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 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))/).tmp_$$$$ 85 86# try-run 87# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) 88# Exit code chooses option. "$$TMP" serves as a temporary file and is 89# automatically cleaned up. 90try-run = $(shell set -e; \ 91 TMP=$(TMPOUT)/tmp; \ 92 TMPO=$(TMPOUT)/tmp.o; \ 93 mkdir -p $(TMPOUT); \ 94 trap "rm -rf $(TMPOUT)" EXIT; \ 95 if ($(1)) >/dev/null 2>&1; \ 96 then echo "$(2)"; \ 97 else echo "$(3)"; \ 98 fi) 99 100# as-option 101# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) 102 103as-option = $(call try-run,\ 104 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$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 $(KBUILD_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 147cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) 148 149# cc-fullversion 150cc-fullversion = $(shell $(CONFIG_SHELL) \ 151 $(srctree)/scripts/gcc-version.sh -p $(CC)) 152 153# cc-ifversion 154# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) 155cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4)) 156 157# cc-ldoption 158# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 159cc-ldoption = $(call try-run,\ 160 $(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 161 162# ld-option 163# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y) 164ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3)) 165 166# ar-option 167# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 168# Important: no spaces around options 169ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 170 171# ld-version 172# Note this is mainly for HJ Lu's 3 number binutil versions 173ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 174 175# ld-ifversion 176# Usage: $(call ld-ifversion, -ge, 22252, y) 177ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 178 179###### 180 181### 182# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 183# Usage: 184# $(Q)$(MAKE) $(build)=dir 185build := -f $(srctree)/scripts/Makefile.build obj 186 187### 188# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 189# Usage: 190# $(Q)$(MAKE) $(modbuiltin)=dir 191modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 192 193### 194# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 195# Usage: 196# $(Q)$(MAKE) $(dtbinst)=dir 197dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj 198 199### 200# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 201# Usage: 202# $(Q)$(MAKE) $(clean)=dir 203clean := -f $(srctree)/scripts/Makefile.clean obj 204 205### 206# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 207# Usage: 208# $(Q)$(MAKE) $(hdr-inst)=dir 209hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 210 211# Prefix -I with $(srctree) if it is not an absolute path. 212# skip if -I has no parameter 213addtree = $(if $(patsubst -I%,%,$(1)), \ 214$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1)) 215 216# Find all -I options and call addtree 217flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 218 219# echo command. 220# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 221echo-cmd = $(if $($(quiet)cmd_$(1)),\ 222 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 223 224# printing commands 225cmd = @$(echo-cmd) $(cmd_$(1)) 226 227# Add $(obj)/ for paths that are not absolute 228objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 229 230### 231# if_changed - execute command if any prerequisite is newer than 232# target, or command line has changed 233# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 234# including used config symbols 235# if_changed_rule - as if_changed but execute rule instead 236# See Documentation/kbuild/makefiles.txt for more info 237 238ifneq ($(KBUILD_NOCMDDEP),1) 239# Check if both arguments are the same including their order. Result is empty 240# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 241arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 242 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 243else 244arg-check = $(if $(strip $(cmd_$@)),,1) 245endif 246 247# Replace >$< with >$$< to preserve $ when reloading the .cmd file 248# (needed for make) 249# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file 250# (needed for make) 251# Replace >'< with >'\''< to be able to enclose the whole string in '...' 252# (needed for the shell) 253make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) 254 255# Find any prerequisites that is newer than target or that does not exist. 256# PHONY targets skipped in both cases. 257any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 258 259# Execute command if command has changed or prerequisite(s) are updated. 260if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 261 @set -e; \ 262 $(echo-cmd) $(cmd_$(1)); \ 263 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 264 265# Execute the command and also postprocess generated .d dependencies file. 266if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ 267 @set -e; \ 268 $(cmd_and_fixdep), @:) 269 270ifndef CONFIG_TRIM_UNUSED_KSYMS 271 272cmd_and_fixdep = \ 273 $(echo-cmd) $(cmd_$(1)); \ 274 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ 275 rm -f $(depfile); \ 276 mv -f $(dot-target).tmp $(dot-target).cmd; 277 278else 279 280# Filter out exported kernel symbol names from the preprocessor output. 281# See also __KSYM_DEPS__ in include/linux/export.h. 282# We disable the depfile generation here, so as not to overwrite the existing 283# depfile while fixdep is parsing it. 284flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1))) 285ksym_dep_filter = \ 286 case "$(1)" in \ 287 cc_*_c|cpp_i_c) \ 288 $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \ 289 as_*_S|cpp_s_S) \ 290 $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \ 291 boot*|build*|cpp_its_S|*cpp_lds_S|dtc|host*|vdso*) : ;; \ 292 *) echo "Don't know how to preprocess $(1)" >&2; false ;; \ 293 esac | tr ";" "\n" | sed -n 's/^.*=== __KSYM_\(.*\) ===.*$$/_\1/p' 294 295cmd_and_fixdep = \ 296 $(echo-cmd) $(cmd_$(1)); \ 297 $(ksym_dep_filter) | \ 298 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \ 299 > $(dot-target).tmp; \ 300 rm -f $(depfile); \ 301 mv -f $(dot-target).tmp $(dot-target).cmd; 302 303endif 304 305# Usage: $(call if_changed_rule,foo) 306# Will check if $(cmd_foo) or any of the prerequisites changed, 307# and if so will execute $(rule_foo). 308if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \ 309 @set -e; \ 310 $(rule_$(1)), @:) 311 312### 313# why - tell why a target got built 314# enabled by make V=2 315# Output (listed in the order they are checked): 316# (1) - due to target is PHONY 317# (2) - due to target missing 318# (3) - due to: file1.h file2.h 319# (4) - due to command line change 320# (5) - due to missing .cmd file 321# (6) - due to target not in $(targets) 322# (1) PHONY targets are always build 323# (2) No target, so we better build it 324# (3) Prerequisite is newer than target 325# (4) The command line stored in the file named dir/.target.cmd 326# differed from actual command line. This happens when compiler 327# options changes 328# (5) No dir/.target.cmd file (used to store command line) 329# (6) No dir/.target.cmd file and target not listed in $(targets) 330# This is a good hint that there is a bug in the kbuild file 331ifeq ($(KBUILD_VERBOSE),2) 332why = \ 333 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 334 $(if $(wildcard $@), \ 335 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 336 $(if $(arg-check), \ 337 $(if $(cmd_$@),- due to command line change, \ 338 $(if $(filter $@, $(targets)), \ 339 - due to missing .cmd file, \ 340 - due to $(notdir $@) not in $$(targets) \ 341 ) \ 342 ) \ 343 ) \ 344 ), \ 345 - due to target missing \ 346 ) \ 347 ) 348 349echo-why = $(call escsq, $(strip $(why))) 350endif 351 352############################################################################### 353# 354# When a Kconfig string contains a filename, it is suitable for 355# passing to shell commands. It is surrounded by double-quotes, and 356# any double-quotes or backslashes within it are escaped by 357# backslashes. 358# 359# This is no use for dependencies or $(wildcard). We need to strip the 360# surrounding quotes and the escaping from quotes and backslashes, and 361# we *do* need to escape any spaces in the string. So, for example: 362# 363# Usage: $(eval $(call config_filename,FOO)) 364# 365# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 366# transformed as described above to be suitable for use within the 367# makefile. 368# 369# Also, if the filename is a relative filename and exists in the source 370# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 371# be prefixed to *both* command invocation and dependencies. 372# 373# Note: We also print the filenames in the quiet_cmd_foo text, and 374# perhaps ought to have a version specially escaped for that purpose. 375# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 376# enough. It'll strip the quotes in the common case where there's no 377# space and it's a simple filename, and it'll retain the quotes when 378# there's a space. There are some esoteric cases in which it'll print 379# the wrong thing, but we don't really care. The actual dependencies 380# and commands *do* get it right, with various combinations of single 381# and double quotes, backslashes and spaces in the filenames. 382# 383############################################################################### 384# 385define config_filename 386ifneq ($$(CONFIG_$(1)),"") 387$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 388ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 389else 390ifeq ($$(wildcard $$($(1)_FILENAME)),) 391ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 392$(1)_SRCPREFIX := $(srctree)/ 393endif 394endif 395endif 396endif 397endef 398# 399############################################################################### 400 401# delete partially updated (i.e. corrupted) files on error 402.DELETE_ON_ERROR: 403