2 # kbuild: Generic definitions
9 space := $(empty) $(empty)
13 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
14 dot-target = $(dir $@).$(notdir $@)
17 # The temporary file to save gcc -MD generated dependencies must not
19 depfile = $(subst $(comma),_,$(dot-target).d)
22 # filename of target with directory and extension stripped
23 basetarget = $(basename $(notdir $@))
26 # filename of first prerequisite with directory and extension stripped
27 baseprereq = $(basename $(notdir $<))
30 # Escape single quote for use in echo statements
31 escsq = $(subst $(squote),'\$(squote)',$1)
34 # Easy method for doing a status message
38 kecho := $($(quiet)kecho)
41 # filechk is used to check if the content of a generated file is updated.
43 # define filechk_sample
46 # version.h : Makefile
47 # $(call filechk,sample)
48 # The rule defined shall write to stdout the content of the new file.
49 # The existing file will be compared with the new one.
50 # - If no file exist it is created
51 # - If the content differ the new file is used
52 # - If they are equal no change, and no timestamp update
53 # - stdin is piped in from the first prerequisite ($<) so one has
54 # to specify a valid file as first prerequisite (often the kbuild file)
59 $(filechk_$(1)) < $< > $@.tmp; \
60 if [ -r $@ ] && cmp -s $@ $@.tmp; then \
69 # gcc support functions
70 # See documentation in Documentation/kbuild/makefiles.txt
73 # Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
74 # Return first prefix where a prefix$(CC) is found in PATH.
75 # If no $(CC) found in PATH with listed prefixes return nothing
77 $(word 1, $(foreach c,$(1), \
79 if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \
83 # output directory for tests below
84 TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
87 # Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
88 # Exit code chooses option. "$$TMP" is can be used as temporary file and
89 # is automatically cleaned up.
90 try-run = $(shell set -e; \
91 TMP="$(TMPOUT).$$$$.tmp"; \
92 TMPO="$(TMPOUT).$$$$.o"; \
93 if ($(1)) >/dev/null 2>&1; \
97 rm -f "$$TMP" "$$TMPO")
100 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
102 as-option = $(call try-run,\
103 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
106 # Usage: cflags-y += $(call as-instr,instr,option1,option2)
108 as-instr = $(call try-run,\
109 printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
112 # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
114 cc-option = $(call try-run,\
115 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
118 # Usage: flag := $(call cc-option-yn,-march=winchip-c6)
119 cc-option-yn = $(call try-run,\
120 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
123 # Prefix align with either -falign or -malign
124 cc-option-align = $(subst -functions=0,,\
125 $(call cc-option,-falign-functions=0,-malign-functions=0))
128 # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
129 cc-disable-warning = $(call try-run,\
130 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
133 # Expands to either gcc or clang
134 cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)
137 cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
140 cc-fullversion = $(shell $(CONFIG_SHELL) \
141 $(srctree)/scripts/gcc-version.sh -p $(CC))
144 # Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
145 cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
148 # Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
149 cc-ldoption = $(call try-run,\
150 $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
153 # Usage: LDFLAGS += $(call ld-option, -X)
154 ld-option = $(call try-run,\
155 $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
158 # Usage: KBUILD_ARFLAGS := $(call ar-option,D)
159 # Important: no spaces around options
160 ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
163 # Note this is mainly for HJ Lu's 3 number binutil versions
164 ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
167 # Usage: $(call ld-ifversion, -ge, 22252, y)
168 ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))
173 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
175 # $(Q)$(MAKE) $(build)=dir
176 build := -f $(srctree)/scripts/Makefile.build obj
179 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
181 # $(Q)$(MAKE) $(modbuiltin)=dir
182 modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
185 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
187 # $(Q)$(MAKE) $(dtbinst)=dir
188 dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj
191 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
193 # $(Q)$(MAKE) $(clean)=dir
194 clean := -f $(srctree)/scripts/Makefile.clean obj
197 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
199 # $(Q)$(MAKE) $(hdr-inst)=dir
200 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
202 # Prefix -I with $(srctree) if it is not an absolute path.
203 # skip if -I has no parameter
204 addtree = $(if $(patsubst -I%,%,$(1)), \
205 $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1))
207 # Find all -I options and call addtree
208 flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
211 # Short version is used, if $(quiet) equals `quiet_', otherwise full one.
212 echo-cmd = $(if $($(quiet)cmd_$(1)),\
213 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
216 cmd = @$(echo-cmd) $(cmd_$(1))
218 # Add $(obj)/ for paths that are not absolute
219 objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
222 # if_changed - execute command if any prerequisite is newer than
223 # target, or command line has changed
224 # if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
225 # including used config symbols
226 # if_changed_rule - as if_changed but execute rule instead
227 # See Documentation/kbuild/makefiles.txt for more info
229 ifneq ($(KBUILD_NOCMDDEP),1)
230 # Check if both arguments has same arguments. Result is empty string if equal.
231 # User may override this check using make KBUILD_NOCMDDEP=1
232 arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
233 $(filter-out $(cmd_$@), $(cmd_$(1))) )
235 arg-check = $(if $(strip $(cmd_$@)),,1)
238 # Replace >$< with >$$< to preserve $ when reloading the .cmd file
240 # Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
242 # Replace >'< with >'\''< to be able to enclose the whole string in '...'
243 # (needed for the shell)
244 make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))
246 # Find any prerequisites that is newer than target or that does not exist.
247 # PHONY targets skipped in both cases.
248 any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
250 # Execute command if command has changed or prerequisite(s) are updated.
252 if_changed = $(if $(strip $(any-prereq) $(arg-check)), \
254 $(echo-cmd) $(cmd_$(1)); \
255 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd)
257 # Execute the command and also postprocess generated .d dependencies file.
258 if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \
260 $(echo-cmd) $(cmd_$(1)); \
261 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
263 mv -f $(dot-target).tmp $(dot-target).cmd)
265 # Usage: $(call if_changed_rule,foo)
266 # Will check if $(cmd_foo) or any of the prerequisites changed,
267 # and if so will execute $(rule_foo).
268 if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \
273 # why - tell why a a target got build
274 # enabled by make V=2
275 # Output (listed in the order they are checked):
276 # (1) - due to target is PHONY
277 # (2) - due to target missing
278 # (3) - due to: file1.h file2.h
279 # (4) - due to command line change
280 # (5) - due to missing .cmd file
281 # (6) - due to target not in $(targets)
282 # (1) PHONY targets are always build
283 # (2) No target, so we better build it
284 # (3) Prerequisite is newer than target
285 # (4) The command line stored in the file named dir/.target.cmd
286 # differed from actual command line. This happens when compiler
288 # (5) No dir/.target.cmd file (used to store command line)
289 # (6) No dir/.target.cmd file and target not listed in $(targets)
290 # This is a good hint that there is a bug in the kbuild file
291 ifeq ($(KBUILD_VERBOSE),2)
293 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \
294 $(if $(wildcard $@), \
295 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \
297 $(if $(cmd_$@),- due to command line change, \
298 $(if $(filter $@, $(targets)), \
299 - due to missing .cmd file, \
300 - due to $(notdir $@) not in $$(targets) \
305 - due to target missing \
309 echo-why = $(call escsq, $(strip $(why)))
312 ###############################################################################
314 # When a Kconfig string contains a filename, it is suitable for
315 # passing to shell commands. It is surrounded by double-quotes, and
316 # any double-quotes or backslashes within it are escaped by
319 # This is no use for dependencies or $(wildcard). We need to strip the
320 # surrounding quotes and the escaping from quotes and backslashes, and
321 # we *do* need to escape any spaces in the string. So, for example:
323 # Usage: $(eval $(call config_filename,FOO))
325 # Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
326 # transformed as described above to be suitable for use within the
329 # Also, if the filename is a relative filename and exists in the source
330 # tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
331 # be prefixed to *both* command invocation and dependencies.
333 # Note: We also print the filenames in the quiet_cmd_foo text, and
334 # perhaps ought to have a version specially escaped for that purpose.
335 # But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
336 # enough. It'll strip the quotes in the common case where there's no
337 # space and it's a simple filename, and it'll retain the quotes when
338 # there's a space. There are some esoteric cases in which it'll print
339 # the wrong thing, but we don't really care. The actual dependencies
340 # and commands *do* get it right, with various combinations of single
341 # and double quotes, backslashes and spaces in the filenames.
343 ###############################################################################
345 space_escape := %%%SPACE%%%
347 define config_filename
348 ifneq ($$(CONFIG_$(1)),"")
349 $(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
350 ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
352 ifeq ($$(wildcard $$($(1)_FILENAME)),)
353 ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
354 $(1)_SRCPREFIX := $(srctree)/
361 ###############################################################################