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# SPDX-License-Identifier: GPL-2.0
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VERSION = 5
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PATCHLEVEL = 7
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SUBLEVEL = 7
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EXTRAVERSION =
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NAME = Kleptomaniac Octopus
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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.

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# That's our default target when none is given on the command line
PHONY := _all
_all:

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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
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# unavoidable when linking the built-in.a targets which finally
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# 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.

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ifneq ($(sub_make_done),1)
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# Do not use make's built-in rules and variables
# (this increases performance and avoids hard-to-debug behaviour)
MAKEFLAGS += -rR

# 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

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# 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.
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# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
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#
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# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands

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ifeq ("$(origin V)", "command line")
  KBUILD_VERBOSE = $(V)
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endif
ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
endif

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ifeq ($(KBUILD_VERBOSE),1)
  quiet =
  Q =
else
  quiet=quiet_
  Q = @
endif

# If the user is running make -s (silent mode), suppress echoing of
# commands

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ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
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  quiet=silent_
endif

export quiet Q KBUILD_VERBOSE

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# Kbuild will save output files in the current working directory.
# This does not need to match to the root of the kernel source tree.
#
# For example, you can do this:
#
#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
#
# If you want to save output files in a different location, there are
# two syntaxes to specify it.
#
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# 1) O=
# Use "make O=dir/to/store/output/files/"
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#
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# 2) Set KBUILD_OUTPUT
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# Set the environment variable KBUILD_OUTPUT to point to the output directory.
# export KBUILD_OUTPUT=dir/to/store/output/files/; make
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#
# The O= assignment takes precedence over the KBUILD_OUTPUT environment
# variable.

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# Do we want to change the working directory?
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ifeq ("$(origin O)", "command line")
  KBUILD_OUTPUT := $(O)
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endif

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ifneq ($(KBUILD_OUTPUT),)
# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
# expand a shell special character '~'. We use a somewhat tedious way here.
abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
$(if $(abs_objtree),, \
     $(error failed to create output directory "$(KBUILD_OUTPUT)"))

# $(realpath ...) resolves symlinks
abs_objtree := $(realpath $(abs_objtree))
else
abs_objtree := $(CURDIR)
endif # ifneq ($(KBUILD_OUTPUT),)

ifeq ($(abs_objtree),$(CURDIR))
# Suppress "Entering directory ..." unless we are changing the work directory.
MAKEFLAGS += --no-print-directory
else
need-sub-make := 1
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endif

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abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
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ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
$(error source directory cannot contain spaces or colons)
endif
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ifneq ($(abs_srctree),$(abs_objtree))
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# Look for make include files relative to root of kernel src
#
# This does not become effective immediately because MAKEFLAGS is re-parsed
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# once after the Makefile is read. We need to invoke sub-make.
MAKEFLAGS += --include-dir=$(abs_srctree)
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need-sub-make := 1
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endif
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ifneq ($(filter 3.%,$(MAKE_VERSION)),)
# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
# We need to invoke sub-make to avoid implicit rules in the top Makefile.
need-sub-make := 1
# Cancel implicit rules for this Makefile.
$(lastword $(MAKEFILE_LIST)): ;
endif

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export abs_srctree abs_objtree
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export sub_make_done := 1

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ifeq ($(need-sub-make),1)

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PHONY += $(MAKECMDGOALS) sub-make

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$(filter-out _all sub-make $(lastword $(MAKEFILE_LIST)), $(MAKECMDGOALS)) _all: sub-make
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	@:
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# Invoke a second make in the output directory, passing relevant variables
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sub-make:
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	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
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endif # need-sub-make
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endif # sub_make_done
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# We process the rest of the Makefile if this is the final invocation of make
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ifeq ($(need-sub-make),)
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# 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

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# 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.
#
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# See the file "Documentation/dev-tools/sparse.rst" for more details,
# including where to get the "sparse" utility.
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ifeq ("$(origin C)", "command line")
  KBUILD_CHECKSRC = $(C)
endif
ifndef KBUILD_CHECKSRC
  KBUILD_CHECKSRC = 0
endif

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# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
# directory of external module to build. Setting M= takes precedence.
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ifeq ("$(origin M)", "command line")
  KBUILD_EXTMOD := $(M)
endif

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export KBUILD_CHECKSRC KBUILD_EXTMOD

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extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)

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ifeq ($(abs_srctree),$(abs_objtree))
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        # building in the source tree
        srctree := .
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	building_out_of_srctree :=
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else
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        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
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                # building in a subdirectory of the source tree
                srctree := ..
        else
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                srctree := $(abs_srctree)
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        endif
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	building_out_of_srctree := 1
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endif
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ifneq ($(KBUILD_ABS_SRCTREE),)
srctree := $(abs_srctree)
endif
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objtree		:= .
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VPATH		:= $(srctree)
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export building_out_of_srctree srctree objtree VPATH
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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'.
# 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

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clean-targets := %clean mrproper cleandocs
no-dot-config-targets := $(clean-targets) \
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			 cscope gtags TAGS tags help% %docs check% coccicheck \
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			 $(version_h) headers headers_% archheaders archscripts \
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			 %asm-generic kernelversion %src-pkg dt_binding_check \
			 outputmakefile
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no-sync-config-targets := $(no-dot-config-targets) install %install \
			   kernelrelease
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single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
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config-build	:=
mixed-build	:=
need-config	:= 1
may-sync-config	:= 1
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single-build	:=
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ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
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		need-config :=
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	endif
endif

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ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
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		may-sync-config :=
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	endif
endif

ifneq ($(KBUILD_EXTMOD),)
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	may-sync-config :=
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endif

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ifeq ($(KBUILD_EXTMOD),)
        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
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		config-build := 1
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                ifneq ($(words $(MAKECMDGOALS)),1)
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			mixed-build := 1
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                endif
        endif
endif
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# We cannot build single targets and the others at the same time
ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
	single-build := 1
	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
		mixed-build := 1
	endif
endif

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# For "make -j clean all", "make -j mrproper defconfig all", etc.
ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
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		mixed-build := 1
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        endif
endif

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# install and modules_install need also be processed one by one
ifneq ($(filter install,$(MAKECMDGOALS)),)
        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
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		mixed-build := 1
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        endif
endif

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ifdef mixed-build
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# ===========================================================================
# 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

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else # !mixed-build
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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

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include scripts/subarch.include
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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.
# Default value for CROSS_COMPILE is not to prefix executables
# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
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ARCH		?= $(SUBARCH)
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# Architecture as present in compile.h
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UTS_MACHINE 	:= $(ARCH)
SRCARCH 	:= $(ARCH)
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# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
        SRCARCH := x86
endif
ifeq ($(ARCH),x86_64)
        SRCARCH := x86
endif
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# Additional ARCH settings for sparc
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ifeq ($(ARCH),sparc32)
       SRCARCH := sparc
endif
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ifeq ($(ARCH),sparc64)
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       SRCARCH := sparc
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endif
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# Additional ARCH settings for sh
ifeq ($(ARCH),sh64)
       SRCARCH := sh
endif

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KCONFIG_CONFIG	?= .config
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export KCONFIG_CONFIG
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# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
export KBUILD_DEFCONFIG := defconfig

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# SHELL used by kbuild
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CONFIG_SHELL := sh
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HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
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ifneq ($(LLVM),)
HOSTCC	= clang
HOSTCXX	= clang++
else
HOSTCC	= gcc
HOSTCXX	= g++
endif
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KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
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		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
		$(HOSTCFLAGS)
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KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
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KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
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# Make variables (CC, etc...)
CPP		= $(CC) -E
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ifneq ($(LLVM),)
CC		= clang
LD		= ld.lld
AR		= llvm-ar
NM		= llvm-nm
OBJCOPY		= llvm-objcopy
OBJDUMP		= llvm-objdump
READELF		= llvm-readelf
OBJSIZE		= llvm-size
STRIP		= llvm-strip
else
CC		= $(CROSS_COMPILE)gcc
LD		= $(CROSS_COMPILE)ld
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AR		= $(CROSS_COMPILE)ar
NM		= $(CROSS_COMPILE)nm
OBJCOPY		= $(CROSS_COMPILE)objcopy
OBJDUMP		= $(CROSS_COMPILE)objdump
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READELF		= $(CROSS_COMPILE)readelf
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OBJSIZE		= $(CROSS_COMPILE)size
STRIP		= $(CROSS_COMPILE)strip
endif
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PAHOLE		= pahole
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LEX		= flex
YACC		= bison
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AWK		= awk
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INSTALLKERNEL  := installkernel
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DEPMOD		= /sbin/depmod
PERL		= perl
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PYTHON		= python
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PYTHON3		= python3
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CHECK		= sparse
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BASH		= bash
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CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
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		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
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NOSTDINC_FLAGS :=
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CFLAGS_MODULE   =
AFLAGS_MODULE   =
LDFLAGS_MODULE  =
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CFLAGS_KERNEL	=
AFLAGS_KERNEL	=
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LDFLAGS_vmlinux =
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# Use USERINCLUDE when you must reference the UAPI directories only.
USERINCLUDE    := \
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		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
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		-I$(srctree)/include/uapi \
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		-I$(objtree)/include/generated/uapi \
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                -include $(srctree)/include/linux/kconfig.h

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# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
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LINUXINCLUDE    := \
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		-I$(srctree)/arch/$(SRCARCH)/include \
		-I$(objtree)/arch/$(SRCARCH)/include/generated \
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		$(if $(building_out_of_srctree),-I$(srctree)/include) \
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		-I$(objtree)/include \
		$(USERINCLUDE)
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KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
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KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
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		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
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		   -Werror=implicit-function-declaration -Werror=implicit-int \
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		   -Wno-format-security \
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		   -std=gnu89
KBUILD_CPPFLAGS := -D__KERNEL__
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KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
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KBUILD_AFLAGS_MODULE  := -DMODULE
KBUILD_CFLAGS_MODULE  := -DMODULE
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KBUILD_LDFLAGS_MODULE :=
export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
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KBUILD_LDFLAGS :=
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GCC_PLUGINS_CFLAGS :=
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CLANG_FLAGS :=
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export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
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export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
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export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
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export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
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export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
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export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
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export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
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export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
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export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
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# Files to ignore in find ... statements

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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
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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

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# Basic helpers built in scripts/basic/
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PHONY += scripts_basic
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scripts_basic:
	$(Q)$(MAKE) $(build)=scripts/basic
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	$(Q)rm -f .tmp_quiet_recordmcount
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PHONY += outputmakefile
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# Before starting out-of-tree build, make sure the source tree is clean.
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# 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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# At the same time when output Makefile generated, generate .gitignore to
# ignore whole output directory
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outputmakefile:
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ifdef building_out_of_srctree
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	$(Q)if [ -f $(srctree)/.config -o \
		 -d $(srctree)/include/config -o \
		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
		echo >&2 "***"; \
		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
		echo >&2 "*** in $(abs_srctree)";\
		echo >&2 "***"; \
		false; \
	fi
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	$(Q)ln -fsn $(srctree) source
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	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
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	$(Q)test -e .gitignore || \
	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
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endif
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ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
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ifneq ($(CROSS_COMPILE),)
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CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
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GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
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CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
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GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
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endif
ifneq ($(GCC_TOOLCHAIN),)
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CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
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endif
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ifneq ($(LLVM_IAS),1)
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CLANG_FLAGS	+= -no-integrated-as
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endif
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CLANG_FLAGS	+= -Werror=unknown-warning-option
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KBUILD_CFLAGS	+= $(CLANG_FLAGS)
KBUILD_AFLAGS	+= $(CLANG_FLAGS)
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export CLANG_FLAGS
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endif

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# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
# and from include/config/auto.conf.cmd to detect the compiler upgrade.
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CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
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ifdef config-build
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# ===========================================================================
# *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'
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include arch/$(SRCARCH)/Makefile
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export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
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config: outputmakefile scripts_basic FORCE
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	$(Q)$(MAKE) $(build)=scripts/kconfig $@

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%config: outputmakefile scripts_basic FORCE
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	$(Q)$(MAKE) $(build)=scripts/kconfig $@

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else #!config-build
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# ===========================================================================
# Build targets only - this includes vmlinux, arch specific targets, clean
# targets and others. In general all targets except *config targets.

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# 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.
ifeq ($(MAKECMDGOALS),modules)
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  KBUILD_BUILTIN :=
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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

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ifneq ($(filter all _all modules nsdeps,$(MAKECMDGOALS)),)
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  KBUILD_MODULES := 1
endif

ifeq ($(MAKECMDGOALS),)
  KBUILD_MODULES := 1
endif

export KBUILD_MODULES KBUILD_BUILTIN

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ifdef need-config
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include include/config/auto.conf
endif

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ifeq ($(KBUILD_EXTMOD),)
# Objects we will link into vmlinux / subdirs we need to visit
init-y		:= init/
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drivers-y	:= drivers/ sound/
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drivers-$(CONFIG_SAMPLES) += samples/
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net-y		:= net/
libs-y		:= lib/
core-y		:= usr/
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virt-y		:= virt/
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endif # KBUILD_EXTMOD

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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
all: vmlinux

CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
	$(call cc-option,-fno-tree-loop-im) \
	$(call cc-disable-warning,maybe-uninitialized,)
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export CFLAGS_GCOV
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# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
ifdef CONFIG_FUNCTION_TRACER
  CC_FLAGS_FTRACE := -pg
endif

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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

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include arch/$(SRCARCH)/Makefile
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ifdef need-config
ifdef may-sync-config
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# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
# because some architectures define CROSS_COMPILE there.
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include include/config/auto.conf.cmd
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$(KCONFIG_CONFIG):
	@echo >&2 '***'
	@echo >&2 '*** Configuration file "$@" not found!'
	@echo >&2 '***'
	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
	@echo >&2 '*** "make menuconfig" or "make xconfig").'
	@echo >&2 '***'
	@/bin/false
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# The actual configuration files used during the build are stored in
# include/generated/ and include/config/. Update them if .config is newer than
# include/config/auto.conf (which mirrors .config).
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#
# This exploits the 'multi-target pattern rule' trick.
# The syncconfig should be executed only once to make all the targets.
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# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
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%/auto.conf %/auto.conf.cmd: $(KCONFIG_CONFIG)
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	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
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else # !may-sync-config
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# External modules and some install targets need 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
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PHONY += include/config/auto.conf

include/config/auto.conf:
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	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
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	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 ;							\
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	/bin/false)

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endif # may-sync-config
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endif # need-config
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KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
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KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
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KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
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KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
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ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
KBUILD_CFLAGS += -O2
else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
KBUILD_CFLAGS += -O3
else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
KBUILD_CFLAGS += -Os
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endif
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# Tell gcc to never replace conditional load with a non-conditional one
KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
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KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
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include scripts/Makefile.kcov
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include scripts/Makefile.gcc-plugins

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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

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ifneq ($(CONFIG_FRAME_WARN),0)
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KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
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endif

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stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
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stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
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KBUILD_CFLAGS += $(stackp-flags-y)
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ifdef CONFIG_CC_IS_CLANG
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KBUILD_CPPFLAGS += -Qunused-arguments
KBUILD_CFLAGS += -Wno-format-invalid-specifier
KBUILD_CFLAGS += -Wno-gnu
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# 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
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KBUILD_CFLAGS += -mno-global-merge
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else

# These warnings generated too much noise in a regular build.
# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
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KBUILD_CFLAGS += -Wno-unused-but-set-variable
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# Warn about unmarked fall-throughs in switch statement.
# Disabled for clang while comment to attribute conversion happens and
# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
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endif

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KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
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ifdef CONFIG_FRAME_POINTER
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KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
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else
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# 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
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KBUILD_CFLAGS	+= -fomit-frame-pointer
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endif
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endif
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# Initialize all stack variables with a pattern, if desired.
ifdef CONFIG_INIT_STACK_ALL
KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
endif

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DEBUG_CFLAGS	:= $(call cc-option, -fno-var-tracking-assignments)
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ifdef CONFIG_DEBUG_INFO
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ifdef CONFIG_DEBUG_INFO_SPLIT
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DEBUG_CFLAGS	+= -gsplit-dwarf
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else
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DEBUG_CFLAGS	+= -g
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endif
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KBUILD_AFLAGS	+= -Wa,-gdwarf-2
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endif
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ifdef CONFIG_DEBUG_INFO_DWARF4
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DEBUG_CFLAGS	+= -gdwarf-4
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endif
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ifdef CONFIG_DEBUG_INFO_REDUCED
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DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
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		   $(call cc-option,-fno-var-tracking)
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endif

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KBUILD_CFLAGS += $(DEBUG_CFLAGS)
export DEBUG_CFLAGS

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ifdef CONFIG_FUNCTION_TRACER
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ifdef CONFIG_FTRACE_MCOUNT_RECORD
  # gcc 5 supports generating the mcount tables directly
  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
    CC_FLAGS_FTRACE	+= -mrecord-mcount
    export CC_USING_RECORD_MCOUNT := 1
  endif
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  ifdef CONFIG_HAVE_NOP_MCOUNT
    ifeq ($(call cc-option-yn, -mnop-mcount),y)
      CC_FLAGS_FTRACE	+= -mnop-mcount
      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
    endif
  endif
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endif
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ifdef CONFIG_HAVE_FENTRY
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  ifeq ($(call cc-option-yn, -mfentry),y)
    CC_FLAGS_FTRACE	+= -mfentry
    CC_FLAGS_USING	+= -DCC_USING_FENTRY
  endif
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endif
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export CC_FLAGS_FTRACE
KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
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ifdef CONFIG_DYNAMIC_FTRACE
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	ifdef CONFIG_HAVE_C_RECORDMCOUNT
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		BUILD_C_RECORDMCOUNT := y
		export BUILD_C_RECORDMCOUNT
	endif
endif
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endif

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# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
endif

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ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
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KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
LDFLAGS_vmlinux += --gc-sections
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endif

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ifdef CONFIG_LIVEPATCH
KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
endif

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# arch Makefile may override CC so keep this after arch Makefile is included
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NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
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# warn about C99 declaration after statement
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KBUILD_CFLAGS += -Wdeclaration-after-statement
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# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
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KBUILD_CFLAGS += -Wvla
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# disable pointer signed / unsigned warnings in gcc 4.0
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KBUILD_CFLAGS += -Wno-pointer-sign
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# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

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# We'll want to enable this eventually, but it's not going away for 5.7 at least
KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
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KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
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KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
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# Another good warning that we'll want to enable eventually
KBUILD_CFLAGS += $(call cc-disable-warning, restrict)

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# Enabled with W=2, disabled by default as noisy
KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)

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# disable invalid "can't wrap" optimizations for signed / pointers
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KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
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# 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)

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# Make sure -fstack-check isn't enabled (like gentoo apparently did)
KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)

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# conserve stack if available
KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)

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# Prohibit date/time macros, which would make the build non-deterministic
KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)

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# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

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# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

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# change __FILE__ to the relative path from the srctree
KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)

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# ensure -fcf-protection is disabled when using retpoline as it is
# incompatible with -mindirect-branch=thunk-extern
ifdef CONFIG_RETPOLINE
KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
endif

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include scripts/Makefile.kasan
include scripts/Makefile.extrawarn
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include scripts/Makefile.ubsan
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# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS   += $(KAFLAGS)
KBUILD_CFLAGS   += $(KCFLAGS)
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KBUILD_LDFLAGS_MODULE += --build-id
LDFLAGS_vmlinux += --build-id
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