From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id 2898B198005 for ; Mon, 25 Feb 2013 22:54:05 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id C64CCE08D1; Mon, 25 Feb 2013 22:54:02 +0000 (UTC) Received: from mail-ia0-f175.google.com (mail-ia0-f175.google.com [209.85.210.175]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id E112DE08B5 for ; Mon, 25 Feb 2013 22:54:01 +0000 (UTC) Received: by mail-ia0-f175.google.com with SMTP id r4so2948121iaj.34 for ; Mon, 25 Feb 2013 14:54:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:x-received:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type :content-transfer-encoding; bh=8I5y5Cqf1JwyMu0t4CgBR9AgxST2jcG5Vxq8BPXegDo=; b=DabYsmWeTVSJwU6P/3tQIr5FXa/fF2C3PNH+BBHbimJNfR3U0hg65sQExUriIq39zS /1H0c9RdfrTjhaFYGIgHPhInFTHMuJqV0f5SdTRWnSEoJnii/ocxatH0si2d1yGnHWX7 eNlLcyUkUZ6tvQ39ifXYMUuyzu7+RB2lh0pIVONsgZfutnFBpC/EOKH/PaNVxb+VB0c/ 40DzsDAX9yjv/e8zHw18z5aMuEyMLRZn1FZbMJOsczCzFIv8vTCpL9zAFAL7O41rRfcv JtxPDDFTjxYsL4fSVvvRD9xQzgKYVMdTy6vcDJs5sgTzzxJaR3yQtbyOchuIgQYVre2m h0uw== Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-dev@lists.gentoo.org Reply-to: gentoo-dev@lists.gentoo.org MIME-Version: 1.0 X-Received: by 10.42.60.197 with SMTP id r5mr5174684ich.21.1361832841202; Mon, 25 Feb 2013 14:54:01 -0800 (PST) Sender: freemanrich@gmail.com Received: by 10.64.21.98 with HTTP; Mon, 25 Feb 2013 14:54:01 -0800 (PST) In-Reply-To: <512BE6DB.7090000@flameeyes.eu> References: <20130224230301.20ae2d62@caribou.gateway.2wire.net> <20130225205808.GI1672@wloczykij> <20130225221829.698cc908@gentoo.org> <512BD9B4.5050809@flameeyes.eu> <512BE185.9080605@flameeyes.eu> <512BE6DB.7090000@flameeyes.eu> Date: Mon, 25 Feb 2013 17:54:01 -0500 X-Google-Sender-Auth: -nZCRC9Vol3XQy_i4UE7J-DLFeI Message-ID: Subject: Re: [gentoo-dev] GCC 4.7 unmasking From: Rich Freeman To: gentoo-dev Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Archives-Salt: 534da565-75fd-4a8d-abe7-ceac9caaddf1 X-Archives-Hash: 39c837042265a3751ce6ce0e07bc5608 On Mon, Feb 25, 2013 at 5:34 PM, Diego Elio Petten=F2 wrote: > No, an example of _how building a whole package with -ffast-math_ was > brought up, and you turned it into "something that it should apply to" > (which is false, and stupid to say). Perhaps this is part of the issue then. I didn't not read that email and get the impression that the whole package was being built against that flag. If it ever worked I'd be quite impressed (and it would likely be because the build system ignored it most of the time anyway). If that really was the example, then I can understand why my referencing it suggested that I supported this kind of use of the flag. > Software does not work like a single equation. Ever heard of fuzzing? > You know why it works? Because a single different bit can have cascade > effects. Hadn't really thought of it that way, but it makes sense. Propagation of error applies to random error when applied to integrable functions. That breaks down as soon as you stick an if() in your code. But hey, fractals are pretty... Rich