From owner-freebsd-questions@FreeBSD.ORG Tue Mar 2 16:03:36 2010 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6DFCB106566B for ; Tue, 2 Mar 2010 16:03:36 +0000 (UTC) (envelope-from aaron.lewis1989@gmail.com) Received: from mail-ew0-f226.google.com (mail-ew0-f226.google.com [209.85.219.226]) by mx1.freebsd.org (Postfix) with ESMTP id F3B458FC0C for ; Tue, 2 Mar 2010 16:03:35 +0000 (UTC) Received: by ewy26 with SMTP id 26so253087ewy.3 for ; Tue, 02 Mar 2010 08:03:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from :user-agent:mime-version:to:subject:references:in-reply-to :content-type:content-transfer-encoding; bh=Vn0M3taQnYxqv3g6v2ubaDZ7/wZ6cjKHjSKcY7nRI9Y=; b=VKV19flmM0J4Aweg4+RFPsEdG4ee2vLu81igtgB08Ci/drC1RdEbo4PAuK6IYbh00t EvlP2thl9ojKnwZM9AZEdbwDq358JiR2FCfGVF02ubcKb8Gm1jJT0/muz/TbN4okS8P+ 1cxf6jImvhyi3bHWc7DRP4VDQPIdh+VVG21Bw= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:content-type:content-transfer-encoding; b=df1p5unYthUqxRdtJHBtUlj1OKXIZ4m3Q7WJiVQugEmKSqv9mSdBesxfWy92P3PMBF jktrsricBRzGotoqY7nxJqHYWyab66izDWdzXbkNUsaBCyhuFdztkOVdpGEI4LcXaTla b1UxOf6x3fT04Wkg+rnGh1sPk0SvY5N3brL/A= Received: by 10.213.8.6 with SMTP id f6mr1032272ebf.93.1267545810673; Tue, 02 Mar 2010 08:03:30 -0800 (PST) Received: from ?123.233.110.186? ([123.233.110.186]) by mx.google.com with ESMTPS id 13sm3120982ewy.9.2010.03.02.08.03.28 (version=TLSv1/SSLv3 cipher=RC4-MD5); Tue, 02 Mar 2010 08:03:29 -0800 (PST) Message-ID: <4B8D36D8.8070303@gmail.com> Date: Wed, 03 Mar 2010 00:03:36 +0800 From: Aaron Lewis User-Agent: Thunderbird 2.0.0.22 (X11/20090608) MIME-Version: 1.0 To: freebsd-questions@freebsd.org References: <997836.8570.qm@web65512.mail.ac4.yahoo.com> In-Reply-To: <997836.8570.qm@web65512.mail.ac4.yahoo.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [SOLVED] Compiler Flags problem with core2 CPU X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Mar 2010 16:03:36 -0000 James Phillips wrote: > I laughed at your question because I remember reading somewhere that using aggressive optimization options is a good way to find compiler bugs. I think that extends of optimizations for "new" CPU architectures as well. > I also heard kernel code avoids MMX instructions for some reason: it may have to do with interrupt handling (fewer registers=faster?). x86 (and AMD64) processors are backwards compatible, so you don't strictly need the latest instructions. > > Regards, > > James Phillips Ah , i've just read it may not be safe to use MMX and SSE instructions in kernel code. So my CFLAGS is much too agressive , i'll notice this. Thank you all. -- Best Regards, Aaron Lewis - PGP: 0xA476D2E9 irc: A4r0n on freenode