[PATCH 1/2] kbuild: remove top-level built-in.a

From: Masahiro Yamada
Date: Sun Jan 13 2019 - 22:28:52 EST


The symbol table in the final archive is unneeded because it is passed
to the linker after the --whole-archive option. Every object file in
the archive is included in the link anyway.

Pass thin archives from subdirectories directly to the linker, and
remove the final archiving step.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

scripts/link-vmlinux.sh | 30 ++++++------------------------
1 file changed, 6 insertions(+), 24 deletions(-)

diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index c8cf453..4788def 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -44,24 +44,6 @@ info()
fi
}

-# Thin archive build here makes a final archive with symbol table and indexes
-# from vmlinux objects INIT and MAIN, which can be used as input to linker.
-# KBUILD_VMLINUX_LIBS archives should already have symbol table and indexes
-# added.
-#
-# Traditional incremental style of link does not require this step
-#
-# built-in.a output file
-#
-archive_builtin()
-{
- info AR built-in.a
- rm -f built-in.a;
- ${AR} rcsTP${KBUILD_ARFLAGS} built-in.a \
- ${KBUILD_VMLINUX_INIT} \
- ${KBUILD_VMLINUX_MAIN}
-}
-
# Link of vmlinux.o used for section mismatch analysis
# ${1} output file
modpost_link()
@@ -69,7 +51,8 @@ modpost_link()
local objects

objects="--whole-archive \
- built-in.a \
+ ${KBUILD_VMLINUX_INIT} \
+ ${KBUILD_VMLINUX_MAIN} \
--no-whole-archive \
--start-group \
${KBUILD_VMLINUX_LIBS} \
@@ -88,7 +71,8 @@ vmlinux_link()

if [ "${SRCARCH}" != "um" ]; then
objects="--whole-archive \
- built-in.a \
+ ${KBUILD_VMLINUX_INIT} \
+ ${KBUILD_VMLINUX_MAIN} \
--no-whole-archive \
--start-group \
${KBUILD_VMLINUX_LIBS} \
@@ -99,7 +83,8 @@ vmlinux_link()
-T ${lds} ${objects}
else
objects="-Wl,--whole-archive \
- built-in.a \
+ ${KBUILD_VMLINUX_INIT} \
+ ${KBUILD_VMLINUX_MAIN} \
-Wl,--no-whole-archive \
-Wl,--start-group \
${KBUILD_VMLINUX_LIBS} \
@@ -160,7 +145,6 @@ cleanup()
rm -f .tmp_System.map
rm -f .tmp_kallsyms*
rm -f .tmp_vmlinux*
- rm -f built-in.a
rm -f System.map
rm -f vmlinux
rm -f vmlinux.o
@@ -217,8 +201,6 @@ fi;
# final build of init/
${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init

-archive_builtin
-
#link vmlinux.o
info LD vmlinux.o
modpost_link vmlinux.o
--
2.7.4