From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/6591 Path: news.gmane.org!not-for-mail From: Rich Felker Newsgroups: gmane.linux.lib.musl.general Subject: Re: [PATCH] arm assembly changes for clang compatibility Date: Sat, 22 Nov 2014 16:09:54 -0500 Message-ID: <20141122210954.GD29621@brightrain.aerifal.cx> References: <1415313526-3350676-1-git-send-email-opensource@zhasha.com> <545C92C7.4040703@gentoo.org> <20141107132644.GF22465@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1416690614 8251 80.91.229.3 (22 Nov 2014 21:10:14 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 22 Nov 2014 21:10:14 +0000 (UTC) To: musl@lists.openwall.com Original-X-From: musl-return-6604-gllmg-musl=m.gmane.org@lists.openwall.com Sat Nov 22 22:10:08 2014 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1XsHwV-0005yO-PB for gllmg-musl@m.gmane.org; Sat, 22 Nov 2014 22:10:07 +0100 Original-Received: (qmail 3798 invoked by uid 550); 22 Nov 2014 21:10:06 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 3790 invoked from network); 22 Nov 2014 21:10:06 -0000 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Original-Sender: Rich Felker Xref: news.gmane.org gmane.linux.lib.musl.general:6591 Archived-At: On Sat, Nov 22, 2014 at 09:54:06PM +0100, Joakim Sindholt wrote: > On Fri, 2014-11-07 at 08:26 -0500, Rich Felker wrote: > > On Fri, Nov 07, 2014 at 11:48:05AM +0100, Joakim Sindholt wrote: > > > On Fri, 2014-11-07 at 10:37 +0100, Luca Barbato wrote: > > > > On 06/11/14 23:38, Joakim Sindholt wrote: > > > > > + .word 0xecbc8b10 /* vldmia ip!, {d8-d15} */ > > > > > > > > clang is already notified? > > > > > > > > lu > > > > > > I'm not sure what you mean. There isn't a bug in clang as it will > > > happily accept "vldmia ip!, {d8-d15}". It just won't accept "ldc p11, > > > cr8, [ip], #64" because that's not a legal instruction. Musl just uses > > > it because it aliases to the former and gas won't complain about missing > > > ARM features. > > > > Yes, the problem is that we can't use the official mnemonic because > > the assembler will reject it when the target model lacks fpu, and we > > can't use the generic coprocessor mnemonic because ARM and clang > > intentionally removed support for it. :( > > Any chance of getting this committed or is there more work to be done > and discussions to be had? > > This is the only change needed to get musl working on ARM clang. I think it's okay. It would be nice if we could find something that didn't cause it to get marked as data rather than code in the .o file (e.g. objdump shows it as .word instead of an instruction) but that's not a huge problem if we can't. Since ARM overhaul is a big item for this release cycle I'd like to get all the clang compatibility issues for ARM fixed too. Do you know what clang version has the issue we're working around in arch/arm/syscall_arch.h fixed so I can convert it to a version check (instead of just #ifdef __clang) and start considering a schedule for deprecating support for ancient clang? Rich