From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12958 invoked by alias); 7 Nov 2010 16:39:41 -0000 Received: (qmail 12905 invoked by uid 22791); 7 Nov 2010 16:39:40 -0000 X-SWARE-Spam-Status: No, hits=-2.1 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mail.physik.uni-muenchen.de (HELO mail.physik.uni-muenchen.de) (192.54.42.129) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sun, 07 Nov 2010 16:39:35 +0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.physik.uni-muenchen.de (Postfix) with ESMTP id B5D5028054; Sun, 7 Nov 2010 17:39:32 +0100 (CET) Received: from mail.physik.uni-muenchen.de ([127.0.0.1]) by localhost (mail.physik.uni-muenchen.de [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 8evAYgV0dj6E; Sun, 7 Nov 2010 17:39:32 +0100 (CET) Received: from tobias-schluters-computer.local (e181035253.adsl.alicedsl.de [85.181.35.253]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.physik.uni-muenchen.de (Postfix) with ESMTP id 6946D28051; Sun, 7 Nov 2010 17:39:31 +0100 (CET) Message-ID: <4CD6D640.7040806@physik.uni-muenchen.de> Date: Sun, 07 Nov 2010 16:39:00 -0000 From: =?ISO-8859-1?Q?Tobias_Schl=FCter?= User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.12) Gecko/20101027 Thunderbird/3.1.6 MIME-Version: 1.0 To: Janus Weil CC: Tobias Burnus , Dominique Dhumieres , fortran , gcc-patches , tkoenig Subject: Re: [Patch, Fortran, OOP] PR 46313: OOP-ABI issue, ALLOCATE issue, CLASS renaming issue References: <20101106233415.7DA533BE18@mailhost.lps.ens.fr> <4CD65B85.8030903@net-b.de> <4CD6977B.6010002@physik.uni-muenchen.de> <4CD6A751.6090807@net-b.de> <4CD6C713.2020709@physik.uni-muenchen.de> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact fortran-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: fortran-owner@gcc.gnu.org X-SW-Source: 2010-11/txt/msg00125.txt.bz2 On 2010-11-07 16:49, Janus Weil wrote: > Btw, what is the reason for the macro adding *two* underscores in > front, instead of just one? I got curious and did some googling. Tthe C standard has this: 7.1.3 Reserved identifiers Each header declares or defines all identifiers listed in its associated subclause, and optionally declares or defines identifiers listed in its associated future library directions subclause and identifiers which are always reserved either for any use or for use as file scope identifiers. * All identifiers that begin with an underscore and either an uppercase letter or another underscore are always reserved for any use. ... So if the compiler can't use a character the user can't put into identifiers ('.' or '$'), it reverts to something that isn't allowed to put into identifiers: two underscores in the beginning. I think the lesson for us is: '.' and '$' aren't portable. Cheers, - Tobi