From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Herbert J. Skuhra" Newsgroups: gmane.emacs.devel Subject: Re: USE_LSB_TAG not supported on this platform Date: Tue, 09 Feb 2016 12:12:02 +0100 Message-ID: <8660xy3zp9.wl-herbert@mailbox.org> References: <86powcjei0.wl-herbert@mailbox.org> <56B3F962.8010203@cs.ucla.edu> <86mvrejegc.wl-herbert@mailbox.org> <86si15ygd9.wl-herbert@mailbox.org> <85twlksgds.fsf@iznogoud.viz> <8660y0nqze.wl-herbert@mailbox.org> <56B8F03C.3010709@cs.ucla.edu> <867fie4xj6.wl-herbert@mailbox.org> <56B93C71.6060602@cs.ucla.edu> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-Trace: ger.gmane.org 1455016347 25276 80.91.229.3 (9 Feb 2016 11:12:27 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 9 Feb 2016 11:12:27 +0000 (UTC) Cc: emacs-devel@gnu.org To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Feb 09 12:12:17 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1aT6DR-0005r0-Er for ged-emacs-devel@m.gmane.org; Tue, 09 Feb 2016 12:12:17 +0100 Original-Received: from localhost ([::1]:54385 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aT6DQ-0001NV-0S for ged-emacs-devel@m.gmane.org; Tue, 09 Feb 2016 06:12:16 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55038) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aT6DL-0001ND-Vw for emacs-devel@gnu.org; Tue, 09 Feb 2016 06:12:12 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aT6DG-0004gd-Pn for emacs-devel@gnu.org; Tue, 09 Feb 2016 06:12:11 -0500 Original-Received: from mx2.mailbox.org ([80.241.60.215]:49534) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aT6DG-0004gW-Fc for emacs-devel@gnu.org; Tue, 09 Feb 2016 06:12:06 -0500 Original-Received: from smtp1.mailbox.org (smtp1.mailbox.org [80.241.60.240]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx2.mailbox.org (Postfix) with ESMTPS id B4767434A2; Tue, 9 Feb 2016 12:12:05 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mailbox.org; h= content-type:content-type:mime-version:user-agent:references :in-reply-to:subject:subject:from:from:message-id:date:date :received; s=mail20150812; t=1455016323; bh=SS2zEDfQ5BekTUCARFMt 6JJ8aXaDb9QT86Ucr6Lso2s=; b=xCY9o/PFFItXLcAoPg2V5ILye6JF1bBRpQvA 9cWuMsnwr1FdhM3GlQwIOa2OhBcR4U+FTk87QOyVxbTg1vhXK8m0CKWq3jLp2nRJ X9QsCKYMuBZKM0wl22KpdriHmTXZl55zogj+WtozlAiEozvjZO6shTDBChRsjG6P dnu15BB8MSserFXBp+6esrsEnf0OcrAE9rzAOsl0XPwMHCbHV+Y5tP/RG+c/Ash/ 9xa4j6KuwViNewcMbxVXJICszyT29MxJPzchpT/+1u98VbUCkkaxyX763EhD6O20 OEnc241KvyUcFrBIv7IwnuWZjnim5Pn5DxVh4LWhorOzEd+yxA== X-Virus-Scanned: amavisd-new at heinlein-support.de Original-Received: from smtp1.mailbox.org ([80.241.60.240]) by gerste.heinlein-support.de (gerste.heinlein-support.de [91.198.250.173]) (amavisd-new, port 10030) with ESMTP id AeevRglHBV1q; Tue, 9 Feb 2016 12:12:03 +0100 (CET) In-Reply-To: <56B93C71.6060602@cs.ucla.edu> User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/25.1 Mule/6.0 (HANACHIRUSATO) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 80.241.60.215 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:199587 Archived-At: On Tue, 09 Feb 2016 02:10:09 +0100, Paul Eggert wrote: > > On 02/08/2016 03:01 PM, Herbert J. Skuhra wrote: > > GCC 5 works but clang still fails. If I add > > > > #define alignas _Alignas > > > > to src/lisp.h the build succeeds. > > Thanks, could you explain why that "#define" is helpful? On my > platform (Fedora 23 x86-64, clang 3.7.0) clang's , which > is in /usr/lib/clang/3.7.0/include/stdalign.h, contains this: > > #ifndef __cplusplus > #define alignas _Alignas > #define alignof _Alignof > #endif > > and src/lisp.h includes before using or checking alignas, > so there should be no need to add "#define alignas _Alignas" to > lisp.h. Checking for working stdalign.h fails with clang: configure:28312: clang -c -g3 -O2 conftest.c >&5 conftest.c:309:30: error: 'test_double' declared as an array with a negative size char test_double[ao (double) % _Alignof (double) == 0 ? 1 : -1]; ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ conftest.c:307:31: note: expanded from macro 'ao' # define ao(type) offsetof (struct { char a; type b; }, b) ^ /usr/include/stddef.h:65:32: note: expanded from macro 'offsetof' #define offsetof(type, member) __offsetof(type, member) ^ /usr/include/sys/cdefs.h:476:34: note: expanded from macro '__offsetof' #define __offsetof(type, field) __builtin_offsetof(type, field) ^ 1 error generated. If I modify the configure script as follows --- configure.bak 2016-02-09 12:47:41.800783000 +0100 +++ configure 2016-02-09 12:48:06.230442000 +0100 @@ -28113,7 +28113,7 @@ if ac_fn_c_try_compile "$LINENO"; then : gl_cv_header_working_stdalign_h=yes else - gl_cv_header_working_stdalign_h=no + gl_cv_header_working_stdalign_h=yes fi rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext fi the build succeeds. > Is there a file src/stdalign.h in your build directory? Yes, lib/stdalign.h. (Not after modifying configure.) > If so, why is it there, and why does it not define alignas? Sorry, I couldn't figure it out yet. > Are you building with clang++? No. -- Herbert