From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 18589 invoked by alias); 13 Jan 2014 18:17:07 -0000 Mailing-List: contact libc-ports-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: libc-ports-owner@sourceware.org Received: (qmail 18577 invoked by uid 89); 13 Jan 2014 18:17:06 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.8 required=5.0 tests=AWL,BAYES_00,FAKE_REPLY_C,SPF_SOFTFAIL autolearn=no version=3.3.2 X-HELO: cheddar.halon.org.uk Received: from cheddar.halon.org.uk (HELO cheddar.halon.org.uk) (217.10.144.130) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Mon, 13 Jan 2014 18:17:05 +0000 Received: from bsmtp by cheddar.halon.org.uk with local-bsmtp (Exim 4.80) (envelope-from ) id 1W2m4L-0001zr-Kb; Mon, 13 Jan 2014 18:17:01 +0000 Received: from stemci01 by e102122-lin.cambridge.arm.com with local (Exim 4.80) (envelope-from ) id 1W2m3o-0005ts-Hm; Mon, 13 Jan 2014 18:16:28 +0000 Date: Mon, 13 Jan 2014 18:17:00 -0000 From: Steve McIntyre To: libc-ports@sourceware.org Cc: Andrew Pinski , Marcus Shawcroft , carlos@redhat.com Subject: Re: [PATCH] [AArch64] Define BE loader name. Message-ID: <20140113181623.GW8293@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52CDD48A.80009@redhat.com> X-attached: none User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes X-SW-Source: 2014-01/txt/msg00035.txt.bz2 [ I hope this threads OK - replying to the thread using the list archives... ] Carlos wrote: > >We need technical arguments from both sides to reach consensus. > >Marcus has to come up with real reasons for needing the new dynamic >linker name. Carlos already contributed to a ML discussion that happened after Linaro Connect in November last year, where we had broad consensus from the distros about separating the dynamic linker names for BE and LE systems: http://lists.linaro.org/pipermail/cross-distro/2013-November/000570.html As a background to that, I'm the team lead for Big Endian work in the Linaro Networking Group (LNG). For a variety of reasons we're working on supporting both BE and LE code on a single system and we're investigating various options. Yes, it's a *horrible* idea but there are people who really want to use this. I can envisage places where we may want to have have both BE and LE binaries co-existing in the same system, and it would be nice if that's not locked out here. I'll be honest: I *don't* think that the general purpose Linux distros are likely to care about BE ARM or AArch64 systems in the same way as us, but who knows what might come up? >Andrew, you need to come up with concrete reasons for not wanting to >use a symlink or a copy. > >This is *exactly* the same kind of change we made for the 32-bit ARM >hard-float dynamic linker name change. Yup, Been there, done that. In future, would it not make sense in general to try and keep dynamic linkers separated by default? >The only wrinkle is that a symlink doesn't actually work: >https://sourceware.org/ml/libc-alpha/2012-10/msg00670.html > >If Markus is suggesting using a symlink he'll have to look into the >problem I posted, because the last time I checked the symlink setup >didn't work and required a hack to be used until all binaries had >been migrated. Yup. :-( I remember the hack I came up with, and I've pointed Marcus at it to help him understand what we did and why: http://anonscm.debian.org/viewvc/pkg-glibc/glibc-package/trunk/debian/patches/arm/local-soname-hack.diff?view=markup >Thankfully in the case of the hard-float dynamic linker name change >we had consensus that the name change was needed to support a mixed >environment. Right. Cheers, -- Steve McIntyre steve.mcintyre@linaro.org Linaro.org | Open source software for ARM SoCs