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=-17.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=unavailable 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 D749AC07E9B for ; Fri, 9 Jul 2021 08:25:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BCF66613CC for ; Fri, 9 Jul 2021 08:25:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231550AbhGII2B (ORCPT ); Fri, 9 Jul 2021 04:28:01 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:51002 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S229685AbhGII2A (ORCPT ); Fri, 9 Jul 2021 04:28:00 -0400 X-UUID: e2fa50fcf82b4f31a3406b086a65e148-20210709 X-UUID: e2fa50fcf82b4f31a3406b086a65e148-20210709 Received: from mtkcas10.mediatek.inc [(172.21.101.39)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 54868000; Fri, 09 Jul 2021 16:25:13 +0800 Received: from mtkcas10.mediatek.inc (172.21.101.39) by mtkmbs05n1.mediatek.inc (172.21.101.15) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 9 Jul 2021 16:25:12 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas10.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Fri, 9 Jul 2021 16:25:12 +0800 From: Lecopzer Chen To: CC: , , , , , , , , , Subject: Re: [PATCH v3 1/2] Kbuild: lto: add CONFIG_MAKE_VERSION Date: Fri, 9 Jul 2021 16:25:12 +0800 Message-ID: <20210709082512.25208-1-lecopzer.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Tue, Jul 6, 2021 at 2:06 AM Lecopzer Chen wrote: > > > > > On Sun, Jul 4, 2021 at 7:03 PM Masahiro Yamada wrote: > > > > > > > > On Fri, Jul 2, 2021 at 12:29 PM Lecopzer Chen > > > > wrote: > > > > > > > > > > To check the GNU make version. Used by the LTO Kconfig. > > > > > > > > > > LTO with MODVERSIONS will fail in generating correct CRC because > > > > > the makefile rule doesn't work for make with version 3.8X.[1] > > > > > > > > > > Thus we need to check make version during selecting on LTO Kconfig. > > > > > Add CONFIG_MAKE_VERSION which means MAKE_VERSION in canonical digits > > > > > for arithmetic comparisons. > > > > > > > > > > [1] https://lore.kernel.org/lkml/20210616080252.32046-1-lecopzer.chen@mediatek.com/ > > > > > Signed-off-by: Lecopzer Chen > > > > > --- > > > > > > > > > > > > NACK. > > > > > > > > "Let's add MAKE_VERSION >= 40200 restriction > > > > just because I cannot write correct code that > > > > works for older Make" is a horrible idea. > > > > > > > > Also, Kconfig is supposed to check the compiler > > > > (or toolchains) capability, not host tool versions. > > > > > > I feel like requiring a Make that's half a decade old for a feature > > > that also requires a toolchain released last October ago isn't > > > entirely unreasonable. > > > > > > That being said, if Masahiro prefers not to rely on the wildcard > > > function's behavior here, which is a reasonable request, we could > > > simply use the shell to test for the file's existence: > > > > > > diff --git a/scripts/Makefile.build b/scripts/Makefile.build > > > index 34d257653fb4..c6bd62f518ff 100644 > > > --- a/scripts/Makefile.build > > > +++ b/scripts/Makefile.build > > > @@ -388,7 +388,7 @@ ifeq ($(CONFIG_LTO_CLANG) $(CONFIG_MODVERSIONS),y y) > > > cmd_update_lto_symversions = \ > > > rm -f $@.symversions \ > > > $(foreach n, $(filter-out FORCE,$^), \ > > > - $(if $(wildcard $(n).symversions), \ > > > + $(if $(shell test -s $(n).symversions && echo y), \ > > > ; cat $(n).symversions >> $@.symversions)) > > > else > > > cmd_update_lto_symversions = echo >/dev/null > > > > > > This is not quite as efficient as using wildcard, but should work with > > > older Make versions too. Thoughts? > > > > > > > > > I've tested this in both make-4.3 and 3.81, and the CRC is correct. > > But I'm not sure if anyone would have the "arg list too long" issue. > > > > Tested-by: Lecopzer Chen > > Thank you for testing. This should produce a command identical to the > wildcard version (with newer Make versions), so that shouldn't be an > issue. If nobody objects to this approach, would you mind putting this > into a proper patch and sending it as v4? Sure, I'll rebase the whole commit and send as v4 soon.