From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: ABI incompatibilities with MinGW GCC 4.7.0 Date: Sat, 09 Jun 2012 17:55:38 +0300 Message-ID: <83aa0cttzp.fsf@gnu.org> References: <83ipf2ustm.fsf@gnu.org> <871ulopu3r.fsf@Rainer.invalid> <83k3zgtywl.fsf@gnu.org> <878vfwv93i.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: dough.gmane.org 1339253748 4188 80.91.229.3 (9 Jun 2012 14:55:48 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sat, 9 Jun 2012 14:55:48 +0000 (UTC) Cc: Stromeko@nexgo.de, emacs-devel@gnu.org To: Jason Rumney Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Jun 09 16:55:47 2012 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1SdN4q-00073W-6j for ged-emacs-devel@m.gmane.org; Sat, 09 Jun 2012 16:55:44 +0200 Original-Received: from localhost ([::1]:50374 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SdN4p-0006M5-VA for ged-emacs-devel@m.gmane.org; Sat, 09 Jun 2012 10:55:43 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:46854) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SdN4k-0006Lx-Nk for emacs-devel@gnu.org; Sat, 09 Jun 2012 10:55:41 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SdN4i-00066I-Sy for emacs-devel@gnu.org; Sat, 09 Jun 2012 10:55:38 -0400 Original-Received: from mtaout21.012.net.il ([80.179.55.169]:34027) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SdN4i-00065v-Kp; Sat, 09 Jun 2012 10:55:36 -0400 Original-Received: from conversion-daemon.a-mtaout21.012.net.il by a-mtaout21.012.net.il (HyperSendmail v2007.08) id <0M5C00E00UJB9000@a-mtaout21.012.net.il>; Sat, 09 Jun 2012 17:55:34 +0300 (IDT) Original-Received: from HOME-C4E4A596F7 ([87.69.210.75]) by a-mtaout21.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0M5C00E8YUSM5O80@a-mtaout21.012.net.il>; Sat, 09 Jun 2012 17:55:34 +0300 (IDT) In-reply-to: <878vfwv93i.fsf@gnu.org> X-012-Sender: halo1@inter.net.il X-detected-operating-system: by eggs.gnu.org: Solaris 10 (beta) X-Received-From: 80.179.55.169 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:150859 Archived-At: > From: Jason Rumney > Cc: Achim Gratz , emacs-devel@gnu.org > Date: Sat, 09 Jun 2012 22:44:01 +0800 > > Eli Zaretskii writes: > > >> I still think that simply adding '-mno-ms-bitfields' to the build is all > >> you need for Emacs > > > > If we know the libraries out there are not built with GCC 4.7.x, then > > this is indeed the way to go. But what about people who like to build > > all their libraries themselves? if they use GCC 4.7 to build their > > libraries, and don't make a point of using '-mno-ms-bitfields' when > > they do, we cannot let them build Emacs with '-mno-ms-bitfields', can > > we? > > The GTK binaries available for Windows have been built with > -mms-bitfields for some years now, and the image libraries contained > within them have worked without problem with Emacs for all that time. So > I think the choice of whether to build with or without that flag is a > non-issue for Emacs. What is true for some libraries might be false for others. It all depends whether a library triggers the code generation where this switch makes the difference. > > And then there's the issue of other ABI changes, if there are any. > > That is the really disturbing part, because the bitfields issue rarely > > if at all affects real-life code. > > It is somewhat disturbing that the MinGW-GCC maintainers themselves are > unsure about other ABI changes, but I doubt that any of them will affect > pure C code except maybe in more rare corner cases like the bitfield > issue. A I said, I hope you are right. But until we _know_ for sure, I think it's prudent to tell people to stay away of the new version, which was the sole purpose of my OP. If you are saying that people can safely disregard this issue, then I very much disagree.