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VERSION = 2
PATCHLEVEL = 6
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SUBLEVEL = 39
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EXTRAVERSION =
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NAME = Flesh-Eating Bats with Fangs
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# *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.

# Do not:
# o  use make's built-in rules and variables
#    (this increases performance and avoids hard-to-debug behaviour);
# o  print "Entering directory ...";
MAKEFLAGS += -rR --no-print-directory
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# Avoid funny character set dependencies
LC_COLLATE=C
LC_NUMERIC=C
export LC_COLLATE LC_NUMERIC
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# 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.

# 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)
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endif
ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
endif

# 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/sparse.txt" for more details, including
# where to get the "sparse" utility.
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ifeq ("$(origin C)", "command line")
  KBUILD_CHECKSRC = $(C)
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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
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# 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/"
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# 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 set on invocation of make in OBJ directory
# KBUILD_SRC is not intended to be used by the regular user (for now)
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)
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endif

ifeq ("$(origin W)", "command line")
  export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
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# That's our default target when none is given on the command line
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_all:

# Cancel implicit rules on top Makefile
$(CURDIR)/Makefile Makefile: ;

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ifneq ($(KBUILD_OUTPUT),)
# Invoke a second make in the output directory, passing relevant variables
# check that the output directory actually exists
saved-output := $(KBUILD_OUTPUT)
KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
$(if $(KBUILD_OUTPUT),, \
     $(error output directory "$(saved-output)" does not exist))

PHONY += $(MAKECMDGOALS) sub-make

$(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
	$(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
	KBUILD_SRC=$(CURDIR) \
	KBUILD_EXTMOD="$(KBUILD_EXTMOD)" -f $(CURDIR)/Makefile \
	$(filter-out _all sub-make,$(MAKECMDGOALS))
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# 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),)

# If building an external module we do not care about the all: rule
# but instead _all depend on modules
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ifeq ($(KBUILD_EXTMOD),)
_all: all
else
_all: modules
endif

srctree		:= $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
objtree		:= $(CURDIR)
src		:= $(srctree)
obj		:= $(objtree)

VPATH		:= $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
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export srctree objtree VPATH
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# 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/i386/ -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/ )
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# 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.
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# Default value for CROSS_COMPILE is not to prefix executables
# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
export KBUILD_BUILDHOST := $(SUBARCH)
ARCH		?= $(SUBARCH)
CROSS_COMPILE	?= $(CONFIG_CROSS_COMPILE:"%"=%)
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# Architecture as present in compile.h
UTS_MACHINE 	:= $(ARCH)
SRCARCH 	:= $(ARCH)
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# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
        SRCARCH := x86
endif
ifeq ($(ARCH),x86_64)
        SRCARCH := x86
endif
# Additional ARCH settings for sparc
ifeq ($(ARCH),sparc32)
       SRCARCH := sparc
endif
ifeq ($(ARCH),sparc64)
       SRCARCH := sparc
# Additional ARCH settings for sh
ifeq ($(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)

ifeq ($(ARCH),m68knommu)
       hdr-arch  := m68k
endif

KCONFIG_CONFIG	?= .config
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# 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)

HOSTCC       = gcc
HOSTCXX      = g++
HOSTCFLAGS   = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer
HOSTCXXFLAGS = -O2
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# Decide whether to build built-in, modular, or both.
# Normally, just do built-in.
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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.
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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
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export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD

# 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
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# the variable $(silent_cmd_cc_o_c) doesn't exist.
#
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# A simple variant is to prefix commands with $(Q) - that's useful
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# 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.

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 ($(findstring s,$(MAKEFLAGS)),)
  quiet=silent_
endif

export quiet Q KBUILD_VERBOSE


# Look for make include files relative to root of kernel src
MAKEFLAGS += --include-dir=$(srctree)

# We need some generic definitions (do not try to remake the file).
$(srctree)/scripts/Kbuild.include: ;
include $(srctree)/scripts/Kbuild.include
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# 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
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DEPMOD		= /sbin/depmod
KALLSYMS	= scripts/kallsyms
PERL		= perl
CHECK		= sparse

CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
		  -Wbitwise -Wno-return-void $(CF)
CFLAGS_MODULE   =
AFLAGS_MODULE   =
LDFLAGS_MODULE  =
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CFLAGS_KERNEL	=
AFLAGS_KERNEL	=
CFLAGS_GCOV	= -fprofile-arcs -ftest-coverage
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# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include \
                   -Iarch/$(hdr-arch)/include/generated -Iinclude \
                   $(if $(KBUILD_SRC), -I$(srctree)/include) \
                   -include include/generated/autoconf.h
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KBUILD_CPPFLAGS := -D__KERNEL__
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KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
		   -fno-strict-aliasing -fno-common \
		   -Werror-implicit-function-declaration \
		   -Wno-format-security \
		   -fno-delete-null-pointer-checks
KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
KBUILD_AFLAGS   := -D__ASSEMBLY__
KBUILD_AFLAGS_MODULE  := -DMODULE
KBUILD_CFLAGS_MODULE  := -DMODULE
KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
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# Read KERNELRELEASE from include/config/kernel.release (if it exists)
KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(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
export MAKE AWK GENKSYMS INSTALLKERNEL PERL UTS_MACHINE
export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
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export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV
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
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# 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

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
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# ===========================================================================
# Rules shared between *config targets and build targets

# Basic helpers built in scripts/
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scripts_basic:
	$(Q)$(MAKE) $(build)=scripts/basic
	$(Q)rm -f .tmp_quiet_recordmcount
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# To avoid any implicit rule to kick in, define an empty command.
scripts/basic/%: scripts_basic ;

# outputmakefile generates a Makefile in the output directory, if using a
# separate output directory. This allows convenient use of make in the
# output directory.
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outputmakefile:
ifneq ($(KBUILD_SRC),)
	$(Q)ln -fsn $(srctree) source
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
	    $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
endif
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# Support for using generic headers in asm-generic
PHONY += asm-generic
asm-generic:
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
	            obj=arch/$(SRCARCH)/include/generated/asm

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# 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'.
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# Detect when mixed targets is specified, and make a second invocation
# of make so .config is not included in this case either (for *config).

no-dot-config-targets := clean mrproper distclean \
			 cscope gtags TAGS tags help %docs check% coccicheck \
			 include/linux/version.h headers_% \
			 kernelversion %src-pkg
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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,$(MAKECMDGOALS)),)
                config-targets := 1
                ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
                        mixed-targets := 1
                endif
        endif
endif

ifeq ($(mixed-targets),1)
# ===========================================================================
# We're called with mixed targets (*config and build targets).
# Handle them one by one.

%:: FORCE
	$(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@

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 $(srctree)/arch/$(SRCARCH)/Makefile
export KBUILD_DEFCONFIG KBUILD_KCONFIG
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config: scripts_basic outputmakefile FORCE
	$(Q)mkdir -p include/linux include/config
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

%config: scripts_basic outputmakefile FORCE
	$(Q)mkdir -p include/linux include/config
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	$(Q)$(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
scripts: scripts_basic include/config/auto.conf include/config/tristate.conf
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	$(Q)$(MAKE) $(build)=$(@)

# Objects we will link into vmlinux / subdirs we need to visit
init-y		:= init/
drivers-y	:= drivers/ sound/ firmware/
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net-y		:= net/
libs-y		:= lib/
core-y		:= usr/
endif # KBUILD_EXTMOD

ifeq ($(dot-config),1)
# Read in config
-include include/config/auto.conf
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# Read in dependencies to all Kconfig* files, make sure to run
# oldconfig if changes are detected.
-include include/config/auto.conf.cmd
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# To avoid any implicit rule to kick in, define an empty command
$(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
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# 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
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	$(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
# 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;								\
	echo "  ERROR: Kernel configuration is invalid.";		\
	echo "         include/generated/autoconf.h or $@ are missing.";\
	echo "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
	echo;								\
	/bin/false)

endif # KBUILD_EXTMOD
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else
# Dummy target needed, because used as prerequisite
include/config/auto.conf: ;
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# 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
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all: vmlinux

ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
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else
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endif

include $(srctree)/arch/$(SRCARCH)/Makefile

ifneq ($(CONFIG_FRAME_WARN),0)
KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
endif

# Force gcc to behave correct even for buggy distributions
ifndef CONFIG_CC_STACKPROTECTOR
KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector)
# This warning generated too much noise in a regular build.
# Use make W=1 to enable this warning (see scripts/Makefile.build)
KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
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ifdef CONFIG_FRAME_POINTER
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
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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
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endif
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ifdef CONFIG_DEBUG_INFO
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endif

ifdef CONFIG_DEBUG_INFO_REDUCED
KBUILD_CFLAGS 	+= $(call cc-option, -femit-struct-debug-baseonly)
endif

ifdef CONFIG_FUNCTION_TRACER
ifdef CONFIG_DYNAMIC_FTRACE
		BUILD_C_RECORDMCOUNT := y
		export BUILD_C_RECORDMCOUNT
	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

# arch Makefile may override CC so keep this after arch Makefile is included
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
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# warn about C99 declaration after statement
KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
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# disable pointer signed / unsigned warnings in gcc 4.0
KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
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# 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)

# use the deterministic mode of AR if available
KBUILD_ARFLAGS := $(call ar-option,D)

# check for 'asm goto'
ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
	KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
endif

# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
# But warn user when we do so
warn-assign = \
$(warning "WARNING: Appending $$K$(1) ($(K$(1))) from $(origin K$(1)) to kernel $$$(1)")

ifneq ($(KCPPFLAGS),)
        $(call warn-assign,CPPFLAGS)
        KBUILD_CPPFLAGS += $(KCPPFLAGS)
endif
ifneq ($(KAFLAGS),)
        $(call warn-assign,AFLAGS)
        KBUILD_AFLAGS += $(KAFLAGS)
endif
ifneq ($(KCFLAGS),)
        $(call warn-assign,CFLAGS)
        KBUILD_CFLAGS += $(KCFLAGS)
endif
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# Use --build-id when available.
LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
			      $(call cc-ldoption, -Wl$(comma)--build-id,))
KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
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LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)

LDFLAGS_vmlinux	+= $(call ld-option, -X,)
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# Default kernel image to build when no specific target is given.
# KBUILD_IMAGE may be overruled on the command line or
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# set in the environment
# Also any assignments in arch/$(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_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)
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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
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

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ifeq ($(KBUILD_EXTMOD),)
core-y		+= kernel/ mm/ fs/ ipc/ security/ crypto/ block/
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vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
		     $(net-y) $(net-m) $(libs-y) $(libs-m)))

vmlinux-alldirs	:= $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
		     $(init-n) $(init-) \
		     $(core-n) $(core-) $(drivers-n) $(drivers-) \
		     $(net-n)  $(net-)  $(libs-n)    $(libs-))))

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		:= $(patsubst %/, %/built-in.o, $(libs-y))
libs-y		:= $(libs-y1) $(libs-y2)

# Build vmlinux
# ---------------------------------------------------------------------------
# vmlinux is built from the objects selected by $(vmlinux-init) and
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# $(vmlinux-main). Most are built-in.o files from top-level directories
# in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
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# Ordering when linking is important, and $(vmlinux-init) must be first.
#
# vmlinux
#   ^
#   |
#   +-< $(vmlinux-init)
#   |   +--< init/version.o + more
#   |
#   +--< $(vmlinux-main)
#   |    +--< driver/built-in.o mm/built-in.o + more
#   |
#   +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
#
# vmlinux version (uname -v) cannot be updated during normal
# descending-into-subdirs phase since we do not yet know if we need to
# update vmlinux.
# Therefore this step is delayed until just before final link of vmlinux -
# except in the kallsyms case where it is done just before adding the
# symbols to the kernel.
#
# System.map is generated to document addresses of all kernel symbols

vmlinux-init := $(head-y) $(init-y)
vmlinux-main := $(core-y) $(libs-y) $(drivers-y) $(net-y)
vmlinux-all  := $(vmlinux-init) $(vmlinux-main)
vmlinux-lds  := arch/$(SRCARCH)/kernel/vmlinux.lds
export KBUILD_VMLINUX_OBJS := $(vmlinux-all)
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# Rule to link vmlinux - also used during CONFIG_KALLSYMS
# May be overridden by arch/$(ARCH)/Makefile
quiet_cmd_vmlinux__ ?= LD      $@
      cmd_vmlinux__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) -o $@ \
      -T $(vmlinux-lds) $(vmlinux-init)                          \
      --start-group $(vmlinux-main) --end-group                  \
      $(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o FORCE ,$^)
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# Generate new vmlinux version
quiet_cmd_vmlinux_version = GEN     .version
      cmd_vmlinux_version = set -e;                     \
	if [ ! -r .version ]; then			\
	  rm -f .version;				\
	  echo 1 >.version;				\
	else						\
	  mv .version .old_version;			\
	  expr 0$$(cat .old_version) + 1 >.version;	\
	fi;						\
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	$(MAKE) $(build)=init

# Generate System.map
quiet_cmd_sysmap = SYSMAP
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      cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap

# Link of vmlinux
# If CONFIG_KALLSYMS is set .version is already updated
# Generate System.map and verify that the content is consistent
# Use + in front of the vmlinux_version rule to silent warning with make -j2
# First command is ':' to allow us to use + in front of the rule
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define rule_vmlinux__
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	$(if $(CONFIG_KALLSYMS),,+$(call cmd,vmlinux_version))

	$(call cmd,vmlinux__)
	$(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd

	$(Q)$(if $($(quiet)cmd_sysmap),                                      \
	  echo '  $($(quiet)cmd_sysmap)  System.map' &&)                     \
	$(cmd_sysmap) $@ System.map;                                         \
	if [ $$? -ne 0 ]; then                                               \
		rm -f $@;                                                    \
		/bin/false;                                                  \
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	fi;
	$(verify_kallsyms)
endef


ifdef CONFIG_KALLSYMS
# Generate section listing all symbols and add it into vmlinux $(kallsyms.o)
# It's a three stage process:
# o .tmp_vmlinux1 has all symbols and sections, but __kallsyms is
#   empty
#   Running kallsyms on that gives us .tmp_kallsyms1.o with
#   the right size - vmlinux version (uname -v) is updated during this step
# o .tmp_vmlinux2 now has a __kallsyms section of the right size,
#   but due to the added section, some addresses have shifted.
#   From here, we generate a correct .tmp_kallsyms2.o
# o The correct .tmp_kallsyms2.o is linked into the final vmlinux.
# o Verify that the System.map from vmlinux matches the map from
#   .tmp_vmlinux2, just in case we did not generate kallsyms correctly.
# o If 'make KALLSYMS_EXTRA_PASS=1" was used, do an extra pass using
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#   .tmp_vmlinux3 and .tmp_kallsyms3.o.  This is only meant as a
#   temporary bypass to allow the kernel to be built while the
#   maintainers work out what went wrong with kallsyms.

last_kallsyms := 2

ifdef KALLSYMS_EXTRA_PASS
ifneq ($(KALLSYMS_EXTRA_PASS),0)
last_kallsyms := 3
endif
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endif

kallsyms.o := .tmp_kallsyms$(last_kallsyms).o

define verify_kallsyms
	$(Q)$(if $($(quiet)cmd_sysmap),                                      \
	  echo '  $($(quiet)cmd_sysmap)  .tmp_System.map' &&)                \
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	  $(cmd_sysmap) .tmp_vmlinux$(last_kallsyms) .tmp_System.map
	$(Q)cmp -s System.map .tmp_System.map ||                             \
		(echo Inconsistent kallsyms data;                            \
		 echo This is a bug - please report about it;                \
		 echo Try "make KALLSYMS_EXTRA_PASS=1" as a workaround;      \
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		 rm .tmp_kallsyms* ; /bin/false )
endef

# Update vmlinux version before link
# Use + in front of this rule to silent warning about make -j1
# First command is ':' to allow us to use + in front of this rule
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cmd_ksym_ld = $(cmd_vmlinux__)
define rule_ksym_ld
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	+$(call cmd,vmlinux_version)
	$(call cmd,vmlinux__)
	$(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
endef

# Generate .S file with all kernel symbols
quiet_cmd_kallsyms = KSYM    $@
      cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
                     $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
.tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
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	$(call if_changed_dep,as_o_S)

.tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
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	$(call cmd,kallsyms)

# .tmp_vmlinux1 must be complete except kallsyms, so update vmlinux version
.tmp_vmlinux1: $(vmlinux-lds) $(vmlinux-all) FORCE
	$(call if_changed_rule,ksym_ld)
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.tmp_vmlinux2: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms1.o FORCE
	$(call if_changed,vmlinux__)
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.tmp_vmlinux3: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms2.o FORCE
	$(call if_changed,vmlinux__)
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# Needs to visit scripts/ before $(KALLSYMS) can be used.
$(KALLSYMS): scripts ;

# Generate some data for debugging strange kallsyms problems
debug_kallsyms: .tmp_map$(last_kallsyms)

.tmp_map%: .tmp_vmlinux% FORCE
	($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@

.tmp_map3: .tmp_map2

.tmp_map2: .tmp_map1

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endif # ifdef CONFIG_KALLSYMS

# Do modpost on a prelinked vmlinux. The finally linked vmlinux has
# relevant sections renamed as per the linker script.
quiet_cmd_vmlinux-modpost = LD      $@
      cmd_vmlinux-modpost = $(LD) $(LDFLAGS) -r -o $@                          \
	 $(vmlinux-init) --start-group $(vmlinux-main) --end-group             \
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	 $(filter-out $(vmlinux-init) $(vmlinux-main) FORCE ,$^)
define rule_vmlinux-modpost
	:
	+$(call cmd,vmlinux-modpost)
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $@
	$(Q)echo 'cmd_$@ := $(cmd_vmlinux-modpost)' > $(dot-target).cmd
endef

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# vmlinux image - including updated kernel symbols
vmlinux: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o $(kallsyms.o) FORCE
	$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
endif
ifdef CONFIG_SAMPLES
	$(Q)$(MAKE) $(build)=samples
endif
ifdef CONFIG_BUILD_DOCSRC
	$(Q)$(MAKE) $(build)=Documentation
	$(call vmlinux-modpost)
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	$(call if_changed_rule,vmlinux__)
	$(Q)rm -f .old_version
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# build vmlinux.o first to catch section mismatch errors early
ifdef CONFIG_KALLSYMS
.tmp_vmlinux1: vmlinux.o
endif
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modpost-init := $(filter-out init/built-in.o, $(vmlinux-init))
vmlinux.o: $(modpost-init) $(vmlinux-main) FORCE
	$(call if_changed_rule,vmlinux-modpost)

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# The actual objects are generated when descending, 
# make sure no implicit rule kicks in
$(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(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

$(vmlinux-dirs): prepare scripts
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	$(Q)$(MAKE) $(build)=$@

# Store (new) KERNELRELASE string in include/config/kernel.release
include/config/kernel.release: include/config/auto.conf FORCE
	$(Q)echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))" > $@
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# 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.
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# 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,
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# and if so do:
# 1) Check that make has not been executed in the kernel src $(srctree)
prepare3: include/config/kernel.release
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ifneq ($(KBUILD_SRC),)
	@$(kecho) '  Using $(srctree) as source for kernel'
	$(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
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		echo "  $(srctree) is not clean, please run 'make mrproper'";\
		echo "  in the '$(srctree)' directory.";\
		/bin/false; \
	fi;
endif

# prepare2 creates a makefile if using a separate output directory
prepare2: prepare3 outputmakefile asm-generic
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prepare1: prepare2 include/linux/version.h include/generated/utsrelease.h \
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                   include/config/auto.conf
	$(cmd_crmodverdir)
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archprepare: prepare1 scripts_basic

prepare0: archprepare FORCE
	$(Q)$(MAKE) $(build)=.
	$(Q)$(MAKE) $(build)=. missing-syscalls
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# All the preparing..
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# 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;    \