From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from conuserg-10.nifty.com ([210.131.2.77]:59020 "EHLO conuserg-10.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726498AbgAFHYk (ORCPT ); Mon, 6 Jan 2020 02:24:40 -0500 From: Masahiro Yamada Subject: [PATCH v2 2/2] kbuild: allow modules to link *.a archives Date: Mon, 6 Jan 2020 16:23:55 +0900 Message-Id: <20200106072355.32178-2-masahiroy@kernel.org> In-Reply-To: <20200106072355.32178-1-masahiroy@kernel.org> References: <20200106072355.32178-1-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 I used $(filter $(multi-m-prereqs), $^) to avoid linking the same object multiple times in case Makefile is written as follows: obj-m := foo.o foo-$(CONFIG_FOO1_X) += foo1.o foo-$(CONFIG_FOO1_Y) += foo1.o foo-y += libfoo.a Reported-by: Fumiya Shigemitsu Reported-by: Yongxin Liu Signed-off-by: Masahiro Yamada --- Changes in v2: - add $(filter ..., $^) to avoid build errors caused by multiple linking scripts/Makefile.build | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d8445b696d5b..9ffb9300705e 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -429,13 +429,13 @@ targets += $(obj)/lib-ksyms.o endif # NOTE: -# Do not replace $(filter %.o,^) 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. +# Do not replace $(filter $(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 $@ $(filter $(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