Date: Fri, 10 May 1996 01:58:17 +0400 (MSD)
From: "Alexander V. Lukyanov" <lav AT video DOT yars DOT free DOT net>
Message-Id: <199605092158.BAA17237@video.yars.free.net>
To: alexlehm AT rbg DOT informatik DOT th-darmstadt DOT de, djgpp AT delorie DOT com
Subject: Re: vararg

> BTW. this would be another obstacle for using register calling, since when
> all fixed parameters are passed in registers, it is not possible to take a
> pointer to index the variable arguments list. I think BCC handles this by using
> a pseudo variable ..., which contains the address of the first ... argument,
> something like this would have to be introduced in gcc also.

the following macro I've found in stdarg.h coming with gcc:

#define va_start(AP, LASTARG) 						\
 (AP = ((__gnuc_va_list) __builtin_next_arg (LASTARG)))

maybe __builtin_next_arg is what you are looking for.