From owner-freebsd-current@FreeBSD.ORG Thu Aug 15 19:30:59 2013 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id D8790E4E; Thu, 15 Aug 2013 19:30:59 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 32C8624ED; Thu, 15 Aug 2013 19:30:58 +0000 (UTC) Received: from tom.home (kostik@localhost [127.0.0.1]) by kib.kiev.ua (8.14.7/8.14.7) with ESMTP id r7FJUn7i012855; Thu, 15 Aug 2013 22:30:49 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.8.3 kib.kiev.ua r7FJUn7i012855 Received: (from kostik@localhost) by tom.home (8.14.7/8.14.7/Submit) id r7FJUnn9012853; Thu, 15 Aug 2013 22:30:49 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Thu, 15 Aug 2013 22:30:49 +0300 From: Konstantin Belousov To: Dimitry Andric Subject: Re: building i386 world on amd64 host: failed @svn Message-ID: <20130815193049.GU4972@kib.kiev.ua> References: <17A40261-A0DA-4070-990F-0D0777A5BE44@FreeBSD.org> <20130815183640.GR4972@kib.kiev.ua> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="MHqfkqUQ5gNQyfXO" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no version=3.3.2 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on tom.home Cc: "freebsd-current@freebsd.org CURRENT" , Dmitry Morozovsky , Peter Wemm X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 15 Aug 2013 19:30:59 -0000 --MHqfkqUQ5gNQyfXO Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Aug 15, 2013 at 09:12:52PM +0200, Dimitry Andric wrote: > On Aug 15, 2013, at 20:36, Konstantin Belousov wrot= e: > > Does the linux box defaults to pentium or higher for -march ? > > 64 bit atomics cannot be implemented in usermode on i386 on > > processors which do not have cmpxchg8b instruction. >=20 > Ah yes, you are totally right, with -v it gives: >=20 > COLLECT_GCC_OPTIONS=3D'-O2' '-S' '-v' '-mtune=3Dgeneric' '-march=3Di586' >=20 > So we should really disable atomics for i486 and lower? Though I have > understood that there also some pentiums without cmpxchg8b... I do not think that there was any Pentium-branded CPU which did not implemented cmpxchg8b. Some late 486 did provided cpuid, but I am almost certain that they did not have cmpxchg8b (cannot check anyway). --MHqfkqUQ5gNQyfXO Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.20 (FreeBSD) iQIcBAEBAgAGBQJSDSxoAAoJEJDCuSvBvK1BpBwP/1BXFf2cYQeggvK5WRW68aWS iofa4yRFqZG2XqgR0WsCMb2Ii306Ry+9BWRMtKDN1CqfDoajwA3QQJjZqNImEJ1D aJ35bf8AHlGVWvqyToLxfSSo/jOEIxlXm4JgPyA56FRAzA07TsxBJ+NxOjPtQ7TH e1c9BNOenKV+DdeuIFgsgFHGrEdlKhAQ4Wxz0WBQxhXar9Gz9Im60q28X1QnNRug CT9oTu8YEIV3lUbUvYvClO47uJyE97IwCZMz6vd2YTmy9al5Ul3+w87HIetGnxct oqywZt1FfDqebwewdqWxj9jXnkGssEFeZ2oCVJjpiccLH/h4Nf3oyOsu46vkgnmC BTBIr/7eZtxQtdXwlNnJQUNj/ptj87yzomXyZxKGejU+01ReoRHG1kYnJCY69/nP m6k8DSUA8hUELdGmQRYrCeBKUZ+Wi6HMyrqRCGEZFDj7wrV36MyUxMJL5JYr2oLL 5BcWv/Sl72KS0hNEZYbzKPzo2mpC4EbM2gCKROhpeMPGpPNT7rNzP59iaqR1qkgm qNDCFhByz90oeuG0j9UvwkUoimFjcKXPFMJROX7MTloOdxkEI1f29wrohWa4+WHI 5DFt8cD7uwBMc9ochNSbOYEyA3bGg1Mh932HokTl7syT1TI0k+Fnm8DXOAKZmDvx xqlmezsuw4Z91LO1vwUa =bQrv -----END PGP SIGNATURE----- --MHqfkqUQ5gNQyfXO--