X-Authentication-Warning: delorie.com: mail set sender to djgpp-workers-bounces using -f
Date: Wed, 11 Aug 2004 21:01:23 +0300
From: "Eli Zaretskii" <eliz AT gnu DOT org>
Sender: halo1 AT zahav DOT net DOT il
To: djgpp-workers AT delorie DOT com
Message-Id: <1438-Wed11Aug2004210123+0300-eliz@gnu.org>
X-Mailer: emacs 21.3.50 (via feedmail 8 I) and Blat ver 1.8.9
In-reply-to: <411A0EEF.F3DA04B4@yahoo.com> (message from CBFalconer on Wed, 11
	Aug 2004 08:19:59 -0400)
Subject: Re: Fix for environ pollution
References: <10408102240 DOT AA89930 AT clio DOT rice DOT edu> <2719-Wed11Aug2004065357+0300-eliz AT gnu DOT org> <411A0EEF DOT F3DA04B4 AT yahoo DOT com>
Reply-To: djgpp-workers AT delorie DOT com
Errors-To: nobody AT delorie DOT com
X-Mailing-List: djgpp-workers AT delorie DOT com
X-Unsubscribes-To: listserv AT delorie DOT com
Precedence: bulk

> Date: Wed, 11 Aug 2004 08:19:59 -0400
> From: CBFalconer <cbfalconer AT yahoo DOT com>
> 
> Just thinking out loud.  That means that, within main only, and in
> the DJGPP stack environment, the system has to translate the word
> 'environ' to access the space for a third parameter to main.

No, I don't think so.  The startup code calls `main' with 3 argument,
the 3rd being the addres of environ[0].  So a program that declares
`main' with 3 args will get the environment, and if it doesn't, it
won't.  No magic translation is required.

> This is in the compiler proper.  That access has to be removed if
> the -ansi directive is in force.

??? AFAIK, ANSI C does support the 3rd argument to `main'.  So we
cannot remove it under -ansi.

> Thus the library proper is not affected, and can supply any names
> desired in either user or system space, provided they are in
> separate modules and not loaded unless specified.  The whole thing
> is therefore a GCC bug, not a library bug.

No, the problem _is_ in the library (or, rather, in the startup code,
but that also belongs to the library).  `environ' is defined in the
startup code (because it calls `main' with its pointer), and since the
startup code is _always_ linked into the program, the symbol is always
there, and it has an external linkage.