From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from conuserg-12.nifty.com ([210.131.2.79]:28701 "EHLO conuserg-12.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727307AbgAFDXx (ORCPT ); Sun, 5 Jan 2020 22:23:53 -0500 From: Masahiro Yamada Subject: [PATCH] kbuild: allow modules to link *.a archives Date: Mon, 6 Jan 2020 12:23:24 +0900 Message-Id: <20200106032324.3147-1-masahiroy@kernel.org> Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: linux-kbuild@vger.kernel.org Cc: Fumiya Shigemitsu , Yongxin Liu , Masahiro Yamada , Michal Marek , linux-kernel@vger.kernel.org Since commit 69ea912fda74 ("kbuild: remove unneeded link_multi_deps"), modules cannot link *.a archives. I do not see such a usecase in the upstream code, but multiple people reported this issue, so it seems to be a desired feature for external modules. For example, libfoo.a is not linked in the following test case: obj-m := foo.o foo-objs := foo1.o libfoo.a Instead of reverting the offending commit, I wrote slightly cleaner code. I added multi-m-prereqs to avoid code duplication. Reported-by: Fumiya Shigemitsu Reported-by: Yongxin Liu Signed-off-by: Masahiro Yamada --- scripts/Makefile.build | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index b734ac8a654e..a8481b765ea8 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -265,8 +265,10 @@ $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE $(call cmd,force_checksrc) $(call if_changed_rule,cc_o_c) +multi-m-prereqs = $(addprefix $(obj)/, $($*-objs) $($*-y) $($*-m)) + cmd_mod = { \ - echo $(if $($*-objs)$($*-y)$($*-m), $(addprefix $(obj)/, $($*-objs) $($*-y) $($*-m)), $(@:.mod=.o)); \ + echo $(if $(multi-m-prereqs), $(multi-m-prereqs), $(@:.mod=.o)); \ $(cmd_undef_syms); \ } > $@ @@ -427,13 +429,13 @@ targets += $(obj)/lib-ksyms.o endif # NOTE: -# Do not replace $(filter %.o,^) with $(real-prereqs). When a single object +# Do not replace $(multi-m-prereqs) with $(real-prereqs). When a single object # module is turned into a multi object module, $^ will contain header file # dependencies recorded in the .*.cmd file. quiet_cmd_link_multi-m = LD [M] $@ - cmd_link_multi-m = $(LD) $(ld_flags) -r -o $@ $(filter %.o,$^) + cmd_link_multi-m = $(LD) $(ld_flags) -r -o $@ $(multi-m-prereqs) -$(multi-used-m): FORCE +$(multi-used-m): $(obj)/%.o: FORCE $(call if_changed,link_multi-m) $(call multi_depend, $(multi-used-m), .o, -objs -y -m) -- 2.17.1