xref: /linux/scripts/Makefile.lib (revision bbcd53c960713507ae764bf81970651b5577b95a)
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) by calling $(call suffix-search,foo.o,-objs -y)
48suffix-search = $(strip $(foreach s, $2, $($(1:.o=$s))))
49# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
50multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2 -), $m)))
51multi-obj-y := $(call multi-search,$(obj-y),-objs -y)
52multi-obj-m := $(call multi-search,$(obj-m),-objs -y -m)
53multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
54
55# Replace multi-part objects by their individual parts,
56# including built-in.a from subdirectories
57real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2 -), $(call suffix-search, $m, $2), $m))
58real-obj-y := $(call real-search, $(obj-y),-objs -y)
59real-obj-m := $(call real-search, $(obj-m),-objs -y -m)
60
61always-y += $(always-m)
62
63# hostprogs-always-y += foo
64# ... is a shorthand for
65# hostprogs += foo
66# always-y  += foo
67hostprogs += $(hostprogs-always-y) $(hostprogs-always-m)
68always-y += $(hostprogs-always-y) $(hostprogs-always-m)
69
70# userprogs-always-y is likewise.
71userprogs += $(userprogs-always-y) $(userprogs-always-m)
72always-y += $(userprogs-always-y) $(userprogs-always-m)
73
74# DTB
75# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
76dtb-$(CONFIG_OF_ALL_DTBS)       += $(dtb-)
77
78# List all dtbs to be generated by fdtoverlay
79overlay-y := $(foreach m,$(dtb-y), $(if $(strip $($(m:.dtb=-dtbs))),$(m),))
80
81# Generate symbols for the base files so overlays can be applied to them.
82$(foreach m,$(overlay-y), $(eval DTC_FLAGS_$(basename $(firstword $($(m:.dtb=-dtbs)))) += -@))
83
84# Add base dtb and overlay dtbo
85dtb-y += $(foreach m,$(overlay-y), $($(m:.dtb=-dtbs)))
86
87always-y			+= $(dtb-y)
88
89ifneq ($(CHECK_DTBS),)
90# Don't run schema checks for dtbs created by fdtoverlay as they don't
91# have corresponding dts files.
92dt-yaml-y := $(filter-out $(overlay-y),$(dtb-y))
93
94always-y += $(patsubst %.dtb,%.dt.yaml, $(dt-yaml-y))
95always-y += $(patsubst %.dtbo,%.dt.yaml, $(dt-yaml-y))
96endif
97
98# Add subdir path
99
100extra-y		:= $(addprefix $(obj)/,$(extra-y))
101always-y	:= $(addprefix $(obj)/,$(always-y))
102targets		:= $(addprefix $(obj)/,$(targets))
103obj-m		:= $(addprefix $(obj)/,$(obj-m))
104lib-y		:= $(addprefix $(obj)/,$(lib-y))
105real-obj-y	:= $(addprefix $(obj)/,$(real-obj-y))
106real-obj-m	:= $(addprefix $(obj)/,$(real-obj-m))
107multi-obj-m	:= $(addprefix $(obj)/, $(multi-obj-m))
108subdir-ym	:= $(addprefix $(obj)/,$(subdir-ym))
109
110# Finds the multi-part object the current object will be linked into.
111# If the object belongs to two or more multi-part objects, list them all.
112modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
113		$(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$(m:.o=))))
114
115__modname = $(if $(modname-multi),$(modname-multi),$(basetarget))
116
117modname = $(subst $(space),:,$(__modname))
118modfile = $(addprefix $(obj)/,$(__modname))
119
120# target with $(obj)/ and its suffix stripped
121target-stem = $(basename $(patsubst $(obj)/%,%,$@))
122
123# These flags are needed for modversions and compiling, so we define them here
124# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
125# end up in (or would, if it gets compiled in)
126name-fix-token = $(subst $(comma),_,$(subst -,_,$1))
127name-fix = $(call stringify,$(call name-fix-token,$1))
128basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
129modname_flags  = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \
130		 -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname))
131modfile_flags  = -DKBUILD_MODFILE=$(call stringify,$(modfile))
132
133_c_flags       = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
134                     $(filter-out $(ccflags-remove-y), \
135                         $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
136                     $(CFLAGS_$(target-stem).o))
137_a_flags       = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
138                     $(filter-out $(asflags-remove-y), \
139                         $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
140                     $(AFLAGS_$(target-stem).o))
141_cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
142
143#
144# Enable gcov profiling flags for a file, directory or for all files depending
145# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
146# (in this order)
147#
148ifeq ($(CONFIG_GCOV_KERNEL),y)
149_c_flags += $(if $(patsubst n%,, \
150		$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
151		$(CFLAGS_GCOV))
152endif
153
154#
155# Enable address sanitizer flags for kernel except some files or directories
156# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
157#
158ifeq ($(CONFIG_KASAN),y)
159ifneq ($(CONFIG_KASAN_HW_TAGS),y)
160_c_flags += $(if $(patsubst n%,, \
161		$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
162		$(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
163endif
164endif
165
166ifeq ($(CONFIG_UBSAN),y)
167_c_flags += $(if $(patsubst n%,, \
168		$(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
169		$(CFLAGS_UBSAN))
170endif
171
172ifeq ($(CONFIG_KCOV),y)
173_c_flags += $(if $(patsubst n%,, \
174	$(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
175	$(CFLAGS_KCOV))
176endif
177
178#
179# Enable KCSAN flags except some files or directories we don't want to check
180# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
181#
182ifeq ($(CONFIG_KCSAN),y)
183_c_flags += $(if $(patsubst n%,, \
184	$(KCSAN_SANITIZE_$(basetarget).o)$(KCSAN_SANITIZE)y), \
185	$(CFLAGS_KCSAN))
186endif
187
188# $(srctree)/$(src) for including checkin headers from generated source files
189# $(objtree)/$(obj) for including generated headers from checkin source files
190ifeq ($(KBUILD_EXTMOD),)
191ifdef building_out_of_srctree
192_c_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
193_a_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
194_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
195endif
196endif
197
198part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
199quiet_modtag = $(if $(part-of-module),[M],   )
200
201modkern_cflags =                                          \
202	$(if $(part-of-module),                           \
203		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
204		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
205
206modkern_aflags = $(if $(part-of-module),				\
207			$(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE),	\
208			$(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))
209
210c_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
211		 -include $(srctree)/include/linux/compiler_types.h       \
212		 $(_c_flags) $(modkern_cflags)                           \
213		 $(basename_flags) $(modname_flags)
214
215a_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
216		 $(_a_flags) $(modkern_aflags)
217
218cpp_flags      = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
219		 $(_cpp_flags)
220
221ld_flags       = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
222
223DTC_INCLUDE    := $(srctree)/scripts/dtc/include-prefixes
224
225dtc_cpp_flags  = -Wp,-MMD,$(depfile).pre.tmp -nostdinc                    \
226		 $(addprefix -I,$(DTC_INCLUDE))                          \
227		 -undef -D__DTS__
228
229# Objtool arguments are also needed for modfinal with LTO, so we define
230# then here to avoid duplication.
231objtool_args =								\
232	$(if $(CONFIG_UNWINDER_ORC),orc generate,check)			\
233	$(if $(part-of-module), --module,)				\
234	$(if $(CONFIG_FRAME_POINTER),, --no-fp)				\
235	$(if $(or $(CONFIG_GCOV_KERNEL),$(CONFIG_LTO_CLANG)), 		\
236		--no-unreachable,)					\
237	$(if $(CONFIG_RETPOLINE), --retpoline,)				\
238	$(if $(CONFIG_X86_SMAP), --uaccess,)				\
239	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount,)
240
241# Useful for describing the dependency of composite objects
242# Usage:
243#   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
244define multi_depend
245$(foreach m, $(notdir $1), \
246	$(eval $(obj)/$m: \
247	$(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s)))))))
248endef
249
250quiet_cmd_copy = COPY    $@
251      cmd_copy = cp $< $@
252
253# Shipped files
254# ===========================================================================
255
256quiet_cmd_shipped = SHIPPED $@
257cmd_shipped = cat $< > $@
258
259$(obj)/%: $(src)/%_shipped
260	$(call cmd,shipped)
261
262# Commands useful for building a boot image
263# ===========================================================================
264#
265#	Use as following:
266#
267#	target: source(s) FORCE
268#		$(if_changed,ld/objcopy/gzip)
269#
270#	and add target to 'targets' so that we know we have to
271#	read in the saved command line
272
273# Linking
274# ---------------------------------------------------------------------------
275
276quiet_cmd_ld = LD      $@
277      cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
278
279# Archive
280# ---------------------------------------------------------------------------
281
282quiet_cmd_ar = AR      $@
283      cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
284
285# Objcopy
286# ---------------------------------------------------------------------------
287
288quiet_cmd_objcopy = OBJCOPY $@
289cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
290
291# Gzip
292# ---------------------------------------------------------------------------
293
294quiet_cmd_gzip = GZIP    $@
295      cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
296
297# DTC
298# ---------------------------------------------------------------------------
299DTC ?= $(objtree)/scripts/dtc/dtc
300DTC_FLAGS += -Wno-interrupt_provider
301
302# Disable noisy checks by default
303ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
304DTC_FLAGS += -Wno-unit_address_vs_reg \
305	-Wno-unit_address_format \
306	-Wno-avoid_unnecessary_addr_size \
307	-Wno-alias_paths \
308	-Wno-graph_child_address \
309	-Wno-simple_bus_reg \
310	-Wno-unique_unit_address \
311	-Wno-pci_device_reg
312endif
313
314ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),)
315DTC_FLAGS += -Wnode_name_chars_strict \
316	-Wproperty_name_chars_strict \
317	-Winterrupt_provider
318endif
319
320DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
321
322# Generate an assembly file to wrap the output of the device tree compiler
323quiet_cmd_dt_S_dtb= DTB     $@
324cmd_dt_S_dtb=						\
325{							\
326	echo '\#include <asm-generic/vmlinux.lds.h>'; 	\
327	echo '.section .dtb.init.rodata,"a"';		\
328	echo '.balign STRUCT_ALIGNMENT';		\
329	echo '.global __dtb_$(subst -,_,$(*F))_begin';	\
330	echo '__dtb_$(subst -,_,$(*F))_begin:';		\
331	echo '.incbin "$<" ';				\
332	echo '__dtb_$(subst -,_,$(*F))_end:';		\
333	echo '.global __dtb_$(subst -,_,$(*F))_end';	\
334	echo '.balign STRUCT_ALIGNMENT'; 		\
335} > $@
336
337$(obj)/%.dtb.S: $(obj)/%.dtb FORCE
338	$(call if_changed,dt_S_dtb)
339
340quiet_cmd_dtc = DTC     $@
341cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
342	$(DTC) -o $@ -b 0 \
343		$(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
344		-d $(depfile).dtc.tmp $(dtc-tmp) ; \
345	cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
346
347$(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
348	$(call if_changed_dep,dtc)
349
350$(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
351	$(call if_changed_dep,dtc)
352
353overlay-y := $(addprefix $(obj)/, $(overlay-y))
354
355quiet_cmd_fdtoverlay = DTOVL   $@
356      cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
357
358$(overlay-y): FORCE
359	$(call if_changed,fdtoverlay)
360$(call multi_depend, $(overlay-y), .dtb, -dtbs)
361
362DT_CHECKER ?= dt-validate
363DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),,-m)
364DT_BINDING_DIR := Documentation/devicetree/bindings
365# DT_TMP_SCHEMA may be overridden from Documentation/devicetree/bindings/Makefile
366DT_TMP_SCHEMA ?= $(objtree)/$(DT_BINDING_DIR)/processed-schema.json
367
368quiet_cmd_dtb_check =	CHECK   $@
369      cmd_dtb_check =	$(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@
370
371define rule_dtc
372	$(call cmd_and_fixdep,dtc)
373	$(call cmd,dtb_check)
374endef
375
376$(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
377	$(call if_changed_rule,dtc)
378
379dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
380
381# Bzip2
382# ---------------------------------------------------------------------------
383
384# Bzip2 and LZMA do not include size in file... so we have to fake that;
385# append the size as a 32-bit littleendian number as gzip does.
386size_append = printf $(shell						\
387dec_size=0;								\
388for F in $(real-prereqs); do					\
389	fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F);	\
390	dec_size=$$(expr $$dec_size + $$fsize);				\
391done;									\
392printf "%08x\n" $$dec_size |						\
393	sed 's/\(..\)/\1 /g' | {					\
394		read ch0 ch1 ch2 ch3;					\
395		for ch in $$ch3 $$ch2 $$ch1 $$ch0; do			\
396			printf '%s%03o' '\\' $$((0x$$ch)); 		\
397		done;							\
398	}								\
399)
400
401quiet_cmd_bzip2 = BZIP2   $@
402      cmd_bzip2 = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
403
404# Lzma
405# ---------------------------------------------------------------------------
406
407quiet_cmd_lzma = LZMA    $@
408      cmd_lzma = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
409
410quiet_cmd_lzo = LZO     $@
411      cmd_lzo = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
412
413quiet_cmd_lz4 = LZ4     $@
414      cmd_lz4 = { cat $(real-prereqs) | $(LZ4) -l -c1 stdin stdout; \
415                  $(size_append); } > $@
416
417# U-Boot mkimage
418# ---------------------------------------------------------------------------
419
420MKIMAGE := $(srctree)/scripts/mkuboot.sh
421
422# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
423# the number of overrides in arch makefiles
424UIMAGE_ARCH ?= $(SRCARCH)
425UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)
426UIMAGE_OPTS-y ?=
427UIMAGE_TYPE ?= kernel
428UIMAGE_LOADADDR ?= arch_must_set_this
429UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
430UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
431
432quiet_cmd_uimage = UIMAGE  $@
433      cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
434			-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
435			-T $(UIMAGE_TYPE) \
436			-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
437			-n $(UIMAGE_NAME) -d $< $@
438
439# XZ
440# ---------------------------------------------------------------------------
441# Use xzkern to compress the kernel image and xzmisc to compress other things.
442#
443# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
444# of the kernel decompressor. A BCJ filter is used if it is available for
445# the target architecture. xzkern also appends uncompressed size of the data
446# using size_append. The .xz format has the size information available at
447# the end of the file too, but it's in more complex format and it's good to
448# avoid changing the part of the boot code that reads the uncompressed size.
449# Note that the bytes added by size_append will make the xz tool think that
450# the file is corrupt. This is expected.
451#
452# xzmisc doesn't use size_append, so it can be used to create normal .xz
453# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
454# big dictionary would increase the memory usage too much in the multi-call
455# decompression mode. A BCJ filter isn't used either.
456quiet_cmd_xzkern = XZKERN  $@
457      cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
458                     $(size_append); } > $@
459
460quiet_cmd_xzmisc = XZMISC  $@
461      cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
462
463# ZSTD
464# ---------------------------------------------------------------------------
465# Appends the uncompressed size of the data using size_append. The .zst
466# format has the size information available at the beginning of the file too,
467# but it's in a more complex format and it's good to avoid changing the part
468# of the boot code that reads the uncompressed size.
469#
470# Note that the bytes added by size_append will make the zstd tool think that
471# the file is corrupt. This is expected.
472#
473# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
474# 128 MB. zstd22 is used for kernel compression because it is decompressed in a
475# single pass, so zstd doesn't need to allocate a window buffer. When streaming
476# decompression is used, like initramfs decompression, zstd22 should likely not
477# be used because it would require zstd to allocate a 128 MB buffer.
478
479quiet_cmd_zstd = ZSTD    $@
480      cmd_zstd = { cat $(real-prereqs) | $(ZSTD) -19; $(size_append); } > $@
481
482quiet_cmd_zstd22 = ZSTD22  $@
483      cmd_zstd22 = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
484
485# ASM offsets
486# ---------------------------------------------------------------------------
487
488# Default sed regexp - multiline due to syntax constraints
489#
490# Use [:space:] because LLVM's integrated assembler inserts <tab> around
491# the .ascii directive whereas GCC keeps the <space> as-is.
492define sed-offsets
493	's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
494	/^->/{s:->#\(.*\):/* \1 */:; \
495	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
496	s:->::; p;}'
497endef
498
499# Use filechk to avoid rebuilds when a header changes, but the resulting file
500# does not
501define filechk_offsets
502	 echo "#ifndef $2"; \
503	 echo "#define $2"; \
504	 echo "/*"; \
505	 echo " * DO NOT MODIFY."; \
506	 echo " *"; \
507	 echo " * This file was generated by Kbuild"; \
508	 echo " */"; \
509	 echo ""; \
510	 sed -ne $(sed-offsets) < $<; \
511	 echo ""; \
512	 echo "#endif"
513endef
514