Date: Fri, 21 Jul 2000 17:26:47 +0200
Message-Id: <200007211526.RAA01901@loewis.home.cs.tu-berlin.de>
From: "Martin v. Loewis" <martin AT loewis DOT home DOT cs DOT tu-berlin DOT de>
To: eliz AT is DOT elta DOT co DOT il
CC: mrs AT windriver DOT com, djgpp-workers AT delorie DOT com, gcc AT gcc DOT gnu DOT org
In-reply-to: <200007210748.DAA10668@indy.delorie.com> (message from Eli
	Zaretskii on Fri, 21 Jul 2000 03:48:45 -0400 (EDT))
Subject: Re: GCC headers and DJGPP port
References: <200007192144 DOT OAA01294 AT kankakee DOT wrs DOT com> <200007200644 DOT CAA09337 AT indy DOT delorie DOT com> <200007201115 DOT NAA14806 AT loewis DOT home DOT cs DOT tu-berlin DOT de> <200007210748 DOT DAA10668 AT indy DOT delorie DOT com>
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> > PLEASE identify real problems caused by the actual contents of these
> > files, instead of merely reporting your imagination that there could
> > be problems.
> 
> Some of the definitions on these headers are private to the library.
> For example, math.h defines HUGE_VAL to a runtime constant
> __dj_huge_val.  limits.h defines several constants such as
> _POSIX_PATH_MAX that are specific to the library implementation.
> These are just a few examples.

I can understand that there is additional contents in your limits.h. I
fail to see what this has to do with GCC installing its own copy of
limits.h into a gcc directory. It is common in GCC installations to
have multiple copies of limits.h, and chain them together with
#include_next. This works very well on other GCC ports (e.g. Linux,
Solaris) - why doesn't it work on DJGPP?

> So we must try to minimize the problems in released versions,
> including problems that can happen when a new version of GCC is
> released which wasn't available at the time the library was
> developed and tested.

Forcing GCC not to install certain headers does not minimize
problems. Instead, if a new feature in GCC requires support in header
files, your port would break as your libraries would not provide that
support.

If you arrange that the DJGPP port follows the conventions of most
other ports, the danger of breaking things is smallest.

Regards,
Martin