From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS22989 209.51.188.0/24 X-Spam-Status: No, score=-3.9 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, RCVD_IN_DNSWL_HI,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 5D5CE1F8C6 for ; Mon, 5 Jul 2021 20:14:22 +0000 (UTC) Received: from localhost ([::1]:46956 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m0Uyz-0001dh-2O for normalperson@yhbt.net; Mon, 05 Jul 2021 16:14:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37898) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m0Uyt-0001bU-0B for bug-gnulib@gnu.org; Mon, 05 Jul 2021 16:14:17 -0400 Received: from zimbra.cs.ucla.edu ([131.179.128.68]:49852) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m0Uyq-0004rx-CE for bug-gnulib@gnu.org; Mon, 05 Jul 2021 16:14:14 -0400 Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id E61AB16008F; Mon, 5 Jul 2021 13:14:09 -0700 (PDT) Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id DWhUUmgmIKqu; Mon, 5 Jul 2021 13:14:09 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 1DE5E1600BB; Mon, 5 Jul 2021 13:14:09 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id y9P_xOcrH4m0; Mon, 5 Jul 2021 13:14:09 -0700 (PDT) Received: from [192.168.1.9] (cpe-172-91-119-151.socal.res.rr.com [172.91.119.151]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id E5C3F16008F; Mon, 5 Jul 2021 13:14:08 -0700 (PDT) To: Florian Weimer References: <20210702023332.2482490-1-eggert@cs.ucla.edu> <878s2ozq70.fsf@oldenburg.str.redhat.com> <4302797.ikRTjI96fm@omega> <87y2akltl7.fsf@oldenburg.str.redhat.com> From: Paul Eggert Organization: UCLA Computer Science Department Subject: Re: [PATCH] year2038: support glibc 2.34 _TIME_BITS=64 Message-ID: <80b0b2e9-fe2d-f11d-7644-058220394237@cs.ucla.edu> Date: Mon, 5 Jul 2021 13:14:08 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <87y2akltl7.fsf@oldenburg.str.redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=131.179.128.68; envelope-from=eggert@cs.ucla.edu; helo=zimbra.cs.ucla.edu X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: bug-gnulib@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Gnulib discussion list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gnulib bugs , Bruno Haible Errors-To: bug-gnulib-bounces+normalperson=yhbt.net@gnu.org Sender: "bug-gnulib" On 7/5/21 7:32 AM, Florian Weimer wrote: > I assume GNU clisp (at least in a full build) need to link to some > system libraries which are not dual ABI (and probably never will be). > If gnulib forces the use of time64 mode, then it creates a push towards > time64 mode in those libraries, too. Only in libraries that expose time_t (or time_t-dependent types like=20 struct timespec and struct stat) directly to their users, right? For=20 example, libselinux is unaffected by this issue even though it calls=20 'lstat' internally, because its user-side ABI is unaffected by time_t wid= th. I take your point, though, that there will be a hassle with libraries=20 whose user-side ABIs depend on time_t width. I expect distros will=20 migrate these libraries and their users to _TIME_BITS=3D64 in an=20 all-or-nothing way. But again, this is not strictly a Gnulib issue. Apps like Coreutils=20 should be fine even with the new Gnulib, as Coreutils doesn't use any of=20 the problematic libraries. Conversely, apps that '#define _TIME_BITS 64'=20 directly and use GLib (or whatever) can have the problem, even if they=20 don't use Gnulib. > It is not, gnulib is pushing things in one particular direction, a > direction that not everyone working on the GNU toolchain agrees with. That's OK; we needn't have universal agreement on this point, which is a=20 good thing because it'd be impractical to insist on universal agreement.=20 There is a way to build with 32-bit time_t even in Gnulib-using apps,=20 so distros wanting to stick with 32-bit time_t can build Gnulib-using=20 apps with the appropriate flags so that they're still living in the=20 32-bit time_t world for now. > There are some major differences to _FILE_OFFSET_BITS=3D64: >=20 > There weren't 20+ years of backwards compatibility in 2005 Not on Linux-based platforms of course, but there were on BSD-based=20 platforms with 20+ years of backwards compatibility back then (SunOS=20 comes to mind). Admittedly there were fewer computers back then but the=20 compatibility issues were quite extensive. > 64-bit file offsets enabled real use cases.=20 Designing devices now, that will be used past 2038, is a real use case.