From: Anthony Liguori <anthony@codemonkey.ws>
To: Blue Swirl <blauwirbel@gmail.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>,
qemu-devel <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] Re: [PATCH 1/5] HACKING: add preprocessor rules
Date: Mon, 16 Aug 2010 13:32:31 -0500 [thread overview]
Message-ID: <4C69843F.7060103@codemonkey.ws> (raw)
In-Reply-To: <AANLkTin1B_VUpV5rHfxL=g=KHJBM88CYAx_d6pJ=Fv2D@mail.gmail.com>
On 08/16/2010 01:05 PM, Blue Swirl wrote:
> On Sun, Aug 15, 2010 at 9:27 PM, Andreas Schwab<schwab@linux-m68k.org> wrote:
>
>> Blue Swirl<blauwirbel@gmail.com> writes:
>>
>>
>>> +For variadic macros, stick with C99 syntax:
>>> +
>>> +#define DPRINTF(fmt, ...) \
>>> + do { printf("IRQ: " fmt, ## __VA_ARGS__); } while (0)
>>>
>> That's not C99 syntax, the combination with ## is a gcc extension. In
>> C99 you cannot have an empty __VA_ARGS__.
>>
> That's too bad, I picked the example from one of our current macros.
> Maybe just s/C99/this/ or perhaps we shouldn't specify any
> non-standard syntax.
>
We definitely should discourage the GCC syntax [#define fn(arg...)] as
it's deprecated by the new C99 syntax. Very specifically, only the '##'
is an extension and it's a widely adopted one.
Regards,
Anthony Liguori
next prev parent reply other threads:[~2010-08-16 18:32 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-15 17:50 [Qemu-devel] [PATCH 1/5] HACKING: add preprocessor rules Blue Swirl
2010-08-15 21:27 ` [Qemu-devel] " Andreas Schwab
2010-08-16 18:05 ` Blue Swirl
2010-08-16 18:32 ` Anthony Liguori [this message]
2010-08-17 17:40 ` Blue Swirl
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4C69843F.7060103@codemonkey.ws \
--to=anthony@codemonkey.ws \
--cc=blauwirbel@gmail.com \
--cc=qemu-devel@nongnu.org \
--cc=schwab@linux-m68k.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).