Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751201AbaKXXq6 (ORCPT ); Mon, 24 Nov 2014 18:46:58 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42558 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750852AbaKXXq4 (ORCPT ); Mon, 24 Nov 2014 18:46:56 -0500 Message-ID: <5473C362.80308@redhat.com> Date: Mon, 24 Nov 2014 15:46:42 -0800 From: Josh Stone User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Michal Marek , linux-kernel@vger.kernel.org CC: "Frank Ch. Eigler" , Jakub Jelinek , Josh Boyer , Greg Kroah-Hartman , Linus Torvalds , Andrew Morton , Markus Trippelsdorf , =?UTF-8?B?TWljaGVsIETDpG56?= =?UTF-8?B?ZXI=?= Subject: Re: [PATCH RESEND] Kbuild: Add an option to enable GCC VTA References: <1416595200-22359-1-git-send-email-jistone@redhat.com> <5473A74F.8000709@suse.cz> In-Reply-To: <5473A74F.8000709@suse.cz> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/24/2014 01:46 PM, Michal Marek wrote: > Dne 21.11.2014 v 19:40 Josh Stone napsal(a): >> Due to recent codegen issues, gcc -fvar-tracking-assignments was >> unconditionally disabled in commit 2062afb4f804a ("Fix gcc-4.9.0 >> miscompilation of load_balance() in scheduler"). However, this reduces > [...] >> With gcc-4.9.2-1.fc22, I can now build v3.18-rc5 with Fedora's i686 and >> x86_64 configs, and this is completely clean with GCC_COMPARE_DEBUG. > > According to gcc's bug#61801, this is really fixed in 4.9.2 (commit > 556537c4 in the git mirror). So how about checking for this minimal > version instead of a new Kconfig option? That's possible, if the new Kconfig option is really undesirable. But given that there's a similar DWARF4 option, which this pairs well with, I thought a VTA option was a good choice. Besides 4.9.2 though, this particular fix has also been backported to 4.8.4, and who knows what various distro maintainers may do. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/