From owner-freebsd-current@FreeBSD.ORG Mon May 31 15:03:09 2010 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 753111065672 for ; Mon, 31 May 2010 15:03:09 +0000 (UTC) (envelope-from deischen@freebsd.org) Received: from mail.netplex.net (mail.netplex.net [204.213.176.10]) by mx1.freebsd.org (Postfix) with ESMTP id 18E6C8FC0C for ; Mon, 31 May 2010 15:03:08 +0000 (UTC) Received: from sea.ntplx.net (sea.ntplx.net [204.213.176.11]) by mail.netplex.net (8.14.4/8.14.4/NETPLEX) with ESMTP id o4VF37BR003335 for ; Mon, 31 May 2010 11:03:07 -0400 (EDT) X-Virus-Scanned: by AMaViS and Clam AntiVirus (mail.netplex.net) X-Greylist: Message whitelisted by DRAC access database, not delayed by milter-greylist-4.2.2 (mail.netplex.net [204.213.176.10]); Mon, 31 May 2010 11:03:07 -0400 (EDT) Date: Mon, 31 May 2010 11:03:07 -0400 (EDT) From: Daniel Eischen X-X-Sender: eischen@sea.ntplx.net In-Reply-To: Message-ID: References: <20100529130240.GA99732@freebsd.org> <20100530135859.GI83316@deviant.kiev.zoral.com.ua> <508DA8CE-749A-46B4-AF0B-392DB08CBBCD@samsco.org> <20100531095617.GR83316@deviant.kiev.zoral.com.ua> <71B7DEC2-1ABE-4333-8C8E-02F899D2449B@samsco.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: current@freebsd.org Subject: Re: [TESTING]: ClangBSD branch needs testing before the import to HEAD X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Daniel Eischen List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 31 May 2010 15:03:09 -0000 On Mon, 31 May 2010, Robert Watson wrote: > > I think Kostik's question here is legitimate: clang maturity changes over > time. The earlier we adopt it, the sooner we get the advantages of clang -- > but we also end up being the people who fault in more of the hard-to-diagnose > compiler bugs. Since Kostik fields many of our complex file system/VM/etc > bugs, which are themselves often symptoms of hardware problems rather than > software bugs (a similar class of issue), and is on the release engineering > team, I think he speaks with some authority on the matter. > > I happen to (currently) disagree with him on whether clang is ready for us to > drop in the base system, as I feel providing early access to it (but not > enabling it as the bootstrap by default) will be of significant benefit, but > don't think that delegitimizes the concern he raises. You can burn a lot of > hours chasing software bugs only to eventually (or never) figure out they are > compiler bugs. > > This is the trade-off, but as you point out in your e-mail, there is also a > larger non-technical context. By throwing our weight behind clang, we > benefit in numerous and often non-technical ways: we lend the clang folks an > engaged and technically astute user community who can help them mature their > software, as well as give them a user they community they can point at as > part of establishing their own legitimacy. That engagement in turn means > they will be more responsive to our needs, and it's clear we're at a swing of > the compiler/systems pendulum where we can benefit from the improved compiler > technology we get through using clang. I would like to see this decision made without political bias. Is clangBSD able to support all our architectures? Does it cross build for powerpc, mips, etc? Has it made a ports run and does it successfully build and run most of our ports on Tier-1 archs, and does it compare similarly with gcc for ports on other archs? If it is clearly in a state to entirely replace gcc, then I say import it. But if it is not yet there, and won't be for some time, then I would say leave it out for the time and import it when it can. -- DE