# SPDX-License-Identifier: GPL-2.0
  VERSION = 4
  PATCHLEVEL = 14
  SUBLEVEL = 98
  EXTRAVERSION =
  NAME = Petit Gorille
  
  # *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.
  
  # That's our default target when none is given on the command line
  PHONY := _all
  _all:
  
  # 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
  
  # 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
  
  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
  
  export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
  
  objtree		:= .
  src		:= $(srctree)
  obj		:= $(objtree)
  
  VPATH		:= $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
  
  export srctree objtree VPATH
  
  # 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
  
  # We need some generic definitions (do not try to remake the file).
  scripts/Kbuild.include: ;
  include scripts/Kbuild.include
  
  # 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
  
  # 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 2>/dev/null)
  HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
  HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
  
  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)
  
  # Make variables (CC, etc...)
  AS		= $(CROSS_COMPILE)as
  LD		= $(CROSS_COMPILE)ld
  LDGOLD		= $(CROSS_COMPILE)ld.gold
  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 =
  
  # 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_AFLAGS   := -D__ASSEMBLY__
  KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
  		   -fno-strict-aliasing -fno-common -fshort-wchar \
  		   -Werror-implicit-function-declaration \
  		   -Wno-format-security \
  		   -std=gnu89
  KBUILD_CPPFLAGS := -D__KERNEL__
  KBUILD_AFLAGS_KERNEL :=
  KBUILD_CFLAGS_KERNEL :=
  KBUILD_AFLAGS_MODULE  := -DMODULE
  KBUILD_CFLAGS_MODULE  := -DMODULE
  KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
  GCC_PLUGINS_CFLAGS :=
  
  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
  export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE 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
  
  ifeq ($(cc-name),clang)
  ifneq ($(CROSS_COMPILE),)
  CLANG_TRIPLE	?= $(CROSS_COMPILE)
  CLANG_FLAGS	:= --target=$(notdir $(CLANG_TRIPLE:%-=%))
  GCC_TOOLCHAIN_DIR := $(dir $(shell which $(LD)))
  CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
  GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
  endif
  ifneq ($(GCC_TOOLCHAIN),)
  CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
  endif
  CLANG_FLAGS	+= -no-integrated-as
  KBUILD_CFLAGS	+= $(CLANG_FLAGS)
  KBUILD_AFLAGS	+= $(CLANG_FLAGS)
  export CLANG_FLAGS
  endif
  
  RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
  RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
  RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
  RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
  RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
  RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
  export RETPOLINE_CFLAGS
  export RETPOLINE_VDSO_CFLAGS
  
  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.
  
  # 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
  
  # 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
  
  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
  
  KBUILD_CFLAGS	+= $(call cc-option,-fno-PIE)
  KBUILD_AFLAGS	+= $(call cc-option,-fno-PIE)
  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,)
  export CFLAGS_GCOV CFLAGS_KCOV
  
  # Make toolchain changes before including arch/$(SRCARCH)/Makefile to ensure
  # ar/cc/ld-* macros return correct values.
  ifdef CONFIG_LTO_CLANG
  # use GNU gold with LLVMgold for LTO linking, and LD for vmlinux_link
  LDFINAL_vmlinux := $(LD)
  LD		:= $(LDGOLD)
  LDFLAGS		+= -plugin LLVMgold.so
  # use llvm-ar for building symbol tables from IR files, and llvm-dis instead
  # of objdump for processing symbol versions and exports
  LLVM_AR		:= llvm-ar
  LLVM_DIS	:= llvm-dis
  export LLVM_AR LLVM_DIS
  endif
  
  # 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)
  KBUILD_CFLAGS	+= $(call cc-disable-warning, attribute-alias)
  
  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)
  KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
  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)
  KBUILD_CFLAGS += $(call cc-disable-warning, duplicate-decl-specifier)
  # 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)
  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)
  endif
  
  KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
  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
  
  ifdef CONFIG_LTO_CLANG
  lto-clang-flags	:= -flto -fvisibility=hidden
  
  # allow disabling only clang LTO where needed
  DISABLE_LTO_CLANG := -fno-lto -fvisibility=default
  export DISABLE_LTO_CLANG
  endif
  
  ifdef CONFIG_LTO
  lto-flags	:= $(lto-clang-flags)
  KBUILD_CFLAGS	+= $(lto-flags)
  
  DISABLE_LTO	:= $(DISABLE_LTO_CLANG)
  export DISABLE_LTO
  
  # LDFINAL_vmlinux and LDFLAGS_FINAL_vmlinux can be set to override
  # the linker and flags for vmlinux_link.
  export LDFINAL_vmlinux LDFLAGS_FINAL_vmlinux
  endif
  
  ifdef CONFIG_CFI_CLANG
  cfi-clang-flags	+= -fsanitize=cfi
  DISABLE_CFI_CLANG := -fno-sanitize=cfi
  ifdef CONFIG_MODULES
  cfi-clang-flags	+= -fsanitize-cfi-cross-dso
  DISABLE_CFI_CLANG += -fno-sanitize-cfi-cross-dso
  endif
  ifdef CONFIG_CFI_PERMISSIVE
  cfi-clang-flags	+= -fsanitize-recover=cfi -fno-sanitize-trap=cfi
  endif
  
  # also disable CFI when LTO is disabled
  DISABLE_LTO_CLANG += $(DISABLE_CFI_CLANG)
  # allow disabling only clang CFI where needed
  export DISABLE_CFI_CLANG
  endif
  
  ifdef CONFIG_CFI
  # cfi-flags are re-tested in prepare-compiler-check
  cfi-flags	:= $(cfi-clang-flags)
  KBUILD_CFLAGS	+= $(cfi-flags)
  
  DISABLE_CFI	:= $(DISABLE_CFI_CLANG)
  DISABLE_LTO	+= $(DISABLE_CFI)
  export DISABLE_CFI
  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 stringop warnings in gcc 8+
  KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
  
  # disable invalid "can't wrap" optimizations for signed / pointers
  KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
  
  # clang sets -fmerge-all-constants by default as optimization, but this
  # is non-conforming behavior for C and in fact breaks the kernel, so we
  # need to disable it here generally.
  KBUILD_CFLAGS	+= $(call cc-option,-fno-merge-all-constants)
  
  # for gcc -fno-merge-all-constants disables everything, but it is fine
  # to have actual conforming behavior enabled.
  KBUILD_CFLAGS	+= $(call cc-option,-fmerge-constants)
  
  # Make sure -fstack-check isn't enabled (like gentoo apparently did)
  KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
  
  # 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
      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 $(abspath $(srctree)/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
  
  # 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
  
  PHONY += prepare-objtool
  prepare-objtool: $(objtool_target)
  ifeq ($(SKIP_STACK_VALIDATION),1)
  ifdef CONFIG_UNWINDER_ORC
  	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
  	@false
  else
  	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
  endif
  endif
  
  # 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 we're using a supported toolchain with LTO_CLANG
  ifdef CONFIG_LTO_CLANG
    ifneq ($(call clang-ifversion, -ge, 0500, y), y)
  	@echo Cannot use CONFIG_LTO_CLANG: requires clang 5.0 or later >&2 && exit 1
    endif
    ifneq ($(call gold-ifversion, -ge, 112000000, y), y)
  	@echo Cannot use CONFIG_LTO_CLANG: requires GNU gold 1.12 or later >&2 && exit 1
    endif
  endif
  # Make sure compiler supports LTO flags
  ifdef lto-flags
    ifeq ($(call cc-option, $(lto-flags)),)
  	@echo Cannot use CONFIG_LTO: $(lto-flags) not supported by compiler \
  		>&2 && exit 1
    endif
  endif
  # Make sure compiler supports requested stack protector flag.
  ifdef stackp-name
    ifeq ($(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): \
                    $(stackp-flag) available but compiler is broken >&2 && exit 1
    endif
  endif
  ifdef cfi-flags
    ifeq ($(call cc-option, $(cfi-flags)),)
  	@echo Cannot use CONFIG_CFI: $(cfi-flags) not supported by compiler >&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
  
  # ---------------------------------------------------------------------------
  # 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 $(srctree)/tools/testing/selftests run_tests
  
  PHONY += kselftest-clean
  kselftest-clean:
  	$(Q)$(MAKE) -C $(srctree)/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
  
  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 $(abspath $(srctree)) $(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_
  	$(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  '  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 $(srctree)/scripts/Makefile.help checker-help
  	@echo  ''
  	@echo  'Kernel selftest:'
  	@echo  '  kselftest       - Build and run kernel selftest (run as root)'
  	@echo  '                    Build, install, and boot kernel before'
  	@echo  '                    running kselftest on it'
  	@echo  '  kselftest-clean - Remove all generated kselftest files'
  	@echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existing'
  	@echo  '                    .config.'
  	@echo  ''
  	@echo 'Userspace tools targets:'
  	@echo '  use "make tools/help"'
  	@echo '  or  "cd tools; make help"'
  	@echo  ''
  	@echo  'Kernel packaging:'
  	@$(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\
  " $(b) $(subst _defconfig,,$(b));) \
  		echo '')
  	@$(if $(board-dirs), \
  		$(foreach b, $(board-dirs), \
  		printf "  %-16s - Show %s-specific targets\
  " help-$(b) $(b);) \
  		printf "  %-16s - Show all of the above\
  " 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\
  " $*/$(b) $(subst _defconfig,,$(b));) \
  		echo '')
  
  
  # Documentation targets
  # ---------------------------------------------------------------------------
  DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs 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) \
  		\( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
  		-o -name '*.ko.*' \
  		-o -name '*.dwo'  \
  		-o -name '*.su'  \
  		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
  		-o -name '*.symtypes' -o -name 'modules.order' \
  		-o -name modules.builtin -o -name '.tmp_*.o.*' \
  		-o -name '*.c.[012]*.*' \
  		-o -name '*.ll' \
  		-o -name '*.gcno' \
  		-o -name '*.*.symversions' \) -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=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
  
  tools/%: FORCE
  	$(Q)mkdir -p $(objtree)/tools
  	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) 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)