[linux.git] / scripts / Kbuild.include

####
# kbuild: Generic definitions

# Convenient variables
comma   := ,
squote  := '
empty   :=
space   := $(empty) $(empty)

###
# 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 $@))

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

###
# 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;				\
	echo '  CHK     $@';			\
	mkdir -p $(dir $@);			\
	$(filechk_$(1)) < $< > [email protected];		\
	if [ -r $@ ] && cmp -s $@ [email protected]; then	\
		rm -f [email protected];			\
	else					\
		echo '  UPD     $@';		\
		mv -f [email protected] $@;		\
	fi
endef

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

# 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).$$$$.tmp";	\
	if ($(1)) >/dev/null 2>&1;	\
	then echo "$(2)";		\
	else echo "$(3)";		\
	fi;				\
	rm -f "$$TMP")

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

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

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

as-instr = $(call try-run,\
	echo -e "$(1)" | $(CC) $(AFLAGS) -c -xassembler -o "$$TMP" -,$(2),$(3))

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

cc-option = $(call try-run,\
	$(CC) $(CFLAGS) $(1) -S -xc /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) $(CFLAGS) $(1) -S -xc /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-version
# Usage gcc-ver := $(call cc-version,$(CC))
cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))

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

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

######

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

# Prefix -I with $(srctree) if it is not an absolute path.
addtree = $(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))) )
endif

# >'< substitution is for echo to work,
# >$< substitution to preserve $ when reloading .cmd file
# note: when using inline perl scripts [perl -e '...$$t=1;...']
# in $(cmd_xxx) double $$ your perl vars
make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(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));                                             \
	echo '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
Commit	Line	Data
8ec4b4ff SR	1	####
	2	# kbuild: Generic definitions
	3
beda9f3a	4	# Convenient variables
8ec4b4ff	5	comma := ,
d51bfb78	6	squote := '
8ec4b4ff SR	7	empty :=
	8	space := $(empty) $(empty)
	9
48f1f058 SR	10	###
	11	# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
	12	dot-target = $(dir $@).$(notdir $@)
	13
8ec4b4ff SR	14	###
	15	# The temporary file to save gcc -MD generated dependencies must not
	16	# contain a comma
48f1f058	17	depfile = $(subst $(comma),_,$(dot-target).d)
8ec4b4ff	18
5e8d780d SR	19	###
	20	# filename of target with directory and extension stripped
	21	basetarget = $(basename $(notdir $@))
	22
d51bfb78 SR	23	###
	24	# Escape single quote for use in echo statements
	25	escsq = $(subst $(squote),'\$(squote)',$1)
	26
8ec4b4ff SR	27	###
	28	# filechk is used to check if the content of a generated file is updated.
	29	# Sample usage:
	30	# define filechk_sample
	31	# echo $KERNELRELEASE
	32	# endef
	33	# version.h : Makefile
	34	# $(call filechk,sample)
	35	# The rule defined shall write to stdout the content of the new file.
	36	# The existing file will be compared with the new one.
	37	# - If no file exist it is created
	38	# - If the content differ the new file is used
	39	# - If they are equal no change, and no timestamp update
	40	# - stdin is piped in from the first prerequisite ($<) so one has
	41	# to specify a valid file as first prerequisite (often the kbuild file)
	42	define filechk
	43	$(Q)set -e; \
	44	echo ' CHK $@'; \
	45	mkdir -p $(dir $@); \
	46	$(filechk_$(1)) < $< > [email protected]; \
	47	if [ -r $@ ] && cmp -s $@ [email protected]; then \
	48	rm -f [email protected]; \
	49	else \
	50	echo ' UPD $@'; \
	51	mv -f [email protected] $@; \
	52	fi
	53	endef
	54
20a468b5	55	######
9d6e7a70	56	# gcc support functions
20a468b5 SR	57	# See documentation in Documentation/kbuild/makefiles.txt
20a468b5 SR	58
beda9f3a RZ	59	# output directory for tests below
	60	TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
	61
	62	# try-run
	63	# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
	64	# Exit code chooses option. "$$TMP" is can be used as temporary file and
	65	# is automatically cleaned up.
	66	try-run = $(shell set -e; \
	67	TMP="$(TMPOUT).$$$$.tmp"; \
	68	if ($(1)) >/dev/null 2>&1; \
	69	then echo "$(2)"; \
	70	else echo "$(3)"; \
	71	fi; \
	72	rm -f "$$TMP")
347a00fb	73
20a468b5	74	# as-option
bff288c1	75	# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
beda9f3a RZ	76
	77	as-option = $(call try-run,\
	78	$(CC) $(CFLAGS) $(1) -c -xassembler /dev/null -o "$$TMP",$(1),$(2))
20a468b5	79
e2414910	80	# as-instr
bff288c1	81	# Usage: cflags-y += $(call as-instr,instr,option1,option2)
beda9f3a RZ	82
	83	as-instr = $(call try-run,\
	84	echo -e "$(1)" \| $(CC) $(AFLAGS) -c -xassembler -o "$$TMP" -,$(2),$(3))
e2414910	85
20a468b5	86	# cc-option
bff288c1	87	# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
beda9f3a RZ	88
	89	cc-option = $(call try-run,\
	90	$(CC) $(CFLAGS) $(1) -S -xc /dev/null -o "$$TMP",$(1),$(2))
20a468b5 SR	91
20a468b5 SR	92	# cc-option-yn
bff288c1	93	# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
beda9f3a RZ	94	cc-option-yn = $(call try-run,\
beda9f3a RZ	95	$(CC) $(CFLAGS) $(1) -S -xc /dev/null -o "$$TMP",y,n)
20a468b5 SR	96
	97	# cc-option-align
	98	# Prefix align with either -falign or -malign
	99	cc-option-align = $(subst -functions=0,,\
beda9f3a	100	$(call cc-option,-falign-functions=0,-malign-functions=0))
20a468b5 SR	101
20a468b5 SR	102	# cc-version
bff288c1	103	# Usage gcc-ver := $(call cc-version,$(CC))
8eb3afe0	104	cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
20a468b5 SR	105
	106	# cc-ifversion
	107	# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
5de043f4	108	cc-ifversion = $(shell [ $(call cc-version, $(CC)) $(1) $(2) ] && echo $(3))
20a468b5	109
0b0bf7a3 RM	110	# ld-option
0b0bf7a3 RM	111	# Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
beda9f3a RZ	112	ld-option = $(call try-run,\
beda9f3a RZ	113	$(CC) $(1) -nostdlib -xc /dev/null -o "$$TMP",$(1),$(2))
5de043f4 OV	114
5de043f4 OV	115	######
0b0bf7a3	116
beda9f3a	117	###
8ec4b4ff SR	118	# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
	119	# Usage:
	120	# $(Q)$(MAKE) $(build)=dir
	121	build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj
	122
beda9f3a RZ	123	# Prefix -I with $(srctree) if it is not an absolute path.
beda9f3a RZ	124	addtree = $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1)
5de043f4	125
d9df92e2	126	# Find all -I options and call addtree
beda9f3a	127	flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
d9df92e2	128
5de043f4 OV	129	# echo command.
5de043f4 OV	130	# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
bff288c1	131	echo-cmd = $(if $($(quiet)cmd_$(1)),\
5de043f4 OV	132	echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
	133
	134	# printing commands
6176aa9a	135	cmd = @$(echo-cmd) $(cmd_$(1))
8ec4b4ff	136
5de043f4	137	# Add $(obj)/ for paths that are not absolute
bff288c1	138	objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
0a504f25	139
8ec4b4ff	140	###
5de043f4	141	# if_changed - execute command if any prerequisite is newer than
8ec4b4ff SR	142	# target, or command line has changed
	143	# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
	144	# including used config symbols
	145	# if_changed_rule - as if_changed but execute rule instead
	146	# See Documentation/kbuild/makefiles.txt for more info
	147
	148	ifneq ($(KBUILD_NOCMDDEP),1)
beda9f3a	149	# Check if both arguments has same arguments. Result is empty string if equal.
8ec4b4ff	150	# User may override this check using make KBUILD_NOCMDDEP=1
48f1f058 SR	151	arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
48f1f058 SR	152	$(filter-out $(cmd_$@), $(cmd_$(1))) )
8ec4b4ff SR	153	endif
8ec4b4ff SR	154
48f1f058 SR	155	# >'< substitution is for echo to work,
	156	# >$< substitution to preserve $ when reloading .cmd file
	157	# note: when using inline perl scripts [perl -e '...$$t=1;...']
	158	# in $(cmd_xxx) double $$ your perl vars
6176aa9a JB	159	make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1)))))
6176aa9a JB	160
48f1f058 SR	161	# Find any prerequisites that is newer than target or that does not exist.
	162	# PHONY targets skipped in both cases.
	163	any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
	164
5de043f4	165	# Execute command if command has changed or prerequisite(s) are updated.
4f193362	166	#
48f1f058 SR	167	if_changed = $(if $(strip $(any-prereq) $(arg-check)), \
	168	@set -e; \
	169	$(echo-cmd) $(cmd_$(1)); \
	170	echo 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd)
8ec4b4ff	171
5de043f4	172	# Execute the command and also postprocess generated .d dependencies file.
48f1f058 SR	173	if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \
	174	@set -e; \
	175	$(echo-cmd) $(cmd_$(1)); \
	176	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
	177	rm -f $(depfile); \
	178	mv -f $(dot-target).tmp $(dot-target).cmd)
8ec4b4ff SR	179
8ec4b4ff SR	180	# Usage: $(call if_changed_rule,foo)
beda9f3a RZ	181	# Will check if $(cmd_foo) or any of the prerequisites changed,
beda9f3a RZ	182	# and if so will execute $(rule_foo).
48f1f058 SR	183	if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \
	184	@set -e; \
	185	$(rule_$(1)))
	186
45d506bd SR	187	###
	188	# why - tell why a a target got build
	189	# enabled by make V=2
	190	# Output (listed in the order they are checked):
	191	# (1) - due to target is PHONY
	192	# (2) - due to target missing
	193	# (3) - due to: file1.h file2.h
	194	# (4) - due to command line change
	195	# (5) - due to missing .cmd file
	196	# (6) - due to target not in $(targets)
	197	# (1) PHONY targets are always build
	198	# (2) No target, so we better build it
	199	# (3) Prerequisite is newer than target
	200	# (4) The command line stored in the file named dir/.target.cmd
	201	# differed from actual command line. This happens when compiler
	202	# options changes
	203	# (5) No dir/.target.cmd file (used to store command line)
	204	# (6) No dir/.target.cmd file and target not listed in $(targets)
	205	# This is a good hint that there is a bug in the kbuild file
	206	ifeq ($(KBUILD_VERBOSE),2)
	207	why = \
	208	$(if $(filter $@, $(PHONY)),- due to target is PHONY, \
	209	$(if $(wildcard $@), \
	210	$(if $(strip $(any-prereq)),- due to: $(any-prereq), \
	211	$(if $(arg-check), \
	212	$(if $(cmd_$@),- due to command line change, \
	213	$(if $(filter $@, $(targets)), \
	214	- due to missing .cmd file, \
	215	- due to $(notdir $@) not in $$(targets) \
	216	) \
	217	) \
	218	) \
	219	), \
	220	- due to target missing \
	221	) \
	222	)
	223
	224	echo-why = $(call escsq, $(strip $(why)))
	225	endif