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# Escape single quote for use in echo statements 28escsq = $(subst $(squote),'\$(squote)',$1) 29 30### 31# Easy method for doing a status message 32 kecho := : 33 quiet_kecho := echo 34silent_kecho := : 35kecho := $($(quiet)kecho) 36 37### 38# filechk is used to check if the content of a generated file is updated. 39# Sample usage: 40# 41# filechk_sample = echo $(KERNELRELEASE) 42# version.h: FORCE 43# $(call filechk,sample) 44# 45# The rule defined shall write to stdout the content of the new file. 46# The existing file will be compared with the new one. 47# - If no file exist it is created 48# - If the content differ the new file is used 49# - If they are equal no change, and no timestamp update 50# - stdin is piped in from the first prerequisite ($<) so one has 51# to specify a valid file as first prerequisite (often the kbuild file) 52define filechk 53 $(Q)set -e; \ 54 mkdir -p $(dir $@); \ 55 { $(filechk_$(1)); } > $@.tmp; \ 56 if [ -r $@ ] && cmp -s $@ $@.tmp; then \ 57 rm -f $@.tmp; \ 58 else \ 59 $(kecho) ' UPD $@'; \ 60 mv -f $@.tmp $@; \ 61 fi 62endef 63 64###### 65# gcc support functions 66# See documentation in Documentation/kbuild/makefiles.txt 67 68# cc-cross-prefix 69# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-) 70# Return first prefix where a prefix$(CC) is found in PATH. 71# If no $(CC) found in PATH with listed prefixes return nothing 72cc-cross-prefix = \ 73 $(word 1, $(foreach c,$(1), \ 74 $(shell set -e; \ 75 if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \ 76 echo $(c); \ 77 fi))) 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-version 138cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) 139 140# cc-ifversion 141# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) 142cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4)) 143 144# cc-ldoption 145# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) 146cc-ldoption = $(call try-run,\ 147 $(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) 148 149# ld-option 150# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y) 151ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3)) 152 153# ar-option 154# Usage: KBUILD_ARFLAGS := $(call ar-option,D) 155# Important: no spaces around options 156ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) 157 158# ld-version 159# Note this is mainly for HJ Lu's 3 number binutil versions 160ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) 161 162# ld-ifversion 163# Usage: $(call ld-ifversion, -ge, 22252, y) 164ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) 165 166###### 167 168### 169# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= 170# Usage: 171# $(Q)$(MAKE) $(build)=dir 172build := -f $(srctree)/scripts/Makefile.build obj 173 174### 175# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= 176# Usage: 177# $(Q)$(MAKE) $(modbuiltin)=dir 178modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj 179 180### 181# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= 182# Usage: 183# $(Q)$(MAKE) $(dtbinst)=dir 184dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj 185 186### 187# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= 188# Usage: 189# $(Q)$(MAKE) $(clean)=dir 190clean := -f $(srctree)/scripts/Makefile.clean obj 191 192### 193# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= 194# Usage: 195# $(Q)$(MAKE) $(hdr-inst)=dir 196hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 197 198# Prefix -I with $(srctree) if it is not an absolute path. 199# skip if -I has no parameter 200addtree = $(if $(patsubst -I%,%,$(1)), \ 201$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1)) 202 203# Find all -I options and call addtree 204flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) 205 206# echo command. 207# Short version is used, if $(quiet) equals `quiet_', otherwise full one. 208echo-cmd = $(if $($(quiet)cmd_$(1)),\ 209 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) 210 211# printing commands 212cmd = @set -e; $(echo-cmd) $(cmd_$(1)) 213 214# Add $(obj)/ for paths that are not absolute 215objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) 216 217### 218# if_changed - execute command if any prerequisite is newer than 219# target, or command line has changed 220# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies 221# including used config symbols 222# if_changed_rule - as if_changed but execute rule instead 223# See Documentation/kbuild/makefiles.txt for more info 224 225ifneq ($(KBUILD_NOCMDDEP),1) 226# Check if both arguments are the same including their order. Result is empty 227# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 228arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ 229 $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) 230else 231arg-check = $(if $(strip $(cmd_$@)),,1) 232endif 233 234# Replace >$< with >$$< to preserve $ when reloading the .cmd file 235# (needed for make) 236# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file 237# (needed for make) 238# Replace >'< with >'\''< to be able to enclose the whole string in '...' 239# (needed for the shell) 240make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) 241 242# Find any prerequisites that is newer than target or that does not exist. 243# PHONY targets skipped in both cases. 244any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) 245 246# Execute command if command has changed or prerequisite(s) are updated. 247if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ 248 $(cmd); \ 249 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 250 251# Execute the command and also postprocess generated .d dependencies file. 252if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),$(cmd_and_fixdep),@:) 253 254cmd_and_fixdep = \ 255 $(cmd); \ 256 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\ 257 rm -f $(depfile) 258 259# Usage: $(call if_changed_rule,foo) 260# Will check if $(cmd_foo) or any of the prerequisites changed, 261# and if so will execute $(rule_foo). 262if_changed_rule = $(if $(strip $(any-prereq) $(arg-check)),$(rule_$(1)),@:) 263 264### 265# why - tell why a target got built 266# enabled by make V=2 267# Output (listed in the order they are checked): 268# (1) - due to target is PHONY 269# (2) - due to target missing 270# (3) - due to: file1.h file2.h 271# (4) - due to command line change 272# (5) - due to missing .cmd file 273# (6) - due to target not in $(targets) 274# (1) PHONY targets are always build 275# (2) No target, so we better build it 276# (3) Prerequisite is newer than target 277# (4) The command line stored in the file named dir/.target.cmd 278# differed from actual command line. This happens when compiler 279# options changes 280# (5) No dir/.target.cmd file (used to store command line) 281# (6) No dir/.target.cmd file and target not listed in $(targets) 282# This is a good hint that there is a bug in the kbuild file 283ifeq ($(KBUILD_VERBOSE),2) 284why = \ 285 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \ 286 $(if $(wildcard $@), \ 287 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \ 288 $(if $(arg-check), \ 289 $(if $(cmd_$@),- due to command line change, \ 290 $(if $(filter $@, $(targets)), \ 291 - due to missing .cmd file, \ 292 - due to $(notdir $@) not in $$(targets) \ 293 ) \ 294 ) \ 295 ) \ 296 ), \ 297 - due to target missing \ 298 ) \ 299 ) 300 301echo-why = $(call escsq, $(strip $(why))) 302endif 303 304############################################################################### 305# 306# When a Kconfig string contains a filename, it is suitable for 307# passing to shell commands. It is surrounded by double-quotes, and 308# any double-quotes or backslashes within it are escaped by 309# backslashes. 310# 311# This is no use for dependencies or $(wildcard). We need to strip the 312# surrounding quotes and the escaping from quotes and backslashes, and 313# we *do* need to escape any spaces in the string. So, for example: 314# 315# Usage: $(eval $(call config_filename,FOO)) 316# 317# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option, 318# transformed as described above to be suitable for use within the 319# makefile. 320# 321# Also, if the filename is a relative filename and exists in the source 322# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to 323# be prefixed to *both* command invocation and dependencies. 324# 325# Note: We also print the filenames in the quiet_cmd_foo text, and 326# perhaps ought to have a version specially escaped for that purpose. 327# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good 328# enough. It'll strip the quotes in the common case where there's no 329# space and it's a simple filename, and it'll retain the quotes when 330# there's a space. There are some esoteric cases in which it'll print 331# the wrong thing, but we don't really care. The actual dependencies 332# and commands *do* get it right, with various combinations of single 333# and double quotes, backslashes and spaces in the filenames. 334# 335############################################################################### 336# 337define config_filename 338ifneq ($$(CONFIG_$(1)),"") 339$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) 340ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME))) 341else 342ifeq ($$(wildcard $$($(1)_FILENAME)),) 343ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),) 344$(1)_SRCPREFIX := $(srctree)/ 345endif 346endif 347endif 348endif 349endef 350# 351############################################################################### 352 353# delete partially updated (i.e. corrupted) files on error 354.DELETE_ON_ERROR: 355 356# do not delete intermediate files automatically 357.SECONDARY: 358