1#### 2# kbuild: Generic definitions 3 4# Convenient variables 5comma := , 6quote := " 7squote := ' 8empty := 9space := $(empty) $(empty) 10space_escape := _-_SPACE_-_ 11pound := \# 12 13### 14# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o 15dot-target = $(dir $@).$(notdir $@) 16 17### 18# The temporary file to save gcc -MD generated dependencies must not 19# contain a comma 20depfile = $(subst $(comma),_,$(dot-target).d) 21 22### 23# filename of target with directory and extension stripped 24basetarget = $(basename $(notdir $@)) 25 26### 27# filename of first prerequisite with directory and extension stripped 28baseprereq = $(basename $(notdir $<)) 29 30### 31# Escape single quote for use in echo statements 32escsq = $(subst $(squote),'\$(squote)',$1) 33 34### 35# Easy method for doing a status message 36 kecho := : 37 quiet_kecho := echo 38silent_kecho := : 39kecho := $($(quiet)kecho) 40 41### 42# filechk is used to check if the content of a generated file is updated. 43# Sample usage: 44# define filechk_sample 45# echo $KERNELRELEASE 46# endef 47# version.h : Makefile 48# $(call filechk,sample) 49# The rule defined shall write to stdout the content of the new file. 50# The existing file will be compared with the new one. 51# - If no file exist it is created 52# - If the content differ the new file is used 53# - If they are equal no change, and no timestamp update 54# - stdin is piped in from the first prerequisite ($<) so one has 55# to specify a valid file as first prerequisite (often the kbuild file) 56define filechk 57 $(Q)set -e; \ 58 $(kecho) ' CHK $@'; \ 59 mkdir -p $(dir $@); \ 60 $(filechk_$(1)) < $< > $@.tmp; \ 61 if [ -r $@ ] && cmp -s $@ $@.tmp; then \ 62 rm -f $@.tmp; \ 63 else \ 64 $(kecho) ' UPD $@'; \ 65 mv -f $@.tmp $@; \ 66 fi 67endef 68 69###### 70# gcc support functions 71# See documentation in Documentation/kbuild/makefiles.txt 72 73# cc-cross-prefix 74# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-) 75# Return first prefix where a prefix$(CC) is found in PATH. 76# If no $(CC) found in PATH with listed prefixes return nothing 77cc-cross-prefix = \ 78 $(word 1, $(foreach c,$(1), \ 79 $(shell set -e; \ 80 if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \ 81 echo $(c); \ 82 fi))) 83 84# output directory for tests below 85TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/) 86 87# try-run 88# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) 89# Exit code chooses option. "$$TMP" serves as a temporary file and is 90# automatically cleaned up. 91try-run = $(shell set -e; \ 92 TMP="$(TMPOUT).$$$$.tmp"; \ 93 TMPO="$(TMPOUT).$$$$.o"; \ 94 if ($(1)) >/dev/null 2>&1; \ 95 then echo "$(2)"; \ 96 else echo "$(3)"; \ 97 fi; \ 98 rm -f "$$TMP" "$$TMPO") 99 100# as-option 101# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) 102 103as-option = $(call try-run,\ 104 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2)) 105 106# as-instr 107# Usage: cflags-y += $(call as-instr,instr,option1,option2) 108 109as-instr = $(call try-run,\ 110 printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) 111 112# __cc-option 113# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) 114__cc-option = $(call try-run,\ 115 $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4)) 116 117# Do not attempt to build with gcc plugins during cc-option tests. 118# (And this uses delayed resolution so the flags will be up to date.) 119CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) 120 121# cc-option 122# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) 123 124cc-option = $(call __cc-option, $(CC),\ 125 $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2)) 126 127# hostcc-option 128# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) 129hostcc-option = $(call __cc-option, $(HOSTCC),\ 130 $(HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) 131 132# cc-option-yn 133# Usage: flag := $(call cc-option-yn,-march=winchip-c6) 134cc-option-yn = $(call try-run,\ 135 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) 136 137# cc-disable-warning 138# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) 139cc-disable-warning = $(call try-run,\ 140 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) 141 142# cc-name 143# Expands to either gcc or clang 144cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc) 145 146# __cc-version 147# Returns compiler version 148__cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/$(cc-name)-version.sh $(CC)) 149 150# __cc-fullversion 151# Returns full compiler version 152__cc-fullversion = $(shell $(CONFIG_SHELL) \ 153 $(srctree)/scripts/$(cc-name)-version.sh -p $(CC)) 154 155# __cc-ifversion 156# Matches compiler name and version 157# Usage: EXTRA_CFLAGS += $(call cc-if-name-version, gcc, -lt, 0402, -O1) 158__cc-ifversion = $(shell [ $(cc-name) = $(1) ] && [ $(__cc-version) $(2) $(3) ] && echo $(4) || echo $(5)) 159 160# __cc-if-fullversion 161# Matches compiler name and full version 162# Usage: EXTRA_CFLAGS += $(call cc-if-name-fullversion, gcc, -lt, 040502, -O1) 163__cc-if-fullversion = $(shell [ $(cc-name) = $(1) ] && [ $(__cc-fullversion) $(2) $(3) ] && echo $(4) || echo $(5)) 164 165# gcc-ifversion 166gcc-ifversion = $(call __cc-ifversion, gcc, $(1), $(2), $(3), $(4)) 167 168# gcc-if-fullversion 169gcc-if-fullversion = (call __cc-if-fullversion, gcc, $(1), $(2), $(3), $(4)) 170 171# clang-ifversion 172clang-ifversion = $(call __cc-ifversion, clang, $(1), $(2), $(3), $(4)) 173 174# clang-if-fullversion 175clang-if-fullversion = (call __cc-if-fullversion, clang, $(1), $(2), $(3), $(4)) 176 177# cc-version 178cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) 179 180# cc-fullversion 181cc-fullversion = $(shell $(CONFIG_SHELL) \ 182 $(srctree)/scripts/gcc-version.sh -p $(CC)) 183 184# backward compatibility 185cc-ifversion = $(gcc-ifversion) 186cc-if-fullversion = $(gcc-if-fullversion) 187 188# cc-if-fullversion 189# Usage: EXTRA_CFLAGS += $(call cc-if-fullversion, -lt, 040502, -O1) 190cc-if-fullversion = $(shell [ $(cc-fullversion) $(1) $(2) ] && echo $(3) || echo $(4)) 191 192# cc-ldoption 193# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 194cc-ldoption = $(call try-run,\ 195 $(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 196 197# ld-option 198# Usage: LDFLAGS += $(call ld-option, -X) 199ld-option = $(call try-run, $(LD) $(LDFLAGS) $(1) -v,$(1),$(2)) 200 201# ar-option 202# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 203# Important: no spaces around options 204ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 205 206# ld-name 207# Expands to either bfd or gold 208ld-name = $(shell $(LD) -v 2>&1 | grep -q "GNU gold" && echo gold || echo bfd) 209 210# ld-version 211# Note this is mainly for HJ Lu's 3 number binutil versions 212ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 213 214# ld-ifversion 215# Usage: $(call ld-ifversion, -ge, 22252, y) 216ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 217 218# __ld-ifversion 219# Usage: $(call __ld-ifversion, gold, -ge, 112000000, y) 220__ld-ifversion = $(shell [ $(ld-name) = $(1) ] && [ $(ld-version) $(2) $(3) ] && echo $(4) || echo $(5)) 221 222# bfd-ifversion 223# Usage: $(call bfd-ifversion, -ge, 227000000, y) 224bfd-ifversion = $(call __ld-ifversion, bfd, $(1), $(2), $(3), $(4)) 225 226# gold-ifversion 227# Usage: $(call gold-ifversion, -ge, 112000000, y) 228gold-ifversion = $(call __ld-ifversion, gold, $(1), $(2), $(3), $(4)) 229 230###### 231 232### 233# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 234# Usage: 235# $(Q)$(MAKE) $(build)=dir 236build := -f $(srctree)/scripts/Makefile.build obj 237 238### 239# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 240# Usage: 241# $(Q)$(MAKE) $(modbuiltin)=dir 242modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 243 244### 245# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 246# Usage: 247# $(Q)$(MAKE) $(dtbinst)=dir 248dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj 249 250### 251# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 252# Usage: 253# $(Q)$(MAKE) $(clean)=dir 254clean := -f $(srctree)/scripts/Makefile.clean obj 255 256### 257# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 258# Usage: 259# $(Q)$(MAKE) $(hdr-inst)=dir 260hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 261 262# Prefix -I with $(srctree) if it is not an absolute path. 263# skip if -I has no parameter 264addtree = $(if $(patsubst -I%,%,$(1)), \ 265$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1))) 266 267# Find all -I options and call addtree 268flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 269 270# echo command. 271# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 272echo-cmd = $(if $($(quiet)cmd_$(1)),\ 273 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 274 275# printing commands 276cmd = @$(echo-cmd) $(cmd_$(1)) 277 278# Add $(obj)/ for paths that are not absolute 279objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 280 281### 282# if_changed - execute command if any prerequisite is newer than 283# target, or command line has changed 284# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 285# including used config symbols 286# if_changed_rule - as if_changed but execute rule instead 287# See Documentation/kbuild/makefiles.txt for more info 288 289ifneq ($(KBUILD_NOCMDDEP),1) 290# Check if both arguments are the same including their order. Result is empty 291# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 292arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 293 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 294else 295arg-check = $(if $(strip $(cmd_$@)),,1) 296endif 297 298# Replace >$< with >$$< to preserve $ when reloading the .cmd file 299# (needed for make) 300# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file 301# (needed for make) 302# Replace >'< with >'\''< to be able to enclose the whole string in '...' 303# (needed for the shell) 304make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) 305 306# Find any prerequisites that is newer than target or that does not exist. 307# PHONY targets skipped in both cases. 308any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 309 310# Execute command if command has changed or prerequisite(s) are updated. 311if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 312 @set -e; \ 313 $(echo-cmd) $(cmd_$(1)); \ 314 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 315 316# Execute the command and also postprocess generated .d dependencies file. 317if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ 318 @set -e; \ 319 $(cmd_and_fixdep), @:) 320 321ifndef CONFIG_TRIM_UNUSED_KSYMS 322 323cmd_and_fixdep = \ 324 $(echo-cmd) $(cmd_$(1)); \ 325 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ 326 rm -f $(depfile); \ 327 mv -f $(dot-target).tmp $(dot-target).cmd; 328 329else 330 331# Filter out exported kernel symbol names from the preprocessor output. 332# See also __KSYM_DEPS__ in include/linux/export.h. 333# We disable the depfile generation here, so as not to overwrite the existing 334# depfile while fixdep is parsing it. 335flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1))) 336ksym_dep_filter = \ 337 case "$(1)" in \ 338 cc_*_c|cpp_i_c) \ 339 $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \ 340 as_*_S|cpp_s_S) \ 341 $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \ 342 boot*|build*|cpp_its_S|*cpp_lds_S|dtc|host*|vdso*) : ;; \ 343 *) echo "Don't know how to preprocess $(1)" >&2; false ;; \ 344 esac | tr ";" "\n" | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p' 345 346cmd_and_fixdep = \ 347 $(echo-cmd) $(cmd_$(1)); \ 348 $(ksym_dep_filter) | \ 349 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \ 350 > $(dot-target).tmp; \ 351 rm -f $(depfile); \ 352 mv -f $(dot-target).tmp $(dot-target).cmd; 353 354endif 355 356# Usage: $(call if_changed_rule,foo) 357# Will check if $(cmd_foo) or any of the prerequisites changed, 358# and if so will execute $(rule_foo). 359if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \ 360 @set -e; \ 361 $(rule_$(1)), @:) 362 363### 364# why - tell why a target got built 365# enabled by make V=2 366# Output (listed in the order they are checked): 367# (1) - due to target is PHONY 368# (2) - due to target missing 369# (3) - due to: file1.h file2.h 370# (4) - due to command line change 371# (5) - due to missing .cmd file 372# (6) - due to target not in $(targets) 373# (1) PHONY targets are always build 374# (2) No target, so we better build it 375# (3) Prerequisite is newer than target 376# (4) The command line stored in the file named dir/.target.cmd 377# differed from actual command line. This happens when compiler 378# options changes 379# (5) No dir/.target.cmd file (used to store command line) 380# (6) No dir/.target.cmd file and target not listed in $(targets) 381# This is a good hint that there is a bug in the kbuild file 382ifeq ($(KBUILD_VERBOSE),2) 383why = \ 384 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 385 $(if $(wildcard $@), \ 386 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 387 $(if $(arg-check), \ 388 $(if $(cmd_$@),- due to command line change, \ 389 $(if $(filter $@, $(targets)), \ 390 - due to missing .cmd file, \ 391 - due to $(notdir $@) not in $$(targets) \ 392 ) \ 393 ) \ 394 ) \ 395 ), \ 396 - due to target missing \ 397 ) \ 398 ) 399 400echo-why = $(call escsq, $(strip $(why))) 401endif 402 403############################################################################### 404# 405# When a Kconfig string contains a filename, it is suitable for 406# passing to shell commands. It is surrounded by double-quotes, and 407# any double-quotes or backslashes within it are escaped by 408# backslashes. 409# 410# This is no use for dependencies or $(wildcard). We need to strip the 411# surrounding quotes and the escaping from quotes and backslashes, and 412# we *do* need to escape any spaces in the string. So, for example: 413# 414# Usage: $(eval $(call config_filename,FOO)) 415# 416# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 417# transformed as described above to be suitable for use within the 418# makefile. 419# 420# Also, if the filename is a relative filename and exists in the source 421# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 422# be prefixed to *both* command invocation and dependencies. 423# 424# Note: We also print the filenames in the quiet_cmd_foo text, and 425# perhaps ought to have a version specially escaped for that purpose. 426# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 427# enough. It'll strip the quotes in the common case where there's no 428# space and it's a simple filename, and it'll retain the quotes when 429# there's a space. There are some esoteric cases in which it'll print 430# the wrong thing, but we don't really care. The actual dependencies 431# and commands *do* get it right, with various combinations of single 432# and double quotes, backslashes and spaces in the filenames. 433# 434############################################################################### 435# 436define config_filename 437ifneq ($$(CONFIG_$(1)),"") 438$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 439ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 440else 441ifeq ($$(wildcard $$($(1)_FILENAME)),) 442ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 443$(1)_SRCPREFIX := $(srctree)/ 444endif 445endif 446endif 447endif 448endef 449# 450############################################################################### 451 452# delete partially updated (i.e. corrupted) files on error 453.DELETE_ON_ERROR: 454