From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from zimbra.cs.ucla.edu (zimbra.cs.ucla.edu [131.179.128.68]) by sourceware.org (Postfix) with ESMTPS id 4F646386F47A for ; Tue, 9 Mar 2021 19:33:41 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 4F646386F47A Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=cs.ucla.edu Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=eggert@cs.ucla.edu Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 64BC31600D1; Tue, 9 Mar 2021 11:33:40 -0800 (PST) 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 lIAGjyK07Ok6; Tue, 9 Mar 2021 11:33:39 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 71FE71600D4; Tue, 9 Mar 2021 11:33:39 -0800 (PST) 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 L5yb4t9ZEHCm; Tue, 9 Mar 2021 11:33:39 -0800 (PST) Received: from [192.168.1.9] (cpe-23-243-218-95.socal.res.rr.com [23.243.218.95]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 2CAD31600D1; Tue, 9 Mar 2021 11:33:39 -0800 (PST) To: shwaresyst , eblake@redhat.com, bruno@clisp.org, cbouchar@redhat.com, bug-m4@gnu.org, libc-alpha@sourceware.org, austin-group-l@opengroup.org References: <832918739.1734727.1615306471320.ref@mail.yahoo.com> <832918739.1734727.1615306471320@mail.yahoo.com> From: Paul Eggert Organization: UCLA Computer Science Department Subject: Re: SIGSTKSZ is now a run-time variable Message-ID: Date: Tue, 9 Mar 2021 11:33:38 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <832918739.1734727.1615306471320@mail.yahoo.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, NICE_REPLY_A, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Mar 2021 19:33:45 -0000 On 3/9/21 8:14 AM, shwaresyst via Libc-alpha wrote: > The question becomes whether glibc is in violation of POSIX for having > made the change, I don't see how that would be. Apps must define _SC_SIGSTKSZ_SOURCE or=20 _GNU_SOURCE to get the new API, which means the apps do not want strict=20 POSIX conformance anyway. > or whether POSIX needs to be amended to allow SIGSTKSZ > to be non-preprocessor-safe and/or non-constant. That would be a good idea, yes. > I've now seen reports of several > projects failing to build when using glibc with this change included. Yes. I just now checked, and Emacs appears to have this problem so I=20 installed a patch[1] to Emacs, which should fix it. I'm not surprised=20 that other packages have similar issues, and would need similar patches.=20 Gnulib was fixed to avoid this problem in October - before that, Gnulib=20 didn't even conform to POSIX, because it used SIGSTKSZ in #if. The=20 Gnulib patch[2] illustrates other portability messes in this area. [1]=20 https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=3Df97e07ea807cc6d3= 8774a3888a15091b20645ac6 [2]=20 https://git.savannah.gnu.org/cgit/gnulib.git/commit/?id=3Df9e2b20a12a230e= fa30f1d479563ae07d276a94b