1#### 2# kbuild: Generic definitions 3 4# Convenient variables 5comma := , 6quote := " 7squote := ' 8empty := 9space := $(empty) $(empty) 10pound := \# 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))/).tmp_$$$$ 85 86# try-run 87# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) 88# Exit code chooses option. "$$TMP" is can be used as temporary file and 89# is automatically cleaned up. 90try-run = $(shell set -e; \ 91 TMP=$(TMPOUT)/tmp; \ 92 TMPO=$(TMPOUT)/tmp.o; \ 93 mkdir -p $(TMPOUT); \ 94 trap "rm -rf $(TMPOUT)" EXIT; \ 95 if ($(1)) >/dev/null 2>&1; \ 96 then echo "$(2)"; \ 97 else echo "$(3)"; \ 98 fi) 99 100# as-option 101# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) 102 103as-option = $(call try-run,\ 104 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$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) $(KBUILD_CFLAGS),$(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 $(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) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) 136 137# cc-option-align 138# Prefix align with either -falign or -malign 139cc-option-align = $(subst -functions=0,,\ 140 $(call cc-option,-falign-functions=0,-malign-functions=0)) 141 142# cc-disable-warning 143# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) 144cc-disable-warning = $(call try-run,\ 145 $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) 146 147# cc-name 148# Expands to either gcc or clang 149cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc) 150 151# cc-version 152cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) 153 154# cc-fullversion 155cc-fullversion = $(shell $(CONFIG_SHELL) \ 156 $(srctree)/scripts/gcc-version.sh -p $(CC)) 157 158# cc-ifversion 159# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) 160cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4)) 161 162# cc-ldoption 163# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 164cc-ldoption = $(call try-run,\ 165 $(CC) $(1) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 166 167# ld-option 168# Usage: LDFLAGS += $(call ld-option, -X) 169ld-option = $(call try-run, $(LD) $(LDFLAGS) $(1) -v,$(1),$(2)) 170 171# ar-option 172# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 173# Important: no spaces around options 174ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 175 176# ld-version 177# Note this is mainly for HJ Lu's 3 number binutil versions 178ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 179 180# ld-ifversion 181# Usage: $(call ld-ifversion, -ge, 22252, y) 182ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 183 184###### 185 186### 187# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 188# Usage: 189# $(Q)$(MAKE) $(build)=dir 190build := -f $(srctree)/scripts/Makefile.build obj 191 192### 193# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 194# Usage: 195# $(Q)$(MAKE) $(modbuiltin)=dir 196modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 197 198### 199# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 200# Usage: 201# $(Q)$(MAKE) $(dtbinst)=dir 202dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj 203 204### 205# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 206# Usage: 207# $(Q)$(MAKE) $(clean)=dir 208clean := -f $(srctree)/scripts/Makefile.clean obj 209 210### 211# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 212# Usage: 213# $(Q)$(MAKE) $(hdr-inst)=dir 214hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 215 216# Prefix -I with $(srctree) if it is not an absolute path. 217# skip if -I has no parameter 218addtree = $(if $(patsubst -I%,%,$(1)), \ 219$(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1)) 220 221# Find all -I options and call addtree 222flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 223 224# echo command. 225# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 226echo-cmd = $(if $($(quiet)cmd_$(1)),\ 227 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 228 229# printing commands 230cmd = @$(echo-cmd) $(cmd_$(1)) 231 232# Add $(obj)/ for paths that are not absolute 233objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 234 235### 236# if_changed - execute command if any prerequisite is newer than 237# target, or command line has changed 238# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 239# including used config symbols 240# if_changed_rule - as if_changed but execute rule instead 241# See Documentation/kbuild/makefiles.txt for more info 242 243ifneq ($(KBUILD_NOCMDDEP),1) 244# Check if both arguments has same arguments. Result is empty string if equal. 245# User may override this check using make KBUILD_NOCMDDEP=1 246arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \ 247 $(filter-out $(cmd_$@), $(cmd_$(1))) ) 248else 249arg-check = $(if $(strip $(cmd_$@)),,1) 250endif 251 252# Replace >$< with >$$< to preserve $ when reloading the .cmd file 253# (needed for make) 254# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file 255# (needed for make) 256# Replace >'< with >'\''< to be able to enclose the whole string in '...' 257# (needed for the shell) 258make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) 259 260# Find any prerequisites that is newer than target or that does not exist. 261# PHONY targets skipped in both cases. 262any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 263 264# Execute command if command has changed or prerequisite(s) are updated. 265# 266if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 267 @set -e; \ 268 $(echo-cmd) $(cmd_$(1)); \ 269 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd) 270 271# Execute the command and also postprocess generated .d dependencies file. 272if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ 273 @set -e; \ 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) 278 279# Usage: $(call if_changed_rule,foo) 280# Will check if $(cmd_foo) or any of the prerequisites changed, 281# and if so will execute $(rule_foo). 282if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \ 283 @set -e; \ 284 $(rule_$(1))) 285 286### 287# why - tell why a a target got build 288# enabled by make V=2 289# Output (listed in the order they are checked): 290# (1) - due to target is PHONY 291# (2) - due to target missing 292# (3) - due to: file1.h file2.h 293# (4) - due to command line change 294# (5) - due to missing .cmd file 295# (6) - due to target not in $(targets) 296# (1) PHONY targets are always build 297# (2) No target, so we better build it 298# (3) Prerequisite is newer than target 299# (4) The command line stored in the file named dir/.target.cmd 300# differed from actual command line. This happens when compiler 301# options changes 302# (5) No dir/.target.cmd file (used to store command line) 303# (6) No dir/.target.cmd file and target not listed in $(targets) 304# This is a good hint that there is a bug in the kbuild file 305ifeq ($(KBUILD_VERBOSE),2) 306why = \ 307 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 308 $(if $(wildcard $@), \ 309 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 310 $(if $(arg-check), \ 311 $(if $(cmd_$@),- due to command line change, \ 312 $(if $(filter $@, $(targets)), \ 313 - due to missing .cmd file, \ 314 - due to $(notdir $@) not in $$(targets) \ 315 ) \ 316 ) \ 317 ) \ 318 ), \ 319 - due to target missing \ 320 ) \ 321 ) 322 323echo-why = $(call escsq, $(strip $(why))) 324endif 325 326############################################################################### 327# 328# When a Kconfig string contains a filename, it is suitable for 329# passing to shell commands. It is surrounded by double-quotes, and 330# any double-quotes or backslashes within it are escaped by 331# backslashes. 332# 333# This is no use for dependencies or $(wildcard). We need to strip the 334# surrounding quotes and the escaping from quotes and backslashes, and 335# we *do* need to escape any spaces in the string. So, for example: 336# 337# Usage: $(eval $(call config_filename,FOO)) 338# 339# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 340# transformed as described above to be suitable for use within the 341# makefile. 342# 343# Also, if the filename is a relative filename and exists in the source 344# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 345# be prefixed to *both* command invocation and dependencies. 346# 347# Note: We also print the filenames in the quiet_cmd_foo text, and 348# perhaps ought to have a version specially escaped for that purpose. 349# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 350# enough. It'll strip the quotes in the common case where there's no 351# space and it's a simple filename, and it'll retain the quotes when 352# there's a space. There are some esoteric cases in which it'll print 353# the wrong thing, but we don't really care. The actual dependencies 354# and commands *do* get it right, with various combinations of single 355# and double quotes, backslashes and spaces in the filenames. 356# 357############################################################################### 358# 359space_escape := %%%SPACE%%% 360# 361define config_filename 362ifneq ($$(CONFIG_$(1)),"") 363$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 364ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 365else 366ifeq ($$(wildcard $$($(1)_FILENAME)),) 367ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 368$(1)_SRCPREFIX := $(srctree)/ 369endif 370endif 371endif 372endif 373endef 374# 375############################################################################### 376 377# delete partially updated (i.e. corrupted) files on error 378.DELETE_ON_ERROR: 379