From owner-freebsd-current@FreeBSD.ORG Sun Dec 1 04:26:20 2013 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 913D939F for ; Sun, 1 Dec 2013 04:26:20 +0000 (UTC) Received: from mail-vb0-x233.google.com (mail-vb0-x233.google.com [IPv6:2607:f8b0:400c:c02::233]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 3DC001E93 for ; Sun, 1 Dec 2013 04:26:20 +0000 (UTC) Received: by mail-vb0-f51.google.com with SMTP id m10so7526251vbh.38 for ; Sat, 30 Nov 2013 20:26:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wemm.org; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=ZTabH3Zi8LsCFbzvkvR3FxwEmEBJmAmKnnKMBAvWtXE=; b=0clB4P53FA41CfKe53pIfRj0fzP0G1QYFFCARFIG20soKNqCXG60K0U9ojwo40he6B frrPBQ6xlGo4p1fOpa25gWm3TNXl+sh/wOa/+E/Wa9rOuE2AlR90+s05JMF9hZXilEIq B94KCTLYwioWruvrfT8gk/YfjAVNZBlE6XPec= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=ZTabH3Zi8LsCFbzvkvR3FxwEmEBJmAmKnnKMBAvWtXE=; b=gbek/zr3k/wtWylL0ThTD3Y6T2gZ4dKCf5PDusMItYO6P7ipjaCDgjGijRqNKFDkh9 eFtsx7Wo/tVHkJjlvlWkIC1BdRbCt3azG6KwD5rDi83iwora0WwWbbFy3RAo+9P0klws 3zXMXnM2wOZlukWBxicJKNbu1VWAD0r9IVSqkahM9wMAxzEolO3uuQnssi1BHQ1P/O+F PmaX2Vaj/6EBir7w8TCV1dTTS729VxENbBXbPkEO96KdJ/k7OlzG0AwuLyFUomV135LA hugYJV6q/SrrE1VGfdZXznyRjXLBakWrPJub9EE4FGLRTgUENrTC0L1JvQ5n8dXEeSBN 6ttA== X-Gm-Message-State: ALoCoQlDXcvAZH9A0ieE8T4qJjsALGmi2YNbUB8aFneeXARKz9SfZZAoXBZlqQEQaYyK/6kTdEqP MIME-Version: 1.0 X-Received: by 10.221.44.136 with SMTP id ug8mr47474317vcb.13.1385871978635; Sat, 30 Nov 2013 20:26:18 -0800 (PST) Received: by 10.220.167.74 with HTTP; Sat, 30 Nov 2013 20:26:18 -0800 (PST) In-Reply-To: References: <20131130135616.GA59496@kib.kiev.ua> Date: Sat, 30 Nov 2013 20:26:18 -0800 Message-ID: Subject: Re: RFC: (Unconditionally) enable -fno-strict-overflow for kernel builds From: Peter Wemm To: Adrian Chadd Content-Type: text/plain; charset=ISO-8859-1 Cc: Konstantin Belousov , Dimitry Andric , "current@freebsd.org" X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.16 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 01 Dec 2013 04:26:20 -0000 On Sat, Nov 30, 2013 at 4:33 PM, Adrian Chadd wrote: [..] > Are you able to have clang/llvm/gcc tell us where/when code is relying > on undefined behaviour? So we can, like, fix them? It wasn't all that long ago that we had this wonderful thing called -Werror and had a clean kernel build. The problem is that gcc and clang have different warning sets. I seem to recall we had -Werror on for gcc and off for clang. IMHO it would be more useful to do it the other way around. -- Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com; KI6FJV UTF-8: for when a ' just won\342\200\231t do.