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# real prerequisites without phony targets 28real-prereqs = $(filter-out $(PHONY), $^) 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# 45# filechk_sample = echo $(KERNELRELEASE) 46# version.h: FORCE 47# $(call filechk,sample) 48# 49# The rule defined shall write to stdout the content of the new file. 50# The existing file will be compared with the new one. 51# - If no file exist it is created 52# - If the content differ the new file is used 53# - If they are equal no change, and no timestamp update 54# - stdin is piped in from the first prerequisite ($<) 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>gcc is found in PATH. 75# If no gcc found in PATH with listed prefixes return nothing 76cc-cross-prefix = $(firstword $(foreach c, $(filter-out -%, $(1)), \ 77 $(if $(shell which $(c)gcc), $(c)))) 78 79# output directory for tests below 80TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/) 81 82# try-run 83# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) 84# Exit code chooses option. "$$TMP" serves as a temporary file and is 85# automatically cleaned up. 86try-run = $(shell set -e; \ 87 TMP="$(TMPOUT).$$$$.tmp"; \ 88 TMPO="$(TMPOUT).$$$$.o"; \ 89 if ($(1)) >/dev/null 2>&1; \ 90 then echo "$(2)"; \ 91 else echo "$(3)"; \ 92 fi; \ 93 rm -f "$$TMP" "$$TMPO") 94 95# as-option 96# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) 97 98as-option = $(call try-run,\ 99 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2)) 100 101# as-instr 102# Usage: cflags-y += $(call as-instr,instr,option1,option2) 103 104as-instr = $(call try-run,\ 105 printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) 106 107# __cc-option 108# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) 109__cc-option = $(call try-run,\ 110 $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4)) 111 112# Do not attempt to build with gcc plugins during cc-option tests. 113# (And this uses delayed resolution so the flags will be up to date.) 114CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) 115 116# cc-option 117# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) 118 119cc-option = $(call __cc-option, $(CC),\ 120 $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2)) 121 122# hostcc-option 123# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) 124hostcc-option = $(call __cc-option, $(HOSTCC),\ 125 $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) 126 127# cc-option-yn 128# Usage: flag := $(call cc-option-yn,-march=winchip-c6) 129cc-option-yn = $(call try-run,\ 130 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) 131 132# cc-disable-warning 133# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) 134cc-disable-warning = $(call try-run,\ 135 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) 136 137# cc-ifversion 138# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) 139cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4)) 140 141# cc-ldoption 142# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 143cc-ldoption = $(call try-run,\ 144 $(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 145 146# ld-option 147# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y) 148ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3)) 149 150# ar-option 151# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 152# Important: no spaces around options 153ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 154 155# ld-version 156# Note this is mainly for HJ Lu's 3 number binutil versions 157ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 158 159# ld-ifversion 160# Usage: $(call ld-ifversion, -ge, 22252, y) 161ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 162 163###### 164 165### 166# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 167# Usage: 168# $(Q)$(MAKE) $(build)=dir 169build := -f $(srctree)/scripts/Makefile.build obj 170 171### 172# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 173# Usage: 174# $(Q)$(MAKE) $(modbuiltin)=dir 175modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 176 177### 178# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 179# Usage: 180# $(Q)$(MAKE) $(dtbinst)=dir 181dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj 182 183### 184# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 185# Usage: 186# $(Q)$(MAKE) $(clean)=dir 187clean := -f $(srctree)/scripts/Makefile.clean obj 188 189### 190# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 191# Usage: 192# $(Q)$(MAKE) $(hdr-inst)=dir 193hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 194 195# Prefix -I with $(srctree) if it is not an absolute path. 196# skip if -I has no parameter 197addtree = $(if $(patsubst -I%,%,$(1)), \ 198$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1)) 199 200# Find all -I options and call addtree 201flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 202 203# echo command. 204# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 205echo-cmd = $(if $($(quiet)cmd_$(1)),\ 206 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 207 208# printing commands 209cmd = @set -e; $(echo-cmd) $(cmd_$(1)) 210 211# Add $(obj)/ for paths that are not absolute 212objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 213 214### 215# if_changed - execute command if any prerequisite is newer than 216# target, or command line has changed 217# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 218# including used config symbols 219# if_changed_rule - as if_changed but execute rule instead 220# See Documentation/kbuild/makefiles.txt for more info 221 222ifneq ($(KBUILD_NOCMDDEP),1) 223# Check if both arguments are the same including their order. Result is empty 224# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 225arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 226 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 227else 228arg-check = $(if $(strip $(cmd_$@)),,1) 229endif 230 231# Replace >$< with >$$< to preserve $ when reloading the .cmd file 232# (needed for make) 233# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file 234# (needed for make) 235# Replace >'< with >'\''< to be able to enclose the whole string in '...' 236# (needed for the shell) 237make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) 238 239# Find any prerequisites that is newer than target or that does not exist. 240# PHONY targets skipped in both cases. 241any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 242 243# Execute command if command has changed or prerequisite(s) are updated. 244if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 245 $(cmd); \ 246 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 247 248# Execute the command and also postprocess generated .d dependencies file. 249if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),$(cmd_and_fixdep),@:) 250 251cmd_and_fixdep = \ 252 $(cmd); \ 253 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\ 254 rm -f $(depfile) 255 256# Usage: $(call if_changed_rule,foo) 257# Will check if $(cmd_foo) or any of the prerequisites changed, 258# and if so will execute $(rule_foo). 259if_changed_rule = $(if $(strip $(any-prereq) $(arg-check)),$(rule_$(1)),@:) 260 261### 262# why - tell why a target got built 263# enabled by make V=2 264# Output (listed in the order they are checked): 265# (1) - due to target is PHONY 266# (2) - due to target missing 267# (3) - due to: file1.h file2.h 268# (4) - due to command line change 269# (5) - due to missing .cmd file 270# (6) - due to target not in $(targets) 271# (1) PHONY targets are always build 272# (2) No target, so we better build it 273# (3) Prerequisite is newer than target 274# (4) The command line stored in the file named dir/.target.cmd 275# differed from actual command line. This happens when compiler 276# options changes 277# (5) No dir/.target.cmd file (used to store command line) 278# (6) No dir/.target.cmd file and target not listed in $(targets) 279# This is a good hint that there is a bug in the kbuild file 280ifeq ($(KBUILD_VERBOSE),2) 281why = \ 282 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 283 $(if $(wildcard $@), \ 284 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 285 $(if $(arg-check), \ 286 $(if $(cmd_$@),- due to command line change, \ 287 $(if $(filter $@, $(targets)), \ 288 - due to missing .cmd file, \ 289 - due to $(notdir $@) not in $$(targets) \ 290 ) \ 291 ) \ 292 ) \ 293 ), \ 294 - due to target missing \ 295 ) \ 296 ) 297 298echo-why = $(call escsq, $(strip $(why))) 299endif 300 301############################################################################### 302# 303# When a Kconfig string contains a filename, it is suitable for 304# passing to shell commands. It is surrounded by double-quotes, and 305# any double-quotes or backslashes within it are escaped by 306# backslashes. 307# 308# This is no use for dependencies or $(wildcard). We need to strip the 309# surrounding quotes and the escaping from quotes and backslashes, and 310# we *do* need to escape any spaces in the string. So, for example: 311# 312# Usage: $(eval $(call config_filename,FOO)) 313# 314# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 315# transformed as described above to be suitable for use within the 316# makefile. 317# 318# Also, if the filename is a relative filename and exists in the source 319# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 320# be prefixed to *both* command invocation and dependencies. 321# 322# Note: We also print the filenames in the quiet_cmd_foo text, and 323# perhaps ought to have a version specially escaped for that purpose. 324# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 325# enough. It'll strip the quotes in the common case where there's no 326# space and it's a simple filename, and it'll retain the quotes when 327# there's a space. There are some esoteric cases in which it'll print 328# the wrong thing, but we don't really care. The actual dependencies 329# and commands *do* get it right, with various combinations of single 330# and double quotes, backslashes and spaces in the filenames. 331# 332############################################################################### 333# 334define config_filename 335ifneq ($$(CONFIG_$(1)),"") 336$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 337ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 338else 339ifeq ($$(wildcard $$($(1)_FILENAME)),) 340ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 341$(1)_SRCPREFIX := $(srctree)/ 342endif 343endif 344endif 345endif 346endef 347# 348############################################################################### 349 350# delete partially updated (i.e. corrupted) files on error 351.DELETE_ON_ERROR: 352 353# do not delete intermediate files automatically 354.SECONDARY: 355