kbuild: save $(strip ...) for calling if_changed and friends (c2341e2a) · Commits · 戴 / test

The string returned by $(filter-out ...) does not contain any leading or trailing spaces. With the previous commit, 'any-prereq' no longer contains any excessive spaces. Nor does 'cmd-check' since it expands to a $(filter-out ...) call. So, only the space that matters is the one between 'any-prereq' and 'cmd-check'. By removing it from the code, we can save $(strip ...) evaluation. This refactoring is possible because $(any-prereq)$(cmd-check) is only passed to the first argument of $(if ...), so we are only interested in whether or not it is empty. Signed-off-by:

Masahiro Yamada <yamada.masahiro@socionext.com>

scripts/Kbuild.include

+3 −3

Original line number	Diff line number	Diff line
		@@ -228,12 +228,12 @@ make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))
		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)), \
		if_changed = $(if $(any-prereq)$(cmd-check), \
		$(cmd); \
		printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)

		# Execute the command and also postprocess generated .d dependencies file.
		if_changed_dep = $(if $(strip $(any-prereq) $(cmd-check)),$(cmd_and_fixdep),@:)
		if_changed_dep = $(if $(any-prereq)$(cmd-check),$(cmd_and_fixdep),@:)

		cmd_and_fixdep = \
		$(cmd); \
		@@ -243,7 +243,7 @@ cmd_and_fixdep = \
		# Usage: $(call if_changed_rule,foo)
		# Will check if $(cmd_foo) or any of the prerequisites changed,
		# and if so will execute $(rule_foo).
		if_changed_rule = $(if $(strip $(any-prereq) $(cmd-check)),$(rule_$(1)),@:)
		if_changed_rule = $(if $(any-prereq)$(cmd-check),$(rule_$(1)),@:)

		###
		# why - tell why a target got built

Admin message