From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 101629 invoked by alias); 20 Apr 2016 09:45:35 -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 101594 invoked by uid 89); 20 Apr 2016 09:45:33 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.5 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=expertise, Hx-languages-length:1822, claim, today's X-HELO: mailout1.w1.samsung.com Received: from mailout1.w1.samsung.com (HELO mailout1.w1.samsung.com) (210.118.77.11) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Wed, 20 Apr 2016 09:45:31 +0000 Received: from eucpsbgm1.samsung.com (unknown [203.254.199.244]) by mailout1.w1.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0O5X00MV8F3RSK20@mailout1.w1.samsung.com> for gdb@sourceware.org; Wed, 20 Apr 2016 10:45:27 +0100 (BST) Received: from eusync2.samsung.com ( [203.254.199.212]) by eucpsbgm1.samsung.com (EUCPMTA) with SMTP id 82.11.05254.7BF47175; Wed, 20 Apr 2016 10:45:27 +0100 (BST) Received: from [106.109.9.145] by eusync2.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTPA id <0O5X009P2F3QW070@eusync2.samsung.com>; Wed, 20 Apr 2016 10:45:27 +0100 (BST) Subject: Re: [Bug-readline] [PATCH] Enable visibility annotations To: Pedro Alves , Doug Evans References: <94eb2c1232a01a28910530c65c78@google.com> <57171B67.3040204@samsung.com> <57174A3A.80303@redhat.com> Cc: chet.ramey@case.edu, bug-readline@gnu.org, Vyacheslav Barinov , Yury Usishchev , "gdb@sourceware.org" , Jan Kratochvil From: Yury Gribov Message-id: <57174FBC.7080909@samsung.com> Date: Wed, 20 Apr 2016 09:45:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-version: 1.0 In-reply-to: <57174A3A.80303@redhat.com> Content-type: text/plain; charset=utf-8; format=flowed Content-transfer-encoding: 7bit X-SW-Source: 2016-04/txt/msg00035.txt.bz2 On 04/20/2016 12:22 PM, Pedro Alves wrote: > On 04/20/2016 07:02 AM, Yury Gribov wrote: > >> Pedro, >> >> Do you think the above is doable for gdb? > > I don't know -- I'm already juggling too many balls in the > air, and I'm afraid that if that depends on me, it'll take a > while before I'll manage to try. > > Since gdb's use of private symbols is not an isolated incident, > I don't think we should try to clean up all packages that make > use of private symbols, in a rush. Instead, I think readline > needs to take a staged approach: > > - Export all the private symbols that programs are using today. > Simply accept today's reality. The dynamic symbol table of > libreadline.so still shrinks, precedent for visibility > annotations is still set, and private symbol leakage > is contained, because future software will no longer be > able to abuse all the other private symbols that are > not exported. Agreed, that's my plan for now. > - Claim that the symbols may no longer be available in a > future release. You mean just email respective package maintainers? > - Give time for packages to clean themselves up, and propose > any necessary new replacement APIs. This would require significant expertise in readline though... > - Optionally, in the release after the next, mark the symbols > as deprecated with __attribute__((deprecated)), so packages > that abuse private symbols get a build-time warning. That won't help as these symbols are not present in headers anyway. All users have their own private declarations. > - In some future release, stop exporting the symbols. > >> That would of course leave the >> problem of linking older gdb with new readline which will need to be >> resolved by distros. > > Right. > > Thanks, > Pedro Alves