel@vger.kernel.org, oss@buserror.net,
ppc@mindchasers.com, pebolle@tiscali.nl,
joakim.tjernlund@transmode.se,
Randy Dunlap <rdunlap@infradead.org>
Subject: Re: Coding Style: Reverse XMAS tree declarations ?
Date: Fri, 4 Nov 2016 21:06:58 +0100 [thread overview]
Message-ID: <31ace8dd-1e42-2762-6367-028068d4d816@gmx.de> (raw)
In-Reply-To: <1478281455.1924.41.camel@perches.com>
On 04.11.2016 18:44, Joe Perches wrote:
> On Fri, 2016-11-04 at 11:07 -0400, David Miller wrote:
>> From: Lino Sanfilippo <lsanfil@marvell.com>
>> > On 04.11.2016 07:53, Joe Perches wrote:
>> >> CHECK:REVERSE_XMAS_TREE: Prefer ordering declarations longest to
>> >> shortest
>> >> #446: FILE: drivers/net/ethernet/ethoc.c:446:
>> >> + int size = bd.stat >> 16;
>> >> + struct sk_buff *skb;
>> > should not this case be valid? Optically the longer line is already
>> > before the shorter.
>> > I think that the whole point in using this reverse xmas tree ordering
>> > is to have
>> > the code optically tidied up and not to enforce ordering between
>> > variable name lengths.
>>
>> That's correct.
>
> And also another reason the whole reverse xmas tree
> automatic declaration layout concept is IMO dubious.
>
> Basically, you're looking not at the initial ordering
> of automatics as important, but helping find a specific
> automatic when reversing from reading code is not always
> correct.
>
> Something like:
>
> static void function{args,...)
> {
> [longish list of reverse xmas tree identifiers...]
> struct foo *bar = longish_function(args, ...);
> struct foobarbaz *qux;
> [more identifers]
>
> [multiple screenfuls of code later...)
>
> new_function(..., bar, ...);
>
> [more code...]
> }
>
> and the reverse xmas tree helpfulness of looking up the
> type of bar is neither obvious nor easy.
>
In this case it is IMHO rather the declaration + initialization that makes
"bar" hard to find at one glance, not the use of RXT. You could do something like
[longish list of reverse xmas tree identifiers...]
struct foobarbaz *qux;
struct foo *bar;
bar = longish_function(args, ...);
to increase readability.
Personally I find it more readable to always use a separate line for initializations
by means of functions (regardless of whether the RXT scheme is used or not).
> My preference would be for a bar that serves coffee and alcohol.
>
At least a bar like this should not be too hard to find :)
Regards,
Lino
next prev parent reply other threads:[~2016-11-04 20:24 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-02 20:17 [PATCH net-next v6 00/10] dpaa_eth: Add the QorIQ DPAA Ethernet driver Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 01/10] devres: add devm_alloc_percpu() Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 02/10] dpaa_eth: add support for DPAA Ethernet Madalin Bucur
2016-11-03 19:58 ` David Miller
2016-11-04 6:53 ` Coding Style: Reverse XMAS tree declarations ? (was Re: [PATCH net-next v6 02/10] dpaa_eth: add support for DPAA Ethernet) Joe Perches
2016-11-04 11:01 ` Lino Sanfilippo
2016-11-04 15:07 ` Coding Style: Reverse XMAS tree declarations ? David Miller
2016-11-04 17:44 ` Joe Perches
2016-11-04 20:06 ` Lino Sanfilippo [this message]
2016-11-07 11:00 ` David Laight
2016-11-04 17:05 ` Coding Style: Reverse XMAS tree declarations ? (was Re: [PATCH net-next v6 02/10] dpaa_eth: add support for DPAA Ethernet) Randy Dunlap
2016-11-04 19:48 ` David VomLehn
2016-11-07 8:05 ` Michael Ellerman
2016-11-07 15:43 ` [PATCH net-next v6 02/10] dpaa_eth: add support for DPAA Ethernet Madalin-Cristian Bucur
2016-11-07 15:55 ` David Miller
2016-11-07 16:32 ` Madalin-Cristian Bucur
2016-11-07 16:39 ` David Miller
2016-11-07 16:59 ` Madalin-Cristian Bucur
2016-11-09 17:16 ` Madalin-Cristian Bucur
2016-11-09 17:18 ` David Miller
2016-11-07 16:25 ` Joakim Tjernlund
2016-11-02 20:17 ` [PATCH net-next v6 03/10] dpaa_eth: add option to use one buffer pool set Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 04/10] dpaa_eth: add ethtool functionality Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 05/10] dpaa_eth: add ethtool statistics Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 06/10] dpaa_eth: add sysfs exports Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 07/10] dpaa_eth: add trace points Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 08/10] arch/powerpc: Enable FSL_PAMU Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 09/10] arch/powerpc: Enable FSL_FMAN Madalin Bucur
2016-11-02 20:17 ` [PATCH net-next v6 10/10] arch/powerpc: Enable dpaa_eth Madalin Bucur
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