1#### 2# kbuild: Generic definitions 3 4# Convenient variables 5comma := , 6quote := " 7squote := ' 8empty := 9space := $(empty) $(empty) 10space_escape := _-_SPACE_-_ 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))/) 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.) 118CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) 119 120# cc-option 121# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) 122 123cc-option = $(call __cc-option, $(CC),\ 124 $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2)) 125 126# hostcc-option 127# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) 128hostcc-option = $(call __cc-option, $(HOSTCC),\ 129 $(HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) 130 131# cc-option-yn 132# Usage: flag := $(call cc-option-yn,-march=winchip-c6) 133cc-option-yn = $(call try-run,\ 134 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) 135 136# cc-disable-warning 137# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) 138cc-disable-warning = $(call try-run,\ 139 $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) 140 141# cc-name 142# Expands to either gcc or clang 143cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc) 144 145# cc-version 146cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) 147 148# cc-fullversion 149cc-fullversion = $(shell $(CONFIG_SHELL) \ 150 $(srctree)/scripts/gcc-version.sh -p $(CC)) 151 152# cc-ifversion 153# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) 154cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4)) 155 156# cc-if-fullversion 157# Usage: EXTRA_CFLAGS += $(call cc-if-fullversion, -lt, 040502, -O1) 158cc-if-fullversion = $(shell [ $(cc-fullversion) $(1) $(2) ] && echo $(3) || echo $(4)) 159 160# cc-ldoption 161# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 162cc-ldoption = $(call try-run,\ 163 $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 164 165# ld-option 166# Usage: LDFLAGS += $(call ld-option, -X) 167ld-option = $(call try-run,\ 168 $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2)) 169 170# ar-option 171# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 172# Important: no spaces around options 173ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 174 175# ld-version 176# Note this is mainly for HJ Lu's 3 number binutil versions 177ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 178 179# ld-ifversion 180# Usage: $(call ld-ifversion, -ge, 22252, y) 181ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 182 183###### 184 185### 186# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 187# Usage: 188# $(Q)$(MAKE) $(build)=dir 189build := -f $(srctree)/scripts/Makefile.build obj 190 191### 192# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 193# Usage: 194# $(Q)$(MAKE) $(modbuiltin)=dir 195modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 196 197### 198# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 199# Usage: 200# $(Q)$(MAKE) $(dtbinst)=dir 201dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj 202 203### 204# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 205# Usage: 206# $(Q)$(MAKE) $(clean)=dir 207clean := -f $(srctree)/scripts/Makefile.clean obj 208 209### 210# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 211# Usage: 212# $(Q)$(MAKE) $(hdr-inst)=dir 213hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 214 215# Prefix -I with $(srctree) if it is not an absolute path. 216# skip if -I has no parameter 217addtree = $(if $(patsubst -I%,%,$(1)), \ 218$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1))) 219 220# Find all -I options and call addtree 221flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 222 223# echo command. 224# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 225echo-cmd = $(if $($(quiet)cmd_$(1)),\ 226 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 227 228# printing commands 229cmd = @$(echo-cmd) $(cmd_$(1)) 230 231# Add $(obj)/ for paths that are not absolute 232objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 233 234### 235# if_changed - execute command if any prerequisite is newer than 236# target, or command line has changed 237# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 238# including used config symbols 239# if_changed_rule - as if_changed but execute rule instead 240# See Documentation/kbuild/makefiles.txt for more info 241 242ifneq ($(KBUILD_NOCMDDEP),1) 243# Check if both arguments are the same including their order. Result is empty 244# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 245arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 246 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 247else 248arg-check = $(if $(strip $(cmd_$@)),,1) 249endif 250 251# Replace >$< with >$$< to preserve $ when reloading the .cmd file 252# (needed for make) 253# Replace >#< with >\#< to avoid starting a comment in the .cmd file 254# (needed for make) 255# Replace >'< with >'\''< to be able to enclose the whole string in '...' 256# (needed for the shell) 257make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1))))) 258 259# Find any prerequisites that is newer than target or that does not exist. 260# PHONY targets skipped in both cases. 261any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 262 263# Execute command if command has changed or prerequisite(s) are updated. 264if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 265 @set -e; \ 266 $(echo-cmd) $(cmd_$(1)); \ 267 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 268 269# Execute the command and also postprocess generated .d dependencies file. 270if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ 271 @set -e; \ 272 $(cmd_and_fixdep), @:) 273 274ifndef CONFIG_TRIM_UNUSED_KSYMS 275 276cmd_and_fixdep = \ 277 $(echo-cmd) $(cmd_$(1)); \ 278 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ 279 rm -f $(depfile); \ 280 mv -f $(dot-target).tmp $(dot-target).cmd; 281 282else 283 284# Filter out exported kernel symbol names from the preprocessor output. 285# See also __KSYM_DEPS__ in include/linux/export.h. 286# We disable the depfile generation here, so as not to overwrite the existing 287# depfile while fixdep is parsing it. 288flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1))) 289ksym_dep_filter = \ 290 case "$(1)" in \ 291 cc_*_c|cpp_i_c) \ 292 $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \ 293 as_*_S|cpp_s_S) \ 294 $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \ 295 boot*|build*|cpp_its_S|*cpp_lds_S|dtc|host*|vdso*) : ;; \ 296 *) echo "Don't know how to preprocess $(1)" >&2; false ;; \ 297 esac | tr ";" "\n" | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p' 298 299cmd_and_fixdep = \ 300 $(echo-cmd) $(cmd_$(1)); \ 301 $(ksym_dep_filter) | \ 302 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \ 303 > $(dot-target).tmp; \ 304 rm -f $(depfile); \ 305 mv -f $(dot-target).tmp $(dot-target).cmd; 306 307endif 308 309# Usage: $(call if_changed_rule,foo) 310# Will check if $(cmd_foo) or any of the prerequisites changed, 311# and if so will execute $(rule_foo). 312if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \ 313 @set -e; \ 314 $(rule_$(1)), @:) 315 316### 317# why - tell why a target got built 318# enabled by make V=2 319# Output (listed in the order they are checked): 320# (1) - due to target is PHONY 321# (2) - due to target missing 322# (3) - due to: file1.h file2.h 323# (4) - due to command line change 324# (5) - due to missing .cmd file 325# (6) - due to target not in $(targets) 326# (1) PHONY targets are always build 327# (2) No target, so we better build it 328# (3) Prerequisite is newer than target 329# (4) The command line stored in the file named dir/.target.cmd 330# differed from actual command line. This happens when compiler 331# options changes 332# (5) No dir/.target.cmd file (used to store command line) 333# (6) No dir/.target.cmd file and target not listed in $(targets) 334# This is a good hint that there is a bug in the kbuild file 335ifeq ($(KBUILD_VERBOSE),2) 336why = \ 337 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 338 $(if $(wildcard $@), \ 339 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 340 $(if $(arg-check), \ 341 $(if $(cmd_$@),- due to command line change, \ 342 $(if $(filter $@, $(targets)), \ 343 - due to missing .cmd file, \ 344 - due to $(notdir $@) not in $$(targets) \ 345 ) \ 346 ) \ 347 ) \ 348 ), \ 349 - due to target missing \ 350 ) \ 351 ) 352 353echo-why = $(call escsq, $(strip $(why))) 354endif 355 356############################################################################### 357# 358# When a Kconfig string contains a filename, it is suitable for 359# passing to shell commands. It is surrounded by double-quotes, and 360# any double-quotes or backslashes within it are escaped by 361# backslashes. 362# 363# This is no use for dependencies or $(wildcard). We need to strip the 364# surrounding quotes and the escaping from quotes and backslashes, and 365# we *do* need to escape any spaces in the string. So, for example: 366# 367# Usage: $(eval $(call config_filename,FOO)) 368# 369# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 370# transformed as described above to be suitable for use within the 371# makefile. 372# 373# Also, if the filename is a relative filename and exists in the source 374# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 375# be prefixed to *both* command invocation and dependencies. 376# 377# Note: We also print the filenames in the quiet_cmd_foo text, and 378# perhaps ought to have a version specially escaped for that purpose. 379# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 380# enough. It'll strip the quotes in the common case where there's no 381# space and it's a simple filename, and it'll retain the quotes when 382# there's a space. There are some esoteric cases in which it'll print 383# the wrong thing, but we don't really care. The actual dependencies 384# and commands *do* get it right, with various combinations of single 385# and double quotes, backslashes and spaces in the filenames. 386# 387############################################################################### 388# 389define config_filename 390ifneq ($$(CONFIG_$(1)),"") 391$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 392ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 393else 394ifeq ($$(wildcard $$($(1)_FILENAME)),) 395ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 396$(1)_SRCPREFIX := $(srctree)/ 397endif 398endif 399endif 400endif 401endef 402# 403############################################################################### 404