From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark H Weaver Subject: Re: Gmp test failure on armhf Date: Sat, 04 Jul 2015 03:08:14 -0400 Message-ID: <87ioa04cyp.fsf@netris.org> References: <20150626093215.GA3593@debian> <87d20fsh2z.fsf@gnu.org> <20150703201207.GB26201@debian> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:60148) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZBHYy-0003Q1-98 for guix-devel@gnu.org; Sat, 04 Jul 2015 03:08:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZBHYv-0004nF-3u for guix-devel@gnu.org; Sat, 04 Jul 2015 03:08:36 -0400 In-Reply-To: <20150703201207.GB26201@debian> (Andreas Enge's message of "Fri, 3 Jul 2015 22:12:07 +0200") List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org To: Andreas Enge Cc: guix-devel@gnu.org Andreas Enge writes: > On Sun, Jun 28, 2015 at 10:39:32PM +0200, Ludovic Court=C3=A8s wrote: >> Could you post the relevant excerpt of the build log, or >> =E2=80=98test-suite.log=E2=80=99? > > Well, I tried to build it by hand, and it worked; then I tried again with > a recent git version, and it also worked. > > Since I noticed a "FIXME" in the gmp package, I worked on that. The > attached patch backports a fix to config.guess in the gmp trunk that=20 > correctly detects the neon architecture on multicore arm machines, instead > of explicitly passing the build triplet. We shouldn't be using config.guess anyway, because we shouldn't be compiling packages specialized for the build machine, at least not by default. A while back on IRC, Ludovic agreed to my proposal to pass --build to configure by default in gnu-build-system, a change to be made hopefully in the next core-updates cycle. After that, config.guess will not be used. As for NEON, I had originally followed Debian's armhf decision to compile code that doesn't require NEON support, but have since changed my mind about that. It seems that the Debian porters made that decision to support a couple of hardware devices that may have been important at the time, but that time has passed. I've since learned that NEON is a common target for modern highly optimized ARM assembly code, and that we should assume it as a baseline. This is another change that I think we should make in the next core-updates cycle. To give credit where credit is due: John Darrington chose to target NEON in his initial patches for Guix armhf. If we make these changes, then I think this patch is superfluous, right? Mark