From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 124658 invoked by alias); 14 Sep 2017 13:43:19 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 124633 invoked by uid 89); 14 Sep 2017 13:43:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.4 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_NONE,RCVD_IN_SORBS_SPAM,SPF_PASS autolearn=no version=3.3.2 spammy= X-HELO: mail-qt0-f177.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=fGiGD2XAlcoC0jq7wIXegkYrxsuCL1MtA0EiItt6xZU=; b=swpLSiXhtL02caXIaYwUJdHR43DAtK62ODmnoJa/DmHhDmdFjCDs+Q6mvAF+RwBXjv ElEIPCuC5DxpGmyFvplQBf32UoQZ+0ozhTJLGKx/hQrG06Plc/xOnFmOBquuW3LENN3R WRoaT3OLN1U+Jozav3nY7s7JlkSLK4QEjO812QHZfeafThmG+vOoMgU0PNacwIMtMlLi 3vcFRtZRytNbPVtlIyZZLJNKabtSiufzrgJBDkrAmleEnokoDFWQq2l624je9jeFKZks jjifjOZ1L0PqKBQ1xh/P79aZTL3lARgHp9UaVbi95/MjQKDei8/oL9/ug+zBOUFhQS9X HIQw== X-Gm-Message-State: AHPjjUiNEbzwOn1CUSv4+dbXWPRxgFzNW/GsSD8MmDTENQADDbBjfgCG gj9ecqMbtA1g1RsPH7eJRw== X-Google-Smtp-Source: AOwi7QDCr9GkiSxkSC0gHaiJFtMSOU+OPqIPJoVkFRf4YhATuKeAb4A3JQTeegc76bECJlAnI4JNWg== X-Received: by 10.200.2.141 with SMTP id p13mr24159431qtg.45.1505396594769; Thu, 14 Sep 2017 06:43:14 -0700 (PDT) Subject: Re: [PATCH 3/9] posix: Allow glob to match dangling symlinks [BZ #866] To: Szabolcs Nagy , Paul Eggert , Zack Weinberg Cc: nd@arm.com, Joseph Myers , Andreas Schwab , GNU C Library References: <1504643122-14874-1-git-send-email-adhemerval.zanella@linaro.org> <1504643122-14874-4-git-send-email-adhemerval.zanella@linaro.org> <878thop5fa.fsf@linux-m68k.org> <9455e298-8c48-c42a-0ec3-ffb8d166c69b@linaro.org> <450d2eab-f21a-f90c-6210-ea638787e339@cs.ucla.edu> <403decc7-e039-9be1-fb44-25d611540156@linaro.org> <7bf58b8a-afc9-b934-9a4a-1616e71c03ff@cs.ucla.edu> <805e4d8a-de63-5253-e214-b3912ed221e3@cs.ucla.edu> <30b5f782-8fb0-5b38-3b4c-6ebf435bc91c@linaro.org> <95745cd2-0033-8a3c-92af-879c24d0d396@cs.ucla.edu> <4e71b51c-3ec8-bb11-19bd-8fc27d4ede3e@linaro.org> <59BA546C.8060904@arm.com> From: Adhemerval Zanella Message-ID: <93a08b16-28a6-2df9-a24e-8f1cc63b7951@linaro.org> Date: Thu, 14 Sep 2017 13:43:00 -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: <59BA546C.8060904@arm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2017-09/txt/msg00616.txt.bz2 On 14/09/2017 07:05, Szabolcs Nagy wrote: > On 13/09/17 13:22, Adhemerval Zanella wrote: >> On 13/09/2017 06:14, Paul Eggert wrote: >>> Adhemerval Zanella wrote: >>>> Another approach that does not involve adding compat symbols (which adds >>>> a lot of code complexity inside glibc build and do not solve 'make' builds >>>> against new glibc) would to make GLOB_ALTDIRFUNCS to follow the old semantic >>>> of using gl_stat instead of gl_lstat while making glob without GLOB_ALTDIRFUNCS >>>> works as intended. And add another flag, GLOB_ALTDIRFUNCS2, which actually >>>> uses gl_lstat. >>> >>> Although that's clever, it is a gratuitous source-code incompatibility with BSD, which is not a good thing. To some extent it's just GLOB_FOLLOW and GLOB_NOFOLLOW in disguise, and disguise is not a good thing in APIs. So I think I still prefer the compat symbol approach. >>> >>> We'll get GNU 'Make' fixed, and I wouldn't worry overly much about people building unpatched 'Make' with new glibc. I filed a Make bug report is here: >>> >>> http://lists.gnu.org/archive/html/bug-make/2017-09/msg00014.html >> >> Right, I am mainly trying to avoid bring more internal glob implementation >> complexity to glibc, but since you says the unpatched 'Make' built >> against newer glibc shouldn't be a problem I think we can this way. >> I will work on it. >> > > i think breaking make is a serious issue now for > anyone trying to do toolchain dev (in native chroots). > and if this gets into a released version of glibc > then it will be an issue for distros. > > i think old make binaries should keep working with > glibc 2.27 whatever it takes and it's best to fix > this breakage sooner than later (it's a pain to > carry patched make around). Yes, that was the consensus and the idea is to provide a compat symbol that does not call gl_lstat. As a side note, make tests itself does not trigger it this issue (running make tests with a newer glibc shows no regression), so it would be good also if make adds a newer tests to stress it. > > (this is not different than the stupid malloc hook > usage was in emacs and that was dragged out over > several years until glibc was fixed to wait for > a stable emacs release that is fixed, the same > should be done for make) >