scripts/Kbuild.include

   1 ####
   2 # kbuild: Generic definitions
   3
   4 # Convenient variables
   5 comma   := ,
   6 quote   := "
   7 squote  := '
   8 empty   :=
   9 space   := $(empty) $(empty)
  10 space_escape := _-_SPACE_-_
  11
  12 ###
  13 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
  14 dot-target = $(dir $@).$(notdir $@)
  15
  16 ###
  17 # The temporary file to save gcc -MD generated dependencies must not
  18 # contain a comma
  19 depfile = $(subst $(comma),_,$(dot-target).d)
  20
  21 ###
  22 # filename of target with directory and extension stripped
  23 basetarget = $(basename $(notdir $@))
  24
  25 ###
  26 # filename of first prerequisite with directory and extension stripped
  27 baseprereq = $(basename $(notdir $<))
  28
  29 ###
  30 # Escape single quote for use in echo statements
  31 escsq = $(subst $(squote),'\$(squote)',$1)
  32
  33 ###
  34 # Easy method for doing a status message
  35        kecho := :
  36  quiet_kecho := echo
  37 silent_kecho := :
  38 kecho := $($(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)
  55 define 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
  66 endef
  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
  76 cc-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
  84 TMPOUT := $(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.
  90 try-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" "$$TMPO")
  98
  99 # as-option
 100 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
 101
 102 as-option = $(call try-run,\
 103         $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
 104
 105 # as-instr
 106 # Usage: cflags-y += $(call as-instr,instr,option1,option2)
 107
 108 as-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.)
 118 CC_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
 123 cc-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)
 128 hostcc-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)
 133 cc-option-yn = $(call try-run,\
 134         $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
 135
 136 # cc-disable-warning
 137 # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
 138 cc-disable-warning = $(call try-run,\
 139         $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
 140
 141 # cc-name
 142 # Expands to either gcc or clang
 143 cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)
 144
 145 # cc-version
 146 cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
 147
 148 # cc-fullversion
 149 cc-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)
 154 cc-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)
 158 cc-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)
 162 cc-ldoption = $(call try-run,\
 163         $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
 164
 165 # ld-option
 166 # Usage: LDFLAGS += $(call ld-option, -X)
 167 ld-option = $(call try-run,\
 168         $(CC) -x c /dev/null -c -o "$$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
 173 ar-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
 177 ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
 178
 179 # ld-ifversion
 180 # Usage:  $(call ld-ifversion, -ge, 22252, y)
 181 ld-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
 189 build := -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
 195 modbuiltin := -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
 201 dtbinst := -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
 207 clean := -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
 213 hdr-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
 217 addtree = $(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
 221 flags = $(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.
 225 echo-cmd = $(if $($(quiet)cmd_$(1)),\
 226         echo '  $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
 227
 228 # printing commands
 229 cmd = @$(echo-cmd) $(cmd_$(1))
 230
 231 # Add $(obj)/ for paths that are not absolute
 232 objectify = $(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
 242 ifneq ($(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
 245 arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
 246                          $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
 247 else
 248 arg-check = $(if $(strip $(cmd_$@)),,1)
 249 endif
 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)
 257 make-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.
 261 any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
 262
 263 # Execute command if command has changed or prerequisite(s) are updated.
 264 if_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.
 270 if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ),                  \
 271         @set -e;                                                             \
 272         $(cmd_and_fixdep), @:)
 273
 274 ifndef CONFIG_TRIM_UNUSED_KSYMS
 275
 276 cmd_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
 282 else
 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.
 288 flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1)))
 289 ksym_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
 299 cmd_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
 307 endif
 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).
 312 if_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 $(targets)
 334 #     This is a good hint that there is a bug in the kbuild file
 335 ifeq ($(KBUILD_VERBOSE),2)
 336 why =                                                                        \
 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
 353 echo-why = $(call escsq, $(strip $(why)))
 354 endif
 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 #
 389 define config_filename
 390 ifneq ($$(CONFIG_$(1)),"")
 391 $(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
 392 ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
 393 else
 394 ifeq ($$(wildcard $$($(1)_FILENAME)),)
 395 ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
 396 $(1)_SRCPREFIX := $(srctree)/
 397 endif
 398 endif
 399 endif
 400 endif
 401 endef
 402 #
 403 ###############################################################################