From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <1709339a44febca19fd2e2f36c780d0d@quanstro.net>
From: erik quanstrom <quanstro@quanstro.net>
Date: Thu, 24 Jan 2008 17:07:59 -0500
To: 9fans@cse.psu.edu
Subject: Re: [9fans] stdarg & va_copy
In-Reply-To: <20080124220045.07FBD1E8C1C@holo.morphisms.net>
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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