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Makefile

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    meto authored
    92172ea2
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    Makefile 58.92 KiB
    VERSION = 4
    PATCHLEVEL = 13
    SUBLEVEL = 0
    EXTRAVERSION =
    NAME = Fearless Coyote
    
    # *DOCUMENTATION*
    # To see a list of typical targets execute "make help"
    # More info can be located in ./README
    # Comments in this file are targeted only to the developer, do not
    # expect to learn how to build the kernel reading this file.
    
    # o Do not use make's built-in rules and variables
    #   (this increases performance and avoids hard-to-debug behaviour);
    # o Look for make include files relative to root of kernel src
    MAKEFLAGS += -rR --include-dir=$(CURDIR)
    
    # Avoid funny character set dependencies
    unexport LC_ALL
    LC_COLLATE=C
    LC_NUMERIC=C
    export LC_COLLATE LC_NUMERIC
    
    # Avoid interference with shell env settings
    unexport GREP_OPTIONS
    
    # We are using a recursive build, so we need to do a little thinking
    # to get the ordering right.
    #
    # Most importantly: sub-Makefiles should only ever modify files in
    # their own directory. If in some directory we have a dependency on
    # a file in another dir (which doesn't happen often, but it's often
    # unavoidable when linking the built-in.o targets which finally
    # turn into vmlinux), we will call a sub make in that other dir, and
    # after that we are sure that everything which is in that other dir
    # is now up to date.
    #
    # The only cases where we need to modify files which have global
    # effects are thus separated out and done before the recursive
    # descending is started. They are now explicitly listed as the
    # prepare rule.
    
    # Beautify output
    # ---------------------------------------------------------------------------
    #
    # Normally, we echo the whole command before executing it. By making
    # that echo $($(quiet)$(cmd)), we now have the possibility to set
    # $(quiet) to choose other forms of output instead, e.g.
    #
    #         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
    #         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
    #
    # If $(quiet) is empty, the whole command will be printed.
    # If it is set to "quiet_", only the short version will be printed.
    # If it is set to "silent_", nothing will be printed at all, since
    # the variable $(silent_cmd_cc_o_c) doesn't exist.
    #
    # A simple variant is to prefix commands with $(Q) - that's useful
    # for commands that shall be hidden in non-verbose mode.
    #
    #	$(Q)ln $@ :<
    #
    # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
    # If KBUILD_VERBOSE equals 1 then the above command is displayed.
    #
    # To put more focus on warnings, be less verbose as default
    # Use 'make V=1' to see the full commands
    
    ifeq ("$(origin V)", "command line")
      KBUILD_VERBOSE = $(V)
    endif
    ifndef KBUILD_VERBOSE
      KBUILD_VERBOSE = 0
    endif
    
    ifeq ($(KBUILD_VERBOSE),1)
      quiet =
      Q =
    else
      quiet=quiet_
      Q = @
    endif
    
    # If the user is running make -s (silent mode), suppress echoing of
    # commands
    
    ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
      quiet=silent_
      tools_silent=s
    endif
    
    export quiet Q KBUILD_VERBOSE
    
    # kbuild supports saving output files in a separate directory.
    # To locate output files in a separate directory two syntaxes are supported.
    # In both cases the working directory must be the root of the kernel src.
    # 1) O=
    # Use "make O=dir/to/store/output/files/"
    #
    # 2) Set KBUILD_OUTPUT
    # Set the environment variable KBUILD_OUTPUT to point to the directory
    # where the output files shall be placed.
    # export KBUILD_OUTPUT=dir/to/store/output/files/
    # make
    #
    # The O= assignment takes precedence over the KBUILD_OUTPUT environment
    # variable.
    
    # KBUILD_SRC is not intended to be used by the regular user (for now),
    # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
    ifeq ($(KBUILD_SRC),)
    
    # OK, Make called in directory where kernel src resides
    # Do we want to locate output files in a separate directory?
    ifeq ("$(origin O)", "command line")
      KBUILD_OUTPUT := $(O)
    endif
    
    # That's our default target when none is given on the command line
    PHONY := _all
    _all:
    
    # Cancel implicit rules on top Makefile
    $(CURDIR)/Makefile Makefile: ;
    
    ifneq ($(words $(subst :, ,$(CURDIR))), 1)
      $(error main directory cannot contain spaces nor colons)
    endif
    
    ifneq ($(KBUILD_OUTPUT),)
    # check that the output directory actually exists
    saved-output := $(KBUILD_OUTPUT)
    KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
    								&& /bin/pwd)
    $(if $(KBUILD_OUTPUT),, \
         $(error failed to create output directory "$(saved-output)"))
    
    PHONY += $(MAKECMDGOALS) sub-make
    
    $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
    	@:
    
    # Invoke a second make in the output directory, passing relevant variables
    sub-make:
    	$(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
    	-f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
    
    # Leave processing to above invocation of make
    skip-makefile := 1
    endif # ifneq ($(KBUILD_OUTPUT),)
    endif # ifeq ($(KBUILD_SRC),)
    
    # We process the rest of the Makefile if this is the final invocation of make
    ifeq ($(skip-makefile),)
    
    # Do not print "Entering directory ...",
    # but we want to display it when entering to the output directory
    # so that IDEs/editors are able to understand relative filenames.
    MAKEFLAGS += --no-print-directory
    
    # Call a source code checker (by default, "sparse") as part of the
    # C compilation.
    #
    # Use 'make C=1' to enable checking of only re-compiled files.
    # Use 'make C=2' to enable checking of *all* source files, regardless
    # of whether they are re-compiled or not.
    #
    # See the file "Documentation/dev-tools/sparse.rst" for more details,
    # including where to get the "sparse" utility.
    
    ifeq ("$(origin C)", "command line")
      KBUILD_CHECKSRC = $(C)
    endif
    ifndef KBUILD_CHECKSRC
      KBUILD_CHECKSRC = 0
    endif
    
    # Use make M=dir to specify directory of external module to build
    # Old syntax make ... SUBDIRS=$PWD is still supported
    # Setting the environment variable KBUILD_EXTMOD take precedence
    ifdef SUBDIRS
      KBUILD_EXTMOD ?= $(SUBDIRS)
    endif
    
    ifeq ("$(origin M)", "command line")
      KBUILD_EXTMOD := $(M)
    endif
    
    # If building an external module we do not care about the all: rule
    # but instead _all depend on modules
    PHONY += all
    ifeq ($(KBUILD_EXTMOD),)
    _all: all
    else
    _all: modules
    endif
    
    ifeq ($(KBUILD_SRC),)
            # building in the source tree
            srctree := .
    else
            ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
                    # building in a subdirectory of the source tree
                    srctree := ..
            else
                    srctree := $(KBUILD_SRC)
            endif
    endif
    objtree		:= .
    src		:= $(srctree)
    obj		:= $(objtree)
    
    VPATH		:= $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
    
    export srctree objtree VPATH
    
    # SUBARCH tells the usermode build what the underlying arch is.  That is set
    # first, and if a usermode build is happening, the "ARCH=um" on the command
    # line overrides the setting of ARCH below.  If a native build is happening,
    # then ARCH is assigned, getting whatever value it gets normally, and
    # SUBARCH is subsequently ignored.
    
    SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
    				  -e s/sun4u/sparc64/ \
    				  -e s/arm.*/arm/ -e s/sa110/arm/ \
    				  -e s/s390x/s390/ -e s/parisc64/parisc/ \
    				  -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
    				  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
    
    # Cross compiling and selecting different set of gcc/bin-utils
    # ---------------------------------------------------------------------------
    #
    # When performing cross compilation for other architectures ARCH shall be set
    # to the target architecture. (See arch/* for the possibilities).
    # ARCH can be set during invocation of make:
    # make ARCH=ia64
    # Another way is to have ARCH set in the environment.
    # The default ARCH is the host where make is executed.
    
    # CROSS_COMPILE specify the prefix used for all executables used
    # during compilation. Only gcc and related bin-utils executables
    # are prefixed with $(CROSS_COMPILE).
    # CROSS_COMPILE can be set on the command line
    # make CROSS_COMPILE=ia64-linux-
    # Alternatively CROSS_COMPILE can be set in the environment.
    # A third alternative is to store a setting in .config so that plain
    # "make" in the configured kernel build directory always uses that.
    # Default value for CROSS_COMPILE is not to prefix executables
    # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
    ARCH		?= $(SUBARCH)
    CROSS_COMPILE	?= $(CONFIG_CROSS_COMPILE:"%"=%)
    
    # Architecture as present in compile.h
    UTS_MACHINE 	:= $(ARCH)
    SRCARCH 	:= $(ARCH)
    
    # Additional ARCH settings for x86
    ifeq ($(ARCH),i386)
            SRCARCH := x86
    endif
    ifeq ($(ARCH),x86_64)
            SRCARCH := x86
    endif
    
    # Additional ARCH settings for sparc
    ifeq ($(ARCH),sparc32)
           SRCARCH := sparc
    endif
    ifeq ($(ARCH),sparc64)
           SRCARCH := sparc
    endif
    
    # Additional ARCH settings for sh
    ifeq ($(ARCH),sh64)
           SRCARCH := sh
    endif
    
    # Additional ARCH settings for tile
    ifeq ($(ARCH),tilepro)
           SRCARCH := tile
    endif
    ifeq ($(ARCH),tilegx)
           SRCARCH := tile
    endif
    
    # Where to locate arch specific headers
    hdr-arch  := $(SRCARCH)
    
    KCONFIG_CONFIG	?= .config
    export KCONFIG_CONFIG
    
    # SHELL used by kbuild
    CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
    	  else if [ -x /bin/bash ]; then echo /bin/bash; \
    	  else echo sh; fi ; fi)
    
    HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS)
    HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS)
    HOST_LFS_LIBS := $(shell getconf LFS_LIBS)
    
    HOSTCC       = gcc
    HOSTCXX      = g++
    HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
    		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS)
    HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS)
    HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS)
    HOST_LOADLIBES := $(HOST_LFS_LIBS)
    
    ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)
    HOSTCFLAGS  += -Wno-unused-value -Wno-unused-parameter \
    		-Wno-missing-field-initializers -fno-delete-null-pointer-checks
    endif
    
    # Decide whether to build built-in, modular, or both.
    # Normally, just do built-in.
    
    KBUILD_MODULES :=
    KBUILD_BUILTIN := 1
    
    # If we have only "make modules", don't compile built-in objects.
    # When we're building modules with modversions, we need to consider
    # the built-in objects during the descend as well, in order to
    # make sure the checksums are up to date before we record them.
    
    ifeq ($(MAKECMDGOALS),modules)
      KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
    endif
    
    # If we have "make <whatever> modules", compile modules
    # in addition to whatever we do anyway.
    # Just "make" or "make all" shall build modules as well
    
    ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
      KBUILD_MODULES := 1
    endif
    
    ifeq ($(MAKECMDGOALS),)
      KBUILD_MODULES := 1
    endif
    
    export KBUILD_MODULES KBUILD_BUILTIN
    export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
    
    # We need some generic definitions (do not try to remake the file).
    scripts/Kbuild.include: ;
    include scripts/Kbuild.include
    
    # Make variables (CC, etc...)
    AS		= $(CROSS_COMPILE)as
    LD		= $(CROSS_COMPILE)ld
    CC		= $(CROSS_COMPILE)gcc
    CPP		= $(CC) -E
    AR		= $(CROSS_COMPILE)ar
    NM		= $(CROSS_COMPILE)nm
    STRIP		= $(CROSS_COMPILE)strip
    OBJCOPY		= $(CROSS_COMPILE)objcopy
    OBJDUMP		= $(CROSS_COMPILE)objdump
    AWK		= awk
    GENKSYMS	= scripts/genksyms/genksyms
    INSTALLKERNEL  := installkernel
    DEPMOD		= /sbin/depmod
    PERL		= perl
    PYTHON		= python
    CHECK		= sparse
    
    CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
    		  -Wbitwise -Wno-return-void $(CF)
    NOSTDINC_FLAGS  =
    CFLAGS_MODULE   =
    AFLAGS_MODULE   =
    LDFLAGS_MODULE  =
    CFLAGS_KERNEL	=
    AFLAGS_KERNEL	=
    LDFLAGS_vmlinux =
    CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
    CFLAGS_KCOV	:= $(call cc-option,-fsanitize-coverage=trace-pc,)
    
    
    # Use USERINCLUDE when you must reference the UAPI directories only.
    USERINCLUDE    := \
    		-I$(srctree)/arch/$(hdr-arch)/include/uapi \
    		-I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
    		-I$(srctree)/include/uapi \
    		-I$(objtree)/include/generated/uapi \
                    -include $(srctree)/include/linux/kconfig.h
    
    # Use LINUXINCLUDE when you must reference the include/ directory.
    # Needed to be compatible with the O= option
    LINUXINCLUDE    := \
    		-I$(srctree)/arch/$(hdr-arch)/include \
    		-I$(objtree)/arch/$(hdr-arch)/include/generated \
    		$(if $(KBUILD_SRC), -I$(srctree)/include) \
    		-I$(objtree)/include \
    		$(USERINCLUDE)
    
    KBUILD_CPPFLAGS := -D__KERNEL__
    
    KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
    		   -fno-strict-aliasing -fno-common -fshort-wchar \
    		   -Werror-implicit-function-declaration \
    		   -Wno-format-security \
    		   -std=gnu89 $(call cc-option,-fno-PIE) \
                       -Wno-attribute-alias \
                       -Wstringop-truncation
    
    
    KBUILD_AFLAGS_KERNEL :=
    KBUILD_CFLAGS_KERNEL :=
    KBUILD_AFLAGS   := -D__ASSEMBLY__ $(call cc-option,-fno-PIE)
    KBUILD_AFLAGS_MODULE  := -DMODULE
    KBUILD_CFLAGS_MODULE  := -DMODULE
    KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
    
    # Read KERNELRELEASE from include/config/kernel.release (if it exists)
    KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
    KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
    
    export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
    export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
    export CPP AR NM STRIP OBJCOPY OBJDUMP HOSTLDFLAGS HOST_LOADLIBES
    export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
    export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
    
    export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
    export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KCOV CFLAGS_KASAN CFLAGS_UBSAN
    export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
    export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
    export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
    export KBUILD_ARFLAGS
    
    # When compiling out-of-tree modules, put MODVERDIR in the module
    # tree rather than in the kernel tree. The kernel tree might
    # even be read-only.
    export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
    
    # Files to ignore in find ... statements
    
    export 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
    export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
    			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
    
    # ===========================================================================
    # Rules shared between *config targets and build targets
    
    # Basic helpers built in scripts/basic/
    PHONY += scripts_basic
    scripts_basic:
    	$(Q)$(MAKE) $(build)=scripts/basic
    	$(Q)rm -f .tmp_quiet_recordmcount
    
    # To avoid any implicit rule to kick in, define an empty command.
    scripts/basic/%: scripts_basic ;
    
    PHONY += outputmakefile
    # outputmakefile generates a Makefile in the output directory, if using a
    # separate output directory. This allows convenient use of make in the
    # output directory.
    outputmakefile:
    ifneq ($(KBUILD_SRC),)
    	$(Q)ln -fsn $(srctree) source
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
    	    $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
    endif
    
    # Support for using generic headers in asm-generic
    PHONY += asm-generic uapi-asm-generic
    asm-generic: uapi-asm-generic
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
    	            src=asm obj=arch/$(SRCARCH)/include/generated/asm
    uapi-asm-generic:
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
    	            src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
    
    # To make sure we do not include .config for any of the *config targets
    # catch them early, and hand them over to scripts/kconfig/Makefile
    # It is allowed to specify more targets when calling make, including
    # mixing *config targets and build targets.
    # For example 'make oldconfig all'.
    # Detect when mixed targets is specified, and make a second invocation
    # of make so .config is not included in this case either (for *config).
    
    version_h := include/generated/uapi/linux/version.h
    old_version_h := include/linux/version.h
    
    no-dot-config-targets := clean mrproper distclean \
    			 cscope gtags TAGS tags help% %docs check% coccicheck \
    			 $(version_h) headers_% archheaders archscripts \
    			 kernelversion %src-pkg
    
    config-targets := 0
    mixed-targets  := 0
    dot-config     := 1
    
    ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
    	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
    		dot-config := 0
    	endif
    endif
    
    ifeq ($(KBUILD_EXTMOD),)
            ifneq ($(filter config %config,$(MAKECMDGOALS)),)
                    config-targets := 1
                    ifneq ($(words $(MAKECMDGOALS)),1)
                            mixed-targets := 1
                    endif
            endif
    endif
    # install and modules_install need also be processed one by one
    ifneq ($(filter install,$(MAKECMDGOALS)),)
            ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
    	        mixed-targets := 1
            endif
    endif
    
    ifeq ($(mixed-targets),1)
    # ===========================================================================
    # We're called with mixed targets (*config and build targets).
    # Handle them one by one.
    
    PHONY += $(MAKECMDGOALS) __build_one_by_one
    
    $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
    	@:
    
    __build_one_by_one:
    	$(Q)set -e; \
    	for i in $(MAKECMDGOALS); do \
    		$(MAKE) -f $(srctree)/Makefile $$i; \
    	done
    
    else
    ifeq ($(config-targets),1)
    # ===========================================================================
    # *config targets only - make sure prerequisites are updated, and descend
    # in scripts/kconfig to make the *config target
    
    # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
    # KBUILD_DEFCONFIG may point out an alternative default configuration
    # used for 'make defconfig'
    include arch/$(SRCARCH)/Makefile
    export KBUILD_DEFCONFIG KBUILD_KCONFIG
    
    config: scripts_basic outputmakefile FORCE
    	$(Q)$(MAKE) $(build)=scripts/kconfig $@
    
    %config: scripts_basic outputmakefile FORCE
    	$(Q)$(MAKE) $(build)=scripts/kconfig $@
    
    else
    # ===========================================================================
    # Build targets only - this includes vmlinux, arch specific targets, clean
    # targets and others. In general all targets except *config targets.
    
    ifeq ($(KBUILD_EXTMOD),)
    # Additional helpers built in scripts/
    # Carefully list dependencies so we do not try to build scripts twice
    # in parallel
    PHONY += scripts
    scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
    	 asm-generic gcc-plugins
    	$(Q)$(MAKE) $(build)=$(@)
    
    # Objects we will link into vmlinux / subdirs we need to visit
    init-y		:= init/
    drivers-y	:= drivers/ sound/ firmware/
    net-y		:= net/
    libs-y		:= lib/
    core-y		:= usr/
    virt-y		:= virt/
    endif # KBUILD_EXTMOD
    
    ifeq ($(dot-config),1)
    # Read in config
    -include include/config/auto.conf
    
    ifeq ($(KBUILD_EXTMOD),)
    # Read in dependencies to all Kconfig* files, make sure to run
    # oldconfig if changes are detected.
    -include include/config/auto.conf.cmd
    
    # To avoid any implicit rule to kick in, define an empty command
    $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
    
    # If .config is newer than include/config/auto.conf, someone tinkered
    # with it and forgot to run make oldconfig.
    # if auto.conf.cmd is missing then we are probably in a cleaned tree so
    # we execute the config step to be sure to catch updated Kconfig files
    include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
    	$(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
    else
    # external modules needs include/generated/autoconf.h and include/config/auto.conf
    # but do not care if they are up-to-date. Use auto.conf to trigger the test
    PHONY += include/config/auto.conf
    
    include/config/auto.conf:
    	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
    	echo >&2;							\
    	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
    	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
    	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
    	echo >&2 ;							\
    	/bin/false)
    
    endif # KBUILD_EXTMOD
    
    else
    # Dummy target needed, because used as prerequisite
    include/config/auto.conf: ;
    endif # $(dot-config)
    
    # For the kernel to actually contain only the needed exported symbols,
    # we have to build modules as well to determine what those symbols are.
    # (this can be evaluated only once include/config/auto.conf has been included)
    ifdef CONFIG_TRIM_UNUSED_KSYMS
      KBUILD_MODULES := 1
    endif
    
    # The all: target is the default when no target is given on the
    # command line.
    # This allow a user to issue only 'make' to build a kernel including modules
    # Defaults to vmlinux, but the arch makefile usually adds further targets
    all: vmlinux
    
    # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
    # values of the respective KBUILD_* variables
    ARCH_CPPFLAGS :=
    ARCH_AFLAGS :=
    ARCH_CFLAGS :=
    include arch/$(SRCARCH)/Makefile
    
    KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
    KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
    KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
    KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
    KBUILD_CFLAGS	+= $(call cc-disable-warning, int-in-bool-context)
    
    ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
    KBUILD_CFLAGS	+= $(call cc-option,-Oz,-Os)
    KBUILD_CFLAGS	+= $(call cc-disable-warning,maybe-uninitialized,)
    else
    ifdef CONFIG_PROFILE_ALL_BRANCHES
    KBUILD_CFLAGS	+= -O2 $(call cc-disable-warning,maybe-uninitialized,)
    else
    KBUILD_CFLAGS   += -O2
    endif
    endif
    
    KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
    			$(call cc-disable-warning,maybe-uninitialized,))
    
    # Tell gcc to never replace conditional load with a non-conditional one
    KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
    
    # check for 'asm goto'
    ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
    	KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
    	KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
    endif
    
    include scripts/Makefile.gcc-plugins
    
    ifdef CONFIG_READABLE_ASM
    # Disable optimizations that make assembler listings hard to read.
    # reorder blocks reorders the control in the function
    # ipa clone creates specialized cloned functions
    # partial inlining inlines only parts of functions
    KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
                     $(call cc-option,-fno-ipa-cp-clone,) \
                     $(call cc-option,-fno-partial-inlining)
    endif
    
    ifneq ($(CONFIG_FRAME_WARN),0)
    KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
    endif
    
    # This selects the stack protector compiler flag. Testing it is delayed
    # until after .config has been reprocessed, in the prepare-compiler-check
    # target.
    ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
      stackp-flag := -fstack-protector
      stackp-name := REGULAR
    else
    ifdef CONFIG_CC_STACKPROTECTOR_STRONG
      stackp-flag := -fstack-protector-strong
      stackp-name := STRONG
    else
      # Force off for distro compilers that enable stack protector by default.
      stackp-flag := $(call cc-option, -fno-stack-protector)
    endif
    endif
    # Find arch-specific stack protector compiler sanity-checking script.
    ifdef CONFIG_CC_STACKPROTECTOR
      stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
      stackp-check := $(wildcard $(stackp-path))
    endif
    KBUILD_CFLAGS += $(stackp-flag)
    
    ifeq ($(cc-name),clang)
    ifneq ($(CROSS_COMPILE),)
    CLANG_TARGET	:= -target $(notdir $(CROSS_COMPILE:%-=%))
    GCC_TOOLCHAIN	:= $(realpath $(dir $(shell which $(LD)))/..)
    endif
    ifneq ($(GCC_TOOLCHAIN),)
    CLANG_GCC_TC	:= -gcc-toolchain $(GCC_TOOLCHAIN)
    endif
    KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
    KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
    KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
    KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
    KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
    KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
    KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
    # Quiet clang warning: comparison of unsigned expression < 0 is always false
    KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
    # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
    # source of a reference will be _MergedGlobals and not on of the whitelisted names.
    # See modpost pattern 2
    KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
    KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
    KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
    KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
    else
    
    # These warnings generated too much noise in a regular build.
    # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
    KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
    KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
    endif
    
    ifdef CONFIG_FRAME_POINTER
    KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
    else
    # Some targets (ARM with Thumb2, for example), can't be built with frame
    # pointers.  For those, we don't have FUNCTION_TRACER automatically
    # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
    # incompatible with -fomit-frame-pointer with current GCC, so we don't use
    # -fomit-frame-pointer with FUNCTION_TRACER.
    ifndef CONFIG_FUNCTION_TRACER
    KBUILD_CFLAGS	+= -fomit-frame-pointer
    endif
    endif
    
    KBUILD_CFLAGS   += $(call cc-option, -fno-var-tracking-assignments)
    
    ifdef CONFIG_DEBUG_INFO
    ifdef CONFIG_DEBUG_INFO_SPLIT
    KBUILD_CFLAGS   += $(call cc-option, -gsplit-dwarf, -g)
    else
    KBUILD_CFLAGS	+= -g
    endif
    KBUILD_AFLAGS	+= -Wa,-gdwarf-2
    endif
    ifdef CONFIG_DEBUG_INFO_DWARF4
    KBUILD_CFLAGS	+= $(call cc-option, -gdwarf-4,)
    endif
    
    ifdef CONFIG_DEBUG_INFO_REDUCED
    KBUILD_CFLAGS 	+= $(call cc-option, -femit-struct-debug-baseonly) \
    		   $(call cc-option,-fno-var-tracking)
    endif
    
    ifdef CONFIG_FUNCTION_TRACER
    ifndef CC_FLAGS_FTRACE
    CC_FLAGS_FTRACE := -pg
    endif
    export CC_FLAGS_FTRACE
    ifdef CONFIG_HAVE_FENTRY
    CC_USING_FENTRY	:= $(call cc-option, -mfentry -DCC_USING_FENTRY)
    endif
    KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
    KBUILD_AFLAGS	+= $(CC_USING_FENTRY)
    ifdef CONFIG_DYNAMIC_FTRACE
    	ifdef CONFIG_HAVE_C_RECORDMCOUNT
    		BUILD_C_RECORDMCOUNT := y
    		export BUILD_C_RECORDMCOUNT
    	endif
    endif
    endif
    
    # We trigger additional mismatches with less inlining
    ifdef CONFIG_DEBUG_SECTION_MISMATCH
    KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
    endif
    
    ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
    KBUILD_CFLAGS	+= $(call cc-option,-ffunction-sections,)
    KBUILD_CFLAGS	+= $(call cc-option,-fdata-sections,)
    endif
    
    # arch Makefile may override CC so keep this after arch Makefile is included
    NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
    CHECKFLAGS     += $(NOSTDINC_FLAGS)
    
    # warn about C99 declaration after statement
    KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
    
    # disable pointer signed / unsigned warnings in gcc 4.0
    KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
    
    # disable invalid "can't wrap" optimizations for signed / pointers
    KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
    
    # conserve stack if available
    KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
    
    # disallow errors like 'EXPORT_GPL(foo);' with missing header
    KBUILD_CFLAGS   += $(call cc-option,-Werror=implicit-int)
    
    # require functions to have arguments in prototypes, not empty 'int foo()'
    KBUILD_CFLAGS   += $(call cc-option,-Werror=strict-prototypes)
    
    # Prohibit date/time macros, which would make the build non-deterministic
    KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
    
    # enforce correct pointer usage
    KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
    
    # Require designated initializers for all marked structures
    KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
    
    # use the deterministic mode of AR if available
    KBUILD_ARFLAGS := $(call ar-option,D)
    
    include scripts/Makefile.kasan
    include scripts/Makefile.extrawarn
    include scripts/Makefile.ubsan
    
    # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
    # last assignments
    KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
    KBUILD_AFLAGS   += $(ARCH_AFLAGS)   $(KAFLAGS)
    KBUILD_CFLAGS   += $(ARCH_CFLAGS)   $(KCFLAGS)
    
    # Use --build-id when available.
    LDFLAGS_BUILD_ID := $(patsubst -Wl$(comma)%,%,\
    			      $(call cc-ldoption, -Wl$(comma)--build-id,))
    KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
    LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
    
    ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
    LDFLAGS_vmlinux	+= $(call ld-option, --gc-sections,)
    endif
    
    ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
    LDFLAGS_vmlinux	+= $(call ld-option, -X,)
    endif
    
    # Default kernel image to build when no specific target is given.
    # KBUILD_IMAGE may be overruled on the command line or
    # set in the environment
    # Also any assignments in arch/$(ARCH)/Makefile take precedence over
    # this default value
    export KBUILD_IMAGE ?= vmlinux
    
    #
    # INSTALL_PATH specifies where to place the updated kernel and system map
    # images. Default is /boot, but you can set it to other values
    export	INSTALL_PATH ?= /boot
    
    #
    # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
    # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
    # an argument if needed. Otherwise it defaults to the kernel install path
    #
    export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
    
    #
    # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
    # relocations required by build roots.  This is not defined in the
    # makefile but the argument can be passed to make if needed.
    #
    
    MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
    export MODLIB
    
    #
    # INSTALL_MOD_STRIP, if defined, will cause modules to be
    # stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
    # the default option --strip-debug will be used.  Otherwise,
    # INSTALL_MOD_STRIP value will be used as the options to the strip command.
    
    ifdef INSTALL_MOD_STRIP
    ifeq ($(INSTALL_MOD_STRIP),1)
    mod_strip_cmd = $(STRIP) --strip-debug
    else
    mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
    endif # INSTALL_MOD_STRIP=1
    else
    mod_strip_cmd = true
    endif # INSTALL_MOD_STRIP
    export mod_strip_cmd
    
    # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
    # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
    # or CONFIG_MODULE_COMPRESS_XZ.
    
    mod_compress_cmd = true
    ifdef CONFIG_MODULE_COMPRESS
      ifdef CONFIG_MODULE_COMPRESS_GZIP
        mod_compress_cmd = gzip -n -f
      endif # CONFIG_MODULE_COMPRESS_GZIP
      ifdef CONFIG_MODULE_COMPRESS_XZ
        mod_compress_cmd = xz -f
      endif # CONFIG_MODULE_COMPRESS_XZ
    endif # CONFIG_MODULE_COMPRESS
    export mod_compress_cmd
    
    # Select initial ramdisk compression format, default is gzip(1).
    # This shall be used by the dracut(8) tool while creating an initramfs image.
    #
    INITRD_COMPRESS-y                  := gzip
    INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
    INITRD_COMPRESS-$(CONFIG_RD_LZMA)  := lzma
    INITRD_COMPRESS-$(CONFIG_RD_XZ)    := xz
    INITRD_COMPRESS-$(CONFIG_RD_LZO)   := lzo
    INITRD_COMPRESS-$(CONFIG_RD_LZ4)   := lz4
    # do not export INITRD_COMPRESS, since we didn't actually
    # choose a sane default compression above.
    # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
    
    ifdef CONFIG_MODULE_SIG_ALL
    $(eval $(call config_filename,MODULE_SIG_KEY))
    
    mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
    else
    mod_sign_cmd = true
    endif
    export mod_sign_cmd
    
    ifdef CONFIG_STACK_VALIDATION
      has_libelf := $(call try-run,\
    		echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
      ifeq ($(has_libelf),1)
        objtool_target := tools/objtool FORCE
      else
        $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
        SKIP_STACK_VALIDATION := 1
        export SKIP_STACK_VALIDATION
      endif
    endif
    
    
    ifeq ($(KBUILD_EXTMOD),)
    core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
    
    vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
    		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
    		     $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
    
    vmlinux-alldirs	:= $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
    		     $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
    
    init-y		:= $(patsubst %/, %/built-in.o, $(init-y))
    core-y		:= $(patsubst %/, %/built-in.o, $(core-y))
    drivers-y	:= $(patsubst %/, %/built-in.o, $(drivers-y))
    net-y		:= $(patsubst %/, %/built-in.o, $(net-y))
    libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))
    libs-y2		:= $(filter-out %.a, $(patsubst %/, %/built-in.o, $(libs-y)))
    virt-y		:= $(patsubst %/, %/built-in.o, $(virt-y))
    
    # Externally visible symbols (used by link-vmlinux.sh)
    export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
    export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
    export KBUILD_VMLINUX_LIBS := $(libs-y1)
    export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
    export LDFLAGS_vmlinux
    # used by scripts/package/Makefile
    export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
    
    vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
    
    # Include targets which we want to execute sequentially if the rest of the
    # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
    # evaluated more than once.
    PHONY += vmlinux_prereq
    vmlinux_prereq: $(vmlinux-deps) FORCE
    ifdef CONFIG_HEADERS_CHECK
    	$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
    endif
    ifdef CONFIG_GDB_SCRIPTS
    	$(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
    endif
    ifdef CONFIG_TRIM_UNUSED_KSYMS
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
    	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
    endif
    
    # standalone target for easier testing
    include/generated/autoksyms.h: FORCE
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
    
    ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
    
    # Final link of vmlinux with optional arch pass after final link
    cmd_link-vmlinux =                                                 \
    	$(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ;    \
    	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
    
    vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
    	+$(call if_changed,link-vmlinux)
    
    # Build samples along the rest of the kernel
    ifdef CONFIG_SAMPLES
    vmlinux-dirs += samples
    endif
    
    # The actual objects are generated when descending,
    # make sure no implicit rule kicks in
    $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
    
    # Handle descending into subdirectories listed in $(vmlinux-dirs)
    # Preset locale variables to speed up the build process. Limit locale
    # tweaks to this spot to avoid wrong language settings when running
    # make menuconfig etc.
    # Error messages still appears in the original language
    
    PHONY += $(vmlinux-dirs)
    $(vmlinux-dirs): prepare scripts
    	$(Q)$(MAKE) $(build)=$@
    
    define filechk_kernel.release
    	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
    endef
    
    # Store (new) KERNELRELEASE string in include/config/kernel.release
    include/config/kernel.release: include/config/auto.conf FORCE
    	$(call filechk,kernel.release)
    
    
    # Things we need to do before we recursively start building the kernel
    # or the modules are listed in "prepare".
    # A multi level approach is used. prepareN is processed before prepareN-1.
    # archprepare is used in arch Makefiles and when processed asm symlink,
    # version.h and scripts_basic is processed / created.
    
    # Listed in dependency order
    PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
    
    # prepare3 is used to check if we are building in a separate output directory,
    # and if so do:
    # 1) Check that make has not been executed in the kernel src $(srctree)
    prepare3: include/config/kernel.release
    ifneq ($(KBUILD_SRC),)
    	@$(kecho) '  Using $(srctree) as source for kernel'
    	$(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
    		echo >&2 "  $(srctree) is not clean, please run 'make mrproper'"; \
    		echo >&2 "  in the '$(srctree)' directory.";\
    		/bin/false; \
    	fi;
    endif
    
    # prepare2 creates a makefile if using a separate output directory.
    # From this point forward, .config has been reprocessed, so any rules
    # that need to depend on updated CONFIG_* values can be checked here.
    prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
    
    prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
                       include/config/auto.conf
    	$(cmd_crmodverdir)
    
    archprepare: archheaders archscripts prepare1 scripts_basic
    
    prepare0: archprepare gcc-plugins
    	$(Q)$(MAKE) $(build)=.
    
    # All the preparing..
    prepare: prepare0 prepare-objtool
    
    PHONY += prepare-objtool
    prepare-objtool: $(objtool_target)
    
    # Check for CONFIG flags that require compiler support. Abort the build
    # after .config has been processed, but before the kernel build starts.
    #
    # For security-sensitive CONFIG options, we don't want to fallback and/or
    # silently change which compiler flags will be used, since that leads to
    # producing kernels with different security feature characteristics
    # depending on the compiler used. (For example, "But I selected
    # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
    PHONY += prepare-compiler-check
    prepare-compiler-check: FORCE
    # Make sure compiler supports requested stack protector flag.
    ifdef stackp-name
      ifeq ($(call cc-option, $(stackp-flag)),)
    	@echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
    		  $(stackp-flag) not supported by compiler >&2 && exit 1
      endif
    endif
    # Make sure compiler does not have buggy stack-protector support.
    ifdef stackp-check
      ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
    	@echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
                      $(stackp-flag) available but compiler is broken >&2 && exit 1
      endif
    endif
    	@:
    
    # Generate some files
    # ---------------------------------------------------------------------------
    
    # KERNELRELEASE can change from a few different places, meaning version.h
    # needs to be updated, so this check is forced on all builds
    
    uts_len := 64
    define filechk_utsrelease.h
    	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
    	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
    	  exit 1;                                                         \
    	fi;                                                               \
    	(echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
    endef
    
    define filechk_version.h
    	(echo \#define LINUX_VERSION_CODE $(shell                         \
    	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
    	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
    endef
    
    $(version_h): $(srctree)/Makefile FORCE
    	$(call filechk,version.h)
    	$(Q)rm -f $(old_version_h)
    
    include/generated/utsrelease.h: include/config/kernel.release FORCE
    	$(call filechk,utsrelease.h)
    
    PHONY += headerdep
    headerdep:
    	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
    	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
    
    # ---------------------------------------------------------------------------
    # Firmware install
    INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
    export INSTALL_FW_PATH
    
    PHONY += firmware_install
    firmware_install:
    	@mkdir -p $(objtree)/firmware
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
    
    # ---------------------------------------------------------------------------
    # Kernel headers
    
    #Default location for installed headers
    export INSTALL_HDR_PATH = $(objtree)/usr
    
    # If we do an all arch process set dst to include/arch-$(hdr-arch)
    hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(hdr-arch), dst=include)
    
    PHONY += archheaders
    archheaders:
    
    PHONY += archscripts
    archscripts:
    
    PHONY += __headers
    __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
    	$(Q)$(MAKE) $(build)=scripts build_unifdef
    
    PHONY += headers_install_all
    headers_install_all:
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
    
    PHONY += headers_install
    headers_install: __headers
    	$(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
    	  $(error Headers not exportable for the $(SRCARCH) architecture))
    	$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
    	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi $(hdr-dst)
    
    PHONY += headers_check_all
    headers_check_all: headers_install_all
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
    
    PHONY += headers_check
    headers_check: headers_install
    	$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
    	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi $(hdr-dst) HDRCHECK=1
    
    # ---------------------------------------------------------------------------
    # Kernel selftest
    
    PHONY += kselftest
    kselftest:
    	$(Q)$(MAKE) -C tools/testing/selftests run_tests
    
    PHONY += kselftest-clean
    kselftest-clean:
    	$(Q)$(MAKE) -C tools/testing/selftests clean
    
    PHONY += kselftest-merge
    kselftest-merge:
    	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
    		-m $(objtree)/.config \
    		$(srctree)/tools/testing/selftests/*/config
    	+$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
    
    # ---------------------------------------------------------------------------
    # Modules
    
    ifdef CONFIG_MODULES
    
    # By default, build modules as well
    
    all: modules
    
    # Build modules
    #
    # A module can be listed more than once in obj-m resulting in
    # duplicate lines in modules.order files.  Those are removed
    # using awk while concatenating to the final file.
    
    PHONY += modules
    modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
    	$(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
    	@$(kecho) '  Building modules, stage 2.';
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
    
    modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
    	$(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
    
    %/modules.builtin: include/config/auto.conf
    	$(Q)$(MAKE) $(modbuiltin)=$*
    
    
    # Target to prepare building external modules
    PHONY += modules_prepare
    modules_prepare: prepare scripts
    
    # Target to install modules
    PHONY += modules_install
    modules_install: _modinst_ _modinst_post
    
    PHONY += _modinst_
    _modinst_:
    	@rm -rf $(MODLIB)/kernel
    	@rm -f $(MODLIB)/source
    	@mkdir -p $(MODLIB)/kernel
    	@ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
    	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
    		rm -f $(MODLIB)/build ; \
    		ln -s $(CURDIR) $(MODLIB)/build ; \
    	fi
    	@cp -f $(objtree)/modules.order $(MODLIB)/
    	@cp -f $(objtree)/modules.builtin $(MODLIB)/
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
    
    # This depmod is only for convenience to give the initial
    # boot a modules.dep even before / is mounted read-write.  However the
    # boot script depmod is the master version.
    PHONY += _modinst_post
    _modinst_post: _modinst_
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
    	$(call cmd,depmod)
    
    ifeq ($(CONFIG_MODULE_SIG), y)
    PHONY += modules_sign
    modules_sign:
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
    endif
    
    else # CONFIG_MODULES
    
    # Modules not configured
    # ---------------------------------------------------------------------------
    
    PHONY += modules modules_install
    modules modules_install:
    	@echo >&2
    	@echo >&2 "The present kernel configuration has modules disabled."
    	@echo >&2 "Type 'make config' and enable loadable module support."
    	@echo >&2 "Then build a kernel with module support enabled."
    	@echo >&2
    	@exit 1
    
    endif # CONFIG_MODULES
    
    ###
    # Cleaning is done on three levels.
    # make clean     Delete most generated files
    #                Leave enough to build external modules
    # make mrproper  Delete the current configuration, and all generated files
    # make distclean Remove editor backup files, patch leftover files and the like
    
    # Directories & files removed with 'make clean'
    CLEAN_DIRS  += $(MODVERDIR)
    
    # Directories & files removed with 'make mrproper'
    MRPROPER_DIRS  += include/config usr/include include/generated          \
    		  arch/*/include/generated .tmp_objdiff
    MRPROPER_FILES += .config .config.old .version .old_version \
    		  Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
    		  signing_key.pem signing_key.priv signing_key.x509	\
    		  x509.genkey extra_certificates signing_key.x509.keyid	\
    		  signing_key.x509.signer vmlinux-gdb.py
    
    # clean - Delete most, but leave enough to build external modules
    #
    clean: rm-dirs  := $(CLEAN_DIRS)
    clean: rm-files := $(CLEAN_FILES)
    clean-dirs      := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
    
    PHONY += $(clean-dirs) clean archclean vmlinuxclean
    $(clean-dirs):
    	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
    
    vmlinuxclean:
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
    	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
    
    clean: archclean vmlinuxclean
    
    # mrproper - Delete all generated files, including .config
    #
    mrproper: rm-dirs  := $(wildcard $(MRPROPER_DIRS))
    mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
    mrproper-dirs      := $(addprefix _mrproper_,scripts)
    
    PHONY += $(mrproper-dirs) mrproper archmrproper
    $(mrproper-dirs):
    	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
    
    mrproper: clean archmrproper $(mrproper-dirs)
    	$(call cmd,rmdirs)
    	$(call cmd,rmfiles)
    
    # distclean
    #
    PHONY += distclean
    
    distclean: mrproper
    	@find $(srctree) $(RCS_FIND_IGNORE) \
    		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
    		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
    		-o -name 'core' \) \
    		-type f -print | xargs rm -f
    
    
    # Packaging of the kernel to various formats
    # ---------------------------------------------------------------------------
    # rpm target kept for backward compatibility
    package-dir	:= scripts/package
    
    %src-pkg: FORCE
    	$(Q)$(MAKE) $(build)=$(package-dir) $@
    %pkg: include/config/kernel.release FORCE
    	$(Q)$(MAKE) $(build)=$(package-dir) $@
    rpm: include/config/kernel.release FORCE
    	$(Q)$(MAKE) $(build)=$(package-dir) $@
    
    
    # Brief documentation of the typical targets used
    # ---------------------------------------------------------------------------
    
    boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
    boards := $(sort $(notdir $(boards)))
    board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
    board-dirs := $(sort $(notdir $(board-dirs:/=)))
    
    PHONY += help
    help:
    	@echo  'Cleaning targets:'
    	@echo  '  clean		  - Remove most generated files but keep the config and'
    	@echo  '                    enough build support to build external modules'
    	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
    	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
    	@echo  ''
    	@echo  'Configuration targets:'
    	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
    	@echo  ''
    	@echo  'Other generic targets:'
    	@echo  '  all		  - Build all targets marked with [*]'
    	@echo  '* vmlinux	  - Build the bare kernel'
    	@echo  '* modules	  - Build all modules'
    	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
    	@echo  '  firmware_install- Install all firmware to INSTALL_FW_PATH'
    	@echo  '                    (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
    	@echo  '  dir/            - Build all files in dir and below'
    	@echo  '  dir/file.[ois]  - Build specified target only'
    	@echo  '  dir/file.ll     - Build the LLVM assembly file'
    	@echo  '                    (requires compiler support for LLVM assembly generation)'
    	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
    	@echo  '                    (requires a recent binutils and recent build (System.map))'
    	@echo  '  dir/file.ko     - Build module including final link'
    	@echo  '  modules_prepare - Set up for building external modules'
    	@echo  '  tags/TAGS	  - Generate tags file for editors'
    	@echo  '  cscope	  - Generate cscope index'
    	@echo  '  gtags           - Generate GNU GLOBAL index'
    	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
    	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
    	@echo  '  image_name	  - Output the image name (use with make -s)'
    	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
    	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
    	 echo  ''
    	@echo  'Static analysers:'
    	@echo  '  checkstack      - Generate a list of stack hogs'
    	@echo  '  namespacecheck  - Name space analysis on compiled kernel'
    	@echo  '  versioncheck    - Sanity check on version.h usage'
    	@echo  '  includecheck    - Check for duplicate included header files'
    	@echo  '  export_report   - List the usages of all exported symbols'
    	@echo  '  headers_check   - Sanity check on exported headers'
    	@echo  '  headerdep       - Detect inclusion cycles in headers'
    	@$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
    	@echo  ''
    	@echo  'Kernel selftest:'
    	@echo  '  kselftest       - Build and run kernel selftest (run as root)'
    	@echo  '                    Build, install, and boot kernel before'
    	@echo  '                    running kselftest on it'
    	@echo  '  kselftest-clean - Remove all generated kselftest files'
    	@echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existed'
    	@echo  '                    .config.'
    	@echo  ''
    	@echo 'Userspace tools targets:'
    	@echo '  use "make tools/help"'
    	@echo '  or  "cd tools; make help"'
    	@echo  ''
    	@echo  'Kernel packaging:'
    	@$(MAKE) $(build)=$(package-dir) help
    	@echo  ''
    	@echo  'Documentation targets:'
    	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
    	@echo  ''
    	@echo  'Architecture specific targets ($(SRCARCH)):'
    	@$(if $(archhelp),$(archhelp),\
    		echo '  No architecture specific help defined for $(SRCARCH)')
    	@echo  ''
    	@$(if $(boards), \
    		$(foreach b, $(boards), \
    		printf "  %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
    		echo '')
    	@$(if $(board-dirs), \
    		$(foreach b, $(board-dirs), \
    		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
    		printf "  %-16s - Show all of the above\\n" help-boards; \
    		echo '')
    
    	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
    	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
    	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
    	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK (sparse by default)'
    	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
    	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
    	@echo  '  make W=n   [targets] Enable extra gcc checks, n=1,2,3 where'
    	@echo  '		1: warnings which may be relevant and do not occur too often'
    	@echo  '		2: warnings which occur quite often but may still be relevant'
    	@echo  '		3: more obscure warnings, can most likely be ignored'
    	@echo  '		Multiple levels can be combined with W=12 or W=123'
    	@echo  ''
    	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
    	@echo  'For further info see the ./README file'
    
    
    help-board-dirs := $(addprefix help-,$(board-dirs))
    
    help-boards: $(help-board-dirs)
    
    boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
    
    $(help-board-dirs): help-%:
    	@echo  'Architecture specific targets ($(SRCARCH) $*):'
    	@$(if $(boards-per-dir), \
    		$(foreach b, $(boards-per-dir), \
    		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
    		echo '')
    
    
    # Documentation targets
    # ---------------------------------------------------------------------------
    DOC_TARGETS := xmldocs sgmldocs psdocs latexdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs linkcheckdocs
    PHONY += $(DOC_TARGETS)
    $(DOC_TARGETS): scripts_basic FORCE
    	$(Q)$(MAKE) $(build)=Documentation $@
    
    else # KBUILD_EXTMOD
    
    ###
    # External module support.
    # When building external modules the kernel used as basis is considered
    # read-only, and no consistency checks are made and the make
    # system is not used on the basis kernel. If updates are required
    # in the basis kernel ordinary make commands (without M=...) must
    # be used.
    #
    # The following are the only valid targets when building external
    # modules.
    # make M=dir clean     Delete all automatically generated files
    # make M=dir modules   Make all modules in specified dir
    # make M=dir	       Same as 'make M=dir modules'
    # make M=dir modules_install
    #                      Install the modules built in the module directory
    #                      Assumes install directory is already created
    
    # We are always building modules
    KBUILD_MODULES := 1
    PHONY += crmodverdir
    crmodverdir:
    	$(cmd_crmodverdir)
    
    PHONY += $(objtree)/Module.symvers
    $(objtree)/Module.symvers:
    	@test -e $(objtree)/Module.symvers || ( \
    	echo; \
    	echo "  WARNING: Symbol version dump $(objtree)/Module.symvers"; \
    	echo "           is missing; modules will have no dependencies and modversions."; \
    	echo )
    
    module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
    PHONY += $(module-dirs) modules
    $(module-dirs): crmodverdir $(objtree)/Module.symvers
    	$(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
    
    modules: $(module-dirs)
    	@$(kecho) '  Building modules, stage 2.';
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
    
    PHONY += modules_install
    modules_install: _emodinst_ _emodinst_post
    
    install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
    PHONY += _emodinst_
    _emodinst_:
    	$(Q)mkdir -p $(MODLIB)/$(install-dir)
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
    
    PHONY += _emodinst_post
    _emodinst_post: _emodinst_
    	$(call cmd,depmod)
    
    clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
    
    PHONY += $(clean-dirs) clean
    $(clean-dirs):
    	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
    
    clean:	rm-dirs := $(MODVERDIR)
    clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
    
    PHONY += help
    help:
    	@echo  '  Building external modules.'
    	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
    	@echo  ''
    	@echo  '  modules         - default target, build the module(s)'
    	@echo  '  modules_install - install the module'
    	@echo  '  clean           - remove generated files in module directory only'
    	@echo  ''
    
    # Dummies...
    PHONY += prepare scripts
    prepare: ;
    scripts: ;
    endif # KBUILD_EXTMOD
    
    clean: $(clean-dirs)
    	$(call cmd,rmdirs)
    	$(call cmd,rmfiles)
    	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
    		\( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
    		-o -name '*.ko.*' \
    		-o -name '*.dwo'  \
    		-o -name '*.su'  \
    		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
    		-o -name '*.symtypes' -o -name 'modules.order' \
    		-o -name modules.builtin -o -name '.tmp_*.o.*' \
    		-o -name '*.c.[012]*.*' \
    		-o -name '*.ll' \
    		-o -name '*.gcno' \) -type f -print | xargs rm -f
    
    # Generate tags for editors
    # ---------------------------------------------------------------------------
    quiet_cmd_tags = GEN     $@
          cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
    
    tags TAGS cscope gtags: FORCE
    	$(call cmd,tags)
    
    # Scripts to check various things for consistency
    # ---------------------------------------------------------------------------
    
    PHONY += includecheck versioncheck coccicheck namespacecheck export_report
    
    includecheck:
    	find $(srctree)/* $(RCS_FIND_IGNORE) \
    		-name '*.[hcS]' -type f -print | sort \
    		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
    
    versioncheck:
    	find $(srctree)/* $(RCS_FIND_IGNORE) \
    		-name '*.[hcS]' -type f -print | sort \
    		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
    
    coccicheck:
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
    
    namespacecheck:
    	$(PERL) $(srctree)/scripts/namespace.pl
    
    export_report:
    	$(PERL) $(srctree)/scripts/export_report.pl
    
    endif #ifeq ($(config-targets),1)
    endif #ifeq ($(mixed-targets),1)
    
    PHONY += checkstack kernelrelease kernelversion image_name
    
    # UML needs a little special treatment here.  It wants to use the host
    # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
    # else wants $(ARCH), including people doing cross-builds, which means
    # that $(SUBARCH) doesn't work here.
    ifeq ($(ARCH), um)
    CHECKSTACK_ARCH := $(SUBARCH)
    else
    CHECKSTACK_ARCH := $(ARCH)
    endif
    checkstack:
    	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
    	$(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
    
    kernelrelease:
    	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
    
    kernelversion:
    	@echo $(KERNELVERSION)
    
    image_name:
    	@echo $(KBUILD_IMAGE)
    
    # Clear a bunch of variables before executing the submake
    tools/: FORCE
    	$(Q)mkdir -p $(objtree)/tools
    	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
    
    tools/%: FORCE
    	$(Q)mkdir -p $(objtree)/tools
    	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
    
    # Single targets
    # ---------------------------------------------------------------------------
    # Single targets are compatible with:
    # - build with mixed source and output
    # - build with separate output dir 'make O=...'
    # - external modules
    #
    #  target-dir => where to store outputfile
    #  build-dir  => directory in kernel source tree to use
    
    ifeq ($(KBUILD_EXTMOD),)
            build-dir  = $(patsubst %/,%,$(dir $@))
            target-dir = $(dir $@)
    else
            zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
            build-dir  = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
            target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
    endif
    
    %.s: %.c prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    %.i: %.c prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    %.o: %.c prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    %.lst: %.c prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    %.s: %.S prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    %.o: %.S prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    %.symtypes: %.c prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    %.ll: %.c prepare scripts FORCE
    	$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
    
    # Modules
    /: prepare scripts FORCE
    	$(cmd_crmodverdir)
    	$(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
    	$(build)=$(build-dir)
    # Make sure the latest headers are built for Documentation
    Documentation/ samples/: headers_install
    %/: prepare scripts FORCE
    	$(cmd_crmodverdir)
    	$(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
    	$(build)=$(build-dir)
    %.ko: prepare scripts FORCE
    	$(cmd_crmodverdir)
    	$(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1)   \
    	$(build)=$(build-dir) $(@:.ko=.o)
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
    
    # FIXME Should go into a make.lib or something
    # ===========================================================================
    
    quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN   $(wildcard $(rm-dirs)))
          cmd_rmdirs = rm -rf $(rm-dirs)
    
    quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
          cmd_rmfiles = rm -f $(rm-files)
    
    # Run depmod only if we have System.map and depmod is executable
    quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
          cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
                       $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
    
    # Create temporary dir for module support files
    # clean it up only when building all modules
    cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
                      $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
    
    # read all saved command lines
    
    targets := $(wildcard $(sort $(targets)))
    cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
    
    ifneq ($(cmd_files),)
      $(cmd_files): ;	# Do not try to update included dependency files
      include $(cmd_files)
    endif
    
    endif	# skip-makefile
    
    PHONY += FORCE
    FORCE:
    
    # Declare the contents of the .PHONY variable as phony.  We keep that
    # information in a variable so we can use it in if_changed and friends.
    .PHONY: $(PHONY)