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 # Do not print "Entering directory ..."
14 MAKEFLAGS += --no-print-directory
16 # We are using a recursive build, so we need to do a little thinking
17 # to get the ordering right.
19 # Most importantly: sub-Makefiles should only ever modify files in
20 # their own directory. If in some directory we have a dependency on
21 # a file in another dir (which doesn't happen often, but it's often
22 # unavoidable when linking the built-in.o targets which finally
23 # turn into vmlinux), we will call a sub make in that other dir, and
24 # after that we are sure that everything which is in that other dir
27 # The only cases where we need to modify files which have global
28 # effects are thus separated out and done before the recursive
29 # descending is started. They are now explicitly listed as the
32 # To put more focus on warnings, be less verbose as default
33 # Use 'make V=1' to see the full commands
36 ifeq ("$(origin V)", "command line")
44 # Call sparse as part of compilation of C files
45 # Use 'make C=1' to enable sparse checking
48 ifeq ("$(origin C)", "command line")
49 KBUILD_CHECKSRC = $(C)
52 ifndef KBUILD_CHECKSRC
56 # Use make M=dir to specify directory of external module to build
57 # Old syntax make ... SUBDIRS=$PWD is still supported
58 # Setting the environment variable KBUILD_EXTMOD take precedence
60 KBUILD_EXTMOD ?= $(SUBDIRS)
63 ifeq ("$(origin M)", "command line")
69 # kbuild supports saving output files in a separate directory.
70 # To locate output files in a separate directory two syntaxes are supported.
71 # In both cases the working directory must be the root of the kernel src.
73 # Use "make O=dir/to/store/output/files/"
75 # 2) Set KBUILD_OUTPUT
76 # Set the environment variable KBUILD_OUTPUT to point to the directory
77 # where the output files shall be placed.
78 # export KBUILD_OUTPUT=dir/to/store/output/files/
81 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
85 # KBUILD_SRC is set on invocation of make in OBJ directory
86 # KBUILD_SRC is not intended to be used by the regular user (for now)
89 # OK, Make called in directory where kernel src resides
90 # Do we want to locate output files in a separate directory?
92 ifeq ("$(origin O)", "command line")
97 # That's our default target when none is given on the command line
101 ifneq ($(KBUILD_OUTPUT),)
102 # Invoke a second make in the output directory, passing relevant variables
103 # check that the output directory actually exists
104 saved-output := $(KBUILD_OUTPUT)
105 KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
106 $(if $(KBUILD_OUTPUT),, \
107 $(error output directory "$(saved-output)" does not exist))
109 .PHONY: $(MAKECMDGOALS)
111 $(filter-out _all,$(MAKECMDGOALS)) _all:
112 $(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
113 KBUILD_SRC=$(CURDIR) KBUILD_VERBOSE=$(KBUILD_VERBOSE) \
114 KBUILD_CHECK=$(KBUILD_CHECK) KBUILD_EXTMOD="$(KBUILD_EXTMOD)" \
115 -f $(CURDIR)/Makefile $@
117 # Leave processing to above invocation of make
119 endif # ifneq ($(KBUILD_OUTPUT),)
120 endif # ifeq ($(KBUILD_SRC),)
122 # We process the rest of the Makefile if this is the final invocation of make
123 ifeq ($(skip-makefile),)
125 # If building an external module we do not care about the all: rule
126 # but instead _all depend on modules
128 ifeq ($(KBUILD_EXTMOD),)
134 srctree := $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
136 # FIXME - TOPDIR is obsolete, use srctree/objtree
143 export srctree objtree VPATH TOPDIR
146 space := $(nullstring) # end of line
148 # Take the contents of any files called localversion* and the config
149 # variable CONFIG_LOCALVERSION and append them to KERNELRELEASE. Be
150 # careful not to include files twice if building in the source
151 # directory. LOCALVERSION from the command line override all of this
153 localver := $(objtree)/localversion* $(srctree)/localversion*
154 localver := $(sort $(wildcard $(localver)))
155 # skip backup files (containing '~')
156 localver := $(foreach f, $(localver), $(if $(findstring ~, $(f)),,$(f)))
158 LOCALVERSION = $(subst $(space),, \
159 $(shell cat /dev/null $(localver)) \
160 $(patsubst "%",%,$(CONFIG_LOCALVERSION)))
162 KERNELRELEASE=$(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)$(LOCALVERSION)
164 # SUBARCH tells the usermode build what the underlying arch is. That is set
165 # first, and if a usermode build is happening, the "ARCH=um" on the command
166 # line overrides the setting of ARCH below. If a native build is happening,
167 # then ARCH is assigned, getting whatever value it gets normally, and
168 # SUBARCH is subsequently ignored.
170 SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
171 -e s/arm.*/arm/ -e s/sa110/arm/ \
172 -e s/s390x/s390/ -e s/parisc64/parisc/ )
174 # Cross compiling and selecting different set of gcc/bin-utils
175 # ---------------------------------------------------------------------------
177 # When performing cross compilation for other architectures ARCH shall be set
178 # to the target architecture. (See arch/* for the possibilities).
179 # ARCH can be set during invocation of make:
181 # Another way is to have ARCH set in the environment.
182 # The default ARCH is the host where make is executed.
184 # CROSS_COMPILE specify the prefix used for all executables used
185 # during compilation. Only gcc and related bin-utils executables
186 # are prefixed with $(CROSS_COMPILE).
187 # CROSS_COMPILE can be set on the command line
188 # make CROSS_COMPILE=ia64-linux-
189 # Alternatively CROSS_COMPILE can be set in the environment.
190 # Default value for CROSS_COMPILE is not to prefix executables
191 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
196 # Architecture as present in compile.h
197 UTS_MACHINE := $(ARCH)
199 # SHELL used by kbuild
200 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
201 else if [ -x /bin/bash ]; then echo /bin/bash; \
202 else echo sh; fi ; fi)
206 HOSTCFLAGS = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer
209 # Decide whether to build built-in, modular, or both.
210 # Normally, just do built-in.
215 # If we have only "make modules", don't compile built-in objects.
216 # When we're building modules with modversions, we need to consider
217 # the built-in objects during the descend as well, in order to
218 # make sure the checksums are uptodate before we record them.
220 ifeq ($(MAKECMDGOALS),modules)
221 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
224 # If we have "make <whatever> modules", compile modules
225 # in addition to whatever we do anyway.
226 # Just "make" or "make all" shall build modules as well
228 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
232 ifeq ($(MAKECMDGOALS),)
236 export KBUILD_MODULES KBUILD_BUILTIN KBUILD_VERBOSE
237 export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
240 # ---------------------------------------------------------------------------
242 # Normally, we echo the whole command before executing it. By making
243 # that echo $($(quiet)$(cmd)), we now have the possibility to set
244 # $(quiet) to choose other forms of output instead, e.g.
246 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
247 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
249 # If $(quiet) is empty, the whole command will be printed.
250 # If it is set to "quiet_", only the short version will be printed.
251 # If it is set to "silent_", nothing wil be printed at all, since
252 # the variable $(silent_cmd_cc_o_c) doesn't exist.
254 # A simple variant is to prefix commands with $(Q) - that's usefull
255 # for commands that shall be hidden in non-verbose mode.
259 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
260 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
262 ifeq ($(KBUILD_VERBOSE),1)
270 # If the user is running make -s (silent mode), suppress echoing of
273 ifneq ($(findstring s,$(MAKEFLAGS)),)
277 export quiet Q KBUILD_VERBOSE
280 # cc support functions to be used (only) in arch/$(ARCH)/Makefile
281 # See documentation in Documentation/kbuild/makefiles.txt
284 # Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
286 cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
287 > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
289 # For backward compatibility
290 check_gcc = $(warning check_gcc is deprecated - use cc-option) \
291 $(call cc-option, $(1),$(2))
294 # Usage: flag := $(call cc-option-yn, -march=winchip-c6)
295 cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
296 > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
299 # Prefix align with either -falign or -malign
300 cc-option-align = $(subst -functions=0,,\
301 $(call cc-option,-falign-functions=0,-malign-functions=0))
304 # Usage gcc-ver := $(call cc-version $(CC))
305 cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh \
306 $(if $(1), $(1), $(CC)))
309 # Look for make include files relative to root of kernel src
310 MAKEFLAGS += --include-dir=$(srctree)
312 # For maximum performance (+ possibly random breakage, uncomment
317 # Make variables (CC, etc...)
319 AS = $(CROSS_COMPILE)as
320 LD = $(CROSS_COMPILE)ld
321 CC = $(CROSS_COMPILE)gcc
323 AR = $(CROSS_COMPILE)ar
324 NM = $(CROSS_COMPILE)nm
325 STRIP = $(CROSS_COMPILE)strip
326 OBJCOPY = $(CROSS_COMPILE)objcopy
327 OBJDUMP = $(CROSS_COMPILE)objdump
329 GENKSYMS = scripts/genksyms/genksyms
330 DEPMOD = /sbin/depmod
331 KALLSYMS = scripts/kallsyms
335 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__
337 CFLAGS_MODULE = $(MODFLAGS)
338 AFLAGS_MODULE = $(MODFLAGS)
344 # Use LINUXINCLUDE when you must reference the include/ directory.
345 # Needed to be compatible with the O= option
346 LINUXINCLUDE := -Iinclude \
347 $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include)
349 CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE)
351 CFLAGS := -Wall -Wstrict-prototypes -Wno-trigraphs \
352 -fno-strict-aliasing -fno-common \
354 AFLAGS := -D__ASSEMBLY__
356 export VERSION PATCHLEVEL SUBLEVEL EXTRAVERSION LOCALVERSION KERNELRELEASE \
357 ARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC \
358 CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE \
359 HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
361 export CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
362 export CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
363 export AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
365 # When compiling out-of-tree modules, put MODVERDIR in the module
366 # tree rather than in the kernel tree. The kernel tree might
368 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
370 # The temporary file to save gcc -MD generated dependencies must not
373 depfile = $(subst $(comma),_,$(@D)/.$(@F).d)
375 # Files to ignore in find ... statements
377 RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS -o -name .pc \) -prune -o
378 RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn --exclude CVS --exclude .pc
380 # ===========================================================================
381 # Rules shared between *config targets and build targets
383 # Basic helpers built in scripts/
384 .PHONY: scripts_basic
386 $(Q)$(MAKE) $(build)=scripts/basic
388 .PHONY: outputmakefile
389 # outputmakefile generate a Makefile to be placed in output directory, if
390 # using a seperate output directory. This allows convinient use
391 # of make in output directory
393 $(Q)if test ! $(srctree) -ef $(objtree); then \
394 $(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
395 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL) \
396 > $(objtree)/Makefile; \
397 echo ' GEN $(objtree)/Makefile'; \
400 # To make sure we do not include .config for any of the *config targets
401 # catch them early, and hand them over to scripts/kconfig/Makefile
402 # It is allowed to specify more targets when calling make, including
403 # mixing *config targets and build targets.
404 # For example 'make oldconfig all'.
405 # Detect when mixed targets is specified, and make a second invocation
406 # of make so .config is not included in this case either (for *config).
408 no-dot-config-targets := clean mrproper distclean \
409 cscope TAGS tags help %docs check%
415 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
416 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
421 ifeq ($(KBUILD_EXTMOD),)
422 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
424 ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
430 ifeq ($(mixed-targets),1)
431 # ===========================================================================
432 # We're called with mixed targets (*config and build targets).
433 # Handle them one by one.
436 $(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@
439 ifeq ($(config-targets),1)
440 # ===========================================================================
441 # *config targets only - make sure prerequisites are updated, and descend
442 # in scripts/kconfig to make the *config target
444 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
445 # KBUILD_DEFCONFIG may point out an alternative default configuration
446 # used for 'make defconfig'
447 include $(srctree)/arch/$(ARCH)/Makefile
448 export KBUILD_DEFCONFIG
450 config: scripts_basic outputmakefile FORCE
451 $(Q)$(MAKE) $(build)=scripts/kconfig $@
452 %config: scripts_basic outputmakefile FORCE
453 $(Q)$(MAKE) $(build)=scripts/kconfig $@
456 # ===========================================================================
457 # Build targets only - this includes vmlinux, arch specific targets, clean
458 # targets and others. In general all targets except *config targets.
460 ifeq ($(KBUILD_EXTMOD),)
461 # Additional helpers built in scripts/
462 # Carefully list dependencies so we do not try to build scripts twice
465 scripts: scripts_basic include/config/MARKER
466 $(Q)$(MAKE) $(build)=$(@)
468 scripts_basic: include/linux/autoconf.h
470 # Objects we will link into vmlinux / subdirs we need to visit
472 drivers-y := drivers/ sound/
476 endif # KBUILD_EXTMOD
478 ifeq ($(dot-config),1)
479 # In this section, we need .config
481 # Read in dependencies to all Kconfig* files, make sure to run
482 # oldconfig if changes are detected.
487 # If .config needs to be updated, it will be done via the dependency
488 # that autoconf has on .config.
489 # To avoid any implicit rule to kick in, define an empty command
492 # If .config is newer than include/linux/autoconf.h, someone tinkered
493 # with it and forgot to run make oldconfig
494 include/linux/autoconf.h: .config
495 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
497 # Dummy target needed, because used as prerequisite
498 include/linux/autoconf.h: ;
501 # The all: target is the default when no target is given on the
503 # This allow a user to issue only 'make' to build a kernel including modules
504 # Defaults vmlinux but it is usually overriden in the arch makefile
507 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
513 #Add align options if CONFIG_CC_* is not equal to 0
514 add-align = $(if $(filter-out 0,$($(1))),$(cc-option-align)$(2)=$($(1)))
515 CFLAGS += $(call add-align,CONFIG_CC_ALIGN_FUNCTIONS,-functions)
516 CFLAGS += $(call add-align,CONFIG_CC_ALIGN_LABELS,-labels)
517 CFLAGS += $(call add-align,CONFIG_CC_ALIGN_LOOPS,-loops)
518 CFLAGS += $(call add-align,CONFIG_CC_ALIGN_JUMPS,-jumps)
520 ifdef CONFIG_FRAME_POINTER
521 CFLAGS += -fno-omit-frame-pointer $(call cc-option,-fno-optimize-sibling-calls,)
523 CFLAGS += -fomit-frame-pointer
526 ifdef CONFIG_DEBUG_INFO
530 include $(srctree)/arch/$(ARCH)/Makefile
532 # arch Makefile may override CC so keep this after arch Makefile is included
533 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
534 CHECKFLAGS += $(NOSTDINC_FLAGS)
536 # warn about C99 declaration after statement
537 CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
539 # disable pointer signedness warnings in gcc 4.0
540 CFLAGS += $(call cc-option,-Wno-pointer-sign,)
542 # Default kernel image to build when no specific target is given.
543 # KBUILD_IMAGE may be overruled on the commandline or
544 # set in the environment
545 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
547 export KBUILD_IMAGE ?= vmlinux
550 # INSTALL_PATH specifies where to place the updated kernel and system map
551 # images. Default is /boot, but you can set it to other values
552 export INSTALL_PATH ?= /boot
555 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
556 # relocations required by build roots. This is not defined in the
557 # makefile but the arguement can be passed to make if needed.
560 MODLIB := $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
564 ifeq ($(KBUILD_EXTMOD),)
565 core-y += kernel/ mm/ fs/ ipc/ security/ crypto/
567 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
568 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
569 $(net-y) $(net-m) $(libs-y) $(libs-m)))
571 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
573 $(core-n) $(core-) $(drivers-n) $(drivers-) \
574 $(net-n) $(net-) $(libs-n) $(libs-))))
576 init-y := $(patsubst %/, %/built-in.o, $(init-y))
577 core-y := $(patsubst %/, %/built-in.o, $(core-y))
578 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
579 net-y := $(patsubst %/, %/built-in.o, $(net-y))
580 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
581 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
582 libs-y := $(libs-y1) $(libs-y2)
585 # ---------------------------------------------------------------------------
586 # vmlinux is build from the objects selected by $(vmlinux-init) and
587 # $(vmlinux-main). Most are built-in.o files from top-level directories
588 # in the kernel tree, others are specified in arch/$(ARCH)Makefile.
589 # Ordering when linking is important, and $(vmlinux-init) must be first.
594 # +-< $(vmlinux-init)
595 # | +--< init/version.o + more
597 # +--< $(vmlinux-main)
598 # | +--< driver/built-in.o mm/built-in.o + more
600 # +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
602 # vmlinux version (uname -v) cannot be updated during normal
603 # descending-into-subdirs phase since we do not yet know if we need to
605 # Therefore this step is delayed until just before final link of vmlinux -
606 # except in the kallsyms case where it is done just before adding the
607 # symbols to the kernel.
609 # System.map is generated to document addresses of all kernel symbols
611 vmlinux-init := $(head-y) $(init-y)
612 vmlinux-main := $(core-y) $(libs-y) $(drivers-y) $(net-y)
613 vmlinux-all := $(vmlinux-init) $(vmlinux-main)
614 vmlinux-lds := arch/$(ARCH)/kernel/vmlinux.lds
616 # Rule to link vmlinux - also used during CONFIG_KALLSYMS
617 # May be overridden by arch/$(ARCH)/Makefile
618 quiet_cmd_vmlinux__ ?= LD $@
619 cmd_vmlinux__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) -o $@ \
620 -T $(vmlinux-lds) $(vmlinux-init) \
621 --start-group $(vmlinux-main) --end-group \
622 $(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) FORCE ,$^)
624 # Generate new vmlinux version
625 quiet_cmd_vmlinux_version = GEN .version
626 cmd_vmlinux_version = set -e; \
627 . $(srctree)/scripts/mkversion > .tmp_version; \
628 mv -f .tmp_version .version; \
629 $(MAKE) $(build)=init
631 # Generate System.map
632 quiet_cmd_sysmap = SYSMAP
633 cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap
636 # If CONFIG_KALLSYMS is set .version is already updated
637 # Generate System.map and verify that the content is consistent
639 define rule_vmlinux__
640 $(if $(CONFIG_KALLSYMS),,+$(call cmd,vmlinux_version))
642 $(call cmd,vmlinux__)
643 $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
645 $(Q)$(if $($(quiet)cmd_sysmap), \
646 echo ' $($(quiet)cmd_sysmap) System.map' &&) \
647 $(cmd_sysmap) $@ System.map; \
648 if [ $$? -ne 0 ]; then \
656 ifdef CONFIG_KALLSYMS
657 # Generate section listing all symbols and add it into vmlinux $(kallsyms.o)
658 # It's a three stage process:
659 # o .tmp_vmlinux1 has all symbols and sections, but __kallsyms is
661 # Running kallsyms on that gives us .tmp_kallsyms1.o with
662 # the right size - vmlinux version (uname -v) is updated during this step
663 # o .tmp_vmlinux2 now has a __kallsyms section of the right size,
664 # but due to the added section, some addresses have shifted.
665 # From here, we generate a correct .tmp_kallsyms2.o
666 # o The correct .tmp_kallsyms2.o is linked into the final vmlinux.
667 # o Verify that the System.map from vmlinux matches the map from
668 # .tmp_vmlinux2, just in case we did not generate kallsyms correctly.
669 # o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
670 # .tmp_vmlinux3 and .tmp_kallsyms3.o. This is only meant as a
671 # temporary bypass to allow the kernel to be built while the
672 # maintainers work out what went wrong with kallsyms.
674 ifdef CONFIG_KALLSYMS_EXTRA_PASS
680 kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
682 define verify_kallsyms
683 $(Q)$(if $($(quiet)cmd_sysmap), \
684 echo ' $($(quiet)cmd_sysmap) .tmp_System.map' &&) \
685 $(cmd_sysmap) .tmp_vmlinux$(last_kallsyms) .tmp_System.map
686 $(Q)cmp -s System.map .tmp_System.map || \
687 (echo Inconsistent kallsyms data; \
688 echo Try setting CONFIG_KALLSYMS_EXTRA_PASS; \
689 rm .tmp_kallsyms* ; /bin/false )
692 # Update vmlinux version before link
693 # Use + in front of this rule to silent warning about make -j1
694 cmd_ksym_ld = $(cmd_vmlinux__)
696 +$(call cmd,vmlinux_version)
697 $(call cmd,vmlinux__)
698 $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
701 # Generate .S file with all kernel symbols
702 quiet_cmd_kallsyms = KSYM $@
703 cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
704 $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
706 .tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
707 $(call if_changed_dep,as_o_S)
709 .tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
712 # .tmp_vmlinux1 must be complete except kallsyms, so update vmlinux version
713 .tmp_vmlinux1: $(vmlinux-lds) $(vmlinux-all) FORCE
714 $(call if_changed_rule,ksym_ld)
716 .tmp_vmlinux2: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms1.o FORCE
717 $(call if_changed,vmlinux__)
719 .tmp_vmlinux3: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms2.o FORCE
720 $(call if_changed,vmlinux__)
722 # Needs to visit scripts/ before $(KALLSYMS) can be used.
723 $(KALLSYMS): scripts ;
725 endif # ifdef CONFIG_KALLSYMS
727 # vmlinux image - including updated kernel symbols
728 vmlinux: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) $(kallsyms.o) FORCE
729 $(call if_changed_rule,vmlinux__)
731 # The actual objects are generated when descending,
732 # make sure no implicit rule kicks in
733 $(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(vmlinux-dirs) ;
735 # Handle descending into subdirectories listed in $(vmlinux-dirs)
736 # Preset locale variables to speed up the build process. Limit locale
737 # tweaks to this spot to avoid wrong language settings when running
738 # make menuconfig etc.
739 # Error messages still appears in the original language
741 .PHONY: $(vmlinux-dirs)
742 $(vmlinux-dirs): prepare-all scripts
743 $(Q)$(MAKE) $(build)=$@
745 # Things we need to do before we recursively start building the kernel
746 # or the modules are listed in "prepare-all".
747 # A multi level approach is used. prepare1 is updated first, then prepare0.
748 # prepare-all is the collection point for the prepare targets.
750 .PHONY: prepare-all prepare prepare0 prepare1 prepare2
752 # prepare2 is used to check if we are building in a separate output directory,
754 # 1) Check that make has not been executed in the kernel src $(srctree)
755 # 2) Create the include2 directory, used for the second asm symlink
758 ifneq ($(KBUILD_SRC),)
759 @echo ' Using $(srctree) as source for kernel'
760 $(Q)if [ -h $(srctree)/include/asm -o -f $(srctree)/.config ]; then \
761 echo " $(srctree) is not clean, please run 'make mrproper'";\
762 echo " in the '$(srctree)' directory.";\
765 $(Q)if [ ! -d include2 ]; then mkdir -p include2; fi;
766 $(Q)ln -fsn $(srctree)/include/asm-$(ARCH) include2/asm
769 # prepare1 creates a makefile if using a separate output directory
770 prepare1: prepare2 outputmakefile
772 prepare0: prepare1 include/linux/version.h include/asm include/config/MARKER
773 ifneq ($(KBUILD_MODULES),)
774 $(Q)rm -rf $(MODVERDIR)
775 $(Q)mkdir -p $(MODVERDIR)
778 # All the preparing..
779 prepare-all: prepare0 prepare
781 # Leave this as default for preprocessing vmlinux.lds.S, which is now
782 # done in arch/$(ARCH)/kernel/Makefile
784 export CPPFLAGS_vmlinux.lds += -P -C -U$(ARCH)
787 # ---------------------------------------------------------------------------
789 %.s: %.c scripts FORCE
790 $(Q)$(MAKE) $(build)=$(@D) $@
791 %.i: %.c scripts FORCE
792 $(Q)$(MAKE) $(build)=$(@D) $@
793 %.o: %.c scripts FORCE
794 $(Q)$(MAKE) $(build)=$(@D) $@
796 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) $(build)=$(@D) $(@:.ko=.o)
797 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
798 %/: scripts prepare FORCE
799 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) $(build)=$(@D)
800 %.lst: %.c scripts FORCE
801 $(Q)$(MAKE) $(build)=$(@D) $@
802 %.s: %.S scripts FORCE
803 $(Q)$(MAKE) $(build)=$(@D) $@
804 %.o: %.S scripts FORCE
805 $(Q)$(MAKE) $(build)=$(@D) $@
807 # FIXME: The asm symlink changes when $(ARCH) changes. That's
808 # hard to detect, but I suppose "make mrproper" is a good idea
809 # before switching between archs anyway.
812 @echo ' SYMLINK $@ -> include/asm-$(ARCH)'
813 $(Q)if [ ! -d include ]; then mkdir -p include; fi;
814 @ln -fsn asm-$(ARCH) $@
816 # Split autoconf.h into include/linux/config/*
818 include/config/MARKER: include/linux/autoconf.h
819 @echo ' SPLIT include/linux/autoconf.h -> include/config/*'
820 @scripts/basic/split-include include/linux/autoconf.h include/config
823 # Generate some files
824 # ---------------------------------------------------------------------------
826 # KERNELRELEASE can change from a few different places, meaning version.h
827 # needs to be updated, so this check is forced on all builds
831 define filechk_version.h
832 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
833 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
836 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"; \
837 echo \#define LINUX_VERSION_CODE `expr $(VERSION) \\* 65536 + $(PATCHLEVEL) \\* 256 + $(SUBLEVEL)`; \
838 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'; \
842 include/linux/version.h: $(srctree)/Makefile FORCE
843 $(call filechk,version.h)
845 # ---------------------------------------------------------------------------
849 @echo '*** Warning: make $@ is unnecessary now.'
851 # ---------------------------------------------------------------------------
856 # By default, build modules as well
863 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux)
864 @echo ' Building modules, stage 2.';
865 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
868 # Target to prepare building external modules
869 .PHONY: modules_prepare
870 modules_prepare: prepare-all scripts
872 # Target to install modules
873 .PHONY: modules_install
874 modules_install: _modinst_ _modinst_post
878 @if [ -z "`$(DEPMOD) -V | grep module-init-tools`" ]; then \
879 echo "Warning: you may need to install module-init-tools"; \
880 echo "See http://www.codemonkey.org.uk/docs/post-halloween-2.6.txt";\
883 @rm -rf $(MODLIB)/kernel
884 @rm -f $(MODLIB)/source
885 @mkdir -p $(MODLIB)/kernel
886 @ln -s $(srctree) $(MODLIB)/source
887 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
888 rm -f $(MODLIB)/build ; \
889 ln -s $(objtree) $(MODLIB)/build ; \
891 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modinst
893 # If System.map exists, run depmod. This deliberately does not have a
894 # dependency on System.map since that would run the dependency tree on
895 # vmlinux. This depmod is only for convenience to give the initial
896 # boot a modules.dep even before / is mounted read-write. However the
897 # boot script depmod is the master version.
898 ifeq "$(strip $(INSTALL_MOD_PATH))" ""
901 depmod_opts := -b $(INSTALL_MOD_PATH) -r
903 .PHONY: _modinst_post
904 _modinst_post: _modinst_
905 if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
907 else # CONFIG_MODULES
909 # Modules not configured
910 # ---------------------------------------------------------------------------
912 modules modules_install: FORCE
914 @echo "The present kernel configuration has modules disabled."
915 @echo "Type 'make config' and enable loadable module support."
916 @echo "Then build a kernel with module support enabled."
920 endif # CONFIG_MODULES
922 # Generate asm-offsets.h
923 # ---------------------------------------------------------------------------
925 define filechk_gen-asm-offsets
927 echo "#ifndef __ASM_OFFSETS_H__"; \
928 echo "#define __ASM_OFFSETS_H__"; \
930 echo " * DO NOT MODIFY."; \
932 echo " * This file was generated by arch/$(ARCH)/Makefile"; \
936 sed -ne "/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}"; \
943 # Cleaning is done on three levels.
944 # make clean Delete most generated files
945 # Leave enough to build external modules
946 # make mrproper Delete the current configuration, and all generated files
947 # make distclean Remove editor backup files, patch leftover files and the like
949 # Directories & files removed with 'make clean'
950 CLEAN_DIRS += $(MODVERDIR)
951 CLEAN_FILES += vmlinux System.map \
952 .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map
954 # Directories & files removed with 'make mrproper'
955 MRPROPER_DIRS += include/config include2
956 MRPROPER_FILES += .config .config.old include/asm .version \
957 include/linux/autoconf.h include/linux/version.h \
958 Module.symvers tags TAGS cscope*
960 # clean - Delete most, but leave enough to build external modules
962 clean: rm-dirs := $(CLEAN_DIRS)
963 clean: rm-files := $(CLEAN_FILES)
964 clean-dirs := $(addprefix _clean_,$(vmlinux-alldirs))
966 .PHONY: $(clean-dirs) clean archclean
968 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
970 clean: archclean $(clean-dirs)
973 @find . $(RCS_FIND_IGNORE) \
974 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
975 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
976 -type f -print | xargs rm -f
978 # mrproper - Delete all generated files, including .config
980 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
981 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
982 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
984 .PHONY: $(mrproper-dirs) mrproper archmrproper
986 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
988 mrproper: clean archmrproper $(mrproper-dirs)
997 @find $(srctree) $(RCS_FIND_IGNORE) \
998 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
999 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1000 -o -name '.*.rej' -o -size 0 \
1001 -o -name '*%' -o -name '.*.cmd' -o -name 'core' \) \
1002 -type f -print | xargs rm -f
1005 # Packaging of the kernel to various formats
1006 # ---------------------------------------------------------------------------
1007 # rpm target kept for backward compatibility
1008 package-dir := $(srctree)/scripts/package
1013 $(Q)$(MAKE) -f $(package-dir)/Makefile $@
1015 $(Q)$(MAKE) -f $(package-dir)/Makefile $@
1018 # Brief documentation of the typical targets used
1019 # ---------------------------------------------------------------------------
1021 boards := $(wildcard $(srctree)/arch/$(ARCH)/configs/*_defconfig)
1022 boards := $(notdir $(boards))
1025 @echo 'Cleaning targets:'
1026 @echo ' clean - remove most generated files but keep the config'
1027 @echo ' mrproper - remove all generated files + config + various backup files'
1029 @echo 'Configuration targets:'
1030 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1032 @echo 'Other generic targets:'
1033 @echo ' all - Build all targets marked with [*]'
1034 @echo '* vmlinux - Build the bare kernel'
1035 @echo '* modules - Build all modules'
1036 @echo ' modules_install - Install all modules'
1037 @echo ' dir/ - Build all files in dir and below'
1038 @echo ' dir/file.[ois] - Build specified target only'
1039 @echo ' dir/file.ko - Build module including final link'
1040 @echo ' rpm - Build a kernel as an RPM package'
1041 @echo ' tags/TAGS - Generate tags file for editors'
1042 @echo ' cscope - Generate cscope index'
1044 @echo 'Static analysers'
1045 @echo ' buildcheck - List dangling references to vmlinux discarded sections'
1046 @echo ' and init sections from non-init sections'
1047 @echo ' checkstack - Generate a list of stack hogs'
1048 @echo ' namespacecheck - Name space analysis on compiled kernel'
1050 @echo 'Kernel packaging:'
1051 @$(MAKE) -f $(package-dir)/Makefile help
1053 @echo 'Documentation targets:'
1054 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1056 @echo 'Architecture specific targets ($(ARCH)):'
1057 @$(if $(archhelp),$(archhelp),\
1058 echo ' No architecture specific help defined for $(ARCH)')
1061 $(foreach b, $(boards), \
1062 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1065 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1066 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1067 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse)'
1068 @echo ' make C=2 [targets] Force check of all c source with $$CHECK (sparse)'
1070 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1071 @echo 'For further info see the ./README file'
1074 # Documentation targets
1075 # ---------------------------------------------------------------------------
1076 %docs: scripts_basic FORCE
1077 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1079 else # KBUILD_EXTMOD
1082 # External module support.
1083 # When building external modules the kernel used as basis is considered
1084 # read-only, and no consistency checks are made and the make
1085 # system is not used on the basis kernel. If updates are required
1086 # in the basis kernel ordinary make commands (without M=...) must
1089 # The following are the only valid targets when building external
1091 # make M=dir clean Delete all automatically generated files
1092 # make M=dir modules Make all modules in specified dir
1093 # make M=dir Same as 'make M=dir modules'
1094 # make M=dir modules_install
1095 # Install the modules build in the module directory
1096 # Assumes install directory is already created
1098 # We are always building modules
1102 $(Q)mkdir -p $(MODVERDIR)
1104 .PHONY: $(objtree)/Module.symvers
1105 $(objtree)/Module.symvers:
1106 @test -e $(objtree)/Module.symvers || ( \
1108 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1109 echo " is missing; modules will have no dependencies and modversions."; \
1112 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1113 .PHONY: $(module-dirs) modules
1114 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1115 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1117 modules: $(module-dirs)
1118 @echo ' Building modules, stage 2.';
1119 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
1121 .PHONY: modules_install
1123 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modinst
1125 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1127 .PHONY: $(clean-dirs) clean
1129 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1131 clean: rm-dirs := $(MODVERDIR)
1132 clean: $(clean-dirs)
1134 @find $(KBUILD_EXTMOD) $(RCS_FIND_IGNORE) \
1135 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1136 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
1137 -type f -print | xargs rm -f
1140 @echo ' Building external modules.'
1141 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1143 @echo ' modules - default target, build the module(s)'
1144 @echo ' modules_install - install the module'
1145 @echo ' clean - remove generated files in module directory only'
1147 endif # KBUILD_EXTMOD
1149 # Generate tags for editors
1150 # ---------------------------------------------------------------------------
1152 #We want __srctree to totally vanish out when KBUILD_OUTPUT is not set
1153 #(which is the most common case IMHO) to avoid unneeded clutter in the big tags file.
1154 #Adding $(srctree) adds about 20M on i386 to the size of the output file!
1156 ifeq ($(src),$(obj))
1159 __srctree = $(srctree)/
1163 ( find $(__srctree) $(RCS_FIND_IGNORE) \
1164 \( -name include -o -name arch \) -prune -o \
1165 -name '*.[chS]' -print; \
1166 find $(__srctree)arch/$(ARCH) $(RCS_FIND_IGNORE) \
1167 -name '*.[chS]' -print; \
1168 find $(__srctree)security/selinux/include $(RCS_FIND_IGNORE) \
1169 -name '*.[chS]' -print; \
1170 find $(__srctree)include $(RCS_FIND_IGNORE) \
1171 \( -name config -o -name 'asm-*' \) -prune \
1172 -o -name '*.[chS]' -print; \
1173 find $(__srctree)include/asm-$(ARCH) $(RCS_FIND_IGNORE) \
1174 -name '*.[chS]' -print; \
1175 find $(__srctree)include/asm-generic $(RCS_FIND_IGNORE) \
1176 -name '*.[chS]' -print )
1179 quiet_cmd_cscope-file = FILELST cscope.files
1180 cmd_cscope-file = $(all-sources) > cscope.files
1182 quiet_cmd_cscope = MAKE cscope.out
1183 cmd_cscope = cscope -k -b -q
1186 $(call cmd,cscope-file)
1189 quiet_cmd_TAGS = MAKE $@
1190 cmd_TAGS = $(all-sources) | etags -
1192 # Exuberant ctags works better with -I
1194 quiet_cmd_tags = MAKE $@
1197 CTAGSF=`ctags --version | grep -i exuberant >/dev/null && echo "-I __initdata,__exitdata,EXPORT_SYMBOL,EXPORT_SYMBOL_GPL --extra=+f"`; \
1198 $(all-sources) | xargs ctags $$CTAGSF -a
1208 # Scripts to check various things for consistency
1209 # ---------------------------------------------------------------------------
1212 find * $(RCS_FIND_IGNORE) \
1213 -name '*.[hcS]' -type f -print | sort \
1214 | xargs $(PERL) -w scripts/checkconfig.pl
1217 find * $(RCS_FIND_IGNORE) \
1218 -name '*.[hcS]' -type f -print | sort \
1219 | xargs $(PERL) -w scripts/checkincludes.pl
1222 find * $(RCS_FIND_IGNORE) \
1223 -name '*.[hcS]' -type f -print | sort \
1224 | xargs $(PERL) -w scripts/checkversion.pl
1227 $(PERL) $(srctree)/scripts/reference_discarded.pl
1228 $(PERL) $(srctree)/scripts/reference_init.pl
1231 $(PERL) $(srctree)/scripts/namespace.pl
1233 endif #ifeq ($(config-targets),1)
1234 endif #ifeq ($(mixed-targets),1)
1238 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1239 $(PERL) $(src)/scripts/checkstack.pl $(ARCH)
1242 @echo $(KERNELRELEASE)
1244 # FIXME Should go into a make.lib or something
1245 # ===========================================================================
1247 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1248 cmd_rmdirs = rm -rf $(rm-dirs)
1250 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1251 cmd_rmfiles = rm -f $(rm-files)
1254 a_flags = -Wp,-MD,$(depfile) $(AFLAGS) $(AFLAGS_KERNEL) \
1255 $(NOSTDINC_FLAGS) $(CPPFLAGS) \
1256 $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
1258 quiet_cmd_as_o_S = AS $@
1259 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
1261 # read all saved command lines
1263 targets := $(wildcard $(sort $(targets)))
1264 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1266 ifneq ($(cmd_files),)
1267 $(cmd_files): ; # Do not try to update included dependency files
1268 include $(cmd_files)
1271 # Execute command and generate cmd file
1272 if_changed = $(if $(strip $? \
1273 $(filter-out $(cmd_$(1)),$(cmd_$@))\
1274 $(filter-out $(cmd_$@),$(cmd_$(1)))),\
1276 $(if $($(quiet)cmd_$(1)),echo ' $(subst ','\'',$($(quiet)cmd_$(1)))';) \
1278 echo 'cmd_$@ := $(subst $$,$$$$,$(subst ','\'',$(cmd_$(1))))' > $(@D)/.$(@F).cmd)
1281 # execute the command and also postprocess generated .d dependencies
1283 if_changed_dep = $(if $(strip $? $(filter-out FORCE $(wildcard $^),$^)\
1284 $(filter-out $(cmd_$(1)),$(cmd_$@))\
1285 $(filter-out $(cmd_$@),$(cmd_$(1)))),\
1287 $(if $($(quiet)cmd_$(1)),echo ' $(subst ','\'',$($(quiet)cmd_$(1)))';) \
1289 scripts/basic/fixdep $(depfile) $@ '$(subst $$,$$$$,$(subst ','\'',$(cmd_$(1))))' > $(@D)/.$(@F).tmp; \
1291 mv -f $(@D)/.$(@F).tmp $(@D)/.$(@F).cmd)
1293 # Usage: $(call if_changed_rule,foo)
1294 # will check if $(cmd_foo) changed, or any of the prequisites changed,
1295 # and if so will execute $(rule_foo)
1297 if_changed_rule = $(if $(strip $? \
1298 $(filter-out $(cmd_$(1)),$(cmd_$(@F)))\
1299 $(filter-out $(cmd_$(@F)),$(cmd_$(1)))),\
1302 # If quiet is set, only print short version of command
1304 cmd = @$(if $($(quiet)cmd_$(1)),echo ' $($(quiet)cmd_$(1))' &&) $(cmd_$(1))
1306 # filechk is used to check if the content of a generated file is updated.
1308 # define filechk_sample
1309 # echo $KERNELRELEASE
1311 # version.h : Makefile
1312 # $(call filechk,sample)
1313 # The rule defined shall write to stdout the content of the new file.
1314 # The existing file will be compared with the new one.
1315 # - If no file exist it is created
1316 # - If the content differ the new file is used
1317 # - If they are equal no change, and no timestamp update
1322 mkdir -p $(dir $@); \
1323 $(filechk_$(1)) < $< > $@.tmp; \
1324 if [ -r $@ ] && cmp -s $@ $@.tmp; then \
1332 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=dir
1334 # $(Q)$(MAKE) $(build)=dir
1335 build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj
1337 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir
1339 # $(Q)$(MAKE) $(clean)=dir
1340 clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
1342 # $(call descend,<dir>,<target>)
1343 # Recursively call a sub-make in <dir> with target <target>
1344 # Usage is deprecated, because make does not see this as an invocation of make.
1345 descend =$(Q)$(MAKE) -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj=$(1) $(2)
1347 endif # skip-makefile