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Re: How do we write unused arguments?
- From: Richard Earnshaw <Richard dot Earnshaw at foss dot arm dot com>
- To: Jakub Jelinek <jakub at redhat dot com>, Marek Polacek <polacek at redhat dot com>
- Cc: Bernd Schmidt <bschmidt at redhat dot com>, gcc at gcc dot gnu dot org
- Date: Thu, 5 Nov 2015 11:19:36 +0000
- Subject: Re: How do we write unused arguments?
- Authentication-results: sourceware.org; auth=none
- References: <563B221B dot 9070806 at redhat dot com> <20151105104524 dot GU3185 at redhat dot com> <20151105104855 dot GW478 at tucnak dot redhat dot com>
On 05/11/15 10:48, Jakub Jelinek wrote:
> On Thu, Nov 05, 2015 at 11:45:24AM +0100, Marek Polacek wrote:
>> On Thu, Nov 05, 2015 at 10:32:11AM +0100, Bernd Schmidt wrote:
>>> When reviewing patches I'm never quite sure which of the following we should
>>> be using:
>>>
>>> some_target_hook (tree decl, machine_mode mode ATTRIBUTE_UNUSED)
>>>
>>> some_target_hook (tree decl, machine_mode ARG_UNUSED (mode))
>>>
>>> some_target_hook (tree decl, machine_mode /* mode */)
>>>
>>> some_target_hook (tree decl, machine_mode)
>>>
>>> Any opinions? I'm leaning towards the last version since it's idiomatic in
>>> the language we're using and has the least amount of visual clutter. If no
>>> one comments, I'll start enforcing that in patch reviews. Currently no one
>>> seems sure and everything is getting totally inconsistent.
>>
>> FWIW, I also like the last version best.
>
> It depends, if the argument is conditionally (based on preprocessor macros)
> used, then we need the first form.
> If it is completely unused, I also prefer the last form, but there are cases
> where one wants to document the purpose of the unused argument or something
> similar and in that case the third one is useful.
>
> Jakub
>
Except, of course, that we're moving away from conditionally compiled
code, so we should never need the first (or second) forms.