From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 9B6CE449D0 for ; Mon, 31 Oct 2022 13:03:33 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 28D7668BE28; Mon, 31 Oct 2022 15:03:30 +0200 (EET) Received: from mail0.khirnov.net (red.khirnov.net [176.97.15.12]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 21E2E68BCD2 for ; Mon, 31 Oct 2022 15:03:24 +0200 (EET) Received: from localhost (localhost [IPv6:::1]) by mail0.khirnov.net (Postfix) with ESMTP id A20A02404E4; Mon, 31 Oct 2022 14:03:23 +0100 (CET) Received: from mail0.khirnov.net ([IPv6:::1]) by localhost (mail0.khirnov.net [IPv6:::1]) (amavisd-new, port 10024) with ESMTP id TVkGiMgG8nbi; Mon, 31 Oct 2022 14:03:21 +0100 (CET) Received: from lain.khirnov.net (lain.khirnov.net [IPv6:2001:67c:1138:4306::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "lain.khirnov.net", Issuer "smtp.khirnov.net SMTP CA" (verified OK)) by mail0.khirnov.net (Postfix) with ESMTPS id 0D35D2400F4; Mon, 31 Oct 2022 14:03:21 +0100 (CET) Received: by lain.khirnov.net (Postfix, from userid 1000) id 262811601B2; Mon, 31 Oct 2022 14:03:21 +0100 (CET) From: Anton Khirnov To: FFmpeg development discussions and patches In-Reply-To: References: <20221028182333.GJ4048598@pb2> <20221030201007.GD1814017@pb2> Mail-Followup-To: FFmpeg development discussions and patches , Jan Engelhardt , Andreas Schneider Date: Mon, 31 Oct 2022 14:03:21 +0100 Message-ID: <166722140107.12287.4175132527138383610@lain.khirnov.net> User-Agent: alot/0.8.1 MIME-Version: 1.0 Subject: Re: [FFmpeg-devel] FFmpeg 5.0 X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: Jan Engelhardt , Andreas Schneider Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: Quoting Neal Gompa (2022-10-30 22:04:42) > On Sun, Oct 30, 2022 at 4:10 PM Michael Niedermayer > wrote: > > > > On Sat, Oct 29, 2022 at 02:29:56PM -0400, Neal Gompa wrote: > > > On Fri, Oct 28, 2022 at 2:23 PM Michael Niedermayer > > > wrote: > > > > > > > > Hi > > > > > > > > According to our > > > > https://trac.ffmpeg.org/wiki/Downstreams > > > > > > > > Noone and nothing is using 5.0 > > > > should i make another release of 5.0 ? > > > > should i move 5.0 to olddownloads ? > > > > > > > > does anyone use it ? plan to use it or know of someone using it ? > > > > > > > > > > Fedora 36 still uses FFmpeg 5.0 as I discovered there was an ABI break > > > that made upgrading to FFmpeg 5.1 not possible for F36. FFmpeg 5.1 is > > > used for Fedora 37, though. > > > > > > This had apparently been also discovered by openSUSE some time ago: > > > https://build.opensuse.org/package/view_file/multimedia:libs/ffmpeg-5/work-around-abi-break.patch?expand=1 > > > > You can replace 5.0 by 5.1 but not 5.1 by 5.0, The compatibility is only > > in one way. > > Iam assuming here you talk about the addition of functions and there is > > not some other issue iam not aware of. > > > > My understanding is that when using symbol versions, modifying the > symbol table creates a breakage on its own. Do you have some authoritative source for this claim? So far all the arguments I've seen were along the lines of "because I say so". > > > > > > Do we have ABI testing in place for submitted patches? I haven't seen > > > any evidence of CI testing of patches submitted to the mailing list, > > > but maybe I'm looking in the wrong place? If there is, maybe we can > > > consider adding some kind of ABI testing for release branches, using > > > tools like libabigail[1] with abidiff[2]? > > > > > > [1]: https://sourceware.org/libabigail/ > > > [2]: https://www.mankier.com/1/abidiff > > > > iam not sure there is agreement between you and others of what is a ABI break > > so the tool maybe will not help. > > > > I have generaly done testing with replacing old libraries by new when doing > > releases. But for me a ABI break is if replacing a library by another breaks > > some binary that is not rebuild and linked to the new lib. > > > > More testing is always good and welcome of course. > > > > Yeah, I think that qualifying how ABI is validated in a reproducible > way would be useful. The abigail tooling can help here, In Fedora, > every update runs through abigail validation too. I vaguely recall > that it warned me when I did the update in Rawhide, which is how I wound > up talking to Jan in openSUSE and RPM Fusion maintainers, who both > didn't refresh FFmpeg on stable branches with 5.0 to 5.1. > > It's also entirely possible that I was *too* cautious, and I'm okay > with having a conversation that leads me to do differently in the future. Having automated ABI testing would be definitely a good idea, not all developers understand how ABI compatibility works and there have been breakages (according to our definition) recently. I also have https://github.com/lvc/abi-compliance-checker/ on my to-look-at list, but as always time is lacking. -- Anton Khirnov _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".