From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031656AbeCAOvg (ORCPT ); Thu, 1 Mar 2018 09:51:36 -0500 Received: from conssluserg-04.nifty.com ([210.131.2.83]:30692 "EHLO conssluserg-04.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031642AbeCAOve (ORCPT ); Thu, 1 Mar 2018 09:51:34 -0500 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-04.nifty.com w21EpBne010651 X-Nifty-SrcIP: [209.85.213.47] X-Google-Smtp-Source: AG47ELsQv1ZuP+3XjfRjlr6988tQuJu1ErxrRhhVDmbun8ZvwU1GZJiTMlySAG9on4fAS6rhvI51MP0WdMD2bAZGmNE= MIME-Version: 1.0 In-Reply-To: References: <1519776926-30459-1-git-send-email-yamada.masahiro@socionext.com> <1519776926-30459-6-git-send-email-yamada.masahiro@socionext.com> <20180228051525.a2vouqs6djnd2cnf@huvuddator> <20180301111801.gdhoam4kqrbqnasv@huvuddator> From: Masahiro Yamada Date: Thu, 1 Mar 2018 23:50:30 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] kconfig: remove redundant streamline_config.pl prerequisite To: Ulf Magnusson Cc: Linux Kbuild mailing list , Marc Herbert , Sam Ravnborg , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2018-03-01 23:44 GMT+09:00 Masahiro Yamada : > 2018-03-01 23:39 GMT+09:00 Masahiro Yamada : >> 2018-03-01 20:18 GMT+09:00 Ulf Magnusson : >>> The local{yes,mod}config targets currently have streamline_config.pl as >>> a prerequisite. This is redundant, because streamline_config.pl is a >>> checked-in file with no prerequisites. >>> >>> Remove the prerequisite and reference streamline_config.pl directly in >>> the recipe of the rule instead. >>> >>> Signed-off-by: Ulf Magnusson >>> --- >>> scripts/kconfig/Makefile | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile >>> index 1f74336d4e23..58be52cb464d 100644 >> >> >> Thanks! Almost good. >> >> Just small nits. >> >> >>> --- a/scripts/kconfig/Makefile >>> +++ b/scripts/kconfig/Makefile >>> @@ -77,9 +77,9 @@ silentoldconfig: $(obj)/conf >>> touch include/generated/autoksyms.h >>> $< $(silent) --$@ $(Kconfig) >>> >>> -localyesconfig localmodconfig: $(obj)/streamline_config.pl $(obj)/conf >>> +localyesconfig localmodconfig: $(obj)/conf >>> $(Q)mkdir -p include/config include/generated >>> - $(Q)perl $< --$@ $(srctree) $(Kconfig) > .tmp.config >>> + $(Q)perl $(obj)/streamline_config.pl --$@ $(srctree) $(Kconfig) > .tmp.config >> >> >> >> '$(src)/streamline_config.pl' is better than '$(obj)/streamline_config.pl' >> since it is a checked-in file. >> >> '$(src)' and '$(obj)' are always the same. >> (https://github.com/torvalds/linux/blob/master/scripts/Makefile.build#L6) >> >> >> So, there is no effective difference. >> It is just a coding convention to use $(obj)/ for generated files, >> and $(src)/ for source files. >> >> The original code already used $(obj)/, so this is not your fault >> but I want to fix it while we are here. > > > No. > > This is not a matter of taste, > but a bug that must be fixed. > > > This patch breaks out-of-tree build. > > If O=... is given, it is error. > > > $ make O=foo localyesconfig > make[1]: Leaving directory '/home/masahiro/workspace/linux-yamada/foo' > masahiro@grover:~/workspace/linux-yamada$ make O=foo localyesconfig > make[1]: Entering directory '/home/masahiro/workspace/linux-yamada/foo' > GEN ./Makefile > Can't open perl script "scripts/kconfig/streamline_config.pl": No such > file or directory > ../scripts/kconfig/Makefile:46: recipe for target 'localyesconfig' failed > make[2]: *** [localyesconfig] Error 2 > /home/masahiro/workspace/linux-yamada/Makefile:521: recipe for target > 'localyesconfig' failed > make[1]: *** [localyesconfig] Error 2 > make[1]: Leaving directory '/home/masahiro/workspace/linux-yamada/foo' > Makefile:146: recipe for target 'sub-make' failed > make: *** [sub-make] Error 2 > > > > The right fix is $(srctree)/$(src)/streamline_config.pl > > For somebody wondering why the current code works for out-of-tree building. Kbuild sets VPATH (https://github.com/torvalds/linux/blob/master/Makefile#L208) So, Make searches for pre-requisites in both objtree and srctree when building out-of-tree. VPATH does not work for recipe lines. So, we need to specify the exact path to streamline_config.pl -- Best Regards Masahiro Yamada