From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net (mail-out.m-online.net [IPv6:2001:a60:0:28:0:1:25:1]) by sourceware.org (Postfix) with ESMTPS id 95DC0385B833 for ; Mon, 23 Mar 2020 22:14:44 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 95DC0385B833 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=denx.de Authentication-Results: sourceware.org; spf=none smtp.mailfrom=lukma@denx.de Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 48mTFb5vd7z1rsqV; Mon, 23 Mar 2020 23:14:43 +0100 (CET) Received: from localhost (dynscan1.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 48mTFb5SwXz1qyDd; Mon, 23 Mar 2020 23:14:43 +0100 (CET) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id DI_S4ujKSmNg; Mon, 23 Mar 2020 23:14:42 +0100 (CET) X-Auth-Info: 9Z9+WqUrZ6HIaxIFXjreibnDA2QUdPVKAR5ez2ULhwA= Received: from jawa (85-222-111-42.dynamic.chello.pl [85.222.111.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Mon, 23 Mar 2020 23:14:42 +0100 (CET) Date: Mon, 23 Mar 2020 23:14:41 +0100 From: Lukasz Majewski To: Joseph Myers Cc: , Florian Weimer , Adhemerval Zanella Subject: Re: Question regarding __clock_gettime symbol visibility across glibc build Message-ID: <20200323231441.1532a2b4@jawa> In-Reply-To: References: <20200317084724.6df11fb1@jawa> <20200321080040.7ac91d19@jawa> Organization: denx.de X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; boundary="Sig_/3i84U0u4_aO_XZ1q0RzSe/v"; protocol="application/pgp-signature" X-Spam-Status: No, score=-1.6 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=no 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-help@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-help mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 23 Mar 2020 22:14:46 -0000 --Sig_/3i84U0u4_aO_XZ1q0RzSe/v Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi Joseph, > On Sat, 21 Mar 2020, Lukasz Majewski wrote: >=20 > > > /work/lukma/glibc/glibc-many-build/src/glibc/malloc/memusage.c:181: > > > undefined reference to `__clock_gettime64' =20 >=20 > I.e. __clock_gettime64 is not exported at any symbol version in the=20 > dynamic symbol table of libc.so. >=20 > Any symbol defined in libc.so and used in another glibc shared > library or executable needs to be exported at some symbol version in > some Versions file. In the case of symbols for 64-bit time, it > should be exported at version GLIBC_PRIVATE until we're ready to > support _TIME_BITS=3D64 in the headers, at which point all such symbols > should be exported at the version of the next glibc release and be > removed from GLIBC_PRIVATE if there. And the penny has dropped. The __clock_gettime64 indeed is not exported in the current glibc. It is exported with my patches for Y2038 support. I will export __clock_gettime64 in this patch series. Big thanks for the explanation. >=20 > > > nm > > > ./work/glibc/glibc-many-build/build/glibcs/arm-linux-gnueabi/glibc/li= bc.so > > > | grep clock_gettime =20 >=20 > nm uses the static symbol table by default. You need nm -D, objdump > -T (shows symbol versions as well) or readelf --dyn-syms to look at > the dynamic symbol table. >=20 Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de --Sig_/3i84U0u4_aO_XZ1q0RzSe/v Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCgAdFiEEgAyFJ+N6uu6+XupJAR8vZIA0zr0FAl55NNEACgkQAR8vZIA0 zr0Pjwf/T8GUlHwU4O+lBQXdqVQAnh4rzcNyWUxarL9Oc5bMgJ4WbgHdMrmjecWU HjDCo329WdyiccmlXBTex/qYLEk36ftrc8/EONI5uCBOjHXyva5pxtAR4UUITuVV Ac5EW+FVGaUlJDyTr+0zKxfOKAbJ++lKzd+mXUUf4no5BHErNJjAH9EXmNMYkQRO VxEE+5AVD0BDkyXgNdzefrzFsu5hrE+BInLzPAJ4uGXRR63ZwhlkOY0mUEftLPlW FSWzk8Ax2L3cZ5noFGLy2YgcRUgLp666o855ysc7tSs5ZR4eD7AB5ePfjotI+eWn PN+tymbkbWrWP6eMk6ZVCaZXvJiuEQ== =z8zy -----END PGP SIGNATURE----- --Sig_/3i84U0u4_aO_XZ1q0RzSe/v--