9fans - fans of the OS Plan 9 from Bell Labs
 help / color / mirror / Atom feed
From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] stdarg & va_copy
Date: Thu, 24 Jan 2008 17:07:59 -0500	[thread overview]
Message-ID: <1709339a44febca19fd2e2f36c780d0d@quanstro.net> (raw)
In-Reply-To: <20080124220045.07FBD1E8C1C@holo.morphisms.net>

On Thu Jan 24 17:04:00 EST 2008, rsc@swtch.com wrote:
> > is there any reason that /$objtype/include/u.h does not
> > define va_copy?  are there objections to this c99 macro?
> 
> Yes.  The definition and semantics of va_copy are
> sufficiently murky that it seemed best to omit it.

i didn't see anything in the definition that would make va_copy
wrong given the plan 9 definition of va_list.  is there a particular
case on plan 9 that would be a problem?

> If you are porting code that uses va_copy, you can just
>     #define va_copy(x, y) (x) = (y)
> in your own compatibility headers.
> 
> I'm still annoyed that the C99 committee outlawed taking
> the address of a va_list.

understandable.  the whole thing is quite annoying.

but plan 9 does have va_start and va_end.  wouldn't make sense
to have va_copy as well?

- erik


  reply	other threads:[~2008-01-24 22:07 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-24 18:10 erik quanstrom
2008-01-24 22:00 ` Russ Cox
2008-01-24 22:07   ` erik quanstrom [this message]
2008-01-24 22:39     ` Russ Cox
2008-01-24 22:45       ` Pietro Gagliardi
2008-01-24 22:57         ` Charles Forsyth
2008-01-25  9:55 ` Douglas A. Gwyn
2008-01-25 14:18   ` erik quanstrom

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=1709339a44febca19fd2e2f36c780d0d@quanstro.net \
    --to=quanstro@quanstro.net \
    --cc=9fans@cse.psu.edu \
    /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).