1#### 2# kbuild: Generic definitions 3 4# Convenient variables 5comma := , 6quote := " 7squote := ' 8empty := 9space := $(empty) $(empty) 10space_escape := _-_SPACE_-_ 11 12### 13# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o 14dot-target = $(dir $@).$(notdir $@) 15 16### 17# The temporary file to save gcc -MD generated dependencies must not 18# contain a comma 19depfile = $(subst $(comma),_,$(dot-target).d) 20 21### 22# filename of target with directory and extension stripped 23basetarget = $(basename $(notdir $@)) 24 25### 26# filename of first prerequisite with directory and extension stripped 27baseprereq = $(basename $(notdir $<)) 28 29### 30# Escape single quote for use in echo statements 31escsq = $(subst $(squote),'\$(squote)',$1) 32 33### 34# Easy method for doing a status message 35 kecho := : 36 quiet_kecho := echo 37silent_kecho := : 38kecho := $($(quiet)kecho) 39 40### 41# filechk is used to check if the content of a generated file is updated. 42# Sample usage: 43# define filechk_sample 44# echo $KERNELRELEASE 45# endef 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) 55define filechk 56 $(Q)set -e; \ 57 $(kecho) ' CHK $@'; \ 58 mkdir -p $(dir $@); \ 59 $(filechk_$(1)) < $< > $@.tmp; \ 60 if [ -r $@ ] && cmp -s $@ $@.tmp; then \ 61 rm -f $@.tmp; \ 62 else \ 63 $(kecho) ' UPD $@'; \ 64 mv -f $@.tmp $@; \ 65 fi 66endef 67 68###### 69# gcc support functions 70# See documentation in Documentation/kbuild/makefiles.txt 71 72# cc-cross-prefix 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 76cc-cross-prefix = \ 77 $(word 1, $(foreach c,$(1), \ 78 $(shell set -e; \ 79 if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \ 80 echo $(c); \ 81 fi))) 82 83# output directory for tests below 84TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/) 85 86# try-run 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. 90try-run = $(shell set -e; \ 91 TMP="$(TMPOUT).$$$$.tmp"; \ 92 TMPO="$(TMPOUT).$$$$.o"; \ 93 if ($(1)) >/dev/null 2>&1; \ 94 then echo "$(2)"; \ 95 else echo "$(3)"; \ 96 fi; \ 97 rm -f "$$TMP" "$$TMPO") 98 99# as-option 100# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) 101 102as-option = $(call try-run,\ 103 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2)) 104 105# as-instr 106# Usage: cflags-y += $(call as-instr,instr,option1,option2) 107 108as-instr = $(call try-run,\ 109 printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) 110 111# __cc-option 112# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) 113__cc-option = $(call try-run,\ 114 $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4)) 115 116# Do not attempt to build with gcc plugins during cc-option tests. 117# (And this uses delayed resolution so the flags will be up to date.) 118CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) 119 120# cc-option 121# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) 122 123cc-option = $(call __cc-option, $(CC),\ 124 $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2)) 125 126# hostcc-option 127# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) 128hostcc-option = $(call __cc-option, $(HOSTCC),\ 129 $(HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) 130 131# cc-option-yn 132# Usage: flag := $(call cc-option-yn,-march=winchip-c6) 133cc-option-yn = $(call try-run,\ 134 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) 135 136# cc-option-align 137# Prefix align with either -falign or -malign 138cc-option-align = $(subst -functions=0,,\ 139 $(call cc-option,-falign-functions=0,-malign-functions=0)) 140 141# cc-disable-warning 142# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) 143cc-disable-warning = $(call try-run,\ 144 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) 145 146# cc-name 147# Expands to either gcc or clang 148cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc) 149 150# __cc-version 151# Returns compiler version 152__cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/$(cc-name)-version.sh $(CC)) 153 154# __cc-fullversion 155# Returns full compiler version 156__cc-fullversion = $(shell $(CONFIG_SHELL) \ 157 $(srctree)/scripts/$(cc-name)-version.sh -p $(CC)) 158 159# __cc-ifversion 160# Matches compiler name and version 161# Usage: EXTRA_CFLAGS += $(call cc-if-name-version, gcc, -lt, 0402, -O1) 162__cc-ifversion = $(shell [ $(cc-name) = $(1) ] && [ $(__cc-version) $(2) $(3) ] && echo $(4) || echo $(5)) 163 164# __cc-if-fullversion 165# Matches compiler name and full version 166# Usage: EXTRA_CFLAGS += $(call cc-if-name-fullversion, gcc, -lt, 040502, -O1) 167__cc-if-fullversion = $(shell [ $(cc-name) = $(1) ] && [ $(__cc-fullversion) $(2) $(3) ] && echo $(4) || echo $(5)) 168 169# gcc-ifversion 170gcc-ifversion = $(call __cc-ifversion, gcc, $(1), $(2), $(3), $(4)) 171 172# gcc-if-fullversion 173gcc-if-fullversion = (call __cc-if-fullversion, gcc, $(1), $(2), $(3), $(4)) 174 175# clang-ifversion 176clang-ifversion = $(call __cc-ifversion, clang, $(1), $(2), $(3), $(4)) 177 178# clang-if-fullversion 179clang-if-fullversion = (call __cc-if-fullversion, clang, $(1), $(2), $(3), $(4)) 180 181# cc-version 182cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) 183 184# cc-fullversion 185cc-fullversion = $(shell $(CONFIG_SHELL) \ 186 $(srctree)/scripts/gcc-version.sh -p $(CC)) 187 188# backward compatibility 189cc-ifversion = $(gcc-ifversion) 190cc-if-fullversion = $(gcc-if-fullversion) 191 192# cc-ldoption 193# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 194cc-ldoption = $(call try-run,\ 195 $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 196 197# ld-option 198# Usage: LDFLAGS += $(call ld-option, -X) 199ld-option = $(call try-run,\ 200 $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2)) 201 202# ar-option 203# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 204# Important: no spaces around options 205ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 206 207# ld-name 208# Expands to either bfd or gold 209ld-name = $(shell $(LD) -v 2>&1 | grep -q "GNU gold" && echo gold || echo bfd) 210 211# ld-version 212# Note this is mainly for HJ Lu's 3 number binutil versions 213ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 214 215# ld-ifversion 216# Usage: $(call ld-ifversion, -ge, 22252, y) 217ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 218 219# __ld-ifversion 220# Usage: $(call __ld-ifversion, gold, -ge, 112000000, y) 221__ld-ifversion = $(shell [ $(ld-name) = $(1) ] && [ $(ld-version) $(2) $(3) ] && echo $(4) || echo $(5)) 222 223# bfd-ifversion 224# Usage: $(call bfd-ifversion, -ge, 227000000, y) 225bfd-ifversion = $(call __ld-ifversion, bfd, $(1), $(2), $(3), $(4)) 226 227# gold-ifversion 228# Usage: $(call gold-ifversion, -ge, 112000000, y) 229gold-ifversion = $(call __ld-ifversion, gold, $(1), $(2), $(3), $(4)) 230 231###### 232 233### 234# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 235# Usage: 236# $(Q)$(MAKE) $(build)=dir 237build := -f $(srctree)/scripts/Makefile.build obj 238 239### 240# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 241# Usage: 242# $(Q)$(MAKE) $(modbuiltin)=dir 243modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 244 245### 246# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 247# Usage: 248# $(Q)$(MAKE) $(dtbinst)=dir 249dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj 250 251### 252# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 253# Usage: 254# $(Q)$(MAKE) $(clean)=dir 255clean := -f $(srctree)/scripts/Makefile.clean obj 256 257### 258# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 259# Usage: 260# $(Q)$(MAKE) $(hdr-inst)=dir 261hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 262 263# Prefix -I with $(srctree) if it is not an absolute path. 264# skip if -I has no parameter 265addtree = $(if $(patsubst -I%,%,$(1)), \ 266$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1))) 267 268# Find all -I options and call addtree 269flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 270 271# echo command. 272# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 273echo-cmd = $(if $($(quiet)cmd_$(1)),\ 274 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 275 276# printing commands 277cmd = @$(echo-cmd) $(cmd_$(1)) 278 279# Add $(obj)/ for paths that are not absolute 280objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 281 282### 283# if_changed - execute command if any prerequisite is newer than 284# target, or command line has changed 285# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 286# including used config symbols 287# if_changed_rule - as if_changed but execute rule instead 288# See Documentation/kbuild/makefiles.txt for more info 289 290ifneq ($(KBUILD_NOCMDDEP),1) 291# Check if both arguments are the same including their order. Result is empty 292# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 293arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 294 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 295else 296arg-check = $(if $(strip $(cmd_$@)),,1) 297endif 298 299# Replace >$< with >$$< to preserve $ when reloading the .cmd file 300# (needed for make) 301# Replace >#< with >\#< to avoid starting a comment in the .cmd file 302# (needed for make) 303# Replace >'< with >'\''< to be able to enclose the whole string in '...' 304# (needed for the shell) 305make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1))))) 306 307# Find any prerequisites that is newer than target or that does not exist. 308# PHONY targets skipped in both cases. 309any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 310 311# Execute command if command has changed or prerequisite(s) are updated. 312# 313if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 314 @set -e; \ 315 $(echo-cmd) $(cmd_$(1)); \ 316 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 317 318# Execute the command and also postprocess generated .d dependencies file. 319if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ 320 @set -e; \ 321 $(cmd_and_fixdep), @:) 322 323ifndef CONFIG_TRIM_UNUSED_KSYMS 324 325cmd_and_fixdep = \ 326 $(echo-cmd) $(cmd_$(1)); \ 327 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ 328 rm -f $(depfile); \ 329 mv -f $(dot-target).tmp $(dot-target).cmd; 330 331else 332 333# Filter out exported kernel symbol names from the preprocessor output. 334# See also __KSYM_DEPS__ in include/linux/export.h. 335# We disable the depfile generation here, so as not to overwrite the existing 336# depfile while fixdep is parsing it. 337flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1))) 338ksym_dep_filter = \ 339 case "$(1)" in \ 340 cc_*_c|cpp_i_c) \ 341 $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \ 342 as_*_S|cpp_s_S) \ 343 $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \ 344 boot*|build*|*cpp_lds_S|dtc|host*|vdso*) : ;; \ 345 *) echo "Don't know how to preprocess $(1)" >&2; false ;; \ 346 esac | tr ";" "\n" | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p' 347 348cmd_and_fixdep = \ 349 $(echo-cmd) $(cmd_$(1)); \ 350 $(ksym_dep_filter) | \ 351 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \ 352 > $(dot-target).tmp; \ 353 rm -f $(depfile); \ 354 mv -f $(dot-target).tmp $(dot-target).cmd; 355 356endif 357 358# Usage: $(call if_changed_rule,foo) 359# Will check if $(cmd_foo) or any of the prerequisites changed, 360# and if so will execute $(rule_foo). 361if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \ 362 @set -e; \ 363 $(rule_$(1)), @:) 364 365### 366# why - tell why a a target got build 367# enabled by make V=2 368# Output (listed in the order they are checked): 369# (1) - due to target is PHONY 370# (2) - due to target missing 371# (3) - due to: file1.h file2.h 372# (4) - due to command line change 373# (5) - due to missing .cmd file 374# (6) - due to target not in $(targets) 375# (1) PHONY targets are always build 376# (2) No target, so we better build it 377# (3) Prerequisite is newer than target 378# (4) The command line stored in the file named dir/.target.cmd 379# differed from actual command line. This happens when compiler 380# options changes 381# (5) No dir/.target.cmd file (used to store command line) 382# (6) No dir/.target.cmd file and target not listed in $(targets) 383# This is a good hint that there is a bug in the kbuild file 384ifeq ($(KBUILD_VERBOSE),2) 385why = \ 386 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 387 $(if $(wildcard $@), \ 388 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 389 $(if $(arg-check), \ 390 $(if $(cmd_$@),- due to command line change, \ 391 $(if $(filter $@, $(targets)), \ 392 - due to missing .cmd file, \ 393 - due to $(notdir $@) not in $$(targets) \ 394 ) \ 395 ) \ 396 ) \ 397 ), \ 398 - due to target missing \ 399 ) \ 400 ) 401 402echo-why = $(call escsq, $(strip $(why))) 403endif 404 405############################################################################### 406# 407# When a Kconfig string contains a filename, it is suitable for 408# passing to shell commands. It is surrounded by double-quotes, and 409# any double-quotes or backslashes within it are escaped by 410# backslashes. 411# 412# This is no use for dependencies or $(wildcard). We need to strip the 413# surrounding quotes and the escaping from quotes and backslashes, and 414# we *do* need to escape any spaces in the string. So, for example: 415# 416# Usage: $(eval $(call config_filename,FOO)) 417# 418# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 419# transformed as described above to be suitable for use within the 420# makefile. 421# 422# Also, if the filename is a relative filename and exists in the source 423# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 424# be prefixed to *both* command invocation and dependencies. 425# 426# Note: We also print the filenames in the quiet_cmd_foo text, and 427# perhaps ought to have a version specially escaped for that purpose. 428# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 429# enough. It'll strip the quotes in the common case where there's no 430# space and it's a simple filename, and it'll retain the quotes when 431# there's a space. There are some esoteric cases in which it'll print 432# the wrong thing, but we don't really care. The actual dependencies 433# and commands *do* get it right, with various combinations of single 434# and double quotes, backslashes and spaces in the filenames. 435# 436############################################################################### 437# 438define config_filename 439ifneq ($$(CONFIG_$(1)),"") 440$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 441ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 442else 443ifeq ($$(wildcard $$($(1)_FILENAME)),) 444ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 445$(1)_SRCPREFIX := $(srctree)/ 446endif 447endif 448endif 449endif 450endef 451# 452############################################################################### 453