From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DEDCEC7618F for ; Wed, 17 Jul 2019 16:46:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B988621743 for ; Wed, 17 Jul 2019 16:46:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728744AbfGQQqx (ORCPT ); Wed, 17 Jul 2019 12:46:53 -0400 Received: from gate.crashing.org ([63.228.1.57]:57045 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728430AbfGQQqx (ORCPT ); Wed, 17 Jul 2019 12:46:53 -0400 Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id x6HGkUed008627; Wed, 17 Jul 2019 11:46:30 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id x6HGkSxG008626; Wed, 17 Jul 2019 11:46:28 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Wed, 17 Jul 2019 11:46:28 -0500 From: Segher Boessenkool To: Masahiro Yamada Cc: Michael Ellerman , Stephen Rothwell , Linux Kernel Mailing List , Nicholas Piggin , Paul Mackerras , linuxppc-dev Subject: Re: [PATCH] powerpc: remove meaningless KBUILD_ARFLAGS addition Message-ID: <20190717164628.GN20882@gate.crashing.org> References: <20190713032106.8509-1-yamada.masahiro@socionext.com> <20190713124744.GS14074@gate.crashing.org> <20190713131642.GU14074@gate.crashing.org> <20190713235430.GZ14074@gate.crashing.org> <87v9w393r5.fsf@concordia.ellerman.id.au> <20190715072959.GB20882@gate.crashing.org> <87pnma89ak.fsf@concordia.ellerman.id.au> <20190717143811.GL20882@gate.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 18, 2019 at 12:19:36AM +0900, Masahiro Yamada wrote: > On Wed, Jul 17, 2019 at 11:38 PM Segher Boessenkool > wrote: > > > > On Tue, Jul 16, 2019 at 10:15:47PM +1000, Michael Ellerman wrote: > > > Segher Boessenkool writes: > > > And it's definitely calling ar with no flags, eg: > > > > > > rm -f init/built-in.a; powerpc-linux-ar rcSTPD init/built-in.a init/main.o init/version.o init/do_mounts.o init/do_mounts_rd.o init/do_mounts_initrd.o init/do_mounts_md.o init/initramfs.o init/init_task.o > > > > This uses thin archives. Those will work fine. > > > > The failing case was empty files IIRC, stuff created from no inputs. > > Actually, empty files are created everywhere. > cmd_ar_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) $@ > $(real-prereqs) You use thin archives. Does every config use thin archives always nowadays? > BTW, your commit 8995ac8702737147115e1c75879a1a2d75627b9e > dates back to 2008. > > At that time, thin archive was not used. Yes, I know. This isn't about built-in.[oa], it is about *other* archives we at least *used to* create. If we *know* we do not anymore, then this workaround can of course be removed (and good riddance). If ar creates an archive file (a real one, not a thin archive), and it has no input files, it uses its default object format as destination format, if it isn't told to use something else. And that doesn't work, it needs to use some format compatible with what that archive later is linked with. Segher