From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH] ARM: Blacklist GCC 4.8.0 to GCC 4.8.2 - PR58854 Date: Sun, 19 Oct 2014 10:55:55 +0100 Message-ID: <20141019095555.GU12379@n2100.arm.linux.org.uk> References: <543EF2B6.1050009@hurleysoftware.com> <20141016001801.GQ12379@n2100.arm.linux.org.uk> <20141017134112.GS12379@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from gw-1.arm.linux.org.uk ([78.32.30.217]:37724 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751469AbaJSJ4J (ORCPT ); Sun, 19 Oct 2014 05:56:09 -0400 Content-Disposition: inline In-Reply-To: <20141017134112.GS12379@n2100.arm.linux.org.uk> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Nicolas Pitre , Olof Johansson Cc: Peter Hurley , Otavio Salvador , Nathan Lynch , David Laight , Linux OMAP Mailing List , Linus Torvalds , linux-arm-kernel@lists.infradead.org On Fri, Oct 17, 2014 at 02:41:12PM +0100, Russell King - ARM Linux wrote: > On Thu, Oct 16, 2014 at 10:58:06AM -0400, Nicolas Pitre wrote: > > On Thu, 16 Oct 2014, Russell King - ARM Linux wrote: > > > > > So, let me put this another way: a compiler with this bug is _completely_ > > > unsuitable for use for compiling programs for use under the Linux > > > kernel _as well_ as the Linux kernel itself. > > > > > > The difference is that the Linaro compilers come with an expectation > > > that they are usable on ARM... whereas stock versions cover a lot more > > > and so the ARM arch is probably very small number of their users. > > > > > > Hence why I recommend that Linaro takes down their buggy compiler. > > > Their 4.8.3 version should not be used *anywhere*, just the same as > > > the stock 4.8 to 4.8.2 inclusive should also not be used anywhere on > > > ARM either. > > > > Here's the answer from the toolchain team: > > > > On Thu, 16 Oct 2014, Yvan Roux wrote: > > > > | Hi Nicolas, > > | > > | thanks for bringing this to our knowledge. > > | > > | The fix for PR58854 was included in our releases since the GCC > > | 4.8-2013.12 which is based on a 4.8.3 prerelease version (at svn > > | revision 205577). As we are doing monthly releases based on a > > | revision of the related FSF branch, using GCC_VERSION (__GNUC__, > > | __GNUC_MINOR,__GNUC_PATCHLEVEL) is not accurate enough to identify the > > | release version (all our releases between November 2013 and May 2014 > > | will be 4.8.3) the __VERSION__ predefined macro is a bit more accurate > > | here ("4.8.3 20131202 (prerelease)") but not completely satisfactory. > > | > > | I completely agree that we should at least mention in our impacted > > | releases download pages that this bug is present. > > Unfortunately, __VERSION__ doesn't help us identify that the bug has > been fixed - it's not something which can be tested at preprocessor > time. > > Those which identify themselves as 4.8.3 won't be impacted by the patch, > which means that the Linaro 4.8.3 GCC versions will continue to build > the kernel just fine. Even the buggy versions. > > I don't see the point of continuing to offer the buggy versions for > download though - the compiler is totally unsuitable for building any > Linux related binaries, be that kernel or userspace, and so should not > be used under any circumstances, period. Right, with the test fixed (&& instead of ||), I've just pushed it out this morning, and received the results from Olof's kernel builder, which shows that he's using a gcc 4.8.x version which gets caught by the test. I think Olof needs to do something about his gcc version there. -- FTTC broadband for 0.8mile line: currently at 9.5Mbps down 400kbps up according to speedtest.net.