The string returned by $(filter-out ...) does not contain any leading
or trailing spaces.
So, only the space that matters is the one between
$(filter-out $(PHONY),$?)
and
$(filter-out $(PHONY) $(wildcard $^),$^)
By removing it from the code, we can save $(strip ...) evaluation.
This refactoring is possible because $(any-prereq) is only passed to
the first argument of $(if ...), so we are only interested in whether
it is empty or not.
This is also the prerequisite for the next commit.
Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---
scripts/Kbuild.include | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 4bec04c89750..0fa93f6de0b0 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -231,7 +231,7 @@ make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))
# Find any prerequisites that is newer than target or that does not exist.
# PHONY targets skipped in both cases.
-any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
+any-prereq = $(filter-out $(PHONY),$?)$(filter-out $(PHONY) $(wildcard $^),$^)
# Execute command if command has changed or prerequisite(s) are updated.
if_changed = $(if $(strip $(any-prereq) $(cmd-check)), \
@@ -274,7 +274,7 @@ ifeq ($(KBUILD_VERBOSE),2)
why = \
$(if $(filter $@, $(PHONY)),- due to target is PHONY, \
$(if $(wildcard $@), \
- $(if $(strip $(any-prereq)),- due to: $(any-prereq), \
+ $(if $(any-prereq),- due to: $(any-prereq), \
$(if $(cmd-check), \
$(if $(cmd_$@),- due to command line change, \
$(if $(filter $@, $(targets)), \
--
2.17.1
