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))/) 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).$$$$.tmp"; \ 92 TMPO="$(TMPOUT).$$$$.o"; \ 93 if ($(1)) >/dev/null 2>&1; \ 94 then echo "$(2)"; \ 95 else echo "$(3)"; \ 96 fi; \ 97 rm -f "$$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.) 118# In addition, do not include the asm macros which are built later. 119CC_OPTION_FILTERED = $(GCC_PLUGINS_CFLAGS) $(ASM_MACRO_FLAGS) 120CC_OPTION_CFLAGS = $(filter-out $(CC_OPTION_FILTERED),$(KBUILD_CFLAGS)) 121 122# cc-option 123# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) 124 125cc-option = $(call __cc-option, $(CC),\ 126 $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2)) 127 128# hostcc-option 129# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) 130hostcc-option = $(call __cc-option, $(HOSTCC),\ 131 $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) 132 133# cc-option-yn 134# Usage: flag := $(call cc-option-yn,-march=winchip-c6) 135cc-option-yn = $(call try-run,\ 136 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) 137 138# cc-disable-warning 139# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) 140cc-disable-warning = $(call try-run,\ 141 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) 142 143# cc-name 144# Expands to either gcc or clang 145cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc) 146 147# cc-version 148cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) 149 150# cc-fullversion 151cc-fullversion = $(shell $(CONFIG_SHELL) \ 152 $(srctree)/scripts/gcc-version.sh -p $(CC)) 153 154# cc-ifversion 155# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) 156cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4)) 157 158# cc-ldoption 159# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 160cc-ldoption = $(call try-run,\ 161 $(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 162 163# ld-option 164# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y) 165ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3)) 166 167# ar-option 168# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 169# Important: no spaces around options 170ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 171 172# ld-version 173# Note this is mainly for HJ Lu's 3 number binutil versions 174ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 175 176# ld-ifversion 177# Usage: $(call ld-ifversion, -ge, 22252, y) 178ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 179 180###### 181 182### 183# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 184# Usage: 185# $(Q)$(MAKE) $(build)=dir 186build := -f $(srctree)/scripts/Makefile.build obj 187 188### 189# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 190# Usage: 191# $(Q)$(MAKE) $(modbuiltin)=dir 192modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 193 194### 195# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 196# Usage: 197# $(Q)$(MAKE) $(dtbinst)=dir 198dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj 199 200### 201# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 202# Usage: 203# $(Q)$(MAKE) $(clean)=dir 204clean := -f $(srctree)/scripts/Makefile.clean obj 205 206### 207# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 208# Usage: 209# $(Q)$(MAKE) $(hdr-inst)=dir 210hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 211 212# Prefix -I with $(srctree) if it is not an absolute path. 213# skip if -I has no parameter 214addtree = $(if $(patsubst -I%,%,$(1)), \ 215$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1)) 216 217# Find all -I options and call addtree 218flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 219 220# echo command. 221# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 222echo-cmd = $(if $($(quiet)cmd_$(1)),\ 223 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 224 225# printing commands 226cmd = @$(echo-cmd) $(cmd_$(1)) 227 228# Add $(obj)/ for paths that are not absolute 229objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 230 231### 232# if_changed - execute command if any prerequisite is newer than 233# target, or command line has changed 234# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 235# including used config symbols 236# if_changed_rule - as if_changed but execute rule instead 237# See Documentation/kbuild/makefiles.txt for more info 238 239ifneq ($(KBUILD_NOCMDDEP),1) 240# Check if both arguments are the same including their order. Result is empty 241# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 242arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 243 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 244else 245arg-check = $(if $(strip $(cmd_$@)),,1) 246endif 247 248# Replace >$< with >$$< to preserve $ when reloading the .cmd file 249# (needed for make) 250# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file 251# (needed for make) 252# Replace >'< with >'\''< to be able to enclose the whole string in '...' 253# (needed for the shell) 254make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) 255 256# Find any prerequisites that is newer than target or that does not exist. 257# PHONY targets skipped in both cases. 258any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 259 260# Execute command if command has changed or prerequisite(s) are updated. 261if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 262 @set -e; \ 263 $(echo-cmd) $(cmd_$(1)); \ 264 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 265 266# Execute the command and also postprocess generated .d dependencies file. 267if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ 268 @set -e; \ 269 $(cmd_and_fixdep), @:) 270 271ifndef CONFIG_TRIM_UNUSED_KSYMS 272 273cmd_and_fixdep = \ 274 $(echo-cmd) $(cmd_$(1)); \ 275 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ 276 rm -f $(depfile); \ 277 mv -f $(dot-target).tmp $(dot-target).cmd; 278 279else 280 281# Filter out exported kernel symbol names from the preprocessor output. 282# See also __KSYM_DEPS__ in include/linux/export.h. 283# We disable the depfile generation here, so as not to overwrite the existing 284# depfile while fixdep is parsing it. 285flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1))) 286ksym_dep_filter = \ 287 case "$(1)" in \ 288 cc_*_c|cpp_i_c) \ 289 $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \ 290 as_*_S|cpp_s_S) \ 291 $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \ 292 boot*|build*|cpp_its_S|*cpp_lds_S|dtc|host*|vdso*) : ;; \ 293 *) echo "Don't know how to preprocess $(1)" >&2; false ;; \ 294 esac | tr ";" "\n" | sed -n 's/^.*=== __KSYM_\(.*\) ===.*$$/_\1/p' 295 296cmd_and_fixdep = \ 297 $(echo-cmd) $(cmd_$(1)); \ 298 $(ksym_dep_filter) | \ 299 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \ 300 > $(dot-target).tmp; \ 301 rm -f $(depfile); \ 302 mv -f $(dot-target).tmp $(dot-target).cmd; 303 304endif 305 306# Usage: $(call if_changed_rule,foo) 307# Will check if $(cmd_foo) or any of the prerequisites changed, 308# and if so will execute $(rule_foo). 309if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \ 310 @set -e; \ 311 $(rule_$(1)), @:) 312 313### 314# why - tell why a target got built 315# enabled by make V=2 316# Output (listed in the order they are checked): 317# (1) - due to target is PHONY 318# (2) - due to target missing 319# (3) - due to: file1.h file2.h 320# (4) - due to command line change 321# (5) - due to missing .cmd file 322# (6) - due to target not in $(targets) 323# (1) PHONY targets are always build 324# (2) No target, so we better build it 325# (3) Prerequisite is newer than target 326# (4) The command line stored in the file named dir/.target.cmd 327# differed from actual command line. This happens when compiler 328# options changes 329# (5) No dir/.target.cmd file (used to store command line) 330# (6) No dir/.target.cmd file and target not listed in $(targets) 331# This is a good hint that there is a bug in the kbuild file 332ifeq ($(KBUILD_VERBOSE),2) 333why = \ 334 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 335 $(if $(wildcard $@), \ 336 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 337 $(if $(arg-check), \ 338 $(if $(cmd_$@),- due to command line change, \ 339 $(if $(filter $@, $(targets)), \ 340 - due to missing .cmd file, \ 341 - due to $(notdir $@) not in $$(targets) \ 342 ) \ 343 ) \ 344 ) \ 345 ), \ 346 - due to target missing \ 347 ) \ 348 ) 349 350echo-why = $(call escsq, $(strip $(why))) 351endif 352 353############################################################################### 354# 355# When a Kconfig string contains a filename, it is suitable for 356# passing to shell commands. It is surrounded by double-quotes, and 357# any double-quotes or backslashes within it are escaped by 358# backslashes. 359# 360# This is no use for dependencies or $(wildcard). We need to strip the 361# surrounding quotes and the escaping from quotes and backslashes, and 362# we *do* need to escape any spaces in the string. So, for example: 363# 364# Usage: $(eval $(call config_filename,FOO)) 365# 366# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 367# transformed as described above to be suitable for use within the 368# makefile. 369# 370# Also, if the filename is a relative filename and exists in the source 371# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 372# be prefixed to *both* command invocation and dependencies. 373# 374# Note: We also print the filenames in the quiet_cmd_foo text, and 375# perhaps ought to have a version specially escaped for that purpose. 376# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 377# enough. It'll strip the quotes in the common case where there's no 378# space and it's a simple filename, and it'll retain the quotes when 379# there's a space. There are some esoteric cases in which it'll print 380# the wrong thing, but we don't really care. The actual dependencies 381# and commands *do* get it right, with various combinations of single 382# and double quotes, backslashes and spaces in the filenames. 383# 384############################################################################### 385# 386define config_filename 387ifneq ($$(CONFIG_$(1)),"") 388$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 389ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 390else 391ifeq ($$(wildcard $$($(1)_FILENAME)),) 392ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 393$(1)_SRCPREFIX := $(srctree)/ 394endif 395endif 396endif 397endif 398endef 399# 400############################################################################### 401 402# delete partially updated (i.e. corrupted) files on error 403.DELETE_ON_ERROR: 404