scripts/Kbuild.include - codeaurora/cp-linux - Gitiles

 ####
 # kbuild: Generic definitions

 # Convenient variables
 comma   := ,
 quote   := "
 squote  := '
 empty   :=
 space   := $(empty) $(empty)
 pound   := \#

 ###
 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
 dot-target = $(dir $@).$(notdir $@)

 ###
 # The temporary file to save gcc -MD generated dependencies must not
 # contain a comma
 depfile = $(subst $(comma),_,$(dot-target).d)

 ###
 # filename of target with directory and extension stripped
 basetarget = $(basename $(notdir $@))

 ###
 # filename of first prerequisite with directory and extension stripped
 baseprereq = $(basename $(notdir $<))

 ###
 # Escape single quote for use in echo statements
 escsq = $(subst $(squote),'\$(squote)',$1)

 ###
 # Easy method for doing a status message
        kecho := :
  quiet_kecho := echo
 silent_kecho := :
 kecho := $($(quiet)kecho)

 ###
 # filechk is used to check if the content of a generated file is updated.
 # Sample usage:
 # define filechk_sample
 #	echo $KERNELRELEASE
 # endef
 # version.h : Makefile
 #	$(call filechk,sample)
 # The rule defined shall write to stdout the content of the new file.
 # The existing file will be compared with the new one.
 # - If no file exist it is created
 # - If the content differ the new file is used
 # - If they are equal no change, and no timestamp update
 # - stdin is piped in from the first prerequisite ($<) so one has
 #   to specify a valid file as first prerequisite (often the kbuild file)
 define filechk
 	$(Q)set -e;				\
 	$(kecho) '  CHK     $@';		\
 	mkdir -p $(dir $@);			\
 	$(filechk_$(1)) < $< > $@.tmp;		\
 	if [ -r $@ ] && cmp -s $@ $@.tmp; then	\
 		rm -f $@.tmp;			\
 	else					\
 		$(kecho) '  UPD     $@';	\
 		mv -f $@.tmp $@;		\
 	fi
 endef

 ######
 # gcc support functions
 # See documentation in Documentation/kbuild/makefiles.txt

 # cc-cross-prefix
 # Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
 # Return first prefix where a prefix$(CC) is found in PATH.
 # If no $(CC) found in PATH with listed prefixes return nothing
 cc-cross-prefix =  \
 	$(word 1, $(foreach c,$(1),                                   \
 		$(shell set -e;                                       \
 		if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \
 			echo $(c);                                    \
 		fi)))

 # output directory for tests below
 TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)

 # try-run
 # Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
 # Exit code chooses option. "$$TMP" is can be used as temporary file and
 # is automatically cleaned up.
 try-run = $(shell set -e;		\
 	TMP="$(TMPOUT).$$$$.tmp";	\
 	TMPO="$(TMPOUT).$$$$.o";	\
 	if ($(1)) >/dev/null 2>&1;	\
 	then echo "$(2)";		\
 	else echo "$(3)";		\
 	fi;				\
 	rm -f "$$TMP" "$$TMPO")

 # as-option
 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)

 as-option = $(call try-run,\
 	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))

 # as-instr
 # Usage: cflags-y += $(call as-instr,instr,option1,option2)

 as-instr = $(call try-run,\
 	printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))

 # cc-option
 # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)

 cc-option = $(call try-run,\
 	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))

 # cc-option-yn
 # Usage: flag := $(call cc-option-yn,-march=winchip-c6)
 cc-option-yn = $(call try-run,\
 	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)

 # cc-option-align
 # Prefix align with either -falign or -malign
 cc-option-align = $(subst -functions=0,,\
 	$(call cc-option,-falign-functions=0,-malign-functions=0))

 # cc-disable-warning
 # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
 cc-disable-warning = $(call try-run,\
 	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))

 # cc-name
 # Expands to either gcc or clang
 cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)

 # cc-version
 cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))

 # cc-fullversion
 cc-fullversion = $(shell $(CONFIG_SHELL) \
 	$(srctree)/scripts/gcc-version.sh -p $(CC))

 # cc-ifversion
 # Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
 cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))

 # cc-ldoption
 # Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
 cc-ldoption = $(call try-run,\
 	$(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))

 # ld-option
 # Usage: LDFLAGS += $(call ld-option, -X)
 ld-option = $(call try-run,\
 	$(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))

 # ar-option
 # Usage: KBUILD_ARFLAGS := $(call ar-option,D)
 # Important: no spaces around options
 ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))

 # ld-version
 # Note this is mainly for HJ Lu's 3 number binutil versions
 ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)

 # ld-ifversion
 # Usage:  $(call ld-ifversion, -ge, 22252, y)
 ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))

 ######

 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
 # Usage:
 # $(Q)$(MAKE) $(build)=dir
 build := -f $(srctree)/scripts/Makefile.build obj

 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
 # Usage:
 # $(Q)$(MAKE) $(modbuiltin)=dir
 modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj

 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
 # Usage:
 # $(Q)$(MAKE) $(dtbinst)=dir
 dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj

 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
 # Usage:
 # $(Q)$(MAKE) $(clean)=dir
 clean := -f $(srctree)/scripts/Makefile.clean obj

 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
 # Usage:
 # $(Q)$(MAKE) $(hdr-inst)=dir
 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj

 # Prefix -I with $(srctree) if it is not an absolute path.
 # skip if -I has no parameter
 addtree = $(if $(patsubst -I%,%,$(1)), \
 $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1))

 # Find all -I options and call addtree
 flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))

 # echo command.
 # Short version is used, if $(quiet) equals `quiet_', otherwise full one.
 echo-cmd = $(if $($(quiet)cmd_$(1)),\
 	echo '  $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)

 # printing commands
 cmd = @$(echo-cmd) $(cmd_$(1))

 # Add $(obj)/ for paths that are not absolute
 objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))

 ###
 # if_changed      - execute command if any prerequisite is newer than
 #                   target, or command line has changed
 # if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
 #                   including used config symbols
 # if_changed_rule - as if_changed but execute rule instead
 # See Documentation/kbuild/makefiles.txt for more info

 ifneq ($(KBUILD_NOCMDDEP),1)
 # Check if both arguments has same arguments. Result is empty string if equal.
 # User may override this check using make KBUILD_NOCMDDEP=1
 arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
                     $(filter-out $(cmd_$@),   $(cmd_$(1))) )
 else
 arg-check = $(if $(strip $(cmd_$@)),,1)
 endif

 # Replace >$< with >$$< to preserve $ when reloading the .cmd file
 # (needed for make)
 # Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
 # (needed for make)
 # Replace >'< with >'\''< to be able to enclose the whole string in '...'
 # (needed for the shell)
 make-cmd = $(call escsq,$(subst $(pound),$$(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 $^),$^)

 # Execute command if command has changed or prerequisite(s) are updated.
 #
 if_changed = $(if $(strip $(any-prereq) $(arg-check)),                       \
 	@set -e;                                                             \
 	$(echo-cmd) $(cmd_$(1));                                             \
 	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) $(arg-check) ),                  \
 	@set -e;                                                             \
 	$(echo-cmd) $(cmd_$(1));                                             \
 	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
 	rm -f $(depfile);                                                    \
 	mv -f $(dot-target).tmp $(dot-target).cmd)

 # 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) $(arg-check) ),                 \
 	@set -e;                                                             \
 	$(rule_$(1)))

 ###
 # why - tell why a a target got build
 #       enabled by make V=2
 #       Output (listed in the order they are checked):
 #          (1) - due to target is PHONY
 #          (2) - due to target missing
 #          (3) - due to: file1.h file2.h
 #          (4) - due to command line change
 #          (5) - due to missing .cmd file
 #          (6) - due to target not in $(targets)
 # (1) PHONY targets are always build
 # (2) No target, so we better build it
 # (3) Prerequisite is newer than target
 # (4) The command line stored in the file named dir/.target.cmd
 #     differed from actual command line. This happens when compiler
 #     options changes
 # (5) No dir/.target.cmd file (used to store command line)
 # (6) No dir/.target.cmd file and target not listed in $(targets)
 #     This is a good hint that there is a bug in the kbuild file
 ifeq ($(KBUILD_VERBOSE),2)
 why =                                                                        \
     $(if $(filter $@, $(PHONY)),- due to target is PHONY,                    \
         $(if $(wildcard $@),                                                 \
             $(if $(strip $(any-prereq)),- due to: $(any-prereq),             \
                 $(if $(arg-check),                                           \
                     $(if $(cmd_$@),- due to command line change,             \
                         $(if $(filter $@, $(targets)),                       \
                             - due to missing .cmd file,                      \
                             - due to $(notdir $@) not in $$(targets)         \
                          )                                                   \
                      )                                                       \
                  )                                                           \
              ),                                                              \
              - due to target missing                                         \
          )                                                                   \
      )

 echo-why = $(call escsq, $(strip $(why)))
 endif

 ###############################################################################
 #
 # When a Kconfig string contains a filename, it is suitable for
 # passing to shell commands. It is surrounded by double-quotes, and
 # any double-quotes or backslashes within it are escaped by
 # backslashes.
 #
 # This is no use for dependencies or $(wildcard). We need to strip the
 # surrounding quotes and the escaping from quotes and backslashes, and
 # we *do* need to escape any spaces in the string. So, for example:
 #
 # Usage: $(eval $(call config_filename,FOO))
 #
 # Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
 # transformed as described above to be suitable for use within the
 # makefile.
 #
 # Also, if the filename is a relative filename and exists in the source
 # tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
 # be prefixed to *both* command invocation and dependencies.
 #
 # Note: We also print the filenames in the quiet_cmd_foo text, and
 # perhaps ought to have a version specially escaped for that purpose.
 # But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
 # enough.  It'll strip the quotes in the common case where there's no
 # space and it's a simple filename, and it'll retain the quotes when
 # there's a space. There are some esoteric cases in which it'll print
 # the wrong thing, but we don't really care. The actual dependencies
 # and commands *do* get it right, with various combinations of single
 # and double quotes, backslashes and spaces in the filenames.
 #
 ###############################################################################
 #
 space_escape := %%%SPACE%%%
 #
 define config_filename
 ifneq ($$(CONFIG_$(1)),"")
 $(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
 ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
 else
 ifeq ($$(wildcard $$($(1)_FILENAME)),)
 ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
 $(1)_SRCPREFIX := $(srctree)/
 endif
 endif
 endif
 endif
 endef
 #
 ###############################################################################
	####
	# kbuild: Generic definitions

	# Convenient variables
	comma := ,
	quote := "
	squote := '
	empty :=
	space := $(empty) $(empty)
	pound := \#

	###
	# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
	dot-target = $(dir $@).$(notdir $@)

	###
	# The temporary file to save gcc -MD generated dependencies must not
	# contain a comma
	depfile = $(subst $(comma),_,$(dot-target).d)

	###
	# filename of target with directory and extension stripped
	basetarget = $(basename $(notdir $@))

	###
	# filename of first prerequisite with directory and extension stripped
	baseprereq = $(basename $(notdir $<))

	###
	# Escape single quote for use in echo statements
	escsq = $(subst $(squote),'\$(squote)',$1)

	###
	# Easy method for doing a status message
	kecho := :
	quiet_kecho := echo
	silent_kecho := :
	kecho := $($(quiet)kecho)

	###
	# filechk is used to check if the content of a generated file is updated.
	# Sample usage:
	# define filechk_sample
	# echo $KERNELRELEASE
	# endef
	# version.h : Makefile
	# $(call filechk,sample)
	# The rule defined shall write to stdout the content of the new file.
	# The existing file will be compared with the new one.
	# - If no file exist it is created
	# - If the content differ the new file is used
	# - If they are equal no change, and no timestamp update
	# - stdin is piped in from the first prerequisite ($<) so one has
	# to specify a valid file as first prerequisite (often the kbuild file)
	define filechk
	$(Q)set -e; \
	$(kecho) ' CHK $@'; \
	mkdir -p $(dir $@); \
	$(filechk_$(1)) < $< > $@.tmp; \
	if [ -r $@ ] && cmp -s $@ $@.tmp; then \
	rm -f $@.tmp; \
	else \
	$(kecho) ' UPD $@'; \
	mv -f $@.tmp $@; \
	fi
	endef

	######
	# gcc support functions
	# See documentation in Documentation/kbuild/makefiles.txt

	# cc-cross-prefix
	# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
	# Return first prefix where a prefix$(CC) is found in PATH.
	# If no $(CC) found in PATH with listed prefixes return nothing
	cc-cross-prefix = \
	$(word 1, $(foreach c,$(1), \
	$(shell set -e; \
	if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \
	echo $(c); \
	fi)))

	# output directory for tests below
	TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)

	# try-run
	# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
	# Exit code chooses option. "$$TMP" is can be used as temporary file and
	# is automatically cleaned up.
	try-run = $(shell set -e; \
	TMP="$(TMPOUT).$$$$.tmp"; \
	TMPO="$(TMPOUT).$$$$.o"; \
	if ($(1)) >/dev/null 2>&1; \
	then echo "$(2)"; \
	else echo "$(3)"; \
	fi; \
	rm -f "$$TMP" "$$TMPO")

	# as-option
	# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)

	as-option = $(call try-run,\
	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))

	# as-instr
	# Usage: cflags-y += $(call as-instr,instr,option1,option2)

	as-instr = $(call try-run,\
	printf "%b\n" "$(1)" \| $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))

	# cc-option
	# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)

	cc-option = $(call try-run,\
	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))

	# cc-option-yn
	# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
	cc-option-yn = $(call try-run,\
	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)

	# cc-option-align
	# Prefix align with either -falign or -malign
	cc-option-align = $(subst -functions=0,,\
	$(call cc-option,-falign-functions=0,-malign-functions=0))

	# cc-disable-warning
	# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
	cc-disable-warning = $(call try-run,\
	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))

	# cc-name
	# Expands to either gcc or clang
	cc-name = $(shell $(CC) -v 2>&1 \| grep -q "clang version" && echo clang \|\| echo gcc)

	# cc-version
	cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))

	# cc-fullversion
	cc-fullversion = $(shell $(CONFIG_SHELL) \
	$(srctree)/scripts/gcc-version.sh -p $(CC))

	# cc-ifversion
	# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
	cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) \|\| echo $(4))

	# cc-ldoption
	# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
	cc-ldoption = $(call try-run,\
	$(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))

	# ld-option
	# Usage: LDFLAGS += $(call ld-option, -X)
	ld-option = $(call try-run,\
	$(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))

	# ar-option
	# Usage: KBUILD_ARFLAGS := $(call ar-option,D)
	# Important: no spaces around options
	ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))

	# ld-version
	# Note this is mainly for HJ Lu's 3 number binutil versions
	ld-version = $(shell $(LD) --version \| $(srctree)/scripts/ld-version.sh)

	# ld-ifversion
	# Usage: $(call ld-ifversion, -ge, 22252, y)
	ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) \|\| echo $(4))

	######

	###
	# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
	# Usage:
	# $(Q)$(MAKE) $(build)=dir
	build := -f $(srctree)/scripts/Makefile.build obj

	###
	# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
	# Usage:
	# $(Q)$(MAKE) $(modbuiltin)=dir
	modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj

	###
	# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
	# Usage:
	# $(Q)$(MAKE) $(dtbinst)=dir
	dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj

	###
	# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
	# Usage:
	# $(Q)$(MAKE) $(clean)=dir
	clean := -f $(srctree)/scripts/Makefile.clean obj

	###
	# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
	# Usage:
	# $(Q)$(MAKE) $(hdr-inst)=dir
	hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj

	# Prefix -I with $(srctree) if it is not an absolute path.
	# skip if -I has no parameter
	addtree = $(if $(patsubst -I%,%,$(1)), \
	$(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1))

	# Find all -I options and call addtree
	flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))

	# echo command.
	# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
	echo-cmd = $(if $($(quiet)cmd_$(1)),\
	echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)

	# printing commands
	cmd = @$(echo-cmd) $(cmd_$(1))

	# Add $(obj)/ for paths that are not absolute
	objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))

	###
	# if_changed - execute command if any prerequisite is newer than
	# target, or command line has changed
	# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
	# including used config symbols
	# if_changed_rule - as if_changed but execute rule instead
	# See Documentation/kbuild/makefiles.txt for more info

	ifneq ($(KBUILD_NOCMDDEP),1)
	# Check if both arguments has same arguments. Result is empty string if equal.
	# User may override this check using make KBUILD_NOCMDDEP=1
	arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
	$(filter-out $(cmd_$@), $(cmd_$(1))) )
	else
	arg-check = $(if $(strip $(cmd_$@)),,1)
	endif

	# Replace >$< with >$$< to preserve $ when reloading the .cmd file
	# (needed for make)
	# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
	# (needed for make)
	# Replace >'< with >'\''< to be able to enclose the whole string in '...'
	# (needed for the shell)
	make-cmd = $(call escsq,$(subst $(pound),$$(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 $^),$^)

	# Execute command if command has changed or prerequisite(s) are updated.
	#
	if_changed = $(if $(strip $(any-prereq) $(arg-check)), \
	@set -e; \
	$(echo-cmd) $(cmd_$(1)); \
	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) $(arg-check) ), \
	@set -e; \
	$(echo-cmd) $(cmd_$(1)); \
	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
	rm -f $(depfile); \
	mv -f $(dot-target).tmp $(dot-target).cmd)

	# 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) $(arg-check) ), \
	@set -e; \
	$(rule_$(1)))

	###
	# why - tell why a a target got build
	# enabled by make V=2
	# Output (listed in the order they are checked):
	# (1) - due to target is PHONY
	# (2) - due to target missing
	# (3) - due to: file1.h file2.h
	# (4) - due to command line change
	# (5) - due to missing .cmd file
	# (6) - due to target not in $(targets)
	# (1) PHONY targets are always build
	# (2) No target, so we better build it
	# (3) Prerequisite is newer than target
	# (4) The command line stored in the file named dir/.target.cmd
	# differed from actual command line. This happens when compiler
	# options changes
	# (5) No dir/.target.cmd file (used to store command line)
	# (6) No dir/.target.cmd file and target not listed in $(targets)
	# This is a good hint that there is a bug in the kbuild file
	ifeq ($(KBUILD_VERBOSE),2)
	why = \
	$(if $(filter $@, $(PHONY)),- due to target is PHONY, \
	$(if $(wildcard $@), \
	$(if $(strip $(any-prereq)),- due to: $(any-prereq), \
	$(if $(arg-check), \
	$(if $(cmd_$@),- due to command line change, \
	$(if $(filter $@, $(targets)), \
	- due to missing .cmd file, \
	- due to $(notdir $@) not in $$(targets) \
	) \
	) \
	) \
	), \
	- due to target missing \
	) \
	)

	echo-why = $(call escsq, $(strip $(why)))
	endif

	###############################################################################
	#
	# When a Kconfig string contains a filename, it is suitable for
	# passing to shell commands. It is surrounded by double-quotes, and
	# any double-quotes or backslashes within it are escaped by
	# backslashes.
	#
	# This is no use for dependencies or $(wildcard). We need to strip the
	# surrounding quotes and the escaping from quotes and backslashes, and
	# we do need to escape any spaces in the string. So, for example:
	#
	# Usage: $(eval $(call config_filename,FOO))
	#
	# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
	# transformed as described above to be suitable for use within the
	# makefile.
	#
	# Also, if the filename is a relative filename and exists in the source
	# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
	# be prefixed to both command invocation and dependencies.
	#
	# Note: We also print the filenames in the quiet_cmd_foo text, and
	# perhaps ought to have a version specially escaped for that purpose.
	# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
	# enough. It'll strip the quotes in the common case where there's no
	# space and it's a simple filename, and it'll retain the quotes when
	# there's a space. There are some esoteric cases in which it'll print
	# the wrong thing, but we don't really care. The actual dependencies
	# and commands do get it right, with various combinations of single
	# and double quotes, backslashes and spaces in the filenames.
	#
	###############################################################################
	#
	space_escape := %%%SPACE%%%
	#
	define config_filename
	ifneq ($$(CONFIG_$(1)),"")
	$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
	ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
	else
	ifeq ($$(wildcard $$($(1)_FILENAME)),)
	ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
	$(1)_SRCPREFIX := $(srctree)/
	endif
	endif
	endif
	endif
	endef
	#
	###############################################################################