1# SPDX-License-Identifier: GPL-2.0 2#### 3# kbuild: Generic definitions 4 5# Convenient variables 6comma := , 7quote := " 8squote := ' 9empty := 10space := $(empty) $(empty) 11space_escape := _-_SPACE_-_ 12pound := \# 13 14### 15# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o 16dot-target = $(dir $@).$(notdir $@) 17 18### 19# The temporary file to save gcc -MD generated dependencies must not 20# contain a comma 21depfile = $(subst $(comma),_,$(dot-target).d) 22 23### 24# filename of target with directory and extension stripped 25basetarget = $(basename $(notdir $@)) 26 27### 28# real prerequisites without phony targets 29real-prereqs = $(filter-out $(PHONY), $^) 30 31### 32# Escape single quote for use in echo statements 33escsq = $(subst $(squote),'\$(squote)',$1) 34 35### 36# Easy method for doing a status message 37 kecho := : 38 quiet_kecho := echo 39silent_kecho := : 40kecho := $($(quiet)kecho) 41 42### 43# filechk is used to check if the content of a generated file is updated. 44# Sample usage: 45# 46# filechk_sample = echo $(KERNELRELEASE) 47# version.h: FORCE 48# $(call filechk,sample) 49# 50# The rule defined shall write to stdout the content of the new file. 51# The existing file will be compared with the new one. 52# - If no file exist it is created 53# - If the content differ the new file is used 54# - If they are equal no change, and no timestamp update 55# - stdin is piped in from the first prerequisite ($<) so one has 56# to specify a valid file as first prerequisite (often the kbuild file) 57define filechk 58 $(Q)set -e; \ 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>gcc is found in PATH. 76# If no gcc found in PATH with listed prefixes return nothing 77cc-cross-prefix = $(firstword $(foreach c, $(filter-out -%, $(1)), \ 78 $(if $(shell which $(c)gcc), $(c)))) 79 80# output directory for tests below 81TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/) 82 83# try-run 84# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) 85# Exit code chooses option. "$$TMP" serves as a temporary file and is 86# automatically cleaned up. 87try-run = $(shell set -e; \ 88 TMP="$(TMPOUT).$$$$.tmp"; \ 89 TMPO="$(TMPOUT).$$$$.o"; \ 90 if ($(1)) >/dev/null 2>&1; \ 91 then echo "$(2)"; \ 92 else echo "$(3)"; \ 93 fi; \ 94 rm -f "$$TMP" "$$TMPO") 95 96# as-option 97# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) 98 99as-option = $(call try-run,\ 100 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2)) 101 102# as-instr 103# Usage: cflags-y += $(call as-instr,instr,option1,option2) 104 105as-instr = $(call try-run,\ 106 printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) 107 108# __cc-option 109# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) 110__cc-option = $(call try-run,\ 111 $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4)) 112 113# Do not attempt to build with gcc plugins during cc-option tests. 114# (And this uses delayed resolution so the flags will be up to date.) 115CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) 116 117# cc-option 118# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) 119 120cc-option = $(call __cc-option, $(CC),\ 121 $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2)) 122 123# hostcc-option 124# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) 125hostcc-option = $(call __cc-option, $(HOSTCC),\ 126 $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) 127 128# cc-option-yn 129# Usage: flag := $(call cc-option-yn,-march=winchip-c6) 130cc-option-yn = $(call try-run,\ 131 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) 132 133# cc-disable-warning 134# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) 135cc-disable-warning = $(call try-run,\ 136 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) 137 138# cc-ifversion 139# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) 140cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4)) 141 142# ld-option 143# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y) 144ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3)) 145 146# ar-option 147# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 148# Important: no spaces around options 149ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 150 151# ld-version 152# Note this is mainly for HJ Lu's 3 number binutil versions 153ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 154 155# ld-ifversion 156# Usage: $(call ld-ifversion, -ge, 22252, y) 157ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 158 159###### 160 161### 162# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 163# Usage: 164# $(Q)$(MAKE) $(build)=dir 165build := -f $(srctree)/scripts/Makefile.build obj 166 167### 168# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 169# Usage: 170# $(Q)$(MAKE) $(modbuiltin)=dir 171modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 172 173### 174# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 175# Usage: 176# $(Q)$(MAKE) $(dtbinst)=dir 177dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj 178 179### 180# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 181# Usage: 182# $(Q)$(MAKE) $(clean)=dir 183clean := -f $(srctree)/scripts/Makefile.clean obj 184 185### 186# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 187# Usage: 188# $(Q)$(MAKE) $(hdr-inst)=dir 189hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 190 191# echo command. 192# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 193echo-cmd = $(if $($(quiet)cmd_$(1)),\ 194 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 195 196# printing commands 197cmd = @set -e; $(echo-cmd) $(cmd_$(1)) 198 199# Add $(obj)/ for paths that are not absolute 200objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 201 202### 203# if_changed - execute command if any prerequisite is newer than 204# target, or command line has changed 205# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 206# including used config symbols 207# if_changed_rule - as if_changed but execute rule instead 208# See Documentation/kbuild/makefiles.txt for more info 209 210ifneq ($(KBUILD_NOCMDDEP),1) 211# Check if both arguments are the same including their order. Result is empty 212# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 213arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 214 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 215else 216arg-check = $(if $(strip $(cmd_$@)),,1) 217endif 218 219# Replace >$< with >$$< to preserve $ when reloading the .cmd file 220# (needed for make) 221# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file 222# (needed for make) 223# Replace >'< with >'\''< to be able to enclose the whole string in '...' 224# (needed for the shell) 225make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) 226 227# Find any prerequisites that is newer than target or that does not exist. 228# PHONY targets skipped in both cases. 229any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 230 231# Execute command if command has changed or prerequisite(s) are updated. 232if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 233 $(cmd); \ 234 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 235 236# Execute the command and also postprocess generated .d dependencies file. 237if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),$(cmd_and_fixdep),@:) 238 239cmd_and_fixdep = \ 240 $(cmd); \ 241 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\ 242 rm -f $(depfile) 243 244# Usage: $(call if_changed_rule,foo) 245# Will check if $(cmd_foo) or any of the prerequisites changed, 246# and if so will execute $(rule_foo). 247if_changed_rule = $(if $(strip $(any-prereq) $(arg-check)),$(rule_$(1)),@:) 248 249### 250# why - tell why a target got built 251# enabled by make V=2 252# Output (listed in the order they are checked): 253# (1) - due to target is PHONY 254# (2) - due to target missing 255# (3) - due to: file1.h file2.h 256# (4) - due to command line change 257# (5) - due to missing .cmd file 258# (6) - due to target not in $(targets) 259# (1) PHONY targets are always build 260# (2) No target, so we better build it 261# (3) Prerequisite is newer than target 262# (4) The command line stored in the file named dir/.target.cmd 263# differed from actual command line. This happens when compiler 264# options changes 265# (5) No dir/.target.cmd file (used to store command line) 266# (6) No dir/.target.cmd file and target not listed in $(targets) 267# This is a good hint that there is a bug in the kbuild file 268ifeq ($(KBUILD_VERBOSE),2) 269why = \ 270 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 271 $(if $(wildcard $@), \ 272 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 273 $(if $(arg-check), \ 274 $(if $(cmd_$@),- due to command line change, \ 275 $(if $(filter $@, $(targets)), \ 276 - due to missing .cmd file, \ 277 - due to $(notdir $@) not in $$(targets) \ 278 ) \ 279 ) \ 280 ) \ 281 ), \ 282 - due to target missing \ 283 ) \ 284 ) 285 286echo-why = $(call escsq, $(strip $(why))) 287endif 288 289############################################################################### 290# 291# When a Kconfig string contains a filename, it is suitable for 292# passing to shell commands. It is surrounded by double-quotes, and 293# any double-quotes or backslashes within it are escaped by 294# backslashes. 295# 296# This is no use for dependencies or $(wildcard). We need to strip the 297# surrounding quotes and the escaping from quotes and backslashes, and 298# we *do* need to escape any spaces in the string. So, for example: 299# 300# Usage: $(eval $(call config_filename,FOO)) 301# 302# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 303# transformed as described above to be suitable for use within the 304# makefile. 305# 306# Also, if the filename is a relative filename and exists in the source 307# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 308# be prefixed to *both* command invocation and dependencies. 309# 310# Note: We also print the filenames in the quiet_cmd_foo text, and 311# perhaps ought to have a version specially escaped for that purpose. 312# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 313# enough. It'll strip the quotes in the common case where there's no 314# space and it's a simple filename, and it'll retain the quotes when 315# there's a space. There are some esoteric cases in which it'll print 316# the wrong thing, but we don't really care. The actual dependencies 317# and commands *do* get it right, with various combinations of single 318# and double quotes, backslashes and spaces in the filenames. 319# 320############################################################################### 321# 322define config_filename 323ifneq ($$(CONFIG_$(1)),"") 324$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 325ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 326else 327ifeq ($$(wildcard $$($(1)_FILENAME)),) 328ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 329$(1)_SRCPREFIX := $(srctree)/ 330endif 331endif 332endif 333endif 334endef 335# 336############################################################################### 337 338# delete partially updated (i.e. corrupted) files on error 339.DELETE_ON_ERROR: 340 341# do not delete intermediate files automatically 342.SECONDARY: 343