SUMMARY: compile using gcc with varargs.h

From: Mr. Santithorn Bunchua (
Date: Sun Jan 30 1994 - 17:56:31 CST

My problem:

        I cannot compile program with "#include <varargs.h>".
        The error was ... __builtin_va_arg_incr is undefined.

The solutions I received are:

        1) __builtin_va_arg_incr is special name for Sun
           compiler which gcc doesn't recognize.
        2) gcc has its own set of include files including
           the new varargs.h.
        3) On my machine, the new varargs.h is in
           LIBDIR/include/tmpdir/varargs.h so I move it out
           to LIBDIR/include/varargs.h so that gcc will find
           it... and everything is ok.

Special thanks to:
        Kayvan Sylvan <kayvan@satyr.Sylvan.COM>
        Sven Heinicke <>
        Joe McGuckin <oilean!>

>From kayvan@satyr.Sylvan.COM Sun Jan 30 01:10:19 1994
Date: Mon, 24 Jan 94 19:11 PST
From: Kayvan Sylvan <kayvan@satyr.Sylvan.COM>
To: "Mr. Santithorn Bunchua" <>
Subject: Compiling program with <varargs>

There's a typo in Sun's header file.

I don't have the source in front of me right now, but I remember
reporting this and fixing it while I was working as a consultant at

What I remember is that there were two sections that define the
varargs based on the compiler and use a couple of variables. The
variables are named incorrectly in the section that gcc sees.


| Kayvan Sylvan, Sylvan Associates, kayvan@satyr.Sylvan.COM, (408) 978-1407 |
| Consulting, Training, Development, SysAdmin, {BSD,SVr3,SVr4} Unix Systems |
| "Think Globally, Act Locally." "Only you can make your dreams come true." |
| Proud Dad of Katherine Yelena (born 8/8/89) & Robin Gregory (born 2/28/92) |

>From Sun Jan 30 01:10:09 1994
Date: Tue, 25 Jan 94 09:23:12 -0500
From: Sven Heinicke <>
To: "Mr. Santithorn Bunchua" <>
Subject: Re: Compiling program with <varargs>

I hacked around with your code and it worked no problem (my final code
is appended at the end of this message). What version of gcc are you
using? Here is what I'm using:

% gcc -v
Reading specs from /usr/local/lib/gcc-lib/sparc-sun-solaris2.2/2.5.2/specs
gcc version 2.5.2

Perhaps your version of gcc is installed wrong. check out which
varargs.h file you are loading. Make the first line of your c program
'#include <varargs.h>' and then do this (Assuming your C program is
called t.c):

gcc -E t.c > t.i

One of the first lines of t.c should look something like:

# 1 "/usr/local/lib/gcc-lib/sparc-sun-solaris2.2/2.5.2/include/varargs.h" 1 3

how does it look?

oh, I just thought of something else. are you using the ftp'd
solaris2 binaries or the binaries off the demo CD? If so the first
thing you should do is down load the latest version and rebuild it.
People have gotten a lot of strange problems downloading binaries. I
downloaded the binaries and the first thing I did was download the
latest GCC sources and rebuild it. If this is the problem recontact
me too as there are a few instructions you should know about building
the GNU gcc with the solaris2 binaries.


#include <varargs.h>

  test (1, 2, 3, 0);

void test (va_alist)
  va_list ap;
  int p;
  va_start (ap);
  while ( (p = va_arg (ap, int)) != 0)
      printf ("%d", p);
  va_end (ap);
>From oilean! Sun Jan 30 01:10:03 1994
Date: Mon, 24 Jan 94 22:32:33 PST
From: Joe McGuckin <oilean!>
Subject: Re: Compiling program with <varargs>

The __builtin_va_arg_incr symbol is a magic cookie that the Sun compilers recognize -
this tells them to generate code for varargs parameter passing. The Gnu compilers
probably don't treat the __builtin_va_arg_incr symbol as 'special' - they treat it as a
normal symbol.

I suggest that you use the Gnu headers if they are available.



This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:08:55 CDT