xref: /linux/scripts/Makefile.lib (revision 8137a49e1567726eb10fcf55ad141ac19804ca6b)
1# SPDX-License-Identifier: GPL-2.0
2# Backward compatibility
3asflags-y  += $(EXTRA_AFLAGS)
4ccflags-y  += $(EXTRA_CFLAGS)
5cppflags-y += $(EXTRA_CPPFLAGS)
6ldflags-y  += $(EXTRA_LDFLAGS)
7
8# flags that take effect in current and sub directories
9KBUILD_AFLAGS += $(subdir-asflags-y)
10KBUILD_CFLAGS += $(subdir-ccflags-y)
11
12# Figure out what we need to build from the various variables
13# ===========================================================================
14
15# When an object is listed to be built compiled-in and modular,
16# only build the compiled-in version
17obj-m := $(filter-out $(obj-y),$(obj-m))
18
19# Libraries are always collected in one lib file.
20# Filter out objects already built-in
21lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
22
23# Subdirectories we need to descend into
24subdir-ym := $(sort $(subdir-y) $(subdir-m) \
25			$(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m))))
26
27# Handle objects in subdirs:
28# - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and
29#   foo/modules.order
30# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order
31#
32# Generate modules.order to determine modorder. Unfortunately, we don't have
33# information about ordering between -y and -m subdirs. Just put -y's first.
34
35ifdef need-modorder
36obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m))
37else
38obj-m := $(filter-out %/, $(obj-m))
39endif
40
41ifdef need-builtin
42obj-y		:= $(patsubst %/, %/built-in.a, $(obj-y))
43else
44obj-y		:= $(filter-out %/, $(obj-y))
45endif
46
47# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
48suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s))))
49# List composite targets that are constructed by combining other targets
50multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m)))
51# List primitive targets that are compiled from source files
52real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m))
53
54# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
55multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y)
56multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m)
57multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
58
59# Replace multi-part objects by their individual parts,
60# including built-in.a from subdirectories
61real-obj-y := $(call real-search, $(obj-y), .o, -objs -y)
62real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m)
63
64always-y += $(always-m)
65
66# hostprogs-always-y += foo
67# ... is a shorthand for
68# hostprogs += foo
69# always-y  += foo
70hostprogs += $(hostprogs-always-y) $(hostprogs-always-m)
71always-y += $(hostprogs-always-y) $(hostprogs-always-m)
72
73# userprogs-always-y is likewise.
74userprogs += $(userprogs-always-y) $(userprogs-always-m)
75always-y += $(userprogs-always-y) $(userprogs-always-m)
76
77# DTB
78# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
79dtb-$(CONFIG_OF_ALL_DTBS)       += $(dtb-)
80
81# Composite DTB (i.e. DTB constructed by overlay)
82multi-dtb-y := $(call multi-search, $(dtb-y), .dtb, -dtbs)
83# Primitive DTB compiled from *.dts
84real-dtb-y := $(call real-search, $(dtb-y), .dtb, -dtbs)
85# Base DTB that overlay is applied onto (each first word of $(*-dtbs) expansion)
86base-dtb-y := $(foreach m, $(multi-dtb-y), $(firstword $(call suffix-search, $m, .dtb, -dtbs)))
87
88always-y			+= $(dtb-y)
89
90ifneq ($(CHECK_DTBS),)
91always-y += $(patsubst %.dtb,%.dt.yaml, $(real-dtb-y))
92always-y += $(patsubst %.dtbo,%.dt.yaml, $(real-dtb-y))
93endif
94
95# Add subdir path
96
97extra-y		:= $(addprefix $(obj)/,$(extra-y))
98always-y	:= $(addprefix $(obj)/,$(always-y))
99targets		:= $(addprefix $(obj)/,$(targets))
100obj-m		:= $(addprefix $(obj)/,$(obj-m))
101lib-y		:= $(addprefix $(obj)/,$(lib-y))
102real-obj-y	:= $(addprefix $(obj)/,$(real-obj-y))
103real-obj-m	:= $(addprefix $(obj)/,$(real-obj-m))
104multi-obj-m	:= $(addprefix $(obj)/, $(multi-obj-m))
105multi-dtb-y	:= $(addprefix $(obj)/, $(multi-dtb-y))
106real-dtb-y	:= $(addprefix $(obj)/, $(real-dtb-y))
107subdir-ym	:= $(addprefix $(obj)/,$(subdir-ym))
108
109# Finds the multi-part object the current object will be linked into.
110# If the object belongs to two or more multi-part objects, list them all.
111modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
112		$(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=))))
113
114__modname = $(if $(modname-multi),$(modname-multi),$(basetarget))
115
116modname = $(subst $(space),:,$(__modname))
117modfile = $(addprefix $(obj)/,$(__modname))
118
119# target with $(obj)/ and its suffix stripped
120target-stem = $(basename $(patsubst $(obj)/%,%,$@))
121
122# These flags are needed for modversions and compiling, so we define them here
123# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
124# end up in (or would, if it gets compiled in)
125name-fix-token = $(subst $(comma),_,$(subst -,_,$1))
126name-fix = $(call stringify,$(call name-fix-token,$1))
127basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
128modname_flags  = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \
129		 -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname))
130modfile_flags  = -DKBUILD_MODFILE=$(call stringify,$(modfile))
131
132_c_flags       = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
133                     $(filter-out $(ccflags-remove-y), \
134                         $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
135                     $(CFLAGS_$(target-stem).o))
136_a_flags       = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
137                     $(filter-out $(asflags-remove-y), \
138                         $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
139                     $(AFLAGS_$(target-stem).o))
140_cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
141
142#
143# Enable gcov profiling flags for a file, directory or for all files depending
144# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
145# (in this order)
146#
147ifeq ($(CONFIG_GCOV_KERNEL),y)
148_c_flags += $(if $(patsubst n%,, \
149		$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
150		$(CFLAGS_GCOV))
151endif
152
153#
154# Enable address sanitizer flags for kernel except some files or directories
155# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
156#
157ifeq ($(CONFIG_KASAN),y)
158ifneq ($(CONFIG_KASAN_HW_TAGS),y)
159_c_flags += $(if $(patsubst n%,, \
160		$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
161		$(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
162endif
163endif
164
165ifeq ($(CONFIG_UBSAN),y)
166_c_flags += $(if $(patsubst n%,, \
167		$(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
168		$(CFLAGS_UBSAN))
169endif
170
171ifeq ($(CONFIG_KCOV),y)
172_c_flags += $(if $(patsubst n%,, \
173	$(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
174	$(CFLAGS_KCOV))
175endif
176
177#
178# Enable KCSAN flags except some files or directories we don't want to check
179# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
180#
181ifeq ($(CONFIG_KCSAN),y)
182_c_flags += $(if $(patsubst n%,, \
183	$(KCSAN_SANITIZE_$(basetarget).o)$(KCSAN_SANITIZE)y), \
184	$(CFLAGS_KCSAN))
185endif
186
187# $(srctree)/$(src) for including checkin headers from generated source files
188# $(objtree)/$(obj) for including generated headers from checkin source files
189ifeq ($(KBUILD_EXTMOD),)
190ifdef building_out_of_srctree
191_c_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
192_a_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
193_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
194endif
195endif
196
197part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
198quiet_modtag = $(if $(part-of-module),[M],   )
199
200modkern_cflags =                                          \
201	$(if $(part-of-module),                           \
202		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
203		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
204
205modkern_aflags = $(if $(part-of-module),				\
206			$(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE),	\
207			$(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))
208
209c_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
210		 -include $(srctree)/include/linux/compiler_types.h       \
211		 $(_c_flags) $(modkern_cflags)                           \
212		 $(basename_flags) $(modname_flags)
213
214a_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
215		 $(_a_flags) $(modkern_aflags)
216
217cpp_flags      = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
218		 $(_cpp_flags)
219
220ld_flags       = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
221
222DTC_INCLUDE    := $(srctree)/scripts/dtc/include-prefixes
223
224dtc_cpp_flags  = -Wp,-MMD,$(depfile).pre.tmp -nostdinc                    \
225		 $(addprefix -I,$(DTC_INCLUDE))                          \
226		 -undef -D__DTS__
227
228# Objtool arguments are also needed for modfinal with LTO, so we define
229# then here to avoid duplication.
230objtool_args =								\
231	$(if $(CONFIG_UNWINDER_ORC),orc generate,check)			\
232	$(if $(part-of-module), --module,)				\
233	$(if $(CONFIG_FRAME_POINTER),, --no-fp)				\
234	$(if $(or $(CONFIG_GCOV_KERNEL),$(CONFIG_LTO_CLANG)), 		\
235		--no-unreachable,)					\
236	$(if $(CONFIG_RETPOLINE), --retpoline,)				\
237	$(if $(CONFIG_X86_SMAP), --uaccess,)				\
238	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount,)
239
240# Useful for describing the dependency of composite objects
241# Usage:
242#   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
243define multi_depend
244$(foreach m, $(notdir $1), \
245	$(eval $(obj)/$m: \
246	$(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s)))))))
247endef
248
249quiet_cmd_copy = COPY    $@
250      cmd_copy = cp $< $@
251
252# Shipped files
253# ===========================================================================
254# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
255# the copy would be read-only as well, leading to an error when executing the
256# rule next time. Use 'cat' instead in order to generate a writable file.
257
258quiet_cmd_shipped = SHIPPED $@
259cmd_shipped = cat $< > $@
260
261$(obj)/%: $(src)/%_shipped
262	$(call cmd,shipped)
263
264# Commands useful for building a boot image
265# ===========================================================================
266#
267#	Use as following:
268#
269#	target: source(s) FORCE
270#		$(if_changed,ld/objcopy/gzip)
271#
272#	and add target to 'targets' so that we know we have to
273#	read in the saved command line
274
275# Linking
276# ---------------------------------------------------------------------------
277
278quiet_cmd_ld = LD      $@
279      cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
280
281# Archive
282# ---------------------------------------------------------------------------
283
284quiet_cmd_ar = AR      $@
285      cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
286
287# Objcopy
288# ---------------------------------------------------------------------------
289
290quiet_cmd_objcopy = OBJCOPY $@
291cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
292
293# Gzip
294# ---------------------------------------------------------------------------
295
296quiet_cmd_gzip = GZIP    $@
297      cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
298
299# DTC
300# ---------------------------------------------------------------------------
301DTC ?= $(objtree)/scripts/dtc/dtc
302DTC_FLAGS += -Wno-interrupt_provider
303
304# Disable noisy checks by default
305ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
306DTC_FLAGS += -Wno-unit_address_vs_reg \
307	-Wno-unit_address_format \
308	-Wno-avoid_unnecessary_addr_size \
309	-Wno-alias_paths \
310	-Wno-graph_child_address \
311	-Wno-simple_bus_reg \
312	-Wno-unique_unit_address \
313	-Wno-pci_device_reg
314endif
315
316ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),)
317DTC_FLAGS += -Wnode_name_chars_strict \
318	-Wproperty_name_chars_strict \
319	-Winterrupt_provider
320endif
321
322DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
323
324# Set -@ if the target is a base DTB that overlay is applied onto
325DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
326
327# Generate an assembly file to wrap the output of the device tree compiler
328quiet_cmd_dt_S_dtb= DTB     $@
329cmd_dt_S_dtb=						\
330{							\
331	echo '\#include <asm-generic/vmlinux.lds.h>'; 	\
332	echo '.section .dtb.init.rodata,"a"';		\
333	echo '.balign STRUCT_ALIGNMENT';		\
334	echo '.global __dtb_$(subst -,_,$(*F))_begin';	\
335	echo '__dtb_$(subst -,_,$(*F))_begin:';		\
336	echo '.incbin "$<" ';				\
337	echo '__dtb_$(subst -,_,$(*F))_end:';		\
338	echo '.global __dtb_$(subst -,_,$(*F))_end';	\
339	echo '.balign STRUCT_ALIGNMENT'; 		\
340} > $@
341
342$(obj)/%.dtb.S: $(obj)/%.dtb FORCE
343	$(call if_changed,dt_S_dtb)
344
345quiet_cmd_dtc = DTC     $@
346cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
347	$(DTC) -o $@ -b 0 \
348		$(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
349		-d $(depfile).dtc.tmp $(dtc-tmp) ; \
350	cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
351
352$(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
353	$(call if_changed_dep,dtc)
354
355$(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
356	$(call if_changed_dep,dtc)
357
358quiet_cmd_fdtoverlay = DTOVL   $@
359      cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
360
361$(multi-dtb-y): FORCE
362	$(call if_changed,fdtoverlay)
363$(call multi_depend, $(multi-dtb-y), .dtb, -dtbs)
364
365DT_CHECKER ?= dt-validate
366DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),,-m)
367DT_BINDING_DIR := Documentation/devicetree/bindings
368# DT_TMP_SCHEMA may be overridden from Documentation/devicetree/bindings/Makefile
369DT_TMP_SCHEMA ?= $(objtree)/$(DT_BINDING_DIR)/processed-schema.json
370
371quiet_cmd_dtb_check =	CHECK   $@
372      cmd_dtb_check =	$(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@
373
374define rule_dtc
375	$(call cmd_and_fixdep,dtc)
376	$(call cmd,dtb_check)
377endef
378
379$(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
380	$(call if_changed_rule,dtc)
381
382dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
383
384# Bzip2
385# ---------------------------------------------------------------------------
386
387# Bzip2 and LZMA do not include size in file... so we have to fake that;
388# append the size as a 32-bit littleendian number as gzip does.
389size_append = printf $(shell						\
390dec_size=0;								\
391for F in $(real-prereqs); do					\
392	fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F);	\
393	dec_size=$$(expr $$dec_size + $$fsize);				\
394done;									\
395printf "%08x\n" $$dec_size |						\
396	sed 's/\(..\)/\1 /g' | {					\
397		read ch0 ch1 ch2 ch3;					\
398		for ch in $$ch3 $$ch2 $$ch1 $$ch0; do			\
399			printf '%s%03o' '\\' $$((0x$$ch)); 		\
400		done;							\
401	}								\
402)
403
404quiet_cmd_bzip2 = BZIP2   $@
405      cmd_bzip2 = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
406
407# Lzma
408# ---------------------------------------------------------------------------
409
410quiet_cmd_lzma = LZMA    $@
411      cmd_lzma = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
412
413quiet_cmd_lzo = LZO     $@
414      cmd_lzo = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
415
416quiet_cmd_lz4 = LZ4     $@
417      cmd_lz4 = { cat $(real-prereqs) | $(LZ4) -l -c1 stdin stdout; \
418                  $(size_append); } > $@
419
420# U-Boot mkimage
421# ---------------------------------------------------------------------------
422
423MKIMAGE := $(srctree)/scripts/mkuboot.sh
424
425# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
426# the number of overrides in arch makefiles
427UIMAGE_ARCH ?= $(SRCARCH)
428UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)
429UIMAGE_OPTS-y ?=
430UIMAGE_TYPE ?= kernel
431UIMAGE_LOADADDR ?= arch_must_set_this
432UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
433UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
434
435quiet_cmd_uimage = UIMAGE  $@
436      cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
437			-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
438			-T $(UIMAGE_TYPE) \
439			-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
440			-n $(UIMAGE_NAME) -d $< $@
441
442# XZ
443# ---------------------------------------------------------------------------
444# Use xzkern to compress the kernel image and xzmisc to compress other things.
445#
446# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
447# of the kernel decompressor. A BCJ filter is used if it is available for
448# the target architecture. xzkern also appends uncompressed size of the data
449# using size_append. The .xz format has the size information available at
450# the end of the file too, but it's in more complex format and it's good to
451# avoid changing the part of the boot code that reads the uncompressed size.
452# Note that the bytes added by size_append will make the xz tool think that
453# the file is corrupt. This is expected.
454#
455# xzmisc doesn't use size_append, so it can be used to create normal .xz
456# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
457# big dictionary would increase the memory usage too much in the multi-call
458# decompression mode. A BCJ filter isn't used either.
459quiet_cmd_xzkern = XZKERN  $@
460      cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
461                     $(size_append); } > $@
462
463quiet_cmd_xzmisc = XZMISC  $@
464      cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
465
466# ZSTD
467# ---------------------------------------------------------------------------
468# Appends the uncompressed size of the data using size_append. The .zst
469# format has the size information available at the beginning of the file too,
470# but it's in a more complex format and it's good to avoid changing the part
471# of the boot code that reads the uncompressed size.
472#
473# Note that the bytes added by size_append will make the zstd tool think that
474# the file is corrupt. This is expected.
475#
476# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
477# 128 MB. zstd22 is used for kernel compression because it is decompressed in a
478# single pass, so zstd doesn't need to allocate a window buffer. When streaming
479# decompression is used, like initramfs decompression, zstd22 should likely not
480# be used because it would require zstd to allocate a 128 MB buffer.
481
482quiet_cmd_zstd = ZSTD    $@
483      cmd_zstd = { cat $(real-prereqs) | $(ZSTD) -19; $(size_append); } > $@
484
485quiet_cmd_zstd22 = ZSTD22  $@
486      cmd_zstd22 = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
487
488# ASM offsets
489# ---------------------------------------------------------------------------
490
491# Default sed regexp - multiline due to syntax constraints
492#
493# Use [:space:] because LLVM's integrated assembler inserts <tab> around
494# the .ascii directive whereas GCC keeps the <space> as-is.
495define sed-offsets
496	's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
497	/^->/{s:->#\(.*\):/* \1 */:; \
498	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
499	s:->::; p;}'
500endef
501
502# Use filechk to avoid rebuilds when a header changes, but the resulting file
503# does not
504define filechk_offsets
505	 echo "#ifndef $2"; \
506	 echo "#define $2"; \
507	 echo "/*"; \
508	 echo " * DO NOT MODIFY."; \
509	 echo " *"; \
510	 echo " * This file was generated by Kbuild"; \
511	 echo " */"; \
512	 echo ""; \
513	 sed -ne $(sed-offsets) < $<; \
514	 echo ""; \
515	 echo "#endif"
516endef
517