[PATCH v2] kbuild: remove sed command from cmd_ar_builtin

[Masahiro Yamada <masahiroy@kernel.org>]

Replace a pipeline of echo and sed with printf to decrease process forks.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

Changes in v2:
  - Avoid the pipeline if there is no object to put in the archive

 scripts/Makefile.build | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index cac070aee791..784f46d41959 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -358,9 +358,8 @@ $(subdir-modorder): $(obj)/%/modules.order: $(obj)/% ;
 
 quiet_cmd_ar_builtin = AR      $@
       cmd_ar_builtin = rm -f $@; \
-		echo $(patsubst $(obj)/%,%,$(real-prereqs)) | \
-		sed -E 's:([^ ]+):$(obj)/\1:g' | \
-		xargs $(AR) cDPrST $@
+	$(if $(real-prereqs), printf "$(obj)/%s " $(patsubst $(obj)/%,%,$(real-prereqs)) | xargs) \
+	$(AR) cDPrST $@
 
 $(obj)/built-in.a: $(real-obj-y) FORCE
 	$(call if_changed,ar_builtin)
-- 
2.32.0