kbuild: fix segfault in modpost
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / Makefile
CommitLineData
1da177e4
LT
1VERSION = 2
2PATCHLEVEL = 6
f695baf2 3SUBLEVEL = 23
bbf25010 4EXTRAVERSION =
81cfe79b 5NAME = Arr Matey! A Hairy Bilge Rat!
1da177e4
LT
6
7# *DOCUMENTATION*
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.
12
15964864
OV
13# Do not:
14# o use make's built-in rules and variables
15# (this increases performance and avoid hard-to-debug behavour);
16# o print "Entering directory ...";
17MAKEFLAGS += -rR --no-print-directory
1da177e4
LT
18
19# We are using a recursive build, so we need to do a little thinking
20# to get the ordering right.
21#
22# Most importantly: sub-Makefiles should only ever modify files in
23# their own directory. If in some directory we have a dependency on
24# a file in another dir (which doesn't happen often, but it's often
25# unavoidable when linking the built-in.o targets which finally
26# turn into vmlinux), we will call a sub make in that other dir, and
27# after that we are sure that everything which is in that other dir
28# is now up to date.
29#
30# The only cases where we need to modify files which have global
31# effects are thus separated out and done before the recursive
32# descending is started. They are now explicitly listed as the
33# prepare rule.
34
35# To put more focus on warnings, be less verbose as default
36# Use 'make V=1' to see the full commands
37
38ifdef V
39 ifeq ("$(origin V)", "command line")
40 KBUILD_VERBOSE = $(V)
41 endif
42endif
43ifndef KBUILD_VERBOSE
44 KBUILD_VERBOSE = 0
45endif
46
1c7bafe7
RD
47# Call a source code checker (by default, "sparse") as part of the
48# C compilation.
49#
50# Use 'make C=1' to enable checking of only re-compiled files.
51# Use 'make C=2' to enable checking of *all* source files, regardless
52# of whether they are re-compiled or not.
53#
54# See the file "Documentation/sparse.txt" for more details, including
55# where to get the "sparse" utility.
1da177e4
LT
56
57ifdef C
58 ifeq ("$(origin C)", "command line")
59 KBUILD_CHECKSRC = $(C)
60 endif
61endif
62ifndef KBUILD_CHECKSRC
63 KBUILD_CHECKSRC = 0
64endif
65
66# Use make M=dir to specify directory of external module to build
67# Old syntax make ... SUBDIRS=$PWD is still supported
68# Setting the environment variable KBUILD_EXTMOD take precedence
69ifdef SUBDIRS
70 KBUILD_EXTMOD ?= $(SUBDIRS)
71endif
72ifdef M
73 ifeq ("$(origin M)", "command line")
74 KBUILD_EXTMOD := $(M)
75 endif
76endif
77
78
79# kbuild supports saving output files in a separate directory.
80# To locate output files in a separate directory two syntaxes are supported.
81# In both cases the working directory must be the root of the kernel src.
82# 1) O=
83# Use "make O=dir/to/store/output/files/"
070b98bf 84#
1da177e4
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85# 2) Set KBUILD_OUTPUT
86# Set the environment variable KBUILD_OUTPUT to point to the directory
87# where the output files shall be placed.
88# export KBUILD_OUTPUT=dir/to/store/output/files/
89# make
90#
91# The O= assignment takes precedence over the KBUILD_OUTPUT environment
92# variable.
93
94
95# KBUILD_SRC is set on invocation of make in OBJ directory
96# KBUILD_SRC is not intended to be used by the regular user (for now)
97ifeq ($(KBUILD_SRC),)
98
99# OK, Make called in directory where kernel src resides
100# Do we want to locate output files in a separate directory?
101ifdef O
102 ifeq ("$(origin O)", "command line")
103 KBUILD_OUTPUT := $(O)
104 endif
105endif
106
107# That's our default target when none is given on the command line
4f193362 108PHONY := _all
1da177e4
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109_all:
110
111ifneq ($(KBUILD_OUTPUT),)
112# Invoke a second make in the output directory, passing relevant variables
113# check that the output directory actually exists
114saved-output := $(KBUILD_OUTPUT)
115KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
116$(if $(KBUILD_OUTPUT),, \
117 $(error output directory "$(saved-output)" does not exist))
118
4f193362 119PHONY += $(MAKECMDGOALS)
1da177e4 120
36cbbe5e 121$(filter-out _all,$(MAKECMDGOALS)) _all:
23a45e2c
SR
122 $(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
123 KBUILD_SRC=$(CURDIR) \
36cbbe5e 124 KBUILD_EXTMOD="$(KBUILD_EXTMOD)" -f $(CURDIR)/Makefile $@
1da177e4
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125
126# Leave processing to above invocation of make
127skip-makefile := 1
128endif # ifneq ($(KBUILD_OUTPUT),)
129endif # ifeq ($(KBUILD_SRC),)
130
131# We process the rest of the Makefile if this is the final invocation of make
132ifeq ($(skip-makefile),)
133
134# If building an external module we do not care about the all: rule
135# but instead _all depend on modules
4f193362 136PHONY += all
1da177e4
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137ifeq ($(KBUILD_EXTMOD),)
138_all: all
139else
140_all: modules
141endif
142
143srctree := $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
144TOPDIR := $(srctree)
145# FIXME - TOPDIR is obsolete, use srctree/objtree
146objtree := $(CURDIR)
147src := $(srctree)
148obj := $(objtree)
149
0f558c33 150VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
1da177e4
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151
152export srctree objtree VPATH TOPDIR
153
1da177e4
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154
155# SUBARCH tells the usermode build what the underlying arch is. That is set
156# first, and if a usermode build is happening, the "ARCH=um" on the command
157# line overrides the setting of ARCH below. If a native build is happening,
158# then ARCH is assigned, getting whatever value it gets normally, and
159# SUBARCH is subsequently ignored.
160
161SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
162 -e s/arm.*/arm/ -e s/sa110/arm/ \
39990b5e 163 -e s/s390x/s390/ -e s/parisc64/parisc/ \
8999257c 164 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ )
1da177e4
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165
166# Cross compiling and selecting different set of gcc/bin-utils
167# ---------------------------------------------------------------------------
168#
169# When performing cross compilation for other architectures ARCH shall be set
170# to the target architecture. (See arch/* for the possibilities).
171# ARCH can be set during invocation of make:
172# make ARCH=ia64
173# Another way is to have ARCH set in the environment.
174# The default ARCH is the host where make is executed.
175
176# CROSS_COMPILE specify the prefix used for all executables used
177# during compilation. Only gcc and related bin-utils executables
178# are prefixed with $(CROSS_COMPILE).
179# CROSS_COMPILE can be set on the command line
180# make CROSS_COMPILE=ia64-linux-
181# Alternatively CROSS_COMPILE can be set in the environment.
182# Default value for CROSS_COMPILE is not to prefix executables
183# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
184
185ARCH ?= $(SUBARCH)
186CROSS_COMPILE ?=
187
188# Architecture as present in compile.h
6752ed90
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189UTS_MACHINE := $(ARCH)
190SRCARCH := $(ARCH)
1da177e4 191
14cdd3c4
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192KCONFIG_CONFIG ?= .config
193
1da177e4
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194# SHELL used by kbuild
195CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
196 else if [ -x /bin/bash ]; then echo /bin/bash; \
197 else echo sh; fi ; fi)
198
070b98bf
SR
199HOSTCC = gcc
200HOSTCXX = g++
201HOSTCFLAGS = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer
202HOSTCXXFLAGS = -O2
1da177e4 203
070b98bf
SR
204# Decide whether to build built-in, modular, or both.
205# Normally, just do built-in.
1da177e4
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206
207KBUILD_MODULES :=
208KBUILD_BUILTIN := 1
209
210# If we have only "make modules", don't compile built-in objects.
211# When we're building modules with modversions, we need to consider
212# the built-in objects during the descend as well, in order to
070b98bf 213# make sure the checksums are up to date before we record them.
1da177e4
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214
215ifeq ($(MAKECMDGOALS),modules)
216 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
217endif
218
219# If we have "make <whatever> modules", compile modules
220# in addition to whatever we do anyway.
221# Just "make" or "make all" shall build modules as well
222
223ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
224 KBUILD_MODULES := 1
225endif
226
227ifeq ($(MAKECMDGOALS),)
228 KBUILD_MODULES := 1
229endif
230
e579d351 231export KBUILD_MODULES KBUILD_BUILTIN
1da177e4
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232export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
233
234# Beautify output
235# ---------------------------------------------------------------------------
236#
237# Normally, we echo the whole command before executing it. By making
238# that echo $($(quiet)$(cmd)), we now have the possibility to set
239# $(quiet) to choose other forms of output instead, e.g.
240#
241# quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
242# cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
243#
244# If $(quiet) is empty, the whole command will be printed.
245# If it is set to "quiet_", only the short version will be printed.
070b98bf 246# If it is set to "silent_", nothing will be printed at all, since
1da177e4
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247# the variable $(silent_cmd_cc_o_c) doesn't exist.
248#
a58a414f 249# A simple variant is to prefix commands with $(Q) - that's useful
1da177e4
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250# for commands that shall be hidden in non-verbose mode.
251#
252# $(Q)ln $@ :<
253#
254# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
255# If KBUILD_VERBOSE equals 1 then the above command is displayed.
256
257ifeq ($(KBUILD_VERBOSE),1)
258 quiet =
259 Q =
260else
261 quiet=quiet_
262 Q = @
263endif
264
265# If the user is running make -s (silent mode), suppress echoing of
266# commands
267
268ifneq ($(findstring s,$(MAKEFLAGS)),)
269 quiet=silent_
270endif
271
272export quiet Q KBUILD_VERBOSE
273
1da177e4
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274
275# Look for make include files relative to root of kernel src
276MAKEFLAGS += --include-dir=$(srctree)
277
15964864
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278# We need some generic definitions.
279include $(srctree)/scripts/Kbuild.include
1da177e4
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280
281# Make variables (CC, etc...)
282
283AS = $(CROSS_COMPILE)as
284LD = $(CROSS_COMPILE)ld
285CC = $(CROSS_COMPILE)gcc
286CPP = $(CC) -E
287AR = $(CROSS_COMPILE)ar
288NM = $(CROSS_COMPILE)nm
289STRIP = $(CROSS_COMPILE)strip
290OBJCOPY = $(CROSS_COMPILE)objcopy
291OBJDUMP = $(CROSS_COMPILE)objdump
292AWK = awk
293GENKSYMS = scripts/genksyms/genksyms
294DEPMOD = /sbin/depmod
295KALLSYMS = scripts/kallsyms
296PERL = perl
297CHECK = sparse
298
af4ca457 299CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ -Wbitwise $(CF)
1da177e4
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300MODFLAGS = -DMODULE
301CFLAGS_MODULE = $(MODFLAGS)
302AFLAGS_MODULE = $(MODFLAGS)
114f5157 303LDFLAGS_MODULE =
1da177e4
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304CFLAGS_KERNEL =
305AFLAGS_KERNEL =
306
307
308# Use LINUXINCLUDE when you must reference the include/ directory.
309# Needed to be compatible with the O= option
310LINUXINCLUDE := -Iinclude \
2dd34b48 311 $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include) \
e623a3b8 312 -include include/linux/autoconf.h
1da177e4
LT
313
314CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE)
315
070b98bf 316CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
94bed2a9
DJ
317 -fno-strict-aliasing -fno-common \
318 -Werror-implicit-function-declaration
070b98bf 319AFLAGS := -D__ASSEMBLY__
1da177e4 320
f1d28fb0
RZ
321# Read KERNELRELEASE from include/config/kernel.release (if it exists)
322KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
2244cbd8 323KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
cb58455c 324
070b98bf 325export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
6752ed90 326export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
070b98bf
SR
327export CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE
328export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
1da177e4
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329
330export CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
070b98bf 331export CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
1da177e4
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332export AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
333
334# When compiling out-of-tree modules, put MODVERDIR in the module
335# tree rather than in the kernel tree. The kernel tree might
336# even be read-only.
337export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
338
1da177e4
LT
339# Files to ignore in find ... statements
340
406119f4
TM
341RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS -o -name .pc -o -name .hg -o -name .git \) -prune -o
342export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn --exclude CVS --exclude .pc --exclude .hg --exclude .git
1da177e4
LT
343
344# ===========================================================================
345# Rules shared between *config targets and build targets
346
347# Basic helpers built in scripts/
4f193362 348PHONY += scripts_basic
1da177e4
LT
349scripts_basic:
350 $(Q)$(MAKE) $(build)=scripts/basic
351
cd05e6bd
JB
352# To avoid any implicit rule to kick in, define an empty command.
353scripts/basic/%: scripts_basic ;
354
4f193362 355PHONY += outputmakefile
fd5f0cd6
JB
356# outputmakefile generates a Makefile in the output directory, if using a
357# separate output directory. This allows convenient use of make in the
358# output directory.
1da177e4 359outputmakefile:
fd5f0cd6
JB
360ifneq ($(KBUILD_SRC),)
361 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
362 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
363endif
1da177e4
LT
364
365# To make sure we do not include .config for any of the *config targets
366# catch them early, and hand them over to scripts/kconfig/Makefile
367# It is allowed to specify more targets when calling make, including
368# mixing *config targets and build targets.
070b98bf 369# For example 'make oldconfig all'.
1da177e4
LT
370# Detect when mixed targets is specified, and make a second invocation
371# of make so .config is not included in this case either (for *config).
372
3eb3c740 373no-dot-config-targets := clean mrproper distclean \
c30a02e0 374 cscope TAGS tags help %docs check% \
3eb3c740
RZ
375 include/linux/version.h headers_% \
376 kernelrelease kernelversion
1da177e4
LT
377
378config-targets := 0
379mixed-targets := 0
380dot-config := 1
381
382ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
383 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
384 dot-config := 0
385 endif
386endif
387
388ifeq ($(KBUILD_EXTMOD),)
389 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
390 config-targets := 1
391 ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
392 mixed-targets := 1
393 endif
394 endif
395endif
396
397ifeq ($(mixed-targets),1)
398# ===========================================================================
399# We're called with mixed targets (*config and build targets).
400# Handle them one by one.
401
402%:: FORCE
403 $(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@
404
405else
406ifeq ($(config-targets),1)
407# ===========================================================================
408# *config targets only - make sure prerequisites are updated, and descend
409# in scripts/kconfig to make the *config target
410
411# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
412# KBUILD_DEFCONFIG may point out an alternative default configuration
413# used for 'make defconfig'
414include $(srctree)/arch/$(ARCH)/Makefile
415export KBUILD_DEFCONFIG
416
cd05e6bd 417config %config: scripts_basic outputmakefile FORCE
c955ccaf 418 $(Q)mkdir -p include/linux include/config
1da177e4
LT
419 $(Q)$(MAKE) $(build)=scripts/kconfig $@
420
421else
422# ===========================================================================
423# Build targets only - this includes vmlinux, arch specific targets, clean
424# targets and others. In general all targets except *config targets.
425
426ifeq ($(KBUILD_EXTMOD),)
427# Additional helpers built in scripts/
428# Carefully list dependencies so we do not try to build scripts twice
070b98bf 429# in parallel
4f193362 430PHONY += scripts
2e3646e5 431scripts: scripts_basic include/config/auto.conf
1da177e4
LT
432 $(Q)$(MAKE) $(build)=$(@)
433
1da177e4
LT
434# Objects we will link into vmlinux / subdirs we need to visit
435init-y := init/
436drivers-y := drivers/ sound/
437net-y := net/
438libs-y := lib/
439core-y := usr/
440endif # KBUILD_EXTMOD
441
442ifeq ($(dot-config),1)
9ee4e336
SR
443# Read in config
444-include include/config/auto.conf
1da177e4 445
9ee4e336 446ifeq ($(KBUILD_EXTMOD),)
1da177e4
LT
447# Read in dependencies to all Kconfig* files, make sure to run
448# oldconfig if changes are detected.
c955ccaf 449-include include/config/auto.conf.cmd
1da177e4 450
1da177e4 451# To avoid any implicit rule to kick in, define an empty command
14cdd3c4 452$(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
1da177e4 453
c955ccaf 454# If .config is newer than include/config/auto.conf, someone tinkered
752625cf 455# with it and forgot to run make oldconfig.
070b98bf 456# if auto.conf.cmd is missing then we are probably in a cleaned tree so
752625cf 457# we execute the config step to be sure to catch updated Kconfig files
14cdd3c4 458include/config/auto.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
1da177e4 459 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
3041e47e 460else
9ee4e336
SR
461# external modules needs include/linux/autoconf.h and include/config/auto.conf
462# but do not care if they are up-to-date. Use auto.conf to trigger the test
463PHONY += include/config/auto.conf
464
465include/config/auto.conf:
466 $(Q)test -e include/linux/autoconf.h -a -e $@ || ( \
467 echo; \
468 echo " ERROR: Kernel configuration is invalid."; \
469 echo " include/linux/autoconf.h or $@ are missing."; \
470 echo " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
471 echo; \
472 /bin/false)
473
474endif # KBUILD_EXTMOD
c955ccaf 475
1da177e4
LT
476else
477# Dummy target needed, because used as prerequisite
c955ccaf 478include/config/auto.conf: ;
9ee4e336 479endif # $(dot-config)
1da177e4
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480
481# The all: target is the default when no target is given on the
482# command line.
483# This allow a user to issue only 'make' to build a kernel including modules
070b98bf 484# Defaults vmlinux but it is usually overridden in the arch makefile
1da177e4
LT
485all: vmlinux
486
487ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
488CFLAGS += -Os
489else
490CFLAGS += -O2
491endif
492
c9eca0b9
SR
493include $(srctree)/arch/$(ARCH)/Makefile
494
1da177e4 495ifdef CONFIG_FRAME_POINTER
af332aa3 496CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
1da177e4
LT
497else
498CFLAGS += -fomit-frame-pointer
499endif
500
501ifdef CONFIG_DEBUG_INFO
502CFLAGS += -g
503endif
504
c9eca0b9
SR
505# Force gcc to behave correct even for buggy distributions
506CFLAGS += $(call cc-option, -fno-stack-protector)
1da177e4 507
e8e69931 508# arch Makefile may override CC so keep this after arch Makefile is included
e8f5bdb0 509NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
e8e69931
SR
510CHECKFLAGS += $(NOSTDINC_FLAGS)
511
1da177e4
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512# warn about C99 declaration after statement
513CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
514
070b98bf 515# disable pointer signed / unsigned warnings in gcc 4.0
1da177e4
LT
516CFLAGS += $(call cc-option,-Wno-pointer-sign,)
517
18991197
RM
518# Use --build-id when available.
519LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
520 $(call ld-option, -Wl$(comma)--build-id,))
521LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
522LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
523
1da177e4 524# Default kernel image to build when no specific target is given.
070b98bf 525# KBUILD_IMAGE may be overruled on the command line or
1da177e4
LT
526# set in the environment
527# Also any assignments in arch/$(ARCH)/Makefile take precedence over
528# this default value
529export KBUILD_IMAGE ?= vmlinux
530
531#
532# INSTALL_PATH specifies where to place the updated kernel and system map
533# images. Default is /boot, but you can set it to other values
534export INSTALL_PATH ?= /boot
535
536#
537# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
538# relocations required by build roots. This is not defined in the
070b98bf 539# makefile but the argument can be passed to make if needed.
1da177e4
LT
540#
541
df9df036 542MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1da177e4
LT
543export MODLIB
544
ac031f26
TT
545#
546# INSTALL_MOD_STRIP, if defined, will cause modules to be
547# stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
548# the default option --strip-debug will be used. Otherwise,
549# INSTALL_MOD_STRIP will used as the options to the strip command.
550
551ifdef INSTALL_MOD_STRIP
552ifeq ($(INSTALL_MOD_STRIP),1)
e340221a 553mod_strip_cmd = $(STRIP) --strip-debug
ac031f26
TT
554else
555mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
556endif # INSTALL_MOD_STRIP=1
557else
558mod_strip_cmd = true
559endif # INSTALL_MOD_STRIP
560export mod_strip_cmd
561
1da177e4
LT
562
563ifeq ($(KBUILD_EXTMOD),)
3a65dfe8 564core-y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/
1da177e4
LT
565
566vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
567 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
568 $(net-y) $(net-m) $(libs-y) $(libs-m)))
569
570vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
571 $(init-n) $(init-) \
572 $(core-n) $(core-) $(drivers-n) $(drivers-) \
573 $(net-n) $(net-) $(libs-n) $(libs-))))
574
575init-y := $(patsubst %/, %/built-in.o, $(init-y))
576core-y := $(patsubst %/, %/built-in.o, $(core-y))
577drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
578net-y := $(patsubst %/, %/built-in.o, $(net-y))
579libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
580libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
581libs-y := $(libs-y1) $(libs-y2)
582
583# Build vmlinux
584# ---------------------------------------------------------------------------
070b98bf 585# vmlinux is built from the objects selected by $(vmlinux-init) and
1da177e4 586# $(vmlinux-main). Most are built-in.o files from top-level directories
2462566f 587# in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
1da177e4
LT
588# Ordering when linking is important, and $(vmlinux-init) must be first.
589#
590# vmlinux
591# ^
592# |
593# +-< $(vmlinux-init)
594# | +--< init/version.o + more
595# |
596# +--< $(vmlinux-main)
597# | +--< driver/built-in.o mm/built-in.o + more
598# |
599# +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
600#
601# vmlinux version (uname -v) cannot be updated during normal
602# descending-into-subdirs phase since we do not yet know if we need to
603# update vmlinux.
604# Therefore this step is delayed until just before final link of vmlinux -
605# except in the kallsyms case where it is done just before adding the
606# symbols to the kernel.
607#
608# System.map is generated to document addresses of all kernel symbols
609
610vmlinux-init := $(head-y) $(init-y)
611vmlinux-main := $(core-y) $(libs-y) $(drivers-y) $(net-y)
612vmlinux-all := $(vmlinux-init) $(vmlinux-main)
6752ed90 613vmlinux-lds := arch/$(SRCARCH)/kernel/vmlinux.lds
85bd2fdd 614export KBUILD_VMLINUX_OBJS := $(vmlinux-all)
1da177e4
LT
615
616# Rule to link vmlinux - also used during CONFIG_KALLSYMS
617# May be overridden by arch/$(ARCH)/Makefile
618quiet_cmd_vmlinux__ ?= LD $@
619 cmd_vmlinux__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) -o $@ \
620 -T $(vmlinux-lds) $(vmlinux-init) \
621 --start-group $(vmlinux-main) --end-group \
741f98fe 622 $(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o FORCE ,$^)
1da177e4
LT
623
624# Generate new vmlinux version
625quiet_cmd_vmlinux_version = GEN .version
626 cmd_vmlinux_version = set -e; \
4e25d8bb
JB
627 if [ ! -r .version ]; then \
628 rm -f .version; \
629 echo 1 >.version; \
630 else \
631 mv .version .old_version; \
632 expr 0$$(cat .old_version) + 1 >.version; \
633 fi; \
1da177e4
LT
634 $(MAKE) $(build)=init
635
636# Generate System.map
070b98bf 637quiet_cmd_sysmap = SYSMAP
1da177e4
LT
638 cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap
639
640# Link of vmlinux
641# If CONFIG_KALLSYMS is set .version is already updated
642# Generate System.map and verify that the content is consistent
39ca371c
MR
643# Use + in front of the vmlinux_version rule to silent warning with make -j2
644# First command is ':' to allow us to use + in front of the rule
1da177e4 645define rule_vmlinux__
39ca371c 646 :
1da177e4
LT
647 $(if $(CONFIG_KALLSYMS),,+$(call cmd,vmlinux_version))
648
649 $(call cmd,vmlinux__)
650 $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
651
4635281c
SR
652 $(Q)$(if $($(quiet)cmd_sysmap), \
653 echo ' $($(quiet)cmd_sysmap) System.map' &&) \
654 $(cmd_sysmap) $@ System.map; \
655 if [ $$? -ne 0 ]; then \
656 rm -f $@; \
657 /bin/false; \
1da177e4
LT
658 fi;
659 $(verify_kallsyms)
660endef
661
662
663ifdef CONFIG_KALLSYMS
664# Generate section listing all symbols and add it into vmlinux $(kallsyms.o)
665# It's a three stage process:
666# o .tmp_vmlinux1 has all symbols and sections, but __kallsyms is
667# empty
668# Running kallsyms on that gives us .tmp_kallsyms1.o with
669# the right size - vmlinux version (uname -v) is updated during this step
670# o .tmp_vmlinux2 now has a __kallsyms section of the right size,
671# but due to the added section, some addresses have shifted.
672# From here, we generate a correct .tmp_kallsyms2.o
673# o The correct .tmp_kallsyms2.o is linked into the final vmlinux.
674# o Verify that the System.map from vmlinux matches the map from
675# .tmp_vmlinux2, just in case we did not generate kallsyms correctly.
676# o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
677# .tmp_vmlinux3 and .tmp_kallsyms3.o. This is only meant as a
678# temporary bypass to allow the kernel to be built while the
679# maintainers work out what went wrong with kallsyms.
680
681ifdef CONFIG_KALLSYMS_EXTRA_PASS
682last_kallsyms := 3
683else
684last_kallsyms := 2
685endif
686
687kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
688
689define verify_kallsyms
4635281c
SR
690 $(Q)$(if $($(quiet)cmd_sysmap), \
691 echo ' $($(quiet)cmd_sysmap) .tmp_System.map' &&) \
1da177e4 692 $(cmd_sysmap) .tmp_vmlinux$(last_kallsyms) .tmp_System.map
4635281c
SR
693 $(Q)cmp -s System.map .tmp_System.map || \
694 (echo Inconsistent kallsyms data; \
695 echo Try setting CONFIG_KALLSYMS_EXTRA_PASS; \
1da177e4
LT
696 rm .tmp_kallsyms* ; /bin/false )
697endef
698
699# Update vmlinux version before link
700# Use + in front of this rule to silent warning about make -j1
72ba47c1 701# First command is ':' to allow us to use + in front of this rule
1da177e4
LT
702cmd_ksym_ld = $(cmd_vmlinux__)
703define rule_ksym_ld
72ba47c1 704 :
1da177e4
LT
705 +$(call cmd,vmlinux_version)
706 $(call cmd,vmlinux__)
707 $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
708endef
709
710# Generate .S file with all kernel symbols
711quiet_cmd_kallsyms = KSYM $@
712 cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
713 $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
714
715.tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
716 $(call if_changed_dep,as_o_S)
717
718.tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
719 $(call cmd,kallsyms)
720
721# .tmp_vmlinux1 must be complete except kallsyms, so update vmlinux version
722.tmp_vmlinux1: $(vmlinux-lds) $(vmlinux-all) FORCE
723 $(call if_changed_rule,ksym_ld)
724
725.tmp_vmlinux2: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms1.o FORCE
726 $(call if_changed,vmlinux__)
727
728.tmp_vmlinux3: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms2.o FORCE
729 $(call if_changed,vmlinux__)
730
731# Needs to visit scripts/ before $(KALLSYMS) can be used.
732$(KALLSYMS): scripts ;
733
33bc25ea
SR
734# Generate some data for debugging strange kallsyms problems
735debug_kallsyms: .tmp_map$(last_kallsyms)
736
737.tmp_map%: .tmp_vmlinux% FORCE
738 ($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@
739
740.tmp_map3: .tmp_map2
741
742.tmp_map2: .tmp_map1
743
1da177e4
LT
744endif # ifdef CONFIG_KALLSYMS
745
741f98fe
SR
746# Do modpost on a prelinked vmlinux. The finally linked vmlinux has
747# relevant sections renamed as per the linker script.
748quiet_cmd_vmlinux-modpost = LD $@
749 cmd_vmlinux-modpost = $(LD) $(LDFLAGS) -r -o $@ \
750 $(vmlinux-init) --start-group $(vmlinux-main) --end-group \
751 $(filter-out $(vmlinux-init) $(vmlinux-main) $(vmlinux-lds) FORCE ,$^)
752define rule_vmlinux-modpost
753 :
754 +$(call cmd,vmlinux-modpost)
755 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $@
756 $(Q)echo 'cmd_$@ := $(cmd_vmlinux-modpost)' > $(dot-target).cmd
757endef
758
1da177e4 759# vmlinux image - including updated kernel symbols
741f98fe 760vmlinux: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) $(kallsyms.o) vmlinux.o FORCE
0f836e5f 761ifdef CONFIG_HEADERS_CHECK
0e7af8d0 762 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
0f836e5f 763endif
741f98fe 764 $(call vmlinux-modpost)
1da177e4 765 $(call if_changed_rule,vmlinux__)
4e25d8bb 766 $(Q)rm -f .old_version
1da177e4 767
741f98fe
SR
768vmlinux.o: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) $(kallsyms.o) FORCE
769 $(call if_changed_rule,vmlinux-modpost)
770
1da177e4
LT
771# The actual objects are generated when descending,
772# make sure no implicit rule kicks in
773$(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(vmlinux-dirs) ;
774
775# Handle descending into subdirectories listed in $(vmlinux-dirs)
776# Preset locale variables to speed up the build process. Limit locale
777# tweaks to this spot to avoid wrong language settings when running
778# make menuconfig etc.
779# Error messages still appears in the original language
780
4f193362 781PHONY += $(vmlinux-dirs)
5bb78269 782$(vmlinux-dirs): prepare scripts
1da177e4
LT
783 $(Q)$(MAKE) $(build)=$@
784
cb58455c 785# Build the kernel release string
cb58455c 786#
1ef98856
RD
787# The KERNELRELEASE value built here is stored in the file
788# include/config/kernel.release, and is used when executing several
789# make targets, such as "make install" or "make modules_install."
790#
791# The eventual kernel release string consists of the following fields,
792# shown in a hierarchical format to show how smaller parts are concatenated
793# to form the larger and final value, with values coming from places like
794# the Makefile, kernel config options, make command line options and/or
795# SCM tag information.
796#
797# $(KERNELVERSION)
798# $(VERSION) eg, 2
799# $(PATCHLEVEL) eg, 6
800# $(SUBLEVEL) eg, 18
801# $(EXTRAVERSION) eg, -rc6
802# $(localver-full)
803# $(localver)
76c32956 804# localversion* (files without backups, containing '~')
1ef98856
RD
805# $(CONFIG_LOCALVERSION) (from kernel config setting)
806# $(localver-auto) (only if CONFIG_LOCALVERSION_AUTO is set)
807# ./scripts/setlocalversion (SCM tag, if one exists)
808# $(LOCALVERSION) (from make command line if provided)
809#
810# Note how the final $(localver-auto) string is included *only* if the
811# kernel config option CONFIG_LOCALVERSION_AUTO is selected. Also, at the
812# moment, only git is supported but other SCMs can edit the script
813# scripts/setlocalversion and add the appropriate checks as needed.
cb58455c 814
76c32956
OV
815pattern = ".*/localversion[^~]*"
816string = $(shell cat /dev/null \
fd19e44f 817 `find $(objtree) $(srctree) -maxdepth 1 -regex $(pattern) | sort -u`)
cb58455c 818
76c32956
OV
819localver = $(subst $(space),, $(string) \
820 $(patsubst "%",%,$(CONFIG_LOCALVERSION)))
070b98bf 821
cb58455c
SR
822# If CONFIG_LOCALVERSION_AUTO is set scripts/setlocalversion is called
823# and if the SCM is know a tag from the SCM is appended.
070b98bf 824# The appended tag is determined by the SCM used.
cb58455c
SR
825#
826# Currently, only git is supported.
827# Other SCMs can edit scripts/setlocalversion and add the appropriate
828# checks as needed.
829ifdef CONFIG_LOCALVERSION_AUTO
830 _localver-auto = $(shell $(CONFIG_SHELL) \
831 $(srctree)/scripts/setlocalversion $(srctree))
832 localver-auto = $(LOCALVERSION)$(_localver-auto)
833endif
834
835localver-full = $(localver)$(localver-auto)
836
f1d28fb0 837# Store (new) KERNELRELASE string in include/config/kernel.release
2244cbd8 838kernelrelease = $(KERNELVERSION)$(localver-full)
f1d28fb0 839include/config/kernel.release: include/config/auto.conf FORCE
2244cbd8
SR
840 $(Q)rm -f $@
841 $(Q)echo $(kernelrelease) > $@
cb58455c
SR
842
843
1da177e4 844# Things we need to do before we recursively start building the kernel
5bb78269
SR
845# or the modules are listed in "prepare".
846# A multi level approach is used. prepareN is processed before prepareN-1.
847# archprepare is used in arch Makefiles and when processed asm symlink,
848# version.h and scripts_basic is processed / created.
1da177e4 849
5bb78269 850# Listed in dependency order
4f193362 851PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
5bb78269 852
86feeaa8 853# prepare3 is used to check if we are building in a separate output directory,
1da177e4
LT
854# and if so do:
855# 1) Check that make has not been executed in the kernel src $(srctree)
856# 2) Create the include2 directory, used for the second asm symlink
f1d28fb0 857prepare3: include/config/kernel.release
1da177e4
LT
858ifneq ($(KBUILD_SRC),)
859 @echo ' Using $(srctree) as source for kernel'
c955ccaf 860 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1da177e4
LT
861 echo " $(srctree) is not clean, please run 'make mrproper'";\
862 echo " in the '$(srctree)' directory.";\
863 /bin/false; \
864 fi;
865 $(Q)if [ ! -d include2 ]; then mkdir -p include2; fi;
96a388de 866 $(Q)ln -fsn $(srctree)/include/asm-$(SRCARCH) include2/asm
1da177e4
LT
867endif
868
86feeaa8
SR
869# prepare2 creates a makefile if using a separate output directory
870prepare2: prepare3 outputmakefile
1da177e4 871
3eb3c740
RZ
872prepare1: prepare2 include/linux/version.h include/linux/utsrelease.h \
873 include/asm include/config/auto.conf
1da177e4 874ifneq ($(KBUILD_MODULES),)
1da177e4 875 $(Q)mkdir -p $(MODVERDIR)
fca1dff2 876 $(Q)rm -f $(MODVERDIR)/*
1da177e4
LT
877endif
878
5bb78269
SR
879archprepare: prepare1 scripts_basic
880
881prepare0: archprepare FORCE
8d36a623 882 $(Q)$(MAKE) $(build)=.
c53aeca0 883 $(Q)$(MAKE) $(build)=. missing-syscalls
86feeaa8 884
1da177e4 885# All the preparing..
d395efb5 886prepare: prepare0
1da177e4 887
070b98bf
SR
888# Leave this as default for preprocessing vmlinux.lds.S, which is now
889# done in arch/$(ARCH)/kernel/Makefile
1da177e4
LT
890
891export CPPFLAGS_vmlinux.lds += -P -C -U$(ARCH)
892
070b98bf
SR
893# FIXME: The asm symlink changes when $(ARCH) changes. That's
894# hard to detect, but I suppose "make mrproper" is a good idea
895# before switching between archs anyway.
1da177e4
LT
896
897include/asm:
96a388de 898 @echo ' SYMLINK $@ -> include/asm-$(SRCARCH)'
1da177e4 899 $(Q)if [ ! -d include ]; then mkdir -p include; fi;
96a388de 900 @ln -fsn asm-$(SRCARCH) $@
1da177e4 901
1da177e4
LT
902# Generate some files
903# ---------------------------------------------------------------------------
904
905# KERNELRELEASE can change from a few different places, meaning version.h
906# needs to be updated, so this check is forced on all builds
907
908uts_len := 64
63104eec
SR
909define filechk_utsrelease.h
910 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
911 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
912 exit 1; \
913 fi; \
914 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
915endef
1da177e4
LT
916
917define filechk_version.h
63104eec
SR
918 (echo \#define LINUX_VERSION_CODE $(shell \
919 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
920 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1da177e4
LT
921endef
922
63104eec 923include/linux/version.h: $(srctree)/Makefile FORCE
1da177e4
LT
924 $(call filechk,version.h)
925
63104eec
SR
926include/linux/utsrelease.h: include/config/kernel.release FORCE
927 $(call filechk,utsrelease.h)
928
1da177e4
LT
929# ---------------------------------------------------------------------------
930
4f193362 931PHONY += depend dep
1da177e4
LT
932depend dep:
933 @echo '*** Warning: make $@ is unnecessary now.'
934
8d730cfb
DW
935# ---------------------------------------------------------------------------
936# Kernel headers
1ab7a1f3 937INSTALL_HDR_PATH=$(objtree)/usr
8d730cfb
DW
938export INSTALL_HDR_PATH
939
96a388de
TG
940HDRFILTER=generic i386 x86_64
941HDRARCHES=$(filter-out $(HDRFILTER),$(patsubst $(srctree)/include/asm-%/Kbuild,%,$(wildcard $(srctree)/include/asm-*/Kbuild)))
6d716275
DW
942
943PHONY += headers_install_all
3eb3c740 944headers_install_all: include/linux/version.h scripts_basic FORCE
398477d4 945 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
6d716275 946 $(Q)for arch in $(HDRARCHES); do \
398477d4 947 $(MAKE) ARCH=$$arch -f $(srctree)/scripts/Makefile.headersinst obj=include BIASMDIR=-bi-$$arch ;\
6d716275
DW
948 done
949
8d730cfb 950PHONY += headers_install
3eb3c740 951headers_install: include/linux/version.h scripts_basic FORCE
96a388de
TG
952 @if [ ! -r $(srctree)/include/asm-$(SRCARCH)/Kbuild ]; then \
953 echo '*** Error: Headers not exportable for this architecture ($(SRCARCH))'; \
f17b7bad 954 exit 1 ; fi
07aea3a7 955 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
96a388de 956 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.headersinst ARCH=$(SRCARCH) obj=include
8d730cfb 957
1f85712e
MF
958PHONY += headers_check_all
959headers_check_all: headers_install_all
960 $(Q)for arch in $(HDRARCHES); do \
961 $(MAKE) ARCH=$$arch -f $(srctree)/scripts/Makefile.headersinst obj=include BIASMDIR=-bi-$$arch HDRCHECK=1 ;\
962 done
963
68475359
DW
964PHONY += headers_check
965headers_check: headers_install
96a388de 966 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.headersinst ARCH=$(SRCARCH) obj=include HDRCHECK=1
68475359 967
1da177e4
LT
968# ---------------------------------------------------------------------------
969# Modules
970
971ifdef CONFIG_MODULES
972
070b98bf 973# By default, build modules as well
1da177e4
LT
974
975all: modules
976
977# Build modules
978
4f193362 979PHONY += modules
1da177e4
LT
980modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux)
981 @echo ' Building modules, stage 2.';
b805aa0e 982 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1da177e4
LT
983
984
985# Target to prepare building external modules
4f193362 986PHONY += modules_prepare
5bb78269 987modules_prepare: prepare scripts
1da177e4
LT
988
989# Target to install modules
4f193362 990PHONY += modules_install
1da177e4
LT
991modules_install: _modinst_ _modinst_post
992
4f193362 993PHONY += _modinst_
1da177e4 994_modinst_:
ce454d4d 995 @if [ -z "`$(DEPMOD) -V 2>/dev/null | grep module-init-tools`" ]; then \
1da177e4
LT
996 echo "Warning: you may need to install module-init-tools"; \
997 echo "See http://www.codemonkey.org.uk/docs/post-halloween-2.6.txt";\
998 sleep 1; \
999 fi
1000 @rm -rf $(MODLIB)/kernel
1001 @rm -f $(MODLIB)/source
1002 @mkdir -p $(MODLIB)/kernel
1003 @ln -s $(srctree) $(MODLIB)/source
1004 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1005 rm -f $(MODLIB)/build ; \
1006 ln -s $(objtree) $(MODLIB)/build ; \
1007 fi
b805aa0e 1008 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1da177e4
LT
1009
1010# If System.map exists, run depmod. This deliberately does not have a
1011# dependency on System.map since that would run the dependency tree on
1012# vmlinux. This depmod is only for convenience to give the initial
1013# boot a modules.dep even before / is mounted read-write. However the
1014# boot script depmod is the master version.
1015ifeq "$(strip $(INSTALL_MOD_PATH))" ""
1016depmod_opts :=
1017else
1018depmod_opts := -b $(INSTALL_MOD_PATH) -r
1019endif
4f193362 1020PHONY += _modinst_post
1da177e4
LT
1021_modinst_post: _modinst_
1022 if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
1023
1024else # CONFIG_MODULES
1025
1026# Modules not configured
1027# ---------------------------------------------------------------------------
1028
1029modules modules_install: FORCE
1030 @echo
1031 @echo "The present kernel configuration has modules disabled."
1032 @echo "Type 'make config' and enable loadable module support."
1033 @echo "Then build a kernel with module support enabled."
1034 @echo
1035 @exit 1
1036
1037endif # CONFIG_MODULES
1038
1da177e4
LT
1039###
1040# Cleaning is done on three levels.
1041# make clean Delete most generated files
1042# Leave enough to build external modules
1043# make mrproper Delete the current configuration, and all generated files
1044# make distclean Remove editor backup files, patch leftover files and the like
1045
1046# Directories & files removed with 'make clean'
1047CLEAN_DIRS += $(MODVERDIR)
1048CLEAN_FILES += vmlinux System.map \
1049 .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map
1050
1051# Directories & files removed with 'make mrproper'
1ab7a1f3 1052MRPROPER_DIRS += include/config include2 usr/include
50aa88e2 1053MRPROPER_FILES += .config .config.old include/asm .version .old_version \
3eb3c740
RZ
1054 include/linux/autoconf.h include/linux/version.h \
1055 include/linux/utsrelease.h \
f1d28fb0 1056 Module.symvers tags TAGS cscope*
1da177e4
LT
1057
1058# clean - Delete most, but leave enough to build external modules
1059#
1060clean: rm-dirs := $(CLEAN_DIRS)
1061clean: rm-files := $(CLEAN_FILES)
86feeaa8 1062clean-dirs := $(addprefix _clean_,$(srctree) $(vmlinux-alldirs))
1da177e4 1063
4f193362 1064PHONY += $(clean-dirs) clean archclean
1da177e4
LT
1065$(clean-dirs):
1066 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1067
1068clean: archclean $(clean-dirs)
1069 $(call cmd,rmdirs)
1070 $(call cmd,rmfiles)
1071 @find . $(RCS_FIND_IGNORE) \
070b98bf 1072 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
15fde675
AG
1073 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1074 -o -name '*.symtypes' \) \
1da177e4
LT
1075 -type f -print | xargs rm -f
1076
1077# mrproper - Delete all generated files, including .config
1078#
1079mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1080mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1081mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1082
4f193362 1083PHONY += $(mrproper-dirs) mrproper archmrproper
1da177e4
LT
1084$(mrproper-dirs):
1085 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1086
1087mrproper: clean archmrproper $(mrproper-dirs)
1088 $(call cmd,rmdirs)
1089 $(call cmd,rmfiles)
1090
1091# distclean
1092#
4f193362 1093PHONY += distclean
1da177e4
LT
1094
1095distclean: mrproper
1096 @find $(srctree) $(RCS_FIND_IGNORE) \
070b98bf 1097 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1da177e4 1098 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
070b98bf 1099 -o -name '.*.rej' -o -size 0 \
1da177e4
LT
1100 -o -name '*%' -o -name '.*.cmd' -o -name 'core' \) \
1101 -type f -print | xargs rm -f
1102
1103
1104# Packaging of the kernel to various formats
1105# ---------------------------------------------------------------------------
1106# rpm target kept for backward compatibility
1107package-dir := $(srctree)/scripts/package
1108
031ecc6d 1109%pkg: include/config/kernel.release FORCE
6c2133e1 1110 $(Q)$(MAKE) $(build)=$(package-dir) $@
031ecc6d 1111rpm: include/config/kernel.release FORCE
6c2133e1 1112 $(Q)$(MAKE) $(build)=$(package-dir) $@
1da177e4
LT
1113
1114
1115# Brief documentation of the typical targets used
1116# ---------------------------------------------------------------------------
1117
1118boards := $(wildcard $(srctree)/arch/$(ARCH)/configs/*_defconfig)
1119boards := $(notdir $(boards))
1120
1121help:
1122 @echo 'Cleaning targets:'
5ea084ef 1123 @echo ' clean - Remove most generated files but keep the config and'
5cc8d246 1124 @echo ' enough build support to build external modules'
5ea084ef 1125 @echo ' mrproper - Remove all generated files + config + various backup files'
5cc8d246 1126 @echo ' distclean - mrproper + remove editor backup and patch files'
1da177e4
LT
1127 @echo ''
1128 @echo 'Configuration targets:'
1129 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1130 @echo ''
1131 @echo 'Other generic targets:'
1132 @echo ' all - Build all targets marked with [*]'
1133 @echo '* vmlinux - Build the bare kernel'
1134 @echo '* modules - Build all modules'
9cc5d74c 1135 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1da177e4
LT
1136 @echo ' dir/ - Build all files in dir and below'
1137 @echo ' dir/file.[ois] - Build specified target only'
155ad605 1138 @echo ' dir/file.ko - Build module including final link'
1da177e4
LT
1139 @echo ' rpm - Build a kernel as an RPM package'
1140 @echo ' tags/TAGS - Generate tags file for editors'
1141 @echo ' cscope - Generate cscope index'
6d128842 1142 @echo ' kernelrelease - Output the release version string'
cb58455c 1143 @echo ' kernelversion - Output the version stored in Makefile'
91e034ef 1144 @if [ -r $(srctree)/include/asm-$(SRCARCH)/Kbuild ]; then \
f17b7bad 1145 echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
59df3230 1146 echo ' (default: $(INSTALL_HDR_PATH))'; \
f17b7bad 1147 fi
1da177e4
LT
1148 @echo ''
1149 @echo 'Static analysers'
1da177e4
LT
1150 @echo ' checkstack - Generate a list of stack hogs'
1151 @echo ' namespacecheck - Name space analysis on compiled kernel'
91e034ef 1152 @if [ -r $(srctree)/include/asm-$(SRCARCH)/Kbuild ]; then \
f17b7bad
DW
1153 echo ' headers_check - Sanity check on exported headers'; \
1154 fi
1da177e4
LT
1155 @echo ''
1156 @echo 'Kernel packaging:'
6c2133e1 1157 @$(MAKE) $(build)=$(package-dir) help
1da177e4
LT
1158 @echo ''
1159 @echo 'Documentation targets:'
1160 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1161 @echo ''
1162 @echo 'Architecture specific targets ($(ARCH)):'
1163 @$(if $(archhelp),$(archhelp),\
1164 echo ' No architecture specific help defined for $(ARCH)')
1165 @echo ''
1166 @$(if $(boards), \
1167 $(foreach b, $(boards), \
1168 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1169 echo '')
1170
1171 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
45d506bd 1172 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1da177e4 1173 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
701842e3
DK
1174 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1175 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1da177e4
LT
1176 @echo ''
1177 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1178 @echo 'For further info see the ./README file'
1179
1180
1181# Documentation targets
1182# ---------------------------------------------------------------------------
1183%docs: scripts_basic FORCE
1184 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1185
1186else # KBUILD_EXTMOD
1187
1188###
1189# External module support.
1190# When building external modules the kernel used as basis is considered
1191# read-only, and no consistency checks are made and the make
1192# system is not used on the basis kernel. If updates are required
1193# in the basis kernel ordinary make commands (without M=...) must
1194# be used.
1195#
1196# The following are the only valid targets when building external
1197# modules.
1198# make M=dir clean Delete all automatically generated files
1199# make M=dir modules Make all modules in specified dir
1200# make M=dir Same as 'make M=dir modules'
1201# make M=dir modules_install
070b98bf 1202# Install the modules built in the module directory
1da177e4
LT
1203# Assumes install directory is already created
1204
1205# We are always building modules
1206KBUILD_MODULES := 1
4f193362 1207PHONY += crmodverdir
1da177e4
LT
1208crmodverdir:
1209 $(Q)mkdir -p $(MODVERDIR)
fca1dff2 1210 $(Q)rm -f $(MODVERDIR)/*
1da177e4 1211
4f193362 1212PHONY += $(objtree)/Module.symvers
1da177e4
LT
1213$(objtree)/Module.symvers:
1214 @test -e $(objtree)/Module.symvers || ( \
1215 echo; \
1216 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1217 echo " is missing; modules will have no dependencies and modversions."; \
1218 echo )
1219
1220module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
4f193362 1221PHONY += $(module-dirs) modules
1da177e4
LT
1222$(module-dirs): crmodverdir $(objtree)/Module.symvers
1223 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1224
1225modules: $(module-dirs)
1226 @echo ' Building modules, stage 2.';
b805aa0e 1227 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1da177e4 1228
4f193362 1229PHONY += modules_install
a67dc21a 1230modules_install: _emodinst_ _emodinst_post
e6304663 1231
4f193362
PS
1232install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1233PHONY += _emodinst_
a67dc21a 1234_emodinst_:
a67dc21a 1235 $(Q)mkdir -p $(MODLIB)/$(install-dir)
b805aa0e 1236 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1da177e4 1237
a67dc21a
SR
1238# Run depmod only is we have System.map and depmod is executable
1239quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1240 cmd_depmod = if [ -r System.map -a -x $(DEPMOD) ]; then \
1241 $(DEPMOD) -ae -F System.map \
1242 $(if $(strip $(INSTALL_MOD_PATH)), \
1243 -b $(INSTALL_MOD_PATH) -r) \
1244 $(KERNELRELEASE); \
1245 fi
1246
4f193362 1247PHONY += _emodinst_post
a67dc21a
SR
1248_emodinst_post: _emodinst_
1249 $(call cmd,depmod)
1250
1da177e4
LT
1251clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1252
4f193362 1253PHONY += $(clean-dirs) clean
1da177e4
LT
1254$(clean-dirs):
1255 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1256
1257clean: rm-dirs := $(MODVERDIR)
1258clean: $(clean-dirs)
1259 $(call cmd,rmdirs)
1260 @find $(KBUILD_EXTMOD) $(RCS_FIND_IGNORE) \
070b98bf 1261 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1da177e4
LT
1262 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
1263 -type f -print | xargs rm -f
1264
1265help:
1266 @echo ' Building external modules.'
1267 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1268 @echo ''
1269 @echo ' modules - default target, build the module(s)'
1270 @echo ' modules_install - install the module'
1271 @echo ' clean - remove generated files in module directory only'
1272 @echo ''
06300b21
SR
1273
1274# Dummies...
4f193362 1275PHONY += prepare scripts
06300b21
SR
1276prepare: ;
1277scripts: ;
1da177e4
LT
1278endif # KBUILD_EXTMOD
1279
1280# Generate tags for editors
1281# ---------------------------------------------------------------------------
1282
1283#We want __srctree to totally vanish out when KBUILD_OUTPUT is not set
1284#(which is the most common case IMHO) to avoid unneeded clutter in the big tags file.
1285#Adding $(srctree) adds about 20M on i386 to the size of the output file!
1286
f182ae62 1287ifeq ($(src),$(obj))
1da177e4
LT
1288__srctree =
1289else
1290__srctree = $(srctree)/
1291endif
1292
2ab23c95
PBG
1293ifeq ($(ALLSOURCE_ARCHS),)
1294ifeq ($(ARCH),um)
1295ALLINCLUDE_ARCHS := $(ARCH) $(SUBARCH)
1296else
2eb4c950 1297ALLINCLUDE_ARCHS := $(SRCARCH)
2ab23c95
PBG
1298endif
1299else
070b98bf 1300#Allow user to specify only ALLSOURCE_PATHS on the command line, keeping existing behavour.
2ab23c95
PBG
1301ALLINCLUDE_ARCHS := $(ALLSOURCE_ARCHS)
1302endif
1303
2eb4c950
TG
1304# Take care of arch/x86
1305ifeq ($(ARCH), $(SRCARCH))
a0674e88 1306ALLSOURCE_ARCHS := $(ARCH)
2eb4c950
TG
1307else
1308ALLSOURCE_ARCHS := $(ARCH) $(SRCARCH)
1309endif
a0674e88 1310
e838db68 1311define find-sources
dd7e54ad 1312 ( for ARCH in $(ALLSOURCE_ARCHS) ; do \
2eb4c950 1313 find $(__srctree)arch/$${SRCARCH} $(RCS_FIND_IGNORE) \
e838db68 1314 -name $1 -print; \
a0674e88 1315 done ; \
1da177e4 1316 find $(__srctree)security/selinux/include $(RCS_FIND_IGNORE) \
e838db68 1317 -name $1 -print; \
1da177e4
LT
1318 find $(__srctree)include $(RCS_FIND_IGNORE) \
1319 \( -name config -o -name 'asm-*' \) -prune \
e838db68 1320 -o -name $1 -print; \
2ab23c95 1321 for ARCH in $(ALLINCLUDE_ARCHS) ; do \
2eb4c950 1322 find $(__srctree)include/asm-$${SRCARCH} $(RCS_FIND_IGNORE) \
e838db68 1323 -name $1 -print; \
a0674e88 1324 done ; \
1da177e4 1325 find $(__srctree)include/asm-generic $(RCS_FIND_IGNORE) \
dd7e54ad
DM
1326 -name $1 -print; \
1327 find $(__srctree) $(RCS_FIND_IGNORE) \
1328 \( -name include -o -name arch \) -prune -o \
1329 -name $1 -print; \
1330 )
e838db68
MY
1331endef
1332
1333define all-sources
1334 $(call find-sources,'*.[chS]')
1335endef
1336define all-kconfigs
1337 $(call find-sources,'Kconfig*')
1338endef
1339define all-defconfigs
1340 $(call find-sources,'defconfig')
1da177e4
LT
1341endef
1342
da7c0408
AG
1343define xtags
1344 if $1 --version 2>&1 | grep -iq exuberant; then \
1345 $(all-sources) | xargs $1 -a \
1346 -I __initdata,__exitdata,__acquires,__releases \
1347 -I EXPORT_SYMBOL,EXPORT_SYMBOL_GPL \
91b943ee 1348 --extra=+f --c-kinds=+px \
a412c172 1349 --regex-asm='/^ENTRY\(([^)]*)\).*/\1/'; \
da7c0408
AG
1350 $(all-kconfigs) | xargs $1 -a \
1351 --langdef=kconfig \
1352 --language-force=kconfig \
1353 --regex-kconfig='/^[[:blank:]]*config[[:blank:]]+([[:alnum:]_]+)/\1/'; \
18e39913 1354 $(all-defconfigs) | xargs -r $1 -a \
da7c0408
AG
1355 --langdef=dotconfig \
1356 --language-force=dotconfig \
1357 --regex-dotconfig='/^#?[[:blank:]]*(CONFIG_[[:alnum:]_]+)/\1/'; \
1358 elif $1 --version 2>&1 | grep -iq emacs; then \
1359 $(all-sources) | xargs $1 -a; \
1360 $(all-kconfigs) | xargs $1 -a \
1361 --regex='/^[ \t]*config[ \t]+\([a-zA-Z0-9_]+\)/\1/'; \
18e39913 1362 $(all-defconfigs) | xargs -r $1 -a \
da7c0408
AG
1363 --regex='/^#?[ \t]?\(CONFIG_[a-zA-Z0-9_]+\)/\1/'; \
1364 else \
1365 $(all-sources) | xargs $1 -a; \
1366 fi
1367endef
1368
1da177e4 1369quiet_cmd_cscope-file = FILELST cscope.files
acbef459 1370 cmd_cscope-file = (echo \-k; echo \-q; $(all-sources)) > cscope.files
1da177e4
LT
1371
1372quiet_cmd_cscope = MAKE cscope.out
acbef459 1373 cmd_cscope = cscope -b
1da177e4
LT
1374
1375cscope: FORCE
1376 $(call cmd,cscope-file)
1377 $(call cmd,cscope)
1378
1379quiet_cmd_TAGS = MAKE $@
66d609ec
SR
1380define cmd_TAGS
1381 rm -f $@; \
da7c0408 1382 $(call xtags,etags)
66d609ec
SR
1383endef
1384
1385TAGS: FORCE
1386 $(call cmd,TAGS)
1da177e4 1387
1da177e4
LT
1388quiet_cmd_tags = MAKE $@
1389define cmd_tags
1390 rm -f $@; \
da7c0408 1391 $(call xtags,ctags)
1da177e4
LT
1392endef
1393
1da177e4
LT
1394tags: FORCE
1395 $(call cmd,tags)
1396
1397
1398# Scripts to check various things for consistency
1399# ---------------------------------------------------------------------------
1400
1da177e4
LT
1401includecheck:
1402 find * $(RCS_FIND_IGNORE) \
1403 -name '*.[hcS]' -type f -print | sort \
1404 | xargs $(PERL) -w scripts/checkincludes.pl
1405
1406versioncheck:
1407 find * $(RCS_FIND_IGNORE) \
1408 -name '*.[hcS]' -type f -print | sort \
1409 | xargs $(PERL) -w scripts/checkversion.pl
1410
1da177e4
LT
1411namespacecheck:
1412 $(PERL) $(srctree)/scripts/namespace.pl
1413
1414endif #ifeq ($(config-targets),1)
1415endif #ifeq ($(mixed-targets),1)
1416
c30a02e0 1417PHONY += checkstack kernelrelease kernelversion
e3ccf6e3 1418
011e3a9a
JD
1419# UML needs a little special treatment here. It wants to use the host
1420# toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1421# else wants $(ARCH), including people doing cross-builds, which means
1422# that $(SUBARCH) doesn't work here.
1423ifeq ($(ARCH), um)
1424CHECKSTACK_ARCH := $(SUBARCH)
1425else
1426CHECKSTACK_ARCH := $(ARCH)
1427endif
1da177e4
LT
1428checkstack:
1429 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
011e3a9a 1430 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1da177e4
LT
1431
1432kernelrelease:
f1d28fb0
RZ
1433 $(if $(wildcard include/config/kernel.release), $(Q)echo $(KERNELRELEASE), \
1434 $(error kernelrelease not valid - run 'make prepare' to update it))
cb58455c 1435kernelversion:
2244cbd8 1436 @echo $(KERNELVERSION)
1da177e4 1437
06300b21
SR
1438# Single targets
1439# ---------------------------------------------------------------------------
bc2546a6
SR
1440# Single targets are compatible with:
1441# - build whith mixed source and output
1442# - build with separate output dir 'make O=...'
1443# - external modules
1444#
1445# target-dir => where to store outputfile
1446# build-dir => directory in kernel source tree to use
1447
1448ifeq ($(KBUILD_EXTMOD),)
aa360879 1449 build-dir = $(patsubst %/,%,$(dir $@))
bc2546a6
SR
1450 target-dir = $(dir $@)
1451else
1452 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1453 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1454 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1455endif
1456
f6ecebd6 1457%.s: %.c prepare scripts FORCE
bc2546a6 1458 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
f6ecebd6 1459%.i: %.c prepare scripts FORCE
bc2546a6 1460 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
f6ecebd6 1461%.o: %.c prepare scripts FORCE
bc2546a6 1462 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
f6ecebd6 1463%.lst: %.c prepare scripts FORCE
bc2546a6 1464 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
f6ecebd6 1465%.s: %.S prepare scripts FORCE
bc2546a6 1466 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
f6ecebd6 1467%.o: %.S prepare scripts FORCE
bc2546a6 1468 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
15fde675
AG
1469%.symtypes: %.c prepare scripts FORCE
1470 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
06300b21 1471
bc2546a6
SR
1472# Modules
1473/ %/: prepare scripts FORCE
06300b21 1474 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
bc2546a6
SR
1475 $(build)=$(build-dir)
1476%.ko: prepare scripts FORCE
06300b21 1477 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
bc2546a6 1478 $(build)=$(build-dir) $(@:.ko=.o)
b805aa0e 1479 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
06300b21 1480
1da177e4
LT
1481# FIXME Should go into a make.lib or something
1482# ===========================================================================
1483
1484quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1485 cmd_rmdirs = rm -rf $(rm-dirs)
1486
1487quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1488 cmd_rmfiles = rm -f $(rm-files)
1489
1490
1491a_flags = -Wp,-MD,$(depfile) $(AFLAGS) $(AFLAGS_KERNEL) \
1492 $(NOSTDINC_FLAGS) $(CPPFLAGS) \
5e8d780d 1493 $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(basetarget).o)
1da177e4
LT
1494
1495quiet_cmd_as_o_S = AS $@
1496cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
1497
1498# read all saved command lines
1499
1500targets := $(wildcard $(sort $(targets)))
1501cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1502
1503ifneq ($(cmd_files),)
1504 $(cmd_files): ; # Do not try to update included dependency files
1505 include $(cmd_files)
1506endif
1507
1da177e4
LT
1508# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir
1509# Usage:
1510# $(Q)$(MAKE) $(clean)=dir
1511clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
1512
1da177e4
LT
1513endif # skip-makefile
1514
4f193362 1515PHONY += FORCE
1da177e4 1516FORCE:
4f193362 1517
15964864
OV
1518# Cancel implicit rules on top Makefile, `-rR' will apply to sub-makes.
1519Makefile: ;
4f193362
PS
1520
1521# Declare the contents of the .PHONY variable as phony. We keep that
1522# information in a variable se we can use it in if_changed and friends.
1523.PHONY: $(PHONY)