From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-44.mimecast.com (us-smtp-delivery-44.mimecast.com [207.211.30.44]) by sourceware.org (Postfix) with ESMTPS id C7A253858D35 for ; Thu, 25 Nov 2021 18:25:27 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org C7A253858D35 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-21-chwP_gQXMNaowAOp29irSg-1; Thu, 25 Nov 2021 13:25:24 -0500 X-MC-Unique: chwP_gQXMNaowAOp29irSg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 708A0801B10 for ; Thu, 25 Nov 2021 18:25:23 +0000 (UTC) Received: from yselkowitz.remote.redhat.com (unknown [10.22.32.49]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 223E65D740 for ; Thu, 25 Nov 2021 18:25:23 +0000 (UTC) Message-ID: Subject: Re: gnulib m4/threadlib.m4 bug crashing package tests From: Yaakov Selkowitz To: cygwin-apps@cygwin.com Date: Thu, 25 Nov 2021 13:25:22 -0500 In-Reply-To: <04185622-bfb1-9828-a720-716fbdd2e0ab@cornell.edu> References: <04185622-bfb1-9828-a720-716fbdd2e0ab@cornell.edu> User-Agent: Evolution 3.40.4 (3.40.4-2.fc34) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: cygwin.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-3.8 required=5.0 tests=BAYES_00, JMQ_SPF_NEUTRAL, KAM_DMARC_NONE, KAM_DMARC_STATUS, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_NEUTRAL, TXREP autolearn=no autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: cygwin-apps@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin package maintainer discussion list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Nov 2021 18:25:29 -0000 On Thu, 2021-11-25 at 11:26 -0500, Ken Brown via Cygwin-apps wrote: > On 9/29/2021 7:46 PM, Brian Inglis wrote: > > There is a gnulib bug in threadlib.m4 from at least serial 29 to serial > > 31 that incorrectly configures Cygwin support of weak references. > >=20 > > This leads to SIGSEGV stack smashing crashes with no backtrace > > @ 0x00000000100000000 or 0x0000000500000000 etc. normally during tests. > >=20 > > Akim Demaille on bug-bison referred the issue to bug-gnulib where > > Bruno Haible diagnosed and patched the problem to appear in > > m4/threadlib.m4 serial 32: > >=20 > > * m4/threadlib.m4 (gl_WEAK_SYMBOLS): Force a "guessing no" result on > > Cygwin > > https://lists.gnu.org/archive/html/bug-gnulib/2021-09/msg00068.html > > [gl_cv_have_weak=3D"guessing no"] > >=20 > > The patch has now been applied to bison, wget, and wget2, and I have > > attached my patches for the copies in those packages, in case anyone > > else has this issue in their (mainly GNU) packages which may incorporat= e > > by=20 > > inclusion recently updated gnulib m4 macros used in autotools builds. >=20 > Thanks, Brian. >=20 > I'm writing to reinforce this warning.=C2=A0 I just spent 2 days trying t= o debug=20 > mysterious texinfo crashes that were caused by this bug.=C2=A0 I could ha= ve saved > a=20 > lot of time if I had remembered your email and had checked the gnulib > version=20 > being used by texinfo. >=20 > For anyone else who bumps into this, gdb and strace are of no use in > debugging=20 > this crash.=C2=A0 I finally thought to look at the stackdump file, and th= e second > address from the top was in a gnulib file.=C2=A0 That was the key clue. Add gl_cv_have_weak=3Dno to cygconf? --=20 Yaakov