From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1QjpT5-0004tp-2U for garchives@archives.gentoo.org; Thu, 21 Jul 2011 09:22:56 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id ACA4A21C1FB; Thu, 21 Jul 2011 09:22:42 +0000 (UTC) Received: from out5.smtp.messagingengine.com (out5.smtp.messagingengine.com [66.111.4.29]) by pigeon.gentoo.org (Postfix) with ESMTP id 94CD221C0E4 for ; Thu, 21 Jul 2011 09:21:35 +0000 (UTC) Received: from compute6.internal (compute6.nyi.mail.srv.osa [10.202.2.46]) by gateway1.messagingengine.com (Postfix) with ESMTP id 42BFE20537 for ; Thu, 21 Jul 2011 05:21:35 -0400 (EDT) Received: from frontend1.messagingengine.com ([10.202.2.160]) by compute6.internal (MEProxy); Thu, 21 Jul 2011 05:21:35 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=message-id:date:from:mime-version:to :subject:references:in-reply-to:content-type; s=smtpout; bh=5Ejr QS1KcMge7mBM/Hc7fk7cXk8=; b=NLVHzzvPCtTCAT7xNbzbXlqhmo+JjId6Qo8X pbHfVIV6ZMbTtm2YDmgibtSjzywgN4A8LJdtY/kU5QYhrZgq0ru2eBfuBmWt+okY 0tRG13+FHIwrcOP9GtZvTiPlHcnGyRDtrl/od5rcYw1i7xFSAq/hzkc50zO+4bpn RMJ+wCA= X-Sasl-enc: y8axZExfEi7n0iKHI9DX7l+m5wUz2S41xbihejNlvVJ6 1311240092 Received: from [192.168.5.18] (serv.binarywings.net [83.169.5.6]) by mail.messagingengine.com (Postfix) with ESMTPSA id 76E4640B927 for ; Thu, 21 Jul 2011 05:21:32 -0400 (EDT) Message-ID: <4E27EF91.4060408@binarywings.net> Date: Thu, 21 Jul 2011 11:21:21 +0200 From: Florian Philipp User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110507 Lightning/1.0b3pre Thunderbird/3.1.10 Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] New computer and Gentoo References: In-Reply-To: X-Enigmail-Version: 1.1.2 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigAF8D2408C7BE779937E3208A" X-Archives-Salt: X-Archives-Hash: 8831201ed31de682865c3fe5c789b298 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigAF8D2408C7BE779937E3208A Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Am 21.07.2011 10:57, schrieb Pandu Poluan: > -original message- > Subject: Re: [gentoo-user] New computer and Gentoo > From: Bill Kenworthy > Date: 2011-07-21 12:54 >=20 >> On Thu, 2011-07-21 at 06:26 +0100, Mick wrote: [...] >> Ive just stumbled on something weird with march=3Dnative: >> >> At some point I had march=3Dprescott on a core2 E4600 running 32bit - >> worked well. Changed to march=3Dnative and did some upgrades with a f= ew >> odd things like asterisk segfaulting in a glibc library afterwards, an= d >> some things not building. Then to add confusion, I changed to an >> pentium Duo E6600 (flies!) and added another stick of ram. More odd >> things happening such as reiserfs oopsing on shutdown. >> >> Last night the penny dropped and I looked the new processor up and >> changed to march=3Dcore2 and have mostly corrected (recompiled) the >> damage. >> >> So not sure about march=3Dnative now as it is only what was built with= >> native thats been problematic. With 20-20 hindsight it was perhaps >> predictable ... >=20 > IMO you're not supposed to compile part of the system with -march=3D > and the rest with -march=3Dnative. The instructions (and optimizations)= > emitted by -march=3Dnative might not be compatible with your previous > -march. I'd like to see a reference for this claim. -march=3Dnative doesn't do more than set -march=3Dcore2 and some other optimizations for cache size etc. This should be no more troublesome than mixing code compiled with different specific -march settings. When you look at binary distributions (and especially precompiled packages from the developer instead of the distribution), this is pretty much normal. The compiler is not allowed to change the external interfaces of functions for optimization purposes (see [1]). Besides this, I can only think of alignment problems ([2]) but even this should be handled correctly by the compiler. Everything else is a compiler bug that should be reported. [1] http://en.wikipedia.org/wiki/Calling_convention [2] http://en.wikipedia.org/wiki/Data_alignment Regards, Florian Philipp --------------enigAF8D2408C7BE779937E3208A Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk4n75YACgkQqs4uOUlOuU8KjQCeNUBtvsw2C8WnzpgNR1GtWM2f 87wAnREcVoYj4AukpHGckdH+ZPcbglwP =kENd -----END PGP SIGNATURE----- --------------enigAF8D2408C7BE779937E3208A--