Path: utzoo!attcan!uunet!husc6!bloom-beacon!mit-eddie!ll-xn!ames!umd5!brl-adm!brl-smoke!gwyn
From: gwyn@brl-smoke.ARPA (Doug Gwyn )
Newsgroups: comp.lang.c
Subject: Re: #pragma
Message-ID: <7960@brl-smoke.ARPA>
Date: 23 May 88 18:19:23 GMT
References: <54080@sun.uucp> <11608@mimsy.UUCP> <7950@brl-smoke.ARPA> <1988May23.012636.1719@utzoo.uucp> <2765@umd5.umd.edu>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 21

In article <2765@umd5.umd.edu> chris@trantor.umd.edu (Chris Torek) writes:
>I took advantage of that clause to make a version of cpp which
>warns about #pragma.  The reasoning works as follows:  The
>`implementation-defined' manner can be almost anything (GNU cpp
>runs rogue, which appears to be perfectly legal), so long as the
>compiler `recognises' the #pragma.

The GNU C preprocessor does NOT run rogue when #pragma is
encountered.  (It used to, before this business was explained
to Stallman and crew.)

I explained how you need to understand #pragma.  You cannot
understand it while applying tunnel vision, taking one part
of the specification, dropping its context, and attempting
to make sense of what remains by linguistic analysis.  It
doesn't work for philosophy and it also doesn't work for
complex technical specifications.

I think #pragma is nearly useless, by the way.  Its main use
seems to be to enable various listing, (conforming) optimization,
and debugging levels, and even that is implementation-specific.