From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 34003 invoked by alias); 12 Jun 2015 09:38:28 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 33982 invoked by uid 89); 12 Jun 2015 09:38:28 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.4 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY,SPF_HELO_PASS,T_RP_MATCHES_RCVD autolearn=no version=3.3.2 X-Spam-User: qpsmtpd, 2 recipients X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Fri, 12 Jun 2015 09:38:27 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (Postfix) with ESMTPS id 0A2462D1266; Fri, 12 Jun 2015 09:38:26 +0000 (UTC) Received: from localhost (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t5C9cOgO022986; Fri, 12 Jun 2015 05:38:25 -0400 Date: Fri, 12 Jun 2015 09:38:00 -0000 From: Jonathan Wakely To: ramrad01@arm.com Cc: Torvald Riegel , Ramana Radhakrishnan , "gcc-patches@gcc.gnu.org" , "libstdc++@gcc.gnu.org" , Richard Henderson , David Edelsohn , hp@axis.com, Steve Ellcey , Jim Wilson Subject: Re: [Patch libstdc++] Rewrite cpu/generic/atomic_word.h Message-ID: <20150612093824.GA23731@redhat.com> References: <555F14F1.2090504@foss.arm.com> <1432313791.3077.8.camel@triegel.csb> <5576B6D5.5010209@foss.arm.com> <1434059802.15758.5.camel@localhost.localdomain> <20150612090651.GQ12728@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-SW-Source: 2015-06/txt/msg00914.txt.bz2 On 12/06/15 10:30 +0100, Ramana Radhakrishnan wrote: >On Fri, Jun 12, 2015 at 10:06 AM, Jonathan Wakely wrote: >> On 11/06/15 23:56 +0200, Torvald Riegel wrote: >>>> >>>> > On Fri, 2015-05-22 at 12:37 +0100, Ramana Radhakrishnan wrote: >>>> I don't think we can remove _GLIBCXX_READ_MEM_BARRIER and >>>> _GLIBCXX_WRITE_MEM_BARRIER from atomic_word.h even though they are >>>> superseded by the atomics as it is published in the documentation as >>>> available macros. >>> >>> >>> I see. We should at least update the documentation of those, as the >>> current one isn't a really portable specification. If we can, I'd >>> deprecate them. Jonathan, what do you think? >> >> >> Yes, I'm in favour of deprecating them. They are GCC-specific anyway, >> so there is no reason to prefer them to std::atomic_ or __atomic_ >> fences. > >I'll treat it as a follow-up. Sure. >Can I get an ack for this patch though ? I could backport this as is >to fix the problems on ARM / AArch64 (PR target/66200) - alternatively >I'll provide header implementations of the same for the release >branches. Yes, OK for trunk, thanks. I think it's safer if the backport only changes the ARM and AArch64 implementations, at least for now. If no problems are found on trunk we could consider backporting the whole thing for all targets, but it may not be worth it if the other targets are working OK.