8 # To see a list of typical targets execute "make help"
9 # More info can be located in ./README
10 # Comments in this file are targeted only to the developer, do not
11 # expect to learn how to build the kernel reading this file.
13 # o Do not use make's built-in rules and variables
14 # (this increases performance and avoids hard-to-debug behaviour);
15 # o Look for make include files relative to root of kernel src
16 MAKEFLAGS += -rR --include-dir=$(CURDIR)
18 # Avoid funny character set dependencies
22 export LC_COLLATE LC_NUMERIC
24 # Avoid interference with shell env settings
27 # We are using a recursive build, so we need to do a little thinking
28 # to get the ordering right.
30 # Most importantly: sub-Makefiles should only ever modify files in
31 # their own directory. If in some directory we have a dependency on
32 # a file in another dir (which doesn't happen often, but it's often
33 # unavoidable when linking the built-in.o targets which finally
34 # turn into vmlinux), we will call a sub make in that other dir, and
35 # after that we are sure that everything which is in that other dir
38 # The only cases where we need to modify files which have global
39 # effects are thus separated out and done before the recursive
40 # descending is started. They are now explicitly listed as the
44 # ---------------------------------------------------------------------------
46 # Normally, we echo the whole command before executing it. By making
47 # that echo $($(quiet)$(cmd)), we now have the possibility to set
48 # $(quiet) to choose other forms of output instead, e.g.
50 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
51 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
53 # If $(quiet) is empty, the whole command will be printed.
54 # If it is set to "quiet_", only the short version will be printed.
55 # If it is set to "silent_", nothing will be printed at all, since
56 # the variable $(silent_cmd_cc_o_c) doesn't exist.
58 # A simple variant is to prefix commands with $(Q) - that's useful
59 # for commands that shall be hidden in non-verbose mode.
63 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
64 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
66 # To put more focus on warnings, be less verbose as default
67 # Use 'make V=1' to see the full commands
69 ifeq ("$(origin V)", "command line")
76 ifeq ($(KBUILD_VERBOSE),1)
84 # If the user is running make -s (silent mode), suppress echoing of
87 ifneq ($(filter 4.%,$(MAKE_VERSION)),) # make-4
88 ifneq ($(filter %s ,$(firstword x$(MAKEFLAGS))),)
93 ifneq ($(filter s% -s%,$(MAKEFLAGS)),)
99 export quiet Q KBUILD_VERBOSE
101 # kbuild supports saving output files in a separate directory.
102 # To locate output files in a separate directory two syntaxes are supported.
103 # In both cases the working directory must be the root of the kernel src.
105 # Use "make O=dir/to/store/output/files/"
107 # 2) Set KBUILD_OUTPUT
108 # Set the environment variable KBUILD_OUTPUT to point to the directory
109 # where the output files shall be placed.
110 # export KBUILD_OUTPUT=dir/to/store/output/files/
113 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
116 # KBUILD_SRC is set on invocation of make in OBJ directory
117 # KBUILD_SRC is not intended to be used by the regular user (for now)
118 ifeq ($(KBUILD_SRC),)
120 # OK, Make called in directory where kernel src resides
121 # Do we want to locate output files in a separate directory?
122 ifeq ("$(origin O)", "command line")
123 KBUILD_OUTPUT := $(O)
126 # That's our default target when none is given on the command line
130 # Cancel implicit rules on top Makefile
131 $(CURDIR)/Makefile Makefile: ;
133 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
134 $(error main directory cannot contain spaces nor colons)
137 ifneq ($(KBUILD_OUTPUT),)
138 # Invoke a second make in the output directory, passing relevant variables
139 # check that the output directory actually exists
140 saved-output := $(KBUILD_OUTPUT)
141 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
143 $(if $(KBUILD_OUTPUT),, \
144 $(error failed to create output directory "$(saved-output)"))
146 PHONY += $(MAKECMDGOALS) sub-make
148 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
152 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
153 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
155 # Leave processing to above invocation of make
157 endif # ifneq ($(KBUILD_OUTPUT),)
158 endif # ifeq ($(KBUILD_SRC),)
160 # We process the rest of the Makefile if this is the final invocation of make
161 ifeq ($(skip-makefile),)
163 # Do not print "Entering directory ...",
164 # but we want to display it when entering to the output directory
165 # so that IDEs/editors are able to understand relative filenames.
166 MAKEFLAGS += --no-print-directory
168 # Call a source code checker (by default, "sparse") as part of the
171 # Use 'make C=1' to enable checking of only re-compiled files.
172 # Use 'make C=2' to enable checking of *all* source files, regardless
173 # of whether they are re-compiled or not.
175 # See the file "Documentation/sparse.txt" for more details, including
176 # where to get the "sparse" utility.
178 ifeq ("$(origin C)", "command line")
179 KBUILD_CHECKSRC = $(C)
181 ifndef KBUILD_CHECKSRC
185 # Use make M=dir to specify directory of external module to build
186 # Old syntax make ... SUBDIRS=$PWD is still supported
187 # Setting the environment variable KBUILD_EXTMOD take precedence
189 KBUILD_EXTMOD ?= $(SUBDIRS)
192 ifeq ("$(origin M)", "command line")
193 KBUILD_EXTMOD := $(M)
196 # If building an external module we do not care about the all: rule
197 # but instead _all depend on modules
199 ifeq ($(KBUILD_EXTMOD),)
205 ifeq ($(KBUILD_SRC),)
206 # building in the source tree
209 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
210 # building in a subdirectory of the source tree
213 srctree := $(KBUILD_SRC)
220 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
222 export srctree objtree VPATH
224 # SUBARCH tells the usermode build what the underlying arch is. That is set
225 # first, and if a usermode build is happening, the "ARCH=um" on the command
226 # line overrides the setting of ARCH below. If a native build is happening,
227 # then ARCH is assigned, getting whatever value it gets normally, and
228 # SUBARCH is subsequently ignored.
230 SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
231 -e s/sun4u/sparc64/ \
232 -e s/arm.*/arm/ -e s/sa110/arm/ \
233 -e s/s390x/s390/ -e s/parisc64/parisc/ \
234 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
235 -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
237 # Cross compiling and selecting different set of gcc/bin-utils
238 # ---------------------------------------------------------------------------
240 # When performing cross compilation for other architectures ARCH shall be set
241 # to the target architecture. (See arch/* for the possibilities).
242 # ARCH can be set during invocation of make:
244 # Another way is to have ARCH set in the environment.
245 # The default ARCH is the host where make is executed.
247 # CROSS_COMPILE specify the prefix used for all executables used
248 # during compilation. Only gcc and related bin-utils executables
249 # are prefixed with $(CROSS_COMPILE).
250 # CROSS_COMPILE can be set on the command line
251 # make CROSS_COMPILE=ia64-linux-
252 # Alternatively CROSS_COMPILE can be set in the environment.
253 # A third alternative is to store a setting in .config so that plain
254 # "make" in the configured kernel build directory always uses that.
255 # Default value for CROSS_COMPILE is not to prefix executables
256 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
258 CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)
260 # Architecture as present in compile.h
261 UTS_MACHINE := $(ARCH)
264 # Additional ARCH settings for x86
268 ifeq ($(ARCH),x86_64)
272 # Additional ARCH settings for sparc
273 ifeq ($(ARCH),sparc32)
276 ifeq ($(ARCH),sparc64)
280 # Additional ARCH settings for sh
285 # Additional ARCH settings for tile
286 ifeq ($(ARCH),tilepro)
289 ifeq ($(ARCH),tilegx)
293 # Where to locate arch specific headers
294 hdr-arch := $(SRCARCH)
296 KCONFIG_CONFIG ?= .config
297 export KCONFIG_CONFIG
299 # SHELL used by kbuild
300 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
301 else if [ -x /bin/bash ]; then echo /bin/bash; \
302 else echo sh; fi ; fi)
306 HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89
309 ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)
310 HOSTCFLAGS += -Wno-unused-value -Wno-unused-parameter \
311 -Wno-missing-field-initializers -fno-delete-null-pointer-checks
314 # Decide whether to build built-in, modular, or both.
315 # Normally, just do built-in.
320 # If we have only "make modules", don't compile built-in objects.
321 # When we're building modules with modversions, we need to consider
322 # the built-in objects during the descend as well, in order to
323 # make sure the checksums are up to date before we record them.
325 ifeq ($(MAKECMDGOALS),modules)
326 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
329 # If we have "make <whatever> modules", compile modules
330 # in addition to whatever we do anyway.
331 # Just "make" or "make all" shall build modules as well
333 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
337 ifeq ($(MAKECMDGOALS),)
341 export KBUILD_MODULES KBUILD_BUILTIN
342 export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
344 # We need some generic definitions (do not try to remake the file).
345 scripts/Kbuild.include: ;
346 include scripts/Kbuild.include
348 # Make variables (CC, etc...)
349 AS = $(CROSS_COMPILE)as
350 LD = $(CROSS_COMPILE)ld
351 LDGOLD = $(CROSS_COMPILE)ld.gold
352 CC = $(CROSS_COMPILE)gcc
354 AR = $(CROSS_COMPILE)ar
355 NM = $(CROSS_COMPILE)nm
356 STRIP = $(CROSS_COMPILE)strip
357 OBJCOPY = $(CROSS_COMPILE)objcopy
358 OBJDUMP = $(CROSS_COMPILE)objdump
360 GENKSYMS = scripts/genksyms/genksyms
361 INSTALLKERNEL := installkernel
362 DEPMOD = /sbin/depmod
367 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
368 -Wbitwise -Wno-return-void $(CF)
377 # Use USERINCLUDE when you must reference the UAPI directories only.
379 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
380 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
381 -I$(srctree)/include/uapi \
382 -I$(objtree)/include/generated/uapi \
383 -include $(srctree)/include/linux/kconfig.h
385 # Use LINUXINCLUDE when you must reference the include/ directory.
386 # Needed to be compatible with the O= option
388 -I$(srctree)/arch/$(hdr-arch)/include \
389 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
390 -I$(objtree)/arch/$(hdr-arch)/include/generated \
391 $(if $(KBUILD_SRC), -I$(srctree)/include) \
394 LINUXINCLUDE += $(filter-out $(LINUXINCLUDE),$(USERINCLUDE))
396 KBUILD_AFLAGS := -D__ASSEMBLY__
397 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
398 -fno-strict-aliasing -fno-common \
399 -Werror-implicit-function-declaration \
400 -Wno-format-security \
402 KBUILD_CPPFLAGS := -D__KERNEL__
403 KBUILD_AFLAGS_KERNEL :=
404 KBUILD_CFLAGS_KERNEL :=
405 KBUILD_AFLAGS_MODULE := -DMODULE
406 KBUILD_CFLAGS_MODULE := -DMODULE
407 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
408 GCC_PLUGINS_CFLAGS :=
410 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
411 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
412 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
414 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
415 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
416 export CPP AR NM STRIP OBJCOPY OBJDUMP
417 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
418 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
420 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
421 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_KASAN CFLAGS_UBSAN
422 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
423 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
424 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
425 export KBUILD_ARFLAGS
427 # When compiling out-of-tree modules, put MODVERDIR in the module
428 # tree rather than in the kernel tree. The kernel tree might
430 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
432 # Files to ignore in find ... statements
434 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
435 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
437 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
438 --exclude CVS --exclude .pc --exclude .hg --exclude .git
440 # ===========================================================================
441 # Rules shared between *config targets and build targets
443 # Basic helpers built in scripts/
444 PHONY += scripts_basic
446 $(Q)$(MAKE) $(build)=scripts/basic
447 $(Q)rm -f .tmp_quiet_recordmcount
449 # To avoid any implicit rule to kick in, define an empty command.
450 scripts/basic/%: scripts_basic ;
452 PHONY += outputmakefile
453 # outputmakefile generates a Makefile in the output directory, if using a
454 # separate output directory. This allows convenient use of make in the
457 ifneq ($(KBUILD_SRC),)
458 $(Q)ln -fsn $(srctree) source
459 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
460 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
463 # Support for using generic headers in asm-generic
466 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
467 src=asm obj=arch/$(SRCARCH)/include/generated/asm
468 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
469 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
471 # To make sure we do not include .config for any of the *config targets
472 # catch them early, and hand them over to scripts/kconfig/Makefile
473 # It is allowed to specify more targets when calling make, including
474 # mixing *config targets and build targets.
475 # For example 'make oldconfig all'.
476 # Detect when mixed targets is specified, and make a second invocation
477 # of make so .config is not included in this case either (for *config).
479 version_h := include/generated/uapi/linux/version.h
480 old_version_h := include/linux/version.h
482 no-dot-config-targets := clean mrproper distclean \
483 cscope gtags TAGS tags help% %docs check% coccicheck \
484 $(version_h) headers_% archheaders archscripts \
485 kernelversion %src-pkg
491 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
492 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
497 ifeq ($(KBUILD_EXTMOD),)
498 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
500 ifneq ($(words $(MAKECMDGOALS)),1)
505 # install and module_install need also be processed one by one
506 ifneq ($(filter install,$(MAKECMDGOALS)),)
507 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
512 ifeq ($(mixed-targets),1)
513 # ===========================================================================
514 # We're called with mixed targets (*config and build targets).
515 # Handle them one by one.
517 PHONY += $(MAKECMDGOALS) __build_one_by_one
519 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
524 for i in $(MAKECMDGOALS); do \
525 $(MAKE) -f $(srctree)/Makefile $$i; \
529 ifeq ($(config-targets),1)
530 # ===========================================================================
531 # *config targets only - make sure prerequisites are updated, and descend
532 # in scripts/kconfig to make the *config target
534 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
535 # KBUILD_DEFCONFIG may point out an alternative default configuration
536 # used for 'make defconfig'
537 include arch/$(SRCARCH)/Makefile
538 export KBUILD_DEFCONFIG KBUILD_KCONFIG
540 config: scripts_basic outputmakefile FORCE
541 $(Q)$(MAKE) $(build)=scripts/kconfig $@
543 %config: scripts_basic outputmakefile FORCE
544 $(Q)$(MAKE) $(build)=scripts/kconfig $@
547 # ===========================================================================
548 # Build targets only - this includes vmlinux, arch specific targets, clean
549 # targets and others. In general all targets except *config targets.
551 ifeq ($(KBUILD_EXTMOD),)
552 # Additional helpers built in scripts/
553 # Carefully list dependencies so we do not try to build scripts twice
556 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
557 asm-generic gcc-plugins
558 $(Q)$(MAKE) $(build)=$(@)
560 # Objects we will link into vmlinux / subdirs we need to visit
562 drivers-y := drivers/ sound/ firmware/
567 endif # KBUILD_EXTMOD
569 ifeq ($(dot-config),1)
571 -include include/config/auto.conf
573 ifeq ($(KBUILD_EXTMOD),)
574 # Read in dependencies to all Kconfig* files, make sure to run
575 # oldconfig if changes are detected.
576 -include include/config/auto.conf.cmd
578 # To avoid any implicit rule to kick in, define an empty command
579 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
581 # If .config is newer than include/config/auto.conf, someone tinkered
582 # with it and forgot to run make oldconfig.
583 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
584 # we execute the config step to be sure to catch updated Kconfig files
585 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
586 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
588 # external modules needs include/generated/autoconf.h and include/config/auto.conf
589 # but do not care if they are up-to-date. Use auto.conf to trigger the test
590 PHONY += include/config/auto.conf
592 include/config/auto.conf:
593 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
595 echo >&2 " ERROR: Kernel configuration is invalid."; \
596 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
597 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
601 endif # KBUILD_EXTMOD
604 # Dummy target needed, because used as prerequisite
605 include/config/auto.conf: ;
606 endif # $(dot-config)
608 # For the kernel to actually contain only the needed exported symbols,
609 # we have to build modules as well to determine what those symbols are.
610 # (this can be evaluated only once include/config/auto.conf has been included)
611 ifdef CONFIG_TRIM_UNUSED_KSYMS
615 # The all: target is the default when no target is given on the
617 # This allow a user to issue only 'make' to build a kernel including modules
618 # Defaults to vmlinux, but the arch makefile usually adds further targets
621 KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
622 KBUILD_AFLAGS += $(call cc-option,-fno-PIE)
623 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
624 CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,)
625 export CFLAGS_GCOV CFLAGS_KCOV
627 # Make toolchain changes before including arch/$(SRCARCH)/Makefile to ensure
628 # ar/cc/ld-* macros return correct values.
629 ifdef CONFIG_LTO_CLANG
630 # use GNU gold with LLVMgold for LTO linking, and LD for vmlinux_link
631 LDFINAL_vmlinux := $(LD)
633 LDFLAGS += -plugin LLVMgold.so
634 # use llvm-ar for building symbol tables from IR files, and llvm-dis instead
635 # of objdump for processing symbol versions and exports
638 export LLVM_AR LLVM_DIS
641 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
642 # values of the respective KBUILD_* variables
646 include arch/$(SRCARCH)/Makefile
648 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
649 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
650 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
651 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
652 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
654 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
655 KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,)
656 KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
659 ifdef CONFIG_LTO_CLANG
660 lto-clang-flags := -flto -fvisibility=hidden
662 # allow disabling only clang LTO where needed
663 DISABLE_LTO_CLANG := -fno-lto -fvisibility=default
664 export DISABLE_LTO_CLANG
668 lto-flags := $(lto-clang-flags)
669 KBUILD_CFLAGS += $(lto-flags)
671 DISABLE_LTO := $(DISABLE_LTO_CLANG)
674 # LDFINAL_vmlinux and LDFLAGS_FINAL_vmlinux can be set to override
675 # the linker and flags for vmlinux_link.
676 export LDFINAL_vmlinux LDFLAGS_FINAL_vmlinux
679 ifdef CONFIG_CFI_CLANG
680 cfi-clang-flags += -fsanitize=cfi
681 DISABLE_CFI_CLANG := -fno-sanitize=cfi
683 cfi-clang-flags += -fsanitize-cfi-cross-dso
684 DISABLE_CFI_CLANG += -fno-sanitize-cfi-cross-dso
686 ifdef CONFIG_CFI_PERMISSIVE
687 cfi-clang-flags += -fsanitize-recover=cfi -fno-sanitize-trap=cfi
690 # also disable CFI when LTO is disabled
691 DISABLE_LTO_CLANG += $(DISABLE_CFI_CLANG)
692 # allow disabling only clang CFI where needed
693 export DISABLE_CFI_CLANG
697 # cfi-flags are re-tested in prepare-compiler-check
698 cfi-flags := $(cfi-clang-flags)
699 KBUILD_CFLAGS += $(cfi-flags)
701 DISABLE_CFI := $(DISABLE_CFI_CLANG)
702 DISABLE_LTO += $(DISABLE_CFI)
706 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
707 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
708 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
710 ifdef CONFIG_PROFILE_ALL_BRANCHES
711 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
717 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
718 $(call cc-disable-warning,maybe-uninitialized,))
720 # Tell gcc to never replace conditional load with a non-conditional one
721 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
723 # check for 'asm goto'
724 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
725 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
726 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
729 include scripts/Makefile.gcc-plugins
731 ifdef CONFIG_READABLE_ASM
732 # Disable optimizations that make assembler listings hard to read.
733 # reorder blocks reorders the control in the function
734 # ipa clone creates specialized cloned functions
735 # partial inlining inlines only parts of functions
736 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
737 $(call cc-option,-fno-ipa-cp-clone,) \
738 $(call cc-option,-fno-partial-inlining)
741 ifneq ($(CONFIG_FRAME_WARN),0)
742 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
745 # This selects the stack protector compiler flag. Testing it is delayed
746 # until after .config has been reprocessed, in the prepare-compiler-check
748 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
749 stackp-flag := -fstack-protector
750 stackp-name := REGULAR
752 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
753 stackp-flag := -fstack-protector-strong
754 stackp-name := STRONG
756 # Force off for distro compilers that enable stack protector by default.
757 stackp-flag := $(call cc-option, -fno-stack-protector)
760 # Find arch-specific stack protector compiler sanity-checking script.
761 ifdef CONFIG_CC_STACKPROTECTOR
762 stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
763 stackp-check := $(wildcard $(stackp-path))
765 KBUILD_CFLAGS += $(stackp-flag)
767 ifeq ($(cc-name),clang)
768 ifneq ($(CROSS_COMPILE),)
769 CLANG_TRIPLE ?= $(CROSS_COMPILE)
770 CLANG_TARGET := --target=$(notdir $(CLANG_TRIPLE:%-=%))
771 GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..)
773 ifneq ($(GCC_TOOLCHAIN),)
774 CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
776 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
777 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
778 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
779 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
780 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
781 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
782 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
783 KBUILD_CFLAGS += $(call cc-disable-warning, duplicate-decl-specifier)
784 # Quiet clang warning: comparison of unsigned expression < 0 is always false
785 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
786 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
787 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
788 # See modpost pattern 2
789 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
790 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
791 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
792 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
795 # These warnings generated too much noise in a regular build.
796 # Use make W=1 to enable them (see scripts/Makefile.build)
797 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
798 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
801 ifdef CONFIG_FRAME_POINTER
802 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
804 # Some targets (ARM with Thumb2, for example), can't be built with frame
805 # pointers. For those, we don't have FUNCTION_TRACER automatically
806 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
807 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
808 # -fomit-frame-pointer with FUNCTION_TRACER.
809 ifndef CONFIG_FUNCTION_TRACER
810 KBUILD_CFLAGS += -fomit-frame-pointer
814 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
816 ifdef CONFIG_DEBUG_INFO
817 ifdef CONFIG_DEBUG_INFO_SPLIT
818 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
822 KBUILD_AFLAGS += -Wa,-gdwarf-2
824 ifdef CONFIG_DEBUG_INFO_DWARF4
825 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
828 ifdef CONFIG_DEBUG_INFO_REDUCED
829 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
830 $(call cc-option,-fno-var-tracking)
833 ifdef CONFIG_FUNCTION_TRACER
834 ifndef CC_FLAGS_FTRACE
835 CC_FLAGS_FTRACE := -pg
837 export CC_FLAGS_FTRACE
838 ifdef CONFIG_HAVE_FENTRY
839 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
841 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
842 KBUILD_AFLAGS += $(CC_USING_FENTRY)
843 ifdef CONFIG_DYNAMIC_FTRACE
844 ifdef CONFIG_HAVE_C_RECORDMCOUNT
845 BUILD_C_RECORDMCOUNT := y
846 export BUILD_C_RECORDMCOUNT
851 # We trigger additional mismatches with less inlining
852 ifdef CONFIG_DEBUG_SECTION_MISMATCH
853 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
856 # arch Makefile may override CC so keep this after arch Makefile is included
857 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
858 CHECKFLAGS += $(NOSTDINC_FLAGS)
860 # warn about C99 declaration after statement
861 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
863 # disable pointer signed / unsigned warnings in gcc 4.0
864 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
866 # disable invalid "can't wrap" optimizations for signed / pointers
867 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
869 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
870 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
872 # conserve stack if available
873 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
875 # disallow errors like 'EXPORT_GPL(foo);' with missing header
876 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
878 # require functions to have arguments in prototypes, not empty 'int foo()'
879 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
881 # Prohibit date/time macros, which would make the build non-deterministic
882 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
884 # enforce correct pointer usage
885 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
887 # use the deterministic mode of AR if available
888 KBUILD_ARFLAGS := $(call ar-option,D)
890 include scripts/Makefile.kasan
891 include scripts/Makefile.extrawarn
892 include scripts/Makefile.ubsan
894 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
896 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
897 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
898 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
900 # Use --build-id when available.
901 LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
902 $(call cc-ldoption, -Wl$(comma)--build-id,))
903 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
904 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
906 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
907 LDFLAGS_vmlinux += $(call ld-option, --gc-sections,)
910 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
911 LDFLAGS_vmlinux += $(call ld-option, -X,)
914 # Default kernel image to build when no specific target is given.
915 # KBUILD_IMAGE may be overruled on the command line or
916 # set in the environment
917 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
919 export KBUILD_IMAGE ?= vmlinux
922 # INSTALL_PATH specifies where to place the updated kernel and system map
923 # images. Default is /boot, but you can set it to other values
924 export INSTALL_PATH ?= /boot
927 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
928 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
929 # an argument if needed. Otherwise it defaults to the kernel install path
931 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
934 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
935 # relocations required by build roots. This is not defined in the
936 # makefile but the argument can be passed to make if needed.
939 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
943 # INSTALL_MOD_STRIP, if defined, will cause modules to be
944 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
945 # the default option --strip-debug will be used. Otherwise,
946 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
948 ifdef INSTALL_MOD_STRIP
949 ifeq ($(INSTALL_MOD_STRIP),1)
950 mod_strip_cmd = $(STRIP) --strip-debug
952 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
953 endif # INSTALL_MOD_STRIP=1
956 endif # INSTALL_MOD_STRIP
959 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
960 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
961 # or CONFIG_MODULE_COMPRESS_XZ.
963 mod_compress_cmd = true
964 ifdef CONFIG_MODULE_COMPRESS
965 ifdef CONFIG_MODULE_COMPRESS_GZIP
966 mod_compress_cmd = gzip -n -f
967 endif # CONFIG_MODULE_COMPRESS_GZIP
968 ifdef CONFIG_MODULE_COMPRESS_XZ
969 mod_compress_cmd = xz -f
970 endif # CONFIG_MODULE_COMPRESS_XZ
971 endif # CONFIG_MODULE_COMPRESS
972 export mod_compress_cmd
974 # Select initial ramdisk compression format, default is gzip(1).
975 # This shall be used by the dracut(8) tool while creating an initramfs image.
977 INITRD_COMPRESS-y := gzip
978 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
979 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
980 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
981 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
982 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
983 # do not export INITRD_COMPRESS, since we didn't actually
984 # choose a sane default compression above.
985 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
987 ifdef CONFIG_MODULE_SIG_ALL
988 $(eval $(call config_filename,MODULE_SIG_KEY))
990 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
997 ifeq ($(KBUILD_EXTMOD),)
998 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1000 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1001 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1002 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1004 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
1005 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
1007 init-y := $(patsubst %/, %/built-in.o, $(init-y))
1008 core-y := $(patsubst %/, %/built-in.o, $(core-y))
1009 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
1010 net-y := $(patsubst %/, %/built-in.o, $(net-y))
1011 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
1012 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
1013 libs-y := $(libs-y1) $(libs-y2)
1014 virt-y := $(patsubst %/, %/built-in.o, $(virt-y))
1016 # Externally visible symbols (used by link-vmlinux.sh)
1017 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
1018 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y)
1019 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1020 export LDFLAGS_vmlinux
1021 # used by scripts/pacmage/Makefile
1022 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
1024 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
1026 # Include targets which we want to execute sequentially if the rest of the
1027 # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
1028 # evaluated more than once.
1029 PHONY += vmlinux_prereq
1030 vmlinux_prereq: $(vmlinux-deps) FORCE
1031 ifdef CONFIG_HEADERS_CHECK
1032 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
1034 ifdef CONFIG_GDB_SCRIPTS
1035 $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
1037 ifdef CONFIG_TRIM_UNUSED_KSYMS
1038 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1039 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1042 # standalone target for easier testing
1043 include/generated/autoksyms.h: FORCE
1044 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
1046 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1048 # Final link of vmlinux with optional arch pass after final link
1049 cmd_link-vmlinux = \
1050 $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
1051 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1053 vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
1054 +$(call if_changed,link-vmlinux)
1056 # Build samples along the rest of the kernel
1057 ifdef CONFIG_SAMPLES
1058 vmlinux-dirs += samples
1061 # The actual objects are generated when descending,
1062 # make sure no implicit rule kicks in
1063 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1065 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1066 # Preset locale variables to speed up the build process. Limit locale
1067 # tweaks to this spot to avoid wrong language settings when running
1068 # make menuconfig etc.
1069 # Error messages still appears in the original language
1071 PHONY += $(vmlinux-dirs)
1072 $(vmlinux-dirs): prepare scripts
1073 $(Q)$(MAKE) $(build)=$@
1075 define filechk_kernel.release
1076 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1079 # Store (new) KERNELRELEASE string in include/config/kernel.release
1080 include/config/kernel.release: include/config/auto.conf FORCE
1081 $(call filechk,kernel.release)
1084 # Things we need to do before we recursively start building the kernel
1085 # or the modules are listed in "prepare".
1086 # A multi level approach is used. prepareN is processed before prepareN-1.
1087 # archprepare is used in arch Makefiles and when processed asm symlink,
1088 # version.h and scripts_basic is processed / created.
1090 # Listed in dependency order
1091 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1093 # prepare3 is used to check if we are building in a separate output directory,
1095 # 1) Check that make has not been executed in the kernel src $(srctree)
1096 prepare3: include/config/kernel.release
1097 ifneq ($(KBUILD_SRC),)
1098 @$(kecho) ' Using $(srctree) as source for kernel'
1099 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1100 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1101 echo >&2 " in the '$(srctree)' directory.";\
1106 # prepare2 creates a makefile if using a separate output directory.
1107 # From this point forward, .config has been reprocessed, so any rules
1108 # that need to depend on updated CONFIG_* values can be checked here.
1109 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
1111 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
1112 include/config/auto.conf
1115 archprepare: archheaders archscripts prepare1 scripts_basic
1117 prepare0: archprepare gcc-plugins
1118 $(Q)$(MAKE) $(build)=.
1120 # All the preparing..
1121 prepare: prepare0 prepare-objtool
1123 ifdef CONFIG_STACK_VALIDATION
1124 has_libelf := $(call try-run,\
1125 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
1126 ifeq ($(has_libelf),1)
1127 objtool_target := tools/objtool FORCE
1129 $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
1130 SKIP_STACK_VALIDATION := 1
1131 export SKIP_STACK_VALIDATION
1135 PHONY += prepare-objtool
1136 prepare-objtool: $(objtool_target)
1138 # Check for CONFIG flags that require compiler support. Abort the build
1139 # after .config has been processed, but before the kernel build starts.
1141 # For security-sensitive CONFIG options, we don't want to fallback and/or
1142 # silently change which compiler flags will be used, since that leads to
1143 # producing kernels with different security feature characteristics
1144 # depending on the compiler used. (For example, "But I selected
1145 # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
1146 PHONY += prepare-compiler-check
1147 prepare-compiler-check: FORCE
1148 # Make sure we're using a supported toolchain with LTO_CLANG
1149 ifdef CONFIG_LTO_CLANG
1150 ifneq ($(call clang-ifversion, -ge, 0500, y), y)
1151 @echo Cannot use CONFIG_LTO_CLANG: requires clang 5.0 or later >&2 && exit 1
1153 ifneq ($(call gold-ifversion, -ge, 112000000, y), y)
1154 @echo Cannot use CONFIG_LTO_CLANG: requires GNU gold 1.12 or later >&2 && exit 1
1157 # Make sure compiler supports LTO flags
1159 ifeq ($(call cc-option, $(lto-flags)),)
1160 @echo Cannot use CONFIG_LTO: $(lto-flags) not supported by compiler \
1164 # Make sure compiler supports requested stack protector flag.
1166 ifeq ($(call cc-option, $(stackp-flag)),)
1167 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1168 $(stackp-flag) not supported by compiler >&2 && exit 1
1171 # Make sure compiler does not have buggy stack-protector support.
1173 ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
1174 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1175 $(stackp-flag) available but compiler is broken >&2 && exit 1
1179 ifeq ($(call cc-option, $(cfi-flags)),)
1180 @echo Cannot use CONFIG_CFI: $(cfi-flags) not supported by compiler >&2 && exit 1
1185 # Generate some files
1186 # ---------------------------------------------------------------------------
1188 # KERNELRELEASE can change from a few different places, meaning version.h
1189 # needs to be updated, so this check is forced on all builds
1192 define filechk_utsrelease.h
1193 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1194 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1197 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1200 define filechk_version.h
1201 (echo \#define LINUX_VERSION_CODE $(shell \
1202 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1203 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1206 $(version_h): $(srctree)/Makefile FORCE
1207 $(call filechk,version.h)
1208 $(Q)rm -f $(old_version_h)
1210 include/generated/utsrelease.h: include/config/kernel.release FORCE
1211 $(call filechk,utsrelease.h)
1215 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1216 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1218 # ---------------------------------------------------------------------------
1220 INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1221 export INSTALL_FW_PATH
1223 PHONY += firmware_install
1225 @mkdir -p $(objtree)/firmware
1226 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1228 # ---------------------------------------------------------------------------
1231 #Default location for installed headers
1232 export INSTALL_HDR_PATH = $(objtree)/usr
1234 # If we do an all arch process set dst to asm-$(hdr-arch)
1235 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
1237 PHONY += archheaders
1240 PHONY += archscripts
1244 __headers: $(version_h) scripts_basic asm-generic archheaders archscripts
1245 $(Q)$(MAKE) $(build)=scripts build_unifdef
1247 PHONY += headers_install_all
1248 headers_install_all:
1249 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1251 PHONY += headers_install
1252 headers_install: __headers
1253 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1254 $(error Headers not exportable for the $(SRCARCH) architecture))
1255 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1256 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
1258 PHONY += headers_check_all
1259 headers_check_all: headers_install_all
1260 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1262 PHONY += headers_check
1263 headers_check: headers_install
1264 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1265 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
1267 # ---------------------------------------------------------------------------
1272 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1275 $(Q)$(MAKE) -C tools/testing/selftests clean
1277 PHONY += kselftest-merge
1279 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1280 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1281 -m $(objtree)/.config \
1282 $(srctree)/tools/testing/selftests/*/config
1283 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1285 # ---------------------------------------------------------------------------
1288 ifdef CONFIG_MODULES
1290 # By default, build modules as well
1296 # A module can be listed more than once in obj-m resulting in
1297 # duplicate lines in modules.order files. Those are removed
1298 # using awk while concatenating to the final file.
1301 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1302 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1303 @$(kecho) ' Building modules, stage 2.';
1304 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1305 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1307 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1308 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1310 %/modules.builtin: include/config/auto.conf
1311 $(Q)$(MAKE) $(modbuiltin)=$*
1314 # Target to prepare building external modules
1315 PHONY += modules_prepare
1316 modules_prepare: prepare scripts
1318 # Target to install modules
1319 PHONY += modules_install
1320 modules_install: _modinst_ _modinst_post
1324 @rm -rf $(MODLIB)/kernel
1325 @rm -f $(MODLIB)/source
1326 @mkdir -p $(MODLIB)/kernel
1327 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1328 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1329 rm -f $(MODLIB)/build ; \
1330 ln -s $(CURDIR) $(MODLIB)/build ; \
1332 @cp -f $(objtree)/modules.order $(MODLIB)/
1333 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1334 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1336 # This depmod is only for convenience to give the initial
1337 # boot a modules.dep even before / is mounted read-write. However the
1338 # boot script depmod is the master version.
1339 PHONY += _modinst_post
1340 _modinst_post: _modinst_
1341 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1344 ifeq ($(CONFIG_MODULE_SIG), y)
1345 PHONY += modules_sign
1347 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1350 else # CONFIG_MODULES
1352 # Modules not configured
1353 # ---------------------------------------------------------------------------
1355 PHONY += modules modules_install
1356 modules modules_install:
1358 @echo >&2 "The present kernel configuration has modules disabled."
1359 @echo >&2 "Type 'make config' and enable loadable module support."
1360 @echo >&2 "Then build a kernel with module support enabled."
1364 endif # CONFIG_MODULES
1367 # Cleaning is done on three levels.
1368 # make clean Delete most generated files
1369 # Leave enough to build external modules
1370 # make mrproper Delete the current configuration, and all generated files
1371 # make distclean Remove editor backup files, patch leftover files and the like
1373 # Directories & files removed with 'make clean'
1374 CLEAN_DIRS += $(MODVERDIR)
1376 # Directories & files removed with 'make mrproper'
1377 MRPROPER_DIRS += include/config usr/include include/generated \
1378 arch/*/include/generated .tmp_objdiff
1379 MRPROPER_FILES += .config .config.old .version .old_version \
1380 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1381 signing_key.pem signing_key.priv signing_key.x509 \
1382 x509.genkey extra_certificates signing_key.x509.keyid \
1383 signing_key.x509.signer vmlinux-gdb.py
1385 # clean - Delete most, but leave enough to build external modules
1387 clean: rm-dirs := $(CLEAN_DIRS)
1388 clean: rm-files := $(CLEAN_FILES)
1389 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1391 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1393 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1396 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1397 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1399 clean: archclean vmlinuxclean
1401 # mrproper - Delete all generated files, including .config
1403 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1404 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1405 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1407 PHONY += $(mrproper-dirs) mrproper archmrproper
1409 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1411 mrproper: clean archmrproper $(mrproper-dirs)
1420 @find $(srctree) $(RCS_FIND_IGNORE) \
1421 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1422 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1423 -o -name '.*.rej' -o -name '*%' -o -name 'core' \) \
1424 -type f -print | xargs rm -f
1427 # Packaging of the kernel to various formats
1428 # ---------------------------------------------------------------------------
1429 # rpm target kept for backward compatibility
1430 package-dir := scripts/package
1433 $(Q)$(MAKE) $(build)=$(package-dir) $@
1434 %pkg: include/config/kernel.release FORCE
1435 $(Q)$(MAKE) $(build)=$(package-dir) $@
1436 rpm: include/config/kernel.release FORCE
1437 $(Q)$(MAKE) $(build)=$(package-dir) $@
1440 # Brief documentation of the typical targets used
1441 # ---------------------------------------------------------------------------
1443 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1444 boards := $(sort $(notdir $(boards)))
1445 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1446 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1450 @echo 'Cleaning targets:'
1451 @echo ' clean - Remove most generated files but keep the config and'
1452 @echo ' enough build support to build external modules'
1453 @echo ' mrproper - Remove all generated files + config + various backup files'
1454 @echo ' distclean - mrproper + remove editor backup and patch files'
1456 @echo 'Configuration targets:'
1457 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1459 @echo 'Other generic targets:'
1460 @echo ' all - Build all targets marked with [*]'
1461 @echo '* vmlinux - Build the bare kernel'
1462 @echo '* modules - Build all modules'
1463 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1464 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1465 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1466 @echo ' dir/ - Build all files in dir and below'
1467 @echo ' dir/file.[ois] - Build specified target only'
1468 @echo ' dir/file.ll - Build the LLVM assembly file'
1469 @echo ' (requires compiler support for LLVM assembly generation)'
1470 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1471 @echo ' (requires a recent binutils and recent build (System.map))'
1472 @echo ' dir/file.ko - Build module including final link'
1473 @echo ' modules_prepare - Set up for building external modules'
1474 @echo ' tags/TAGS - Generate tags file for editors'
1475 @echo ' cscope - Generate cscope index'
1476 @echo ' gtags - Generate GNU GLOBAL index'
1477 @echo ' kernelrelease - Output the release version string (use with make -s)'
1478 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1479 @echo ' image_name - Output the image name (use with make -s)'
1480 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1481 echo ' (default: $(INSTALL_HDR_PATH))'; \
1483 @echo 'Static analysers'
1484 @echo ' checkstack - Generate a list of stack hogs'
1485 @echo ' namespacecheck - Name space analysis on compiled kernel'
1486 @echo ' versioncheck - Sanity check on version.h usage'
1487 @echo ' includecheck - Check for duplicate included header files'
1488 @echo ' export_report - List the usages of all exported symbols'
1489 @echo ' headers_check - Sanity check on exported headers'
1490 @echo ' headerdep - Detect inclusion cycles in headers'
1491 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1493 @echo 'Kernel selftest'
1494 @echo ' kselftest - Build and run kernel selftest (run as root)'
1495 @echo ' Build, install, and boot kernel before'
1496 @echo ' running kselftest on it'
1497 @echo ' kselftest-clean - Remove all generated kselftest files'
1498 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existed'
1501 @echo 'Kernel packaging:'
1502 @$(MAKE) $(build)=$(package-dir) help
1504 @echo 'Documentation targets:'
1505 @$(MAKE) -f $(srctree)/Documentation/Makefile.sphinx dochelp
1507 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1509 @echo 'Architecture specific targets ($(SRCARCH)):'
1510 @$(if $(archhelp),$(archhelp),\
1511 echo ' No architecture specific help defined for $(SRCARCH)')
1514 $(foreach b, $(boards), \
1515 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1517 @$(if $(board-dirs), \
1518 $(foreach b, $(board-dirs), \
1519 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1520 printf " %-16s - Show all of the above\\n" help-boards; \
1523 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1524 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1525 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1526 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1527 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1528 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1529 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1530 @echo ' 1: warnings which may be relevant and do not occur too often'
1531 @echo ' 2: warnings which occur quite often but may still be relevant'
1532 @echo ' 3: more obscure warnings, can most likely be ignored'
1533 @echo ' Multiple levels can be combined with W=12 or W=123'
1535 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1536 @echo 'For further info see the ./README file'
1539 help-board-dirs := $(addprefix help-,$(board-dirs))
1541 help-boards: $(help-board-dirs)
1543 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1545 $(help-board-dirs): help-%:
1546 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1547 @$(if $(boards-per-dir), \
1548 $(foreach b, $(boards-per-dir), \
1549 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1553 # Documentation targets
1554 # ---------------------------------------------------------------------------
1555 DOC_TARGETS := xmldocs sgmldocs psdocs latexdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs
1556 PHONY += $(DOC_TARGETS)
1557 $(DOC_TARGETS): scripts_basic FORCE
1558 $(Q)$(MAKE) $(build)=scripts build_docproc build_check-lc_ctype
1559 $(Q)$(MAKE) $(build)=Documentation -f $(srctree)/Documentation/Makefile.sphinx $@
1560 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1562 else # KBUILD_EXTMOD
1565 # External module support.
1566 # When building external modules the kernel used as basis is considered
1567 # read-only, and no consistency checks are made and the make
1568 # system is not used on the basis kernel. If updates are required
1569 # in the basis kernel ordinary make commands (without M=...) must
1572 # The following are the only valid targets when building external
1574 # make M=dir clean Delete all automatically generated files
1575 # make M=dir modules Make all modules in specified dir
1576 # make M=dir Same as 'make M=dir modules'
1577 # make M=dir modules_install
1578 # Install the modules built in the module directory
1579 # Assumes install directory is already created
1581 # We are always building modules
1583 PHONY += crmodverdir
1587 PHONY += $(objtree)/Module.symvers
1588 $(objtree)/Module.symvers:
1589 @test -e $(objtree)/Module.symvers || ( \
1591 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1592 echo " is missing; modules will have no dependencies and modversions."; \
1595 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1596 PHONY += $(module-dirs) modules
1597 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1598 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1600 modules: $(module-dirs)
1601 @$(kecho) ' Building modules, stage 2.';
1602 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1604 PHONY += modules_install
1605 modules_install: _emodinst_ _emodinst_post
1607 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1610 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1611 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1613 PHONY += _emodinst_post
1614 _emodinst_post: _emodinst_
1617 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1619 PHONY += $(clean-dirs) clean
1621 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1623 clean: rm-dirs := $(MODVERDIR)
1624 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1628 @echo ' Building external modules.'
1629 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1631 @echo ' modules - default target, build the module(s)'
1632 @echo ' modules_install - install the module'
1633 @echo ' clean - remove generated files in module directory only'
1637 PHONY += prepare scripts
1640 endif # KBUILD_EXTMOD
1642 clean: $(clean-dirs)
1645 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1646 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1650 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1651 -o -name '*.symtypes' -o -name 'modules.order' \
1652 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1653 -o -name '*.c.[012]*.*' \
1656 -o -name '*.*.symversions' \) -type f -print | xargs rm -f
1658 # Generate tags for editors
1659 # ---------------------------------------------------------------------------
1660 quiet_cmd_tags = GEN $@
1661 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1663 tags TAGS cscope gtags: FORCE
1666 # Scripts to check various things for consistency
1667 # ---------------------------------------------------------------------------
1669 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1672 find $(srctree)/* $(RCS_FIND_IGNORE) \
1673 -name '*.[hcS]' -type f -print | sort \
1674 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1677 find $(srctree)/* $(RCS_FIND_IGNORE) \
1678 -name '*.[hcS]' -type f -print | sort \
1679 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1682 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1685 $(PERL) $(srctree)/scripts/namespace.pl
1688 $(PERL) $(srctree)/scripts/export_report.pl
1690 endif #ifeq ($(config-targets),1)
1691 endif #ifeq ($(mixed-targets),1)
1693 PHONY += checkstack kernelrelease kernelversion image_name
1695 # UML needs a little special treatment here. It wants to use the host
1696 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1697 # else wants $(ARCH), including people doing cross-builds, which means
1698 # that $(SUBARCH) doesn't work here.
1700 CHECKSTACK_ARCH := $(SUBARCH)
1702 CHECKSTACK_ARCH := $(ARCH)
1705 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1706 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1709 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1712 @echo $(KERNELVERSION)
1715 @echo $(KBUILD_IMAGE)
1717 # Clear a bunch of variables before executing the submake
1719 $(Q)mkdir -p $(objtree)/tools
1720 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
1723 $(Q)mkdir -p $(objtree)/tools
1724 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
1727 # ---------------------------------------------------------------------------
1728 # Single targets are compatible with:
1729 # - build with mixed source and output
1730 # - build with separate output dir 'make O=...'
1731 # - external modules
1733 # target-dir => where to store outputfile
1734 # build-dir => directory in kernel source tree to use
1736 ifeq ($(KBUILD_EXTMOD),)
1737 build-dir = $(patsubst %/,%,$(dir $@))
1738 target-dir = $(dir $@)
1740 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1741 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1742 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1745 %.s: %.c prepare scripts FORCE
1746 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1747 %.i: %.c prepare scripts FORCE
1748 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1749 %.o: %.c prepare scripts FORCE
1750 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1751 %.lst: %.c prepare scripts FORCE
1752 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1753 %.s: %.S prepare scripts FORCE
1754 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1755 %.o: %.S prepare scripts FORCE
1756 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1757 %.symtypes: %.c prepare scripts FORCE
1758 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1759 %.ll: %.c prepare scripts FORCE
1760 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1763 /: prepare scripts FORCE
1765 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1766 $(build)=$(build-dir)
1767 # Make sure the latest headers are built for Documentation
1768 Documentation/ samples/: headers_install
1769 %/: prepare scripts FORCE
1771 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1772 $(build)=$(build-dir)
1773 %.ko: prepare scripts FORCE
1775 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1776 $(build)=$(build-dir) $(@:.ko=.o)
1777 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1779 # FIXME Should go into a make.lib or something
1780 # ===========================================================================
1782 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1783 cmd_rmdirs = rm -rf $(rm-dirs)
1785 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1786 cmd_rmfiles = rm -f $(rm-files)
1788 # Run depmod only if we have System.map and depmod is executable
1789 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1790 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1791 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1793 # Create temporary dir for module support files
1794 # clean it up only when building all modules
1795 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1796 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1798 # read all saved command lines
1800 targets := $(wildcard $(sort $(targets)))
1801 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1803 ifneq ($(cmd_files),)
1804 $(cmd_files): ; # Do not try to update included dependency files
1805 include $(cmd_files)
1808 endif # skip-makefile
1813 # Declare the contents of the .PHONY variable as phony. We keep that
1814 # information in a variable so we can use it in if_changed and friends.