From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([59.151.112.132]:37754 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1750749AbdFNHGS (ORCPT ); Wed, 14 Jun 2017 03:06:18 -0400 Subject: Re: [PATCH v2] Kbuild: tiny correction on `make help` References: <1496740073-3320-1-git-send-email-caoj.fnst@cn.fujitsu.com> <593FB5F2.4040206@cn.fujitsu.com> From: Cao jin Message-ID: <5940E10A.10309@cn.fujitsu.com> Date: Wed, 14 Jun 2017 15:08:58 +0800 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Masahiro Yamada Cc: Linux Kernel Mailing List , Linux Kbuild mailing list , Michal Marek On 06/14/2017 09:15 AM, Masahiro Yamada wrote: > 2017-06-13 18:52 GMT+09:00 Cao jin : >> Yamada-san, >> >> I have a question on the current top level Makefile. There are >> following lines, I have trouble to understand "firstword x$(MAKEFLAGS)" >> in 2nd line, why there is a 'x' there? >> >> >> ifneq ($(filter 4.%,$(MAKE_VERSION)),) # make-4 >> ifneq ($(filter %s ,$(firstword x$(MAKEFLAGS))),) > > > I do not understand the 'x' either. > > Michal suggested the code according to the following: > https://patchwork.kernel.org/patch/3291301/ > (I hope Michal can help you.) > It does helps. > > My first guess was, it was added just in case $(MAKEFLAGS) is empty. > Actually $(firstword ) seems to work with empty argument, though. > I see, I guess you are saying it was added in case there is no single-letter flags in $(MAKEFLAGS) while it has "--debug=jobs", that make sense to me. Thanks very much, Yamada-san. -- Sincerely, Cao jin