Makefile

   1 VERSION = 2
   2 PATCHLEVEL = 6
   3 SUBLEVEL = 25
   4 EXTRAVERSION = -rc7
   5 NAME = Funky Weasel is Jiggy wit it
   6
   7 # *DOCUMENTATION*
   8 # To see a list of typical targets execute "make help"
   9 # More info can be located in ./README
  10 # Comments in this file are targeted only to the developer, do not
  11 # expect to learn how to build the kernel reading this file.
  12
  13 # Do not:
  14 # o  use make's built-in rules and variables
  15 #    (this increases performance and avoids hard-to-debug behaviour);
  16 # o  print "Entering directory ...";
  17 MAKEFLAGS += -rR --no-print-directory
  18
  19 # We are using a recursive build, so we need to do a little thinking
  20 # to get the ordering right.
  21 #
  22 # Most importantly: sub-Makefiles should only ever modify files in
  23 # their own directory. If in some directory we have a dependency on
  24 # a file in another dir (which doesn't happen often, but it's often
  25 # unavoidable when linking the built-in.o targets which finally
  26 # turn into vmlinux), we will call a sub make in that other dir, and
  27 # after that we are sure that everything which is in that other dir
  28 # is now up to date.
  29 #
  30 # The only cases where we need to modify files which have global
  31 # effects are thus separated out and done before the recursive
  32 # descending is started. They are now explicitly listed as the
  33 # prepare rule.
  34
  35 # To put more focus on warnings, be less verbose as default
  36 # Use 'make V=1' to see the full commands
  37
  38 ifdef V
  39   ifeq ("$(origin V)", "command line")
  40     KBUILD_VERBOSE = $(V)
  41   endif
  42 endif
  43 ifndef KBUILD_VERBOSE
  44   KBUILD_VERBOSE = 0
  45 endif
  46
  47 # Call a source code checker (by default, "sparse") as part of the
  48 # C compilation.
  49 #
  50 # Use 'make C=1' to enable checking of only re-compiled files.
  51 # Use 'make C=2' to enable checking of *all* source files, regardless
  52 # of whether they are re-compiled or not.
  53 #
  54 # See the file "Documentation/sparse.txt" for more details, including
  55 # where to get the "sparse" utility.
  56
  57 ifdef C
  58   ifeq ("$(origin C)", "command line")
  59     KBUILD_CHECKSRC = $(C)
  60   endif
  61 endif
  62 ifndef KBUILD_CHECKSRC
  63   KBUILD_CHECKSRC = 0
  64 endif
  65
  66 # Use make M=dir to specify directory of external module to build
  67 # Old syntax make ... SUBDIRS=$PWD is still supported
  68 # Setting the environment variable KBUILD_EXTMOD take precedence
  69 ifdef SUBDIRS
  70   KBUILD_EXTMOD ?= $(SUBDIRS)
  71 endif
  72 ifdef M
  73   ifeq ("$(origin M)", "command line")
  74     KBUILD_EXTMOD := $(M)
  75   endif
  76 endif
  77
  78
  79 # kbuild supports saving output files in a separate directory.
  80 # To locate output files in a separate directory two syntaxes are supported.
  81 # In both cases the working directory must be the root of the kernel src.
  82 # 1) O=
  83 # Use "make O=dir/to/store/output/files/"
  84 #
  85 # 2) Set KBUILD_OUTPUT
  86 # Set the environment variable KBUILD_OUTPUT to point to the directory
  87 # where the output files shall be placed.
  88 # export KBUILD_OUTPUT=dir/to/store/output/files/
  89 # make
  90 #
  91 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
  92 # variable.
  93
  94
  95 # KBUILD_SRC is set on invocation of make in OBJ directory
  96 # KBUILD_SRC is not intended to be used by the regular user (for now)
  97 ifeq ($(KBUILD_SRC),)
  98
  99 # OK, Make called in directory where kernel src resides
 100 # Do we want to locate output files in a separate directory?
 101 ifdef O
 102   ifeq ("$(origin O)", "command line")
 103     KBUILD_OUTPUT := $(O)
 104   endif
 105 endif
 106
 107 # That's our default target when none is given on the command line
 108 PHONY := _all
 109 _all:
 110
 111 # Cancel implicit rules on top Makefile
 112 $(CURDIR)/Makefile Makefile: ;
 113
 114 ifneq ($(KBUILD_OUTPUT),)
 115 # Invoke a second make in the output directory, passing relevant variables
 116 # check that the output directory actually exists
 117 saved-output := $(KBUILD_OUTPUT)
 118 KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
 119 $(if $(KBUILD_OUTPUT),, \
 120      $(error output directory "$(saved-output)" does not exist))
 121
 122 PHONY += $(MAKECMDGOALS) sub-make
 123
 124 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
 125         $(Q)@:
 126
 127 sub-make: FORCE
 128         $(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
 129         KBUILD_SRC=$(CURDIR) \
 130         KBUILD_EXTMOD="$(KBUILD_EXTMOD)" -f $(CURDIR)/Makefile \
 131         $(filter-out _all sub-make,$(MAKECMDGOALS))
 132
 133 # Leave processing to above invocation of make
 134 skip-makefile := 1
 135 endif # ifneq ($(KBUILD_OUTPUT),)
 136 endif # ifeq ($(KBUILD_SRC),)
 137
 138 # We process the rest of the Makefile if this is the final invocation of make
 139 ifeq ($(skip-makefile),)
 140
 141 # If building an external module we do not care about the all: rule
 142 # but instead _all depend on modules
 143 PHONY += all
 144 ifeq ($(KBUILD_EXTMOD),)
 145 _all: all
 146 else
 147 _all: modules
 148 endif
 149
 150 srctree         := $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
 151 TOPDIR          := $(srctree)
 152 # FIXME - TOPDIR is obsolete, use srctree/objtree
 153 objtree         := $(CURDIR)
 154 src             := $(srctree)
 155 obj             := $(objtree)
 156
 157 VPATH           := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
 158
 159 export srctree objtree VPATH TOPDIR
 160
 161
 162 # SUBARCH tells the usermode build what the underlying arch is.  That is set
 163 # first, and if a usermode build is happening, the "ARCH=um" on the command
 164 # line overrides the setting of ARCH below.  If a native build is happening,
 165 # then ARCH is assigned, getting whatever value it gets normally, and
 166 # SUBARCH is subsequently ignored.
 167
 168 SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
 169                                   -e s/arm.*/arm/ -e s/sa110/arm/ \
 170                                   -e s/s390x/s390/ -e s/parisc64/parisc/ \
 171                                   -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
 172                                   -e s/sh.*/sh/ )
 173
 174 # Cross compiling and selecting different set of gcc/bin-utils
 175 # ---------------------------------------------------------------------------
 176 #
 177 # When performing cross compilation for other architectures ARCH shall be set
 178 # to the target architecture. (See arch/* for the possibilities).
 179 # ARCH can be set during invocation of make:
 180 # make ARCH=ia64
 181 # Another way is to have ARCH set in the environment.
 182 # The default ARCH is the host where make is executed.
 183
 184 # CROSS_COMPILE specify the prefix used for all executables used
 185 # during compilation. Only gcc and related bin-utils executables
 186 # are prefixed with $(CROSS_COMPILE).
 187 # CROSS_COMPILE can be set on the command line
 188 # make CROSS_COMPILE=ia64-linux-
 189 # Alternatively CROSS_COMPILE can be set in the environment.
 190 # Default value for CROSS_COMPILE is not to prefix executables
 191 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 192
 193 export KBUILD_BUILDHOST := $(SUBARCH)
 194 ARCH            ?= mips
 195 CROSS_COMPILE   ?=
 196
 197 # Architecture as present in compile.h
 198 UTS_MACHINE     := $(ARCH)
 199 SRCARCH         := $(ARCH)
 200
 201 # Additional ARCH settings for x86
 202 ifeq ($(ARCH),i386)
 203         SRCARCH := x86
 204 endif
 205 ifeq ($(ARCH),x86_64)
 206         SRCARCH := x86
 207 endif
 208
 209 KCONFIG_CONFIG  ?= .config
 210
 211 # SHELL used by kbuild
 212 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
 213           else if [ -x /bin/bash ]; then echo /bin/bash; \
 214           else echo sh; fi ; fi)
 215
 216 HOSTCC       = gcc
 217 HOSTCXX      = g++
 218 HOSTCFLAGS   = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer
 219 HOSTCXXFLAGS = -O2
 220
 221 # Decide whether to build built-in, modular, or both.
 222 # Normally, just do built-in.
 223
 224 KBUILD_MODULES :=
 225 KBUILD_BUILTIN := 1
 226
 227 #       If we have only "make modules", don't compile built-in objects.
 228 #       When we're building modules with modversions, we need to consider
 229 #       the built-in objects during the descend as well, in order to
 230 #       make sure the checksums are up to date before we record them.
 231
 232 ifeq ($(MAKECMDGOALS),modules)
 233   KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
 234 endif
 235
 236 #       If we have "make <whatever> modules", compile modules
 237 #       in addition to whatever we do anyway.
 238 #       Just "make" or "make all" shall build modules as well
 239
 240 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
 241   KBUILD_MODULES := 1
 242 endif
 243
 244 ifeq ($(MAKECMDGOALS),)
 245   KBUILD_MODULES := 1
 246 endif
 247
 248 export KBUILD_MODULES KBUILD_BUILTIN
 249 export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
 250
 251 # Beautify output
 252 # ---------------------------------------------------------------------------
 253 #
 254 # Normally, we echo the whole command before executing it. By making
 255 # that echo $($(quiet)$(cmd)), we now have the possibility to set
 256 # $(quiet) to choose other forms of output instead, e.g.
 257 #
 258 #         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
 259 #         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
 260 #
 261 # If $(quiet) is empty, the whole command will be printed.
 262 # If it is set to "quiet_", only the short version will be printed.
 263 # If it is set to "silent_", nothing will be printed at all, since
 264 # the variable $(silent_cmd_cc_o_c) doesn't exist.
 265 #
 266 # A simple variant is to prefix commands with $(Q) - that's useful
 267 # for commands that shall be hidden in non-verbose mode.
 268 #
 269 #       $(Q)ln $@ :<
 270 #
 271 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
 272 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
 273
 274 ifeq ($(KBUILD_VERBOSE),1)
 275   quiet =
 276   Q =
 277 else
 278   quiet=quiet_
 279   Q = @
 280 endif
 281
 282 # If the user is running make -s (silent mode), suppress echoing of
 283 # commands
 284
 285 ifneq ($(findstring s,$(MAKEFLAGS)),)
 286   quiet=silent_
 287 endif
 288
 289 export quiet Q KBUILD_VERBOSE
 290
 291
 292 # Look for make include files relative to root of kernel src
 293 MAKEFLAGS += --include-dir=$(srctree)
 294
 295 # We need some generic definitions (do not try to remake the file).
 296 $(srctree)/scripts/Kbuild.include: ;
 297 include $(srctree)/scripts/Kbuild.include
 298
 299 # Make variables (CC, etc...)
 300
 301 AS              = $(CROSS_COMPILE)as
 302 LD              = $(CROSS_COMPILE)ld
 303 CC              = $(CROSS_COMPILE)gcc
 304 CPP             = $(CC) -E
 305 AR              = $(CROSS_COMPILE)ar
 306 NM              = $(CROSS_COMPILE)nm
 307 STRIP           = $(CROSS_COMPILE)strip
 308 OBJCOPY         = $(CROSS_COMPILE)objcopy
 309 OBJDUMP         = $(CROSS_COMPILE)objdump
 310 AWK             = awk
 311 GENKSYMS        = scripts/genksyms/genksyms
 312 DEPMOD          = /sbin/depmod
 313 KALLSYMS        = scripts/kallsyms
 314 PERL            = perl
 315 CHECK           = sparse
 316
 317 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ -Wbitwise $(CF)
 318 MODFLAGS        = -DMODULE
 319 CFLAGS_MODULE   = $(MODFLAGS)
 320 AFLAGS_MODULE   = $(MODFLAGS)
 321 LDFLAGS_MODULE  =
 322 CFLAGS_KERNEL   =
 323 AFLAGS_KERNEL   =
 324
 325
 326 # Use LINUXINCLUDE when you must reference the include/ directory.
 327 # Needed to be compatible with the O= option
 328 LINUXINCLUDE    := -Iinclude \
 329                    $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include) \
 330                    -include include/linux/autoconf.h
 331
 332 KBUILD_CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE)
 333
 334 KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
 335                    -fno-strict-aliasing -fno-common \
 336                    -Werror-implicit-function-declaration
 337 KBUILD_AFLAGS   := -D__ASSEMBLY__
 338
 339 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 340 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 341 KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
 342
 343 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 344 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
 345 export CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE
 346 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
 347
 348 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
 349 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 350 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 351
 352 # When compiling out-of-tree modules, put MODVERDIR in the module
 353 # tree rather than in the kernel tree. The kernel tree might
 354 # even be read-only.
 355 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
 356
 357 # Files to ignore in find ... statements
 358
 359 RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS -o -name .pc -o -name .hg -o -name .git \) -prune -o
 360 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn --exclude CVS --exclude .pc --exclude .hg --exclude .git
 361
 362 # ===========================================================================
 363 # Rules shared between *config targets and build targets
 364
 365 # Basic helpers built in scripts/
 366 PHONY += scripts_basic
 367 scripts_basic:
 368         $(Q)$(MAKE) $(build)=scripts/basic
 369
 370 # To avoid any implicit rule to kick in, define an empty command.
 371 scripts/basic/%: scripts_basic ;
 372
 373 PHONY += outputmakefile
 374 # outputmakefile generates a Makefile in the output directory, if using a
 375 # separate output directory. This allows convenient use of make in the
 376 # output directory.
 377 outputmakefile:
 378 ifneq ($(KBUILD_SRC),)
 379         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
 380             $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
 381 endif
 382
 383 # To make sure we do not include .config for any of the *config targets
 384 # catch them early, and hand them over to scripts/kconfig/Makefile
 385 # It is allowed to specify more targets when calling make, including
 386 # mixing *config targets and build targets.
 387 # For example 'make oldconfig all'.
 388 # Detect when mixed targets is specified, and make a second invocation
 389 # of make so .config is not included in this case either (for *config).
 390
 391 no-dot-config-targets := clean mrproper distclean \
 392                          cscope TAGS tags help %docs check% \
 393                          include/linux/version.h headers_% \
 394                          kernelrelease kernelversion
 395
 396 config-targets := 0
 397 mixed-targets  := 0
 398 dot-config     := 1
 399
 400 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 401         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 402                 dot-config := 0
 403         endif
 404 endif
 405
 406 ifeq ($(KBUILD_EXTMOD),)
 407         ifneq ($(filter config %config,$(MAKECMDGOALS)),)
 408                 config-targets := 1
 409                 ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
 410                         mixed-targets := 1
 411                 endif
 412         endif
 413 endif
 414
 415 ifeq ($(mixed-targets),1)
 416 # ===========================================================================
 417 # We're called with mixed targets (*config and build targets).
 418 # Handle them one by one.
 419
 420 %:: FORCE
 421         $(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@
 422
 423 else
 424 ifeq ($(config-targets),1)
 425 # ===========================================================================
 426 # *config targets only - make sure prerequisites are updated, and descend
 427 # in scripts/kconfig to make the *config target
 428
 429 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 430 # KBUILD_DEFCONFIG may point out an alternative default configuration
 431 # used for 'make defconfig'
 432 include $(srctree)/arch/$(SRCARCH)/Makefile
 433 export KBUILD_DEFCONFIG
 434
 435 config %config: scripts_basic outputmakefile FORCE
 436         $(Q)mkdir -p include/linux include/config
 437         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 438
 439 else
 440 # ===========================================================================
 441 # Build targets only - this includes vmlinux, arch specific targets, clean
 442 # targets and others. In general all targets except *config targets.
 443
 444 ifeq ($(KBUILD_EXTMOD),)
 445 # Additional helpers built in scripts/
 446 # Carefully list dependencies so we do not try to build scripts twice
 447 # in parallel
 448 PHONY += scripts
 449 scripts: scripts_basic include/config/auto.conf
 450         $(Q)$(MAKE) $(build)=$(@)
 451
 452 # Objects we will link into vmlinux / subdirs we need to visit
 453 init-y          := init/
 454 drivers-y       := drivers/ sound/
 455 net-y           := net/
 456 libs-y          := lib/
 457 core-y          := usr/
 458 endif # KBUILD_EXTMOD
 459
 460 ifeq ($(dot-config),1)
 461 # Read in config
 462 -include include/config/auto.conf
 463
 464 ifeq ($(KBUILD_EXTMOD),)
 465 # Read in dependencies to all Kconfig* files, make sure to run
 466 # oldconfig if changes are detected.
 467 -include include/config/auto.conf.cmd
 468
 469 # To avoid any implicit rule to kick in, define an empty command
 470 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
 471
 472 # If .config is newer than include/config/auto.conf, someone tinkered
 473 # with it and forgot to run make oldconfig.
 474 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
 475 # we execute the config step to be sure to catch updated Kconfig files
 476 include/config/auto.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
 477         $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
 478 else
 479 # external modules needs include/linux/autoconf.h and include/config/auto.conf
 480 # but do not care if they are up-to-date. Use auto.conf to trigger the test
 481 PHONY += include/config/auto.conf
 482
 483 include/config/auto.conf:
 484         $(Q)test -e include/linux/autoconf.h -a -e $@ || (              \
 485         echo;                                                           \
 486         echo "  ERROR: Kernel configuration is invalid.";               \
 487         echo "         include/linux/autoconf.h or $@ are missing.";    \
 488         echo "         Run 'make oldconfig && make prepare' on kernel src to fix it.";  \
 489         echo;                                                           \
 490         /bin/false)
 491
 492 endif # KBUILD_EXTMOD
 493
 494 else
 495 # Dummy target needed, because used as prerequisite
 496 include/config/auto.conf: ;
 497 endif # $(dot-config)
 498
 499 # The all: target is the default when no target is given on the
 500 # command line.
 501 # This allow a user to issue only 'make' to build a kernel including modules
 502 # Defaults vmlinux but it is usually overridden in the arch makefile
 503 all: vmlinux
 504
 505 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 506 KBUILD_CFLAGS   += -Os
 507 else
 508 KBUILD_CFLAGS   += -O2
 509 endif
 510
 511 # Force gcc to behave correct even for buggy distributions
 512 # Arch Makefiles may override this setting
 513 KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector)
 514
 515 include $(srctree)/arch/$(SRCARCH)/Makefile
 516
 517 ifdef CONFIG_FRAME_POINTER
 518 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 519 else
 520 KBUILD_CFLAGS   += -fomit-frame-pointer
 521 endif
 522
 523 ifdef CONFIG_DEBUG_INFO
 524 KBUILD_CFLAGS   += -g
 525 KBUILD_AFLAGS   += -gdwarf-2
 526 endif
 527
 528 # We trigger additional mismatches with less inlining
 529 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 530 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 531 endif
 532
 533 # arch Makefile may override CC so keep this after arch Makefile is included
 534 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 535 CHECKFLAGS     += $(NOSTDINC_FLAGS)
 536
 537 # warn about C99 declaration after statement
 538 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
 539
 540 # disable pointer signed / unsigned warnings in gcc 4.0
 541 KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,)
 542
 543 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
 544 # But warn user when we do so
 545 warn-assign = \
 546 $(warning "WARNING: Appending $$K$(1) ($(K$(1))) from $(origin K$(1)) to kernel $$$(1)")
 547
 548 ifneq ($(KCPPFLAGS),)
 549         $(call warn-assign,CPPFLAGS)
 550         KBUILD_CPPFLAGS += $(KCPPFLAGS)
 551 endif
 552 ifneq ($(KAFLAGS),)
 553         $(call warn-assign,AFLAGS)
 554         KBUILD_AFLAGS += $(KAFLAGS)
 555 endif
 556 ifneq ($(KCFLAGS),)
 557         $(call warn-assign,CFLAGS)
 558         KBUILD_CFLAGS += $(KCFLAGS)
 559 endif
 560
 561 # Use --build-id when available.
 562 LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
 563                               $(call ld-option, -Wl$(comma)--build-id,))
 564 LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
 565 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
 566
 567 # Default kernel image to build when no specific target is given.
 568 # KBUILD_IMAGE may be overruled on the command line or
 569 # set in the environment
 570 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
 571 # this default value
 572 export KBUILD_IMAGE ?= vmlinux
 573
 574 #
 575 # INSTALL_PATH specifies where to place the updated kernel and system map
 576 # images. Default is /boot, but you can set it to other values
 577 export  INSTALL_PATH ?= /boot
 578
 579 #
 580 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
 581 # relocations required by build roots.  This is not defined in the
 582 # makefile but the argument can be passed to make if needed.
 583 #
 584
 585 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
 586 export MODLIB
 587
 588 #
 589 #  INSTALL_MOD_STRIP, if defined, will cause modules to be
 590 #  stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
 591 #  the default option --strip-debug will be used.  Otherwise,
 592 #  INSTALL_MOD_STRIP will used as the options to the strip command.
 593
 594 ifdef INSTALL_MOD_STRIP
 595 ifeq ($(INSTALL_MOD_STRIP),1)
 596 mod_strip_cmd = $(STRIP) --strip-debug
 597 else
 598 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
 599 endif # INSTALL_MOD_STRIP=1
 600 else
 601 mod_strip_cmd = true
 602 endif # INSTALL_MOD_STRIP
 603 export mod_strip_cmd
 604
 605
 606 ifeq ($(KBUILD_EXTMOD),)
 607 core-y          += kernel/ mm/ fs/ ipc/ security/ crypto/ block/
 608
 609 vmlinux-dirs    := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
 610                      $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
 611                      $(net-y) $(net-m) $(libs-y) $(libs-m)))
 612
 613 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
 614                      $(init-n) $(init-) \
 615                      $(core-n) $(core-) $(drivers-n) $(drivers-) \
 616                      $(net-n)  $(net-)  $(libs-n)    $(libs-))))
 617
 618 init-y          := $(patsubst %/, %/built-in.o, $(init-y))
 619 core-y          := $(patsubst %/, %/built-in.o, $(core-y))
 620 drivers-y       := $(patsubst %/, %/built-in.o, $(drivers-y))
 621 net-y           := $(patsubst %/, %/built-in.o, $(net-y))
 622 libs-y1         := $(patsubst %/, %/lib.a, $(libs-y))
 623 libs-y2         := $(patsubst %/, %/built-in.o, $(libs-y))
 624 libs-y          := $(libs-y1) $(libs-y2)
 625
 626 # Build vmlinux
 627 # ---------------------------------------------------------------------------
 628 # vmlinux is built from the objects selected by $(vmlinux-init) and
 629 # $(vmlinux-main). Most are built-in.o files from top-level directories
 630 # in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
 631 # Ordering when linking is important, and $(vmlinux-init) must be first.
 632 #
 633 # vmlinux
 634 #   ^
 635 #   |
 636 #   +-< $(vmlinux-init)
 637 #   |   +--< init/version.o + more
 638 #   |
 639 #   +--< $(vmlinux-main)
 640 #   |    +--< driver/built-in.o mm/built-in.o + more
 641 #   |
 642 #   +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
 643 #
 644 # vmlinux version (uname -v) cannot be updated during normal
 645 # descending-into-subdirs phase since we do not yet know if we need to
 646 # update vmlinux.
 647 # Therefore this step is delayed until just before final link of vmlinux -
 648 # except in the kallsyms case where it is done just before adding the
 649 # symbols to the kernel.
 650 #
 651 # System.map is generated to document addresses of all kernel symbols
 652
 653 vmlinux-init := $(head-y) $(init-y)
 654 vmlinux-main := $(core-y) $(libs-y) $(drivers-y) $(net-y)
 655 vmlinux-all  := $(vmlinux-init) $(vmlinux-main)
 656 vmlinux-lds  := arch/$(SRCARCH)/kernel/vmlinux.lds
 657 export KBUILD_VMLINUX_OBJS := $(vmlinux-all)
 658
 659 # Rule to link vmlinux - also used during CONFIG_KALLSYMS
 660 # May be overridden by arch/$(ARCH)/Makefile
 661 quiet_cmd_vmlinux__ ?= LD      $@
 662       cmd_vmlinux__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) -o $@ \
 663       -T $(vmlinux-lds) $(vmlinux-init)                          \
 664       --start-group $(vmlinux-main) --end-group                  \
 665       $(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o FORCE ,$^)
 666
 667 # Generate new vmlinux version
 668 quiet_cmd_vmlinux_version = GEN     .version
 669       cmd_vmlinux_version = set -e;                     \
 670         if [ ! -r .version ]; then                      \
 671           rm -f .version;                               \
 672           echo 1 >.version;                             \
 673         else                                            \
 674           mv .version .old_version;                     \
 675           expr 0$$(cat .old_version) + 1 >.version;     \
 676         fi;                                             \
 677         $(MAKE) $(build)=init
 678
 679 # Generate System.map
 680 quiet_cmd_sysmap = SYSMAP
 681       cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap
 682
 683 # Link of vmlinux
 684 # If CONFIG_KALLSYMS is set .version is already updated
 685 # Generate System.map and verify that the content is consistent
 686 # Use + in front of the vmlinux_version rule to silent warning with make -j2
 687 # First command is ':' to allow us to use + in front of the rule
 688 define rule_vmlinux__
 689         :
 690         $(if $(CONFIG_KALLSYMS),,+$(call cmd,vmlinux_version))
 691
 692         $(call cmd,vmlinux__)
 693         $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
 694
 695         $(Q)$(if $($(quiet)cmd_sysmap),                                      \
 696           echo '  $($(quiet)cmd_sysmap)  System.map' &&)                     \
 697         $(cmd_sysmap) $@ System.map;                                         \
 698         if [ $$? -ne 0 ]; then                                               \
 699                 rm -f $@;                                                    \
 700                 /bin/false;                                                  \
 701         fi;
 702         $(verify_kallsyms)
 703 endef
 704
 705
 706 ifdef CONFIG_KALLSYMS
 707 # Generate section listing all symbols and add it into vmlinux $(kallsyms.o)
 708 # It's a three stage process:
 709 # o .tmp_vmlinux1 has all symbols and sections, but __kallsyms is
 710 #   empty
 711 #   Running kallsyms on that gives us .tmp_kallsyms1.o with
 712 #   the right size - vmlinux version (uname -v) is updated during this step
 713 # o .tmp_vmlinux2 now has a __kallsyms section of the right size,
 714 #   but due to the added section, some addresses have shifted.
 715 #   From here, we generate a correct .tmp_kallsyms2.o
 716 # o The correct .tmp_kallsyms2.o is linked into the final vmlinux.
 717 # o Verify that the System.map from vmlinux matches the map from
 718 #   .tmp_vmlinux2, just in case we did not generate kallsyms correctly.
 719 # o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
 720 #   .tmp_vmlinux3 and .tmp_kallsyms3.o.  This is only meant as a
 721 #   temporary bypass to allow the kernel to be built while the
 722 #   maintainers work out what went wrong with kallsyms.
 723
 724 ifdef CONFIG_KALLSYMS_EXTRA_PASS
 725 last_kallsyms := 3
 726 else
 727 last_kallsyms := 2
 728 endif
 729
 730 kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
 731
 732 define verify_kallsyms
 733         $(Q)$(if $($(quiet)cmd_sysmap),                                      \
 734           echo '  $($(quiet)cmd_sysmap)  .tmp_System.map' &&)                \
 735           $(cmd_sysmap) .tmp_vmlinux$(last_kallsyms) .tmp_System.map
 736         $(Q)cmp -s System.map .tmp_System.map ||                             \
 737                 (echo Inconsistent kallsyms data;                            \
 738                  echo Try setting CONFIG_KALLSYMS_EXTRA_PASS;                \
 739                  rm .tmp_kallsyms* ; /bin/false )
 740 endef
 741
 742 # Update vmlinux version before link
 743 # Use + in front of this rule to silent warning about make -j1
 744 # First command is ':' to allow us to use + in front of this rule
 745 cmd_ksym_ld = $(cmd_vmlinux__)
 746 define rule_ksym_ld
 747         :
 748         +$(call cmd,vmlinux_version)
 749         $(call cmd,vmlinux__)
 750         $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
 751 endef
 752
 753 # Generate .S file with all kernel symbols
 754 quiet_cmd_kallsyms = KSYM    $@
 755       cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
 756                      $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
 757
 758 .tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
 759         $(call if_changed_dep,as_o_S)
 760
 761 .tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
 762         $(call cmd,kallsyms)
 763
 764 # .tmp_vmlinux1 must be complete except kallsyms, so update vmlinux version
 765 .tmp_vmlinux1: $(vmlinux-lds) $(vmlinux-all) FORCE
 766         $(call if_changed_rule,ksym_ld)
 767
 768 .tmp_vmlinux2: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms1.o FORCE
 769         $(call if_changed,vmlinux__)
 770
 771 .tmp_vmlinux3: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms2.o FORCE
 772         $(call if_changed,vmlinux__)
 773
 774 # Needs to visit scripts/ before $(KALLSYMS) can be used.
 775 $(KALLSYMS): scripts ;
 776
 777 # Generate some data for debugging strange kallsyms problems
 778 debug_kallsyms: .tmp_map$(last_kallsyms)
 779
 780 .tmp_map%: .tmp_vmlinux% FORCE
 781         ($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@
 782
 783 .tmp_map3: .tmp_map2
 784
 785 .tmp_map2: .tmp_map1
 786
 787 endif # ifdef CONFIG_KALLSYMS
 788
 789 # Do modpost on a prelinked vmlinux. The finally linked vmlinux has
 790 # relevant sections renamed as per the linker script.
 791 quiet_cmd_vmlinux-modpost = LD      $@
 792       cmd_vmlinux-modpost = $(LD) $(LDFLAGS) -r -o $@                          \
 793          $(vmlinux-init) --start-group $(vmlinux-main) --end-group             \
 794          $(filter-out $(vmlinux-init) $(vmlinux-main) $(vmlinux-lds) FORCE ,$^)
 795 define rule_vmlinux-modpost
 796         :
 797         +$(call cmd,vmlinux-modpost)
 798         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $@
 799         $(Q)echo 'cmd_$@ := $(cmd_vmlinux-modpost)' > $(dot-target).cmd
 800 endef
 801
 802 # vmlinux image - including updated kernel symbols
 803 vmlinux: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o $(kallsyms.o) FORCE
 804 ifdef CONFIG_HEADERS_CHECK
 805         $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
 806 endif
 807 ifdef CONFIG_SAMPLES
 808         $(Q)$(MAKE) $(build)=samples
 809 endif
 810         $(call vmlinux-modpost)
 811         $(call if_changed_rule,vmlinux__)
 812         $(Q)rm -f .old_version
 813
 814 # build vmlinux.o first to catch section mismatch errors early
 815 ifdef CONFIG_KALLSYMS
 816 .tmp_vmlinux1: vmlinux.o
 817 endif
 818 vmlinux.o: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) FORCE
 819         $(call if_changed_rule,vmlinux-modpost)
 820
 821 # The actual objects are generated when descending,
 822 # make sure no implicit rule kicks in
 823 $(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(vmlinux-dirs) ;
 824
 825 # Handle descending into subdirectories listed in $(vmlinux-dirs)
 826 # Preset locale variables to speed up the build process. Limit locale
 827 # tweaks to this spot to avoid wrong language settings when running
 828 # make menuconfig etc.
 829 # Error messages still appears in the original language
 830
 831 PHONY += $(vmlinux-dirs)
 832 $(vmlinux-dirs): prepare scripts
 833         $(Q)$(MAKE) $(build)=$@
 834
 835 # Build the kernel release string
 836 #
 837 # The KERNELRELEASE value built here is stored in the file
 838 # include/config/kernel.release, and is used when executing several
 839 # make targets, such as "make install" or "make modules_install."
 840 #
 841 # The eventual kernel release string consists of the following fields,
 842 # shown in a hierarchical format to show how smaller parts are concatenated
 843 # to form the larger and final value, with values coming from places like
 844 # the Makefile, kernel config options, make command line options and/or
 845 # SCM tag information.
 846 #
 847 #       $(KERNELVERSION)
 848 #         $(VERSION)                    eg, 2
 849 #         $(PATCHLEVEL)                 eg, 6
 850 #         $(SUBLEVEL)                   eg, 18
 851 #         $(EXTRAVERSION)               eg, -rc6
 852 #       $(localver-full)
 853 #         $(localver)
 854 #           localversion*               (files without backups, containing '~')
 855 #           $(CONFIG_LOCALVERSION)      (from kernel config setting)
 856 #         $(localver-auto)              (only if CONFIG_LOCALVERSION_AUTO is set)
 857 #           ./scripts/setlocalversion   (SCM tag, if one exists)
 858 #           $(LOCALVERSION)             (from make command line if provided)
 859 #
 860 #  Note how the final $(localver-auto) string is included *only* if the
 861 # kernel config option CONFIG_LOCALVERSION_AUTO is selected.  Also, at the
 862 # moment, only git is supported but other SCMs can edit the script
 863 # scripts/setlocalversion and add the appropriate checks as needed.
 864
 865 pattern = ".*/localversion[^~]*"
 866 string  = $(shell cat /dev/null \
 867            `find $(objtree) $(srctree) -maxdepth 1 -regex $(pattern) | sort -u`)
 868
 869 localver = $(subst $(space),, $(string) \
 870                               $(patsubst "%",%,$(CONFIG_LOCALVERSION)))
 871
 872 # If CONFIG_LOCALVERSION_AUTO is set scripts/setlocalversion is called
 873 # and if the SCM is know a tag from the SCM is appended.
 874 # The appended tag is determined by the SCM used.
 875 #
 876 # Currently, only git is supported.
 877 # Other SCMs can edit scripts/setlocalversion and add the appropriate
 878 # checks as needed.
 879 ifdef CONFIG_LOCALVERSION_AUTO
 880         _localver-auto = $(shell $(CONFIG_SHELL) \
 881                           $(srctree)/scripts/setlocalversion $(srctree))
 882         localver-auto  = $(LOCALVERSION)$(_localver-auto)
 883 endif
 884
 885 localver-full = $(localver)$(localver-auto)
 886
 887 # Store (new) KERNELRELASE string in include/config/kernel.release
 888 kernelrelease = $(KERNELVERSION)$(localver-full)
 889 include/config/kernel.release: include/config/auto.conf FORCE
 890         $(Q)rm -f $@
 891         $(Q)echo $(kernelrelease) > $@
 892
 893
 894 # Things we need to do before we recursively start building the kernel
 895 # or the modules are listed in "prepare".
 896 # A multi level approach is used. prepareN is processed before prepareN-1.
 897 # archprepare is used in arch Makefiles and when processed asm symlink,
 898 # version.h and scripts_basic is processed / created.
 899
 900 # Listed in dependency order
 901 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
 902
 903 # prepare3 is used to check if we are building in a separate output directory,
 904 # and if so do:
 905 # 1) Check that make has not been executed in the kernel src $(srctree)
 906 # 2) Create the include2 directory, used for the second asm symlink
 907 prepare3: include/config/kernel.release
 908 ifneq ($(KBUILD_SRC),)
 909         @echo '  Using $(srctree) as source for kernel'
 910         $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
 911                 echo "  $(srctree) is not clean, please run 'make mrproper'";\
 912                 echo "  in the '$(srctree)' directory.";\
 913                 /bin/false; \
 914         fi;
 915         $(Q)if [ ! -d include2 ]; then mkdir -p include2; fi;
 916         $(Q)ln -fsn $(srctree)/include/asm-$(SRCARCH) include2/asm
 917 endif
 918
 919 # prepare2 creates a makefile if using a separate output directory
 920 prepare2: prepare3 outputmakefile
 921
 922 prepare1: prepare2 include/linux/version.h include/linux/utsrelease.h \
 923                    include/asm include/config/auto.conf
 924         $(cmd_crmodverdir)
 925
 926 archprepare: prepare1 scripts_basic
 927
 928 prepare0: archprepare FORCE
 929         $(Q)$(MAKE) $(build)=.
 930         $(Q)$(MAKE) $(build)=. missing-syscalls
 931
 932 # All the preparing..
 933 prepare: prepare0
 934
 935 # Leave this as default for preprocessing vmlinux.lds.S, which is now
 936 # done in arch/$(ARCH)/kernel/Makefile
 937
 938 export CPPFLAGS_vmlinux.lds += -P -C -U$(ARCH)
 939
 940 # The asm symlink changes when $(ARCH) changes.
 941 # Detect this and ask user to run make mrproper
 942
 943 include/asm: FORCE
 944         $(Q)set -e; asmlink=`readlink include/asm | cut -d '-' -f 2`;   \
 945         if [ -L include/asm ]; then                                     \
 946                 if [ "$$asmlink" != "$(SRCARCH)" ]; then                \
 947                         echo "ERROR: the symlink $@ points to asm-$$asmlink but asm-$(SRCARCH) was expected"; \
 948                         echo "       set ARCH or save .config and run 'make mrproper' to fix it";             \
 949                         exit 1;                                         \
 950                 fi;                                                     \
 951         else                                                            \
 952                 echo '  SYMLINK $@ -> include/asm-$(SRCARCH)';          \
 953                 if [ ! -d include ]; then                               \
 954                         mkdir -p include;                               \
 955                 fi;                                                     \
 956                 ln -fsn asm-$(SRCARCH) $@;                              \
 957         fi
 958
 959 # Generate some files
 960 # ---------------------------------------------------------------------------
 961
 962 # KERNELRELEASE can change from a few different places, meaning version.h
 963 # needs to be updated, so this check is forced on all builds
 964
 965 uts_len := 64
 966 define filechk_utsrelease.h
 967         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
 968           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
 969           exit 1;                                                         \
 970         fi;                                                               \
 971         (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
 972 endef
 973
 974 define filechk_version.h
 975         (echo \#define LINUX_VERSION_CODE $(shell                             \
 976         expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL));     \
 977         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
 978 endef
 979
 980 include/linux/version.h: $(srctree)/Makefile FORCE
 981         $(call filechk,version.h)
 982
 983 include/linux/utsrelease.h: include/config/kernel.release FORCE
 984         $(call filechk,utsrelease.h)
 985
 986 # ---------------------------------------------------------------------------
 987
 988 PHONY += depend dep
 989 depend dep:
 990         @echo '*** Warning: make $@ is unnecessary now.'
 991
 992 # ---------------------------------------------------------------------------
 993 # Kernel headers
 994 INSTALL_HDR_PATH=$(objtree)/usr
 995 export INSTALL_HDR_PATH
 996
 997 HDRFILTER=generic i386 x86_64
 998 HDRARCHES=$(filter-out $(HDRFILTER),$(patsubst $(srctree)/include/asm-%/Kbuild,%,$(wildcard $(srctree)/include/asm-*/Kbuild)))
 999
1000 PHONY += headers_install_all
1001 headers_install_all: include/linux/version.h scripts_basic FORCE
1002         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1003         $(Q)for arch in $(HDRARCHES); do \
1004          $(MAKE) ARCH=$$arch -f $(srctree)/scripts/Makefile.headersinst obj=include BIASMDIR=-bi-$$arch ;\
1005          done
1006
1007 PHONY += headers_install
1008 headers_install: include/linux/version.h scripts_basic FORCE
1009         @if [ ! -r $(srctree)/include/asm-$(SRCARCH)/Kbuild ]; then \
1010           echo '*** Error: Headers not exportable for this architecture ($(SRCARCH))'; \
1011           exit 1 ; fi
1012         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1013         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.headersinst ARCH=$(SRCARCH) obj=include
1014
1015 PHONY += headers_check_all
1016 headers_check_all: headers_install_all
1017         $(Q)for arch in $(HDRARCHES); do \
1018          $(MAKE) ARCH=$$arch -f $(srctree)/scripts/Makefile.headersinst obj=include BIASMDIR=-bi-$$arch HDRCHECK=1 ;\
1019          done
1020
1021 PHONY += headers_check
1022 headers_check: headers_install
1023         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.headersinst ARCH=$(SRCARCH) obj=include HDRCHECK=1
1024
1025 # ---------------------------------------------------------------------------
1026 # Modules
1027
1028 ifdef CONFIG_MODULES
1029
1030 # By default, build modules as well
1031
1032 all: modules
1033
1034 #       Build modules
1035 #
1036 #       A module can be listed more than once in obj-m resulting in
1037 #       duplicate lines in modules.order files.  Those are removed
1038 #       using awk while concatenating to the final file.
1039
1040 PHONY += modules
1041 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux)
1042         $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1043         @echo '  Building modules, stage 2.';
1044         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1045
1046
1047 # Target to prepare building external modules
1048 PHONY += modules_prepare
1049 modules_prepare: prepare scripts
1050
1051 # Target to install modules
1052 PHONY += modules_install
1053 modules_install: _modinst_ _modinst_post
1054
1055 PHONY += _modinst_
1056 _modinst_:
1057         @if [ -z "`$(DEPMOD) -V 2>/dev/null | grep module-init-tools`" ]; then \
1058                 echo "Warning: you may need to install module-init-tools"; \
1059                 echo "See http://www.codemonkey.org.uk/docs/post-halloween-2.6.txt";\
1060                 sleep 1; \
1061         fi
1062         @rm -rf $(MODLIB)/kernel
1063         @rm -f $(MODLIB)/source
1064         @mkdir -p $(MODLIB)/kernel
1065         @ln -s $(srctree) $(MODLIB)/source
1066         @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1067                 rm -f $(MODLIB)/build ; \
1068                 ln -s $(objtree) $(MODLIB)/build ; \
1069         fi
1070         @cp -f $(objtree)/modules.order $(MODLIB)/
1071         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1072
1073 # This depmod is only for convenience to give the initial
1074 # boot a modules.dep even before / is mounted read-write.  However the
1075 # boot script depmod is the master version.
1076 PHONY += _modinst_post
1077 _modinst_post: _modinst_
1078         $(call cmd,depmod)
1079
1080 else # CONFIG_MODULES
1081
1082 # Modules not configured
1083 # ---------------------------------------------------------------------------
1084
1085 modules modules_install: FORCE
1086         @echo
1087         @echo "The present kernel configuration has modules disabled."
1088         @echo "Type 'make config' and enable loadable module support."
1089         @echo "Then build a kernel with module support enabled."
1090         @echo
1091         @exit 1
1092
1093 endif # CONFIG_MODULES
1094
1095 ###
1096 # Cleaning is done on three levels.
1097 # make clean     Delete most generated files
1098 #                Leave enough to build external modules
1099 # make mrproper  Delete the current configuration, and all generated files
1100 # make distclean Remove editor backup files, patch leftover files and the like
1101
1102 # Directories & files removed with 'make clean'
1103 CLEAN_DIRS  += $(MODVERDIR)
1104 CLEAN_FILES +=  vmlinux System.map \
1105                 .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map
1106
1107 # Directories & files removed with 'make mrproper'
1108 MRPROPER_DIRS  += include/config include2 usr/include
1109 MRPROPER_FILES += .config .config.old include/asm .version .old_version \
1110                   include/linux/autoconf.h include/linux/version.h      \
1111                   include/linux/utsrelease.h                            \
1112                   Module.symvers tags TAGS cscope*
1113
1114 # clean - Delete most, but leave enough to build external modules
1115 #
1116 clean: rm-dirs  := $(CLEAN_DIRS)
1117 clean: rm-files := $(CLEAN_FILES)
1118 clean-dirs      := $(addprefix _clean_,$(srctree) $(vmlinux-alldirs))
1119
1120 PHONY += $(clean-dirs) clean archclean
1121 $(clean-dirs):
1122         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1123
1124 clean: archclean $(clean-dirs)
1125         $(call cmd,rmdirs)
1126         $(call cmd,rmfiles)
1127         @find . $(RCS_FIND_IGNORE) \
1128                 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1129                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1130                 -o -name '*.symtypes' -o -name 'modules.order' \) \
1131                 -type f -print | xargs rm -f
1132
1133 # mrproper - Delete all generated files, including .config
1134 #
1135 mrproper: rm-dirs  := $(wildcard $(MRPROPER_DIRS))
1136 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1137 mrproper-dirs      := $(addprefix _mrproper_,Documentation/DocBook scripts)
1138
1139 PHONY += $(mrproper-dirs) mrproper archmrproper
1140 $(mrproper-dirs):
1141         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1142
1143 mrproper: clean archmrproper $(mrproper-dirs)
1144         $(call cmd,rmdirs)
1145         $(call cmd,rmfiles)
1146
1147 # distclean
1148 #
1149 PHONY += distclean
1150
1151 distclean: mrproper
1152         @find $(srctree) $(RCS_FIND_IGNORE) \
1153                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1154                 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1155                 -o -name '.*.rej' -o -size 0 \
1156                 -o -name '*%' -o -name '.*.cmd' -o -name 'core' \) \
1157                 -type f -print | xargs rm -f
1158
1159
1160 # Packaging of the kernel to various formats
1161 # ---------------------------------------------------------------------------
1162 # rpm target kept for backward compatibility
1163 package-dir     := $(srctree)/scripts/package
1164
1165 %pkg: include/config/kernel.release FORCE
1166         $(Q)$(MAKE) $(build)=$(package-dir) $@
1167 rpm: include/config/kernel.release FORCE
1168         $(Q)$(MAKE) $(build)=$(package-dir) $@
1169
1170
1171 # Brief documentation of the typical targets used
1172 # ---------------------------------------------------------------------------
1173
1174 boards := $(wildcard $(srctree)/arch/$(ARCH)/configs/*_defconfig)
1175 boards := $(notdir $(boards))
1176
1177 help:
1178         @echo  'Cleaning targets:'
1179         @echo  '  clean           - Remove most generated files but keep the config and'
1180         @echo  '                    enough build support to build external modules'
1181         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1182         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1183         @echo  ''
1184         @echo  'Configuration targets:'
1185         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1186         @echo  ''
1187         @echo  'Other generic targets:'
1188         @echo  '  all             - Build all targets marked with [*]'
1189         @echo  '* vmlinux         - Build the bare kernel'
1190         @echo  '* modules         - Build all modules'
1191         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1192         @echo  '  dir/            - Build all files in dir and below'
1193         @echo  '  dir/file.[ois]  - Build specified target only'
1194         @echo  '  dir/file.ko     - Build module including final link'
1195         @echo  '  prepare         - Set up for building external modules'
1196         @echo  '  tags/TAGS       - Generate tags file for editors'
1197         @echo  '  cscope          - Generate cscope index'
1198         @echo  '  kernelrelease   - Output the release version string'
1199         @echo  '  kernelversion   - Output the version stored in Makefile'
1200         @if [ -r $(srctree)/include/asm-$(SRCARCH)/Kbuild ]; then \
1201          echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1202          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1203          fi
1204         @echo  ''
1205         @echo  'Static analysers'
1206         @echo  '  checkstack      - Generate a list of stack hogs'
1207         @echo  '  namespacecheck  - Name space analysis on compiled kernel'
1208         @echo  '  versioncheck    - Sanity check on version.h usage'
1209         @echo  '  includecheck    - Check for duplicate included header files'
1210         @echo  '  export_report   - List the usages of all exported symbols'
1211         @if [ -r $(srctree)/include/asm-$(SRCARCH)/Kbuild ]; then \
1212          echo  '  headers_check   - Sanity check on exported headers'; \
1213          fi
1214         @echo  ''
1215         @echo  'Kernel packaging:'
1216         @$(MAKE) $(build)=$(package-dir) help
1217         @echo  ''
1218         @echo  'Documentation targets:'
1219         @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1220         @echo  ''
1221         @echo  'Architecture specific targets ($(ARCH)):'
1222         @$(if $(archhelp),$(archhelp),\
1223                 echo '  No architecture specific help defined for $(ARCH)')
1224         @echo  ''
1225         @$(if $(boards), \
1226                 $(foreach b, $(boards), \
1227                 printf "  %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1228                 echo '')
1229
1230         @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1231         @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1232         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1233         @echo  '  make C=1   [targets] Check all c source with $$CHECK (sparse by default)'
1234         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1235         @echo  ''
1236         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1237         @echo  'For further info see the ./README file'
1238
1239
1240 # Documentation targets
1241 # ---------------------------------------------------------------------------
1242 %docs: scripts_basic FORCE
1243         $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1244
1245 else # KBUILD_EXTMOD
1246
1247 ###
1248 # External module support.
1249 # When building external modules the kernel used as basis is considered
1250 # read-only, and no consistency checks are made and the make
1251 # system is not used on the basis kernel. If updates are required
1252 # in the basis kernel ordinary make commands (without M=...) must
1253 # be used.
1254 #
1255 # The following are the only valid targets when building external
1256 # modules.
1257 # make M=dir clean     Delete all automatically generated files
1258 # make M=dir modules   Make all modules in specified dir
1259 # make M=dir           Same as 'make M=dir modules'
1260 # make M=dir modules_install
1261 #                      Install the modules built in the module directory
1262 #                      Assumes install directory is already created
1263
1264 # We are always building modules
1265 KBUILD_MODULES := 1
1266 PHONY += crmodverdir
1267 crmodverdir:
1268         $(cmd_crmodverdir)
1269
1270 PHONY += $(objtree)/Module.symvers
1271 $(objtree)/Module.symvers:
1272         @test -e $(objtree)/Module.symvers || ( \
1273         echo; \
1274         echo "  WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1275         echo "           is missing; modules will have no dependencies and modversions."; \
1276         echo )
1277
1278 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1279 PHONY += $(module-dirs) modules
1280 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1281         $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1282
1283 modules: $(module-dirs)
1284         @echo '  Building modules, stage 2.';
1285         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1286
1287 PHONY += modules_install
1288 modules_install: _emodinst_ _emodinst_post
1289
1290 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1291 PHONY += _emodinst_
1292 _emodinst_:
1293         $(Q)mkdir -p $(MODLIB)/$(install-dir)
1294         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1295
1296 PHONY += _emodinst_post
1297 _emodinst_post: _emodinst_
1298         $(call cmd,depmod)
1299
1300 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1301
1302 PHONY += $(clean-dirs) clean
1303 $(clean-dirs):
1304         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1305
1306 clean:  rm-dirs := $(MODVERDIR)
1307 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1308 clean: $(clean-dirs)
1309         $(call cmd,rmdirs)
1310         $(call cmd,rmfiles)
1311         @find $(KBUILD_EXTMOD) $(RCS_FIND_IGNORE) \
1312                 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1313                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
1314                 -type f -print | xargs rm -f
1315
1316 help:
1317         @echo  '  Building external modules.'
1318         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1319         @echo  ''
1320         @echo  '  modules         - default target, build the module(s)'
1321         @echo  '  modules_install - install the module'
1322         @echo  '  clean           - remove generated files in module directory only'
1323         @echo  ''
1324
1325 # Dummies...
1326 PHONY += prepare scripts
1327 prepare: ;
1328 scripts: ;
1329 endif # KBUILD_EXTMOD
1330
1331 # Generate tags for editors
1332 # ---------------------------------------------------------------------------
1333
1334 #We want __srctree to totally vanish out when KBUILD_OUTPUT is not set
1335 #(which is the most common case IMHO) to avoid unneeded clutter in the big tags file.
1336 #Adding $(srctree) adds about 20M on i386 to the size of the output file!
1337
1338 ifeq ($(src),$(obj))
1339 __srctree =
1340 else
1341 __srctree = $(srctree)/
1342 endif
1343
1344 ifeq ($(ALLSOURCE_ARCHS),)
1345 ifeq ($(ARCH),um)
1346 ALLINCLUDE_ARCHS := $(ARCH) $(SUBARCH)
1347 else
1348 ALLINCLUDE_ARCHS := $(SRCARCH)
1349 endif
1350 else
1351 #Allow user to specify only ALLSOURCE_PATHS on the command line, keeping existing behaviour.
1352 ALLINCLUDE_ARCHS := $(ALLSOURCE_ARCHS)
1353 endif
1354
1355 ALLSOURCE_ARCHS := $(SRCARCH)
1356
1357 define find-sources
1358         ( for arch in $(ALLSOURCE_ARCHS) ; do \
1359                find $(__srctree)arch/$${arch} $(RCS_FIND_IGNORE) \
1360                     -name $1 -print; \
1361           done ; \
1362           find $(__srctree)security/selinux/include $(RCS_FIND_IGNORE) \
1363                -name $1 -print; \
1364           find $(__srctree)include $(RCS_FIND_IGNORE) \
1365                \( -name config -o -name 'asm-*' \) -prune \
1366                -o -name $1 -print; \
1367           for arch in $(ALLINCLUDE_ARCHS) ; do \
1368                find $(__srctree)include/asm-$${arch} $(RCS_FIND_IGNORE) \
1369                     -name $1 -print; \
1370           done ; \
1371           find $(__srctree)include/asm-generic $(RCS_FIND_IGNORE) \
1372                -name $1 -print; \
1373           find $(__srctree) $(RCS_FIND_IGNORE) \
1374                \( -name include -o -name arch -o -name '.tmp_*' \) -prune -o \
1375                -name $1 -print; \
1376           )
1377 endef
1378
1379 define all-sources
1380         $(call find-sources,'*.[chS]')
1381 endef
1382 define all-kconfigs
1383         $(call find-sources,'Kconfig*')
1384 endef
1385 define all-defconfigs
1386         $(call find-sources,'defconfig')
1387 endef
1388
1389 define xtags
1390         if $1 --version 2>&1 | grep -iq exuberant; then \
1391             $(all-sources) | xargs $1 -a \
1392                 -I __initdata,__exitdata,__acquires,__releases \
1393                 -I __read_mostly,____cacheline_aligned,____cacheline_aligned_in_smp,____cacheline_internodealigned_in_smp \
1394                 -I EXPORT_SYMBOL,EXPORT_SYMBOL_GPL \
1395                 --extra=+f --c-kinds=+px \
1396                 --regex-asm='/^ENTRY\(([^)]*)\).*/\1/'; \
1397             $(all-kconfigs) | xargs $1 -a \
1398                 --langdef=kconfig \
1399                 --language-force=kconfig \
1400                 --regex-kconfig='/^[[:blank:]]*config[[:blank:]]+([[:alnum:]_]+)/\1/'; \
1401             $(all-defconfigs) | xargs -r $1 -a \
1402                 --langdef=dotconfig \
1403                 --language-force=dotconfig \
1404                 --regex-dotconfig='/^#?[[:blank:]]*(CONFIG_[[:alnum:]_]+)/\1/'; \
1405         elif $1 --version 2>&1 | grep -iq emacs; then \
1406             $(all-sources) | xargs $1 -a; \
1407             $(all-kconfigs) | xargs $1 -a \
1408                 --regex='/^[ \t]*config[ \t]+\([a-zA-Z0-9_]+\)/\1/'; \
1409             $(all-defconfigs) | xargs -r $1 -a \
1410                 --regex='/^#?[ \t]?\(CONFIG_[a-zA-Z0-9_]+\)/\1/'; \
1411         else \
1412             $(all-sources) | xargs $1 -a; \
1413         fi
1414 endef
1415
1416 quiet_cmd_cscope-file = FILELST cscope.files
1417       cmd_cscope-file = (echo \-k; echo \-q; $(all-sources)) > cscope.files
1418
1419 quiet_cmd_cscope = MAKE    cscope.out
1420       cmd_cscope = cscope -b
1421
1422 cscope: FORCE
1423         $(call cmd,cscope-file)
1424         $(call cmd,cscope)
1425
1426 quiet_cmd_TAGS = MAKE   $@
1427 define cmd_TAGS
1428         rm -f $@; \
1429         $(call xtags,etags)
1430 endef
1431
1432 TAGS: FORCE
1433         $(call cmd,TAGS)
1434
1435 quiet_cmd_tags = MAKE   $@
1436 define cmd_tags
1437         rm -f $@; \
1438         $(call xtags,ctags)
1439 endef
1440
1441 tags: FORCE
1442         $(call cmd,tags)
1443
1444
1445 # Scripts to check various things for consistency
1446 # ---------------------------------------------------------------------------
1447
1448 includecheck:
1449         find * $(RCS_FIND_IGNORE) \
1450                 -name '*.[hcS]' -type f -print | sort \
1451                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1452
1453 versioncheck:
1454         find * $(RCS_FIND_IGNORE) \
1455                 -name '*.[hcS]' -type f -print | sort \
1456                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1457
1458 namespacecheck:
1459         $(PERL) $(srctree)/scripts/namespace.pl
1460
1461 export_report:
1462         $(PERL) $(srctree)/scripts/export_report.pl
1463
1464 endif #ifeq ($(config-targets),1)
1465 endif #ifeq ($(mixed-targets),1)
1466
1467 PHONY += checkstack kernelrelease kernelversion
1468
1469 # UML needs a little special treatment here.  It wants to use the host
1470 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1471 # else wants $(ARCH), including people doing cross-builds, which means
1472 # that $(SUBARCH) doesn't work here.
1473 ifeq ($(ARCH), um)
1474 CHECKSTACK_ARCH := $(SUBARCH)
1475 else
1476 CHECKSTACK_ARCH := $(ARCH)
1477 endif
1478 checkstack:
1479         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1480         $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1481
1482 kernelrelease:
1483         $(if $(wildcard include/config/kernel.release), $(Q)echo $(KERNELRELEASE), \
1484         $(error kernelrelease not valid - run 'make prepare' to update it))
1485 kernelversion:
1486         @echo $(KERNELVERSION)
1487
1488 # Single targets
1489 # ---------------------------------------------------------------------------
1490 # Single targets are compatible with:
1491 # - build with mixed source and output
1492 # - build with separate output dir 'make O=...'
1493 # - external modules
1494 #
1495 #  target-dir => where to store outputfile
1496 #  build-dir  => directory in kernel source tree to use
1497
1498 ifeq ($(KBUILD_EXTMOD),)
1499         build-dir  = $(patsubst %/,%,$(dir $@))
1500         target-dir = $(dir $@)
1501 else
1502         zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1503         build-dir  = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1504         target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1505 endif
1506
1507 %.s: %.c prepare scripts FORCE
1508         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1509 %.i: %.c prepare scripts FORCE
1510         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1511 %.o: %.c prepare scripts FORCE
1512         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1513 %.lst: %.c prepare scripts FORCE
1514         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1515 %.s: %.S prepare scripts FORCE
1516         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1517 %.o: %.S prepare scripts FORCE
1518         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1519 %.symtypes: %.c prepare scripts FORCE
1520         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1521
1522 # Modules
1523 / %/: prepare scripts FORCE
1524         $(cmd_crmodverdir)
1525         $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1526         $(build)=$(build-dir)
1527 %.ko: prepare scripts FORCE
1528         $(cmd_crmodverdir)
1529         $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1)   \
1530         $(build)=$(build-dir) $(@:.ko=.o)
1531         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1532
1533 # FIXME Should go into a make.lib or something
1534 # ===========================================================================
1535
1536 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN   $(wildcard $(rm-dirs)))
1537       cmd_rmdirs = rm -rf $(rm-dirs)
1538
1539 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1540       cmd_rmfiles = rm -f $(rm-files)
1541
1542 # Run depmod only is we have System.map and depmod is executable
1543 # and we build for the host arch
1544 quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1545       cmd_depmod = \
1546         if [ -r System.map -a -x $(DEPMOD) ]; then                              \
1547                 $(DEPMOD) -ae -F System.map                                     \
1548                 $(if $(strip $(INSTALL_MOD_PATH)), -b $(INSTALL_MOD_PATH) -r)   \
1549                 $(KERNELRELEASE);                                               \
1550         fi
1551
1552 # Create temporary dir for module support files
1553 # clean it up only when building all modules
1554 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1555                   $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1556
1557 a_flags = -Wp,-MD,$(depfile) $(KBUILD_AFLAGS) $(AFLAGS_KERNEL) \
1558           $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \
1559           $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(basetarget).o)
1560
1561 quiet_cmd_as_o_S = AS      $@
1562 cmd_as_o_S       = $(CC) $(a_flags) -c -o $@ $<
1563
1564 # read all saved command lines
1565
1566 targets := $(wildcard $(sort $(targets)))
1567 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1568
1569 ifneq ($(cmd_files),)
1570   $(cmd_files): ;       # Do not try to update included dependency files
1571   include $(cmd_files)
1572 endif
1573
1574 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir
1575 # Usage:
1576 # $(Q)$(MAKE) $(clean)=dir
1577 clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
1578
1579 endif   # skip-makefile
1580
1581 PHONY += FORCE
1582 FORCE:
1583
1584 # Declare the contents of the .PHONY variable as phony.  We keep that
1585 # information in a variable se we can use it in if_changed and friends.
1586 .PHONY: $(PHONY)