From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 66CCE138334 for ; Fri, 14 Sep 2018 00:55:02 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 15CDBE0D0D; Fri, 14 Sep 2018 00:54:59 +0000 (UTC) Received: from mail-qt0-x229.google.com (mail-qt0-x229.google.com [IPv6:2607:f8b0:400d:c0d::229]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id B7BA2E0A5A for ; Fri, 14 Sep 2018 00:54:58 +0000 (UTC) Received: by mail-qt0-x229.google.com with SMTP id z8-v6so7260187qto.9 for ; Thu, 13 Sep 2018 17:54:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:subject:from:to:date:mime-version :content-transfer-encoding:user-agent:in-reply-to:references; bh=XnlYR2dYCBp7STAQEjQYL9CbwxcGf8ziEcmHwCiTxN4=; b=Eb+ApSJWD3wdU/wDYy6VwMa6yBq4tQaJNDCWPxtkJSjfIMk6jRj5+3XAHD3KMnFRn+ WGF1vcI6Yfa7DrXusSPJUeXc8q7zbdy+AWTPIppRJgTklYET92ZlbKQDihv4VH4zf9d4 BIjfGGg+g4jTPoKgMqQjipcnNToHnMFuJnlAvIyHSCJlhv+rxQGPKvjocByJR8hwqzyJ +IneSbkHeDc58oOZ2eYj7tDk+N8TkAW65HGgYn8YI09qFvJOX2iG4O9nJeTXKKtHGGlO GRGgDZVoaqq2ISrKMztU55VoCT26eHjBLddW32k7ROsxEIS77hQ2wtxMf42ycnog5nvR GnmA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:subject:from:to:date:mime-version :content-transfer-encoding:user-agent:in-reply-to:references; bh=XnlYR2dYCBp7STAQEjQYL9CbwxcGf8ziEcmHwCiTxN4=; b=uHMvtFAxJ5M+LnLXl+wgWEGXwrQk5G37kWrMptc7J00bQQiztMUcqtXy7OUEJzT8EQ QXQPk7c51YSyH0ZaXTTTosKlAx+sERfWZ1G9QIqms0giRSu38WhS08yqtUuvWQL8TR74 qHduwkkFKASPTDi5Op6zvVLE0b58tABCuWXzD7saesAOHKr7e9MQ4xivdFSNVL2x5rOk 1ZSvxKQw0NkGvT5b7IHBqDXQkyCOoCHO37ydnkAC7OySEfk8T/EOeEvUk/N23Xtp+EpD SGkGQtpjvN5HxoaKH6u7/u6IKacWtyjy169bwf66+HmGLLiWLTno5Lwnu6qBVbgE9p41 j/Yg== X-Gm-Message-State: APzg51CR9kPOUt8dRoJXB/pGJV/J0qGxMnJFG6r0FU3M6uvopGHUknnN OIXxYQRMYtLV60sE0P9QEjxbW2SO X-Google-Smtp-Source: ANB0VdZQacjkbhyCe3+Vb5PNZjFQK7zNd7N5HEn2G1x+rWR8wXijy9zMkxyS72/WqpNnUZ0JvzUp1w== X-Received: by 2002:a0c:d788:: with SMTP id z8-v6mr7449537qvi.71.1536886497189; Thu, 13 Sep 2018 17:54:57 -0700 (PDT) Received: from thinkpad (pool-72-89-51-102.nycmny.fios.verizon.net. [72.89.51.102]) by smtp.gmail.com with ESMTPSA id z123-v6sm3609878qke.68.2018.09.13.17.54.55 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 13 Sep 2018 17:54:55 -0700 (PDT) Message-ID: <5b9b06df.1c69fb81.11923.7dc6@mx.google.com> X-Google-Original-Message-ID: <13092018.085457417пп%l6PltA7EA0iNfevN8K8iA/i9BHk=%0xd34df00d@gmail.com> Subject: Re: [gentoo-dev] Changing policy about -Werror From: "Georg Rudoy" <0xd34df00d@gmail.com> To: "" Date: Thu, 13 Sep 2018 20:54:57 -0400 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 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable User-Agent: LeechCraft Snails 0.6.70-11938-g96e79e4c7b In-Reply-To: <3A8A39E8-91DF-40B2-8958-F046FA58622B@gentoo.org> References: <20180909143221.21d784d02f51623e8c57c545@gentoo.org> <1536510660.863.9.camel@gentoo.org> <20180910074539.GA6512@baraddur.perfinion.com> <0d8b7f02-9c38-969c-413b-69d4dee6ca89@gentoo.org> <20180912085649.GA16516@baraddur.perfinion.com> <6c18c6bd-4cf3-dff6-2f20-c021063e01fa@gentoo.org> <20180913160347.GC26329@gentoo.org> <4FCF42AC-6B48-40F6-8B98-79CF71789A6A@gentoo.org> <3A8A39E8-91DF-40B2-8958-F046FA58622B@gentoo.org> X-Archives-Salt: 7738d003-dac5-4fb6-96b7-82f18cd23370 X-Archives-Hash: d2ce57b8ca996cac42183b8e53c257be On 14.09.2018 at 0:44 user Richard Yao wrote: > This is a really odd design decision by the GCC developers. With other = compilers, the separation between front end and backend is strong enough = that you will never have this sort of thing. It does not seem necessary t= o me either. :/ You might be able to perform certain additional data/control flow analysi= s after things like inlining, dead code removal or devirtualization. Moving that logic to the frontend would require essentially duplicating w= hat's the optimizer's gonna do anyway, which might have negative effects = on compilation times (both with and without optimizations) and compiler c= ode maintenance. BTW I'm not sure the separation on backend/frontend makes sense for moder= n C++ compilers. clang surely does some optimizations, and llvm (at least= , in theory) is certainly able to find certain issues after more optimize= r passes. --=20 Georg Rudoy