From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/11292 Path: news.gmane.org!.POSTED!not-for-mail From: Florian Weimer Newsgroups: gmane.linux.kernel.api,gmane.linux.kernel,gmane.linux.lib.musl.general Subject: Re: [PATCH resent] uapi libc compat: allow non-glibc to opt out of uapi definitions Date: Tue, 25 Apr 2017 15:22:00 +0200 Message-ID: <1d9ab212-6c80-f7fa-4be5-87b567ada949@redhat.com> References: <20161111120820.GA435@nyan> <20170309001435.GJ2082@port70.net> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: blaine.gmane.org 1493126527 21346 195.159.176.226 (25 Apr 2017 13:22:07 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 25 Apr 2017 13:22:07 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.0 To: Carlos O'Donell , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "David S. Miller" , linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, musl-ZwoEplunGu1jrUoiu81ncdBPR1lH4CV8@public.gmane.org, Rich Felker Original-X-From: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Tue Apr 25 15:22:03 2017 Return-path: Envelope-to: glka-linux-api@m.gmane.org Original-Received: from vger.kernel.org ([209.132.180.67]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1d30Pq-00052D-BO for glka-linux-api@m.gmane.org; Tue, 25 Apr 2017 15:22:02 +0200 Original-Received: (majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org) by vger.kernel.org via listexpand id S1176079AbdDYNWI (ORCPT ); Tue, 25 Apr 2017 09:22:08 -0400 Original-Received: from mx1.redhat.com ([209.132.183.28]:45302 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1430823AbdDYNWH (ORCPT ); Tue, 25 Apr 2017 09:22:07 -0400 Original-Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 65AEC8E66A; Tue, 25 Apr 2017 13:22:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 65AEC8E66A Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=fweimer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 65AEC8E66A Original-Received: from oldenburg.str.redhat.com (ovpn-116-195.ams2.redhat.com [10.36.116.195]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C1BB984D97; Tue, 25 Apr 2017 13:22:01 +0000 (UTC) In-Reply-To: <20170309001435.GJ2082-4P1ElwuDYu6sTnJN9+BGXg@public.gmane.org> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 25 Apr 2017 13:22:06 +0000 (UTC) Original-Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Precedence: bulk List-ID: X-Mailing-List: linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Xref: news.gmane.org gmane.linux.kernel.api:23092 gmane.linux.kernel:2463411 gmane.linux.lib.musl.general:11292 Archived-At: On 03/09/2017 01:14 AM, Szabolcs Nagy wrote: > the other way (linux header included first) is > problematic because linux headers don't follow > all the standards the libc follows, they violate > namespace rules in their struct definitions, so > the libc definitions are necessarily incompatible > with them and thus different translation units can > end up refering to the same object through > incompatible types which is undefined. > (even if the abi matches and thus works across > the syscall interface, a sufficiently smart > toolchain can break such code at link time, > and since the libc itself uses its own definitons > that's what user code should use too). I don't think this is relevant in this context. LTO implementations have to deal with this already. For glibc's sake alone, it must be supported to link together code using differing feature test macros. Thanks, Florian