From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 34123 invoked by alias); 21 Sep 2017 16:03:26 -0000 Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org Received: (qmail 34105 invoked by uid 89); 21 Sep 2017 16:03:26 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-3.4 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.2 spammy=Hx-languages-length:1898, H*M:b296 X-Spam-User: qpsmtpd, 2 recipients X-HELO: einhorn-mail.in-berlin.de Received: from einhorn-mail.in-berlin.de (HELO einhorn-mail.in-berlin.de) (217.197.80.20) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 21 Sep 2017 16:03:20 +0000 X-Envelope-From: doko@ubuntu.com Received: from [192.168.178.30] (ip5f5bd693.dynamic.kabel-deutschland.de [95.91.214.147]) (authenticated bits=0) by einhorn.in-berlin.de (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id v8LG1xNM030018 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 21 Sep 2017 18:01:59 +0200 Subject: Re: meaning of "Automatic date update in version.in" commits To: Petr Ovtchenkov , Simon Marchi Cc: Pedro Alves , Matt Rice , Fiodar Stryzhniou , Andreas Schwab , Binutils , Joel Brobecker , GDB References: <20170921135845.479dfc76@void-ptr.info> <024439c7-2083-d368-0138-2160e4494b81@redhat.com> <20170921152240.16bb4cc0@void-ptr.info> <8740f2a7-1300-3116-f34b-5487a8cd8b2b@redhat.com> <20170921161743.3ddc6bb9@void-ptr.info> <20170921184615.6b1e5d44@void-ptr.info> From: Matthias Klose Message-ID: <426b9fdf-a854-6d5f-b296-df71ad0c1561@ubuntu.com> Date: Thu, 21 Sep 2017 16:03:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20170921184615.6b1e5d44@void-ptr.info> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2017-09/txt/msg00082.txt.bz2 On 21.09.2017 17:46, Petr Ovtchenkov wrote: > On Thu, 21 Sep 2017 15:25:53 +0200 > Simon Marchi wrote: > >> On 2017-09-21 15:17, Petr Ovtchenkov wrote: >>> And date stamp in version.in not play here at all. But, >>> >>> - if you insert date stamp into sources, you >>> i) keep "litter" problem >>> ii) make misorientation (what this date mean? commit date? - it >>> already >>> present in commit; and what commit date?) >>> - if you don't insert date stamp into sources, but add to SONAME >>> during build process, >>> it still not reflect ABI compatibilities, but may prevent "binary >>> reproducible builds" >>> (depends upon what date you use). I'm underline, that such addition >>> has no relation to ABI compatibilities, so such SONAME modification >>> lose sense. >> >> Binary reproducible builds mean that if you and I start with the same >> source code and same build tools, we will get exactly the same build >> artifacts. Here the build can't "depend on what date you use": > > If "date stamp" inserted into binary is a build date, then we will have different > binaries. but it not a build date. it is a string taken form a file in the repository. That's exactly what Simon wrote at the end of the last message, and which you ignored to read or comment. Please see below. > If we will use something else, for example "last commit" date, > then we may have "same" build, but may not. From equality of "last commit" date > not follow binary equivalence (consider cherry-picked commit, for example, > or variations of sample "git diff 3110f4be18a2 f625a739" I show above). > >> you >> can't choose a date or another, the date is part of the code you are >> trying to build. So if you and I build from the same commit, we'll >> build using the same date, whatever date is in the version.h file. >> >>