From: "John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: GCC 2.8.1 and NULL
Date: Sun, 28 Jun 1998 13:07:46 -0400
Organization: Two pounds of chaos and a pinch of salt.
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Gili wrote:
> 
>         Since GCC 2.8.1 (and perhaps a bit earlier) the authors have begun
> using "#define NULL __null".. One problem arises:
> 
> If #include <stdio.h> occures anywhere throughout my code (and since
> it is a very common library, it obviously does) I get the following
> message telling me that stdio.h tried to redefine NULL (which was
> previously defined as __null).. The only way I found around this is to
> stick an "#ifndef ... #endif" block before "#define NULL 0" command in
> <stdio.h>.. But what I'm wondering is, is this conflict suppose to
> exist? Is something wrong with my configuration? What's going on? :)

You may want to try always putting #include <stdio.h> as the first
include statement in your source files.  This allows the C++ libraries
to undefine or redefine NULL as they see fit.

This issue was discussed recently; you may be interested in looking it
up in the mail archives (http://www.delorie.com/djgpp/mail-archives/). 
I don't recall exactly what solution we arrived at.

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