From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Some experience with the igc branch Date: Thu, 26 Dec 2024 19:05:56 +0200 Message-ID: <86ldw2xtl7.fsf@gnu.org> References: <87o713wwsi.fsf@telefonica.net> <86o7112rnq.fsf@gnu.org> <867c7p2nz4.fsf@gnu.org> <87y104aih6.fsf@protonmail.com> <87ikr89gyp.fsf@protonmail.com> <87jzbn8zmu.fsf@protonmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="3468"; mail-complaints-to="usenet@ciao.gmane.io" Cc: pipcet@protonmail.com, gerd.moellmann@gmail.com, ofv@wanadoo.es, emacs-devel@gnu.org, eller.helmut@gmail.com, acorallo@gnu.org To: Stefan Kangas Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Dec 26 18:06:55 2024 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1tQrK3-0000hq-4H for ged-emacs-devel@m.gmane-mx.org; Thu, 26 Dec 2024 18:06:55 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tQrJE-0006e4-Ud; Thu, 26 Dec 2024 12:06:04 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tQrJ9-0006dl-Jk for emacs-devel@gnu.org; Thu, 26 Dec 2024 12:06:00 -0500 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tQrJ8-0000sx-R6; Thu, 26 Dec 2024 12:05:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=MIME-version:References:Subject:In-Reply-To:To:From: Date; bh=NFhAY8S9n4eTDB5a71S1DTzTybYJpj4KuYgBjXZ9z0I=; b=IsXynCKpUIWbAVRSfH96 qgDo2jLVhlDT2IgH45NV9xDmwpLTYU7fTc8uAbkVQi3KxBhHeeR2Z/s3WzVszp3xLXO66T0yGO7zS bwvRq+2PaDIIyaAWNjhJYgPrltNsDGXB1Fxwxesu4ytozfrQZKGuc+1R3YEkVeKtUN0i+6XSXucAb hXagzickqZhgOe2p4NEa/BgkKORXuFhNPnl6eryBprJgtZooO4w3RVPvyU4QHm4WrAj+IjuFfi3AR 0lQxL/8sV0VB/70nI0qNiiiP8rdOt8IMxqoGgu455wjh7hOPMszSDaid9omDg7d1Hj0Yuf5/nQhXa j1B8ZqEVCme+Xg==; In-Reply-To: (message from Stefan Kangas on Thu, 26 Dec 2024 16:12:52 +0000) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:327162 Archived-At: > From: Stefan Kangas > Date: Thu, 26 Dec 2024 16:12:52 +0000 > Cc: Gerd Möllmann , > Eli Zaretskii , ofv@wanadoo.es, emacs-devel@gnu.org, eller.helmut@gmail.com, > acorallo@gnu.org > > Pip Cet writes: > > > "Stefan Kangas" writes: > > > >> Which parts of C11 help us? > > > > stdatomic.h, in this case. > > Thanks for the explanation. > > > IIRC, C99 doesn't have usable memory barriers, not even for signal > > handler/main thread races such as this one. > > > > Of course almost every compiler that supports C99, and certainly all > > compilers usable for compiling Emacs, provides (or doesn't need, in the > > case of TinyCC) ways of implementing them. In the case of GCC, that > > used to be asm volatile ("" : : : "memory"). > > I don't think I understand what this means in practice. > > Can we use stdatomic.h with C99, or do you propose that we require C11? We will not require C11. We should see which platforms of those we care and can use MPS don't have stdatomic.h, and if any do, find solutions for them. All that assuming we need atomics, which is not yet established, AFIU.