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
  11 ###
  12 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
  13 dot-target = $(dir $@).$(notdir $@)
  14
  15 ###
  16 # The temporary file to save gcc -MD generated dependencies must not
  17 # contain a comma
  18 depfile = $(subst $(comma),_,$(dot-target).d)
  19
  20 ###
  21 # filename of target with directory and extension stripped
  22 basetarget = $(basename $(notdir $@))
  23
  24 ###
  25 # filename of first prerequisite with directory and extension stripped
  26 baseprereq = $(basename $(notdir $<))
  27
  28 ###
  29 # Escape single quote for use in echo statements
  30 escsq = $(subst $(squote),'\$(squote)',$1)
  31
  32 ###
  33 # Easy method for doing a status message
  34        kecho := :
  35  quiet_kecho := echo
  36 silent_kecho := :
  37 kecho := $($(quiet)kecho)
  38
  39 ###
  40 # filechk is used to check if the content of a generated file is updated.
  41 # Sample usage:
  42 # define filechk_sample
  43 #       echo $KERNELRELEASE
  44 # endef
  45 # version.h : Makefile
  46 #       $(call filechk,sample)
  47 # The rule defined shall write to stdout the content of the new file.
  48 # The existing file will be compared with the new one.
  49 # - If no file exist it is created
  50 # - If the content differ the new file is used
  51 # - If they are equal no change, and no timestamp update
  52 # - stdin is piped in from the first prerequisite ($<) so one has
  53 #   to specify a valid file as first prerequisite (often the kbuild file)
  54 define filechk
  55         $(Q)set -e;                             \
  56         $(kecho) '  CHK     $@';                \
  57         mkdir -p $(dir $@);                     \
  58         $(filechk_$(1)) < $< > $@.tmp;          \
  59         if [ -r $@ ] && cmp -s $@ $@.tmp; then  \
  60                 rm -f $@.tmp;                   \
  61         else                                    \
  62                 $(kecho) '  UPD     $@';        \
  63                 mv -f $@.tmp $@;                \
  64         fi
  65 endef
  66
  67 ######
  68 # gcc support functions
  69 # See documentation in Documentation/kbuild/makefiles.txt
  70
  71 # cc-cross-prefix
  72 # Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
  73 # Return first prefix where a prefix$(CC) is found in PATH.
  74 # If no $(CC) found in PATH with listed prefixes return nothing
  75 cc-cross-prefix =  \
  76         $(word 1, $(foreach c,$(1),                                   \
  77                 $(shell set -e;                                       \
  78                 if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \
  79                         echo $(c);                                    \
  80                 fi)))
  81
  82 # output directory for tests below
  83 TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
  84
  85 # try-run
  86 # Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
  87 # Exit code chooses option. "$$TMP" is can be used as temporary file and
  88 # is automatically cleaned up.
  89 try-run = $(shell set -e;               \
  90         TMP="$(TMPOUT).$$$$.tmp";       \
  91         TMPO="$(TMPOUT).$$$$.o";        \
  92         if ($(1)) >/dev/null 2>&1;      \
  93         then echo "$(2)";               \
  94         else echo "$(3)";               \
  95         fi;                             \
  96         rm -f "$$TMP" "$$TMPO")
  97
  98 # as-option
  99 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
 100
 101 as-option = $(call try-run,\
 102         $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
 103
 104 # as-instr
 105 # Usage: cflags-y += $(call as-instr,instr,option1,option2)
 106
 107 as-instr = $(call try-run,\
 108         printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
 109
 110 # cc-option
 111 # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
 112
 113 cc-option = $(call try-run,\
 114         $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
 115
 116 # cc-option-yn
 117 # Usage: flag := $(call cc-option-yn,-march=winchip-c6)
 118 cc-option-yn = $(call try-run,\
 119         $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
 120
 121 # cc-option-align
 122 # Prefix align with either -falign or -malign
 123 cc-option-align = $(subst -functions=0,,\
 124         $(call cc-option,-falign-functions=0,-malign-functions=0))
 125
 126 # cc-disable-warning
 127 # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
 128 cc-disable-warning = $(call try-run,\
 129         $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
 130
 131 # cc-name
 132 # Expands to either gcc or clang
 133 cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)
 134
 135 # cc-version
 136 cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
 137
 138 # cc-fullversion
 139 cc-fullversion = $(shell $(CONFIG_SHELL) \
 140         $(srctree)/scripts/gcc-version.sh -p $(CC))
 141
 142 # cc-ifversion
 143 # Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
 144 cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
 145
 146 # cc-ldoption
 147 # Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
 148 cc-ldoption = $(call try-run,\
 149         $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
 150
 151 # ld-option
 152 # Usage: LDFLAGS += $(call ld-option, -X)
 153 ld-option = $(call try-run,\
 154         $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
 155
 156 # ar-option
 157 # Usage: KBUILD_ARFLAGS := $(call ar-option,D)
 158 # Important: no spaces around options
 159 ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
 160
 161 # ld-version
 162 # Note this is mainly for HJ Lu's 3 number binutil versions
 163 ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
 164
 165 # ld-ifversion
 166 # Usage:  $(call ld-ifversion, -ge, 22252, y)
 167 ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))
 168
 169 ######
 170
 171 ###
 172 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
 173 # Usage:
 174 # $(Q)$(MAKE) $(build)=dir
 175 build := -f $(srctree)/scripts/Makefile.build obj
 176
 177 ###
 178 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
 179 # Usage:
 180 # $(Q)$(MAKE) $(modbuiltin)=dir
 181 modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
 182
 183 ###
 184 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
 185 # Usage:
 186 # $(Q)$(MAKE) $(dtbinst)=dir
 187 dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj
 188
 189 ###
 190 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
 191 # Usage:
 192 # $(Q)$(MAKE) $(clean)=dir
 193 clean := -f $(srctree)/scripts/Makefile.clean obj
 194
 195 ###
 196 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
 197 # Usage:
 198 # $(Q)$(MAKE) $(hdr-inst)=dir
 199 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
 200
 201 # Prefix -I with $(srctree) if it is not an absolute path.
 202 # skip if -I has no parameter
 203 addtree = $(if $(patsubst -I%,%,$(1)), \
 204 $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1))
 205
 206 # Find all -I options and call addtree
 207 flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
 208
 209 # echo command.
 210 # Short version is used, if $(quiet) equals `quiet_', otherwise full one.
 211 echo-cmd = $(if $($(quiet)cmd_$(1)),\
 212         echo '  $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
 213
 214 # printing commands
 215 cmd = @$(echo-cmd) $(cmd_$(1))
 216
 217 # Add $(obj)/ for paths that are not absolute
 218 objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
 219
 220 ###
 221 # if_changed      - execute command if any prerequisite is newer than
 222 #                   target, or command line has changed
 223 # if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
 224 #                   including used config symbols
 225 # if_changed_rule - as if_changed but execute rule instead
 226 # See Documentation/kbuild/makefiles.txt for more info
 227
 228 ifneq ($(KBUILD_NOCMDDEP),1)
 229 # Check if both arguments has same arguments. Result is empty string if equal.
 230 # User may override this check using make KBUILD_NOCMDDEP=1
 231 arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
 232                     $(filter-out $(cmd_$@),   $(cmd_$(1))) )
 233 else
 234 arg-check = $(if $(strip $(cmd_$@)),,1)
 235 endif
 236
 237 # Replace >$< with >$$< to preserve $ when reloading the .cmd file
 238 # (needed for make)
 239 # Replace >#< with >\#< to avoid starting a comment in the .cmd file
 240 # (needed for make)
 241 # Replace >'< with >'\''< to be able to enclose the whole string in '...'
 242 # (needed for the shell)
 243 make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1)))))
 244
 245 # Find any prerequisites that is newer than target or that does not exist.
 246 # PHONY targets skipped in both cases.
 247 any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
 248
 249 # Execute command if command has changed or prerequisite(s) are updated.
 250 #
 251 if_changed = $(if $(strip $(any-prereq) $(arg-check)),                       \
 252         @set -e;                                                             \
 253         $(echo-cmd) $(cmd_$(1));                                             \
 254         printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
 255
 256 # Execute the command and also postprocess generated .d dependencies file.
 257 if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ),                  \
 258         @set -e;                                                             \
 259         $(cmd_and_fixdep), @:)
 260
 261 ifndef CONFIG_TRIM_UNUSED_KSYMS
 262
 263 cmd_and_fixdep =                                                             \
 264         $(echo-cmd) $(cmd_$(1));                                             \
 265         scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
 266         rm -f $(depfile);                                                    \
 267         mv -f $(dot-target).tmp $(dot-target).cmd;
 268
 269 else
 270
 271 # Filter out exported kernel symbol names from the preprocessor output.
 272 # See also __KSYM_DEPS__ in include/linux/export.h.
 273 # We disable the depfile generation here, so as not to overwrite the existing
 274 # depfile while fixdep is parsing it.
 275 flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1)))
 276 ksym_dep_filter =                                                            \
 277         case "$(1)" in                                                       \
 278           cc_*_c|cpp_i_c)                                                    \
 279             $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;;        \
 280           as_*_S|cpp_s_S)                                                    \
 281             $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;;        \
 282           boot*|build*|*cpp_lds_S|dtc|host*|vdso*) : ;;                      \
 283           *) echo "Don't know how to preprocess $(1)" >&2; false ;;          \
 284         esac | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p'
 285
 286 cmd_and_fixdep =                                                             \
 287         $(echo-cmd) $(cmd_$(1));                                             \
 288         $(ksym_dep_filter) |                                                 \
 289                 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)'          \
 290                         > $(dot-target).tmp;                                 \
 291         rm -f $(depfile);                                                    \
 292         mv -f $(dot-target).tmp $(dot-target).cmd;
 293
 294 endif
 295
 296 # Usage: $(call if_changed_rule,foo)
 297 # Will check if $(cmd_foo) or any of the prerequisites changed,
 298 # and if so will execute $(rule_foo).
 299 if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ),                 \
 300         @set -e;                                                             \
 301         $(rule_$(1)), @:)
 302
 303 ###
 304 # why - tell why a a target got build
 305 #       enabled by make V=2
 306 #       Output (listed in the order they are checked):
 307 #          (1) - due to target is PHONY
 308 #          (2) - due to target missing
 309 #          (3) - due to: file1.h file2.h
 310 #          (4) - due to command line change
 311 #          (5) - due to missing .cmd file
 312 #          (6) - due to target not in $(targets)
 313 # (1) PHONY targets are always build
 314 # (2) No target, so we better build it
 315 # (3) Prerequisite is newer than target
 316 # (4) The command line stored in the file named dir/.target.cmd
 317 #     differed from actual command line. This happens when compiler
 318 #     options changes
 319 # (5) No dir/.target.cmd file (used to store command line)
 320 # (6) No dir/.target.cmd file and target not listed in $(targets)
 321 #     This is a good hint that there is a bug in the kbuild file
 322 ifeq ($(KBUILD_VERBOSE),2)
 323 why =                                                                        \
 324     $(if $(filter $@, $(PHONY)),- due to target is PHONY,                    \
 325         $(if $(wildcard $@),                                                 \
 326             $(if $(strip $(any-prereq)),- due to: $(any-prereq),             \
 327                 $(if $(arg-check),                                           \
 328                     $(if $(cmd_$@),- due to command line change,             \
 329                         $(if $(filter $@, $(targets)),                       \
 330                             - due to missing .cmd file,                      \
 331                             - due to $(notdir $@) not in $$(targets)         \
 332                          )                                                   \
 333                      )                                                       \
 334                  )                                                           \
 335              ),                                                              \
 336              - due to target missing                                         \
 337          )                                                                   \
 338      )
 339
 340 echo-why = $(call escsq, $(strip $(why)))
 341 endif
 342
 343 ###############################################################################
 344 #
 345 # When a Kconfig string contains a filename, it is suitable for
 346 # passing to shell commands. It is surrounded by double-quotes, and
 347 # any double-quotes or backslashes within it are escaped by
 348 # backslashes.
 349 #
 350 # This is no use for dependencies or $(wildcard). We need to strip the
 351 # surrounding quotes and the escaping from quotes and backslashes, and
 352 # we *do* need to escape any spaces in the string. So, for example:
 353 #
 354 # Usage: $(eval $(call config_filename,FOO))
 355 #
 356 # Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
 357 # transformed as described above to be suitable for use within the
 358 # makefile.
 359 #
 360 # Also, if the filename is a relative filename and exists in the source
 361 # tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
 362 # be prefixed to *both* command invocation and dependencies.
 363 #
 364 # Note: We also print the filenames in the quiet_cmd_foo text, and
 365 # perhaps ought to have a version specially escaped for that purpose.
 366 # But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
 367 # enough.  It'll strip the quotes in the common case where there's no
 368 # space and it's a simple filename, and it'll retain the quotes when
 369 # there's a space. There are some esoteric cases in which it'll print
 370 # the wrong thing, but we don't really care. The actual dependencies
 371 # and commands *do* get it right, with various combinations of single
 372 # and double quotes, backslashes and spaces in the filenames.
 373 #
 374 ###############################################################################
 375 #
 376 space_escape := %%%SPACE%%%
 377 #
 378 define config_filename
 379 ifneq ($$(CONFIG_$(1)),"")
 380 $(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
 381 ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
 382 else
 383 ifeq ($$(wildcard $$($(1)_FILENAME)),)
 384 ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
 385 $(1)_SRCPREFIX := $(srctree)/
 386 endif
 387 endif
 388 endif
 389 endif
 390 endef
 391 #
 392 ###############################################################################