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1# SPDX-License-Identifier: GPL-2.0
2# ==========================================================================
3# Building
4# ==========================================================================
5
6src := $(obj)
7
8PHONY := __build
9__build:
10
11# Init all relevant variables used in kbuild files so
12# 1) they have correct type
13# 2) they do not inherit any value from the environment
14obj-y :=
15obj-m :=
16lib-y :=
17lib-m :=
18always :=
19always-y :=
20always-m :=
21targets :=
22subdir-y :=
23subdir-m :=
24EXTRA_AFLAGS   :=
25EXTRA_CFLAGS   :=
26EXTRA_CPPFLAGS :=
27EXTRA_LDFLAGS  :=
28asflags-y  :=
29ccflags-y  :=
30cppflags-y :=
31ldflags-y  :=
32
33subdir-asflags-y :=
34subdir-ccflags-y :=
35
36# Read auto.conf if it exists, otherwise ignore
37-include include/config/auto.conf
38
39include scripts/Kbuild.include
40
41# The filename Kbuild has precedence over Makefile
42kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
43kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
44include $(kbuild-file)
45
46include scripts/Makefile.lib
47
48# Do not include hostprogs rules unless needed.
49# $(sort ...) is used here to remove duplicated words and excessive spaces.
50hostprogs := $(sort $(hostprogs))
51ifneq ($(hostprogs),)
52include scripts/Makefile.host
53endif
54
55# Do not include userprogs rules unless needed.
56# $(sort ...) is used here to remove duplicated words and excessive spaces.
57userprogs := $(sort $(userprogs))
58ifneq ($(userprogs),)
59include scripts/Makefile.userprogs
60endif
61
62ifndef obj
63$(warning kbuild: Makefile.build is included improperly)
64endif
65
66ifeq ($(need-modorder),)
67ifneq ($(obj-m),)
68$(warning $(patsubst %.o,'%.ko',$(obj-m)) will not be built even though obj-m is specified.)
69$(warning You cannot use subdir-y/m to visit a module Makefile. Use obj-y/m instead.)
70endif
71endif
72
73# ===========================================================================
74
75# subdir-builtin and subdir-modorder may contain duplications. Use $(sort ...)
76subdir-builtin := $(sort $(filter %/built-in.a, $(real-obj-y)))
77subdir-modorder := $(sort $(filter %/modules.order, $(obj-m)))
78
79targets-for-builtin := $(extra-y)
80
81ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
82targets-for-builtin += $(obj)/lib.a
83endif
84
85ifdef need-builtin
86targets-for-builtin += $(obj)/built-in.a
87endif
88
89targets-for-modules := $(patsubst %.o, %.mod, $(filter %.o, $(obj-m)))
90
91ifdef need-modorder
92targets-for-modules += $(obj)/modules.order
93endif
94
95targets += $(targets-for-builtin) $(targets-for-modules)
96
97# Linus' kernel sanity checking tool
98ifeq ($(KBUILD_CHECKSRC),1)
99  quiet_cmd_checksrc       = CHECK   $<
100        cmd_checksrc       = $(CHECK) $(CHECKFLAGS) $(c_flags) $<
101else ifeq ($(KBUILD_CHECKSRC),2)
102  quiet_cmd_force_checksrc = CHECK   $<
103        cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $<
104endif
105
106ifneq ($(KBUILD_EXTRA_WARN),)
107  cmd_checkdoc = $(srctree)/scripts/kernel-doc -none $<
108endif
109
110# Compile C sources (.c)
111# ---------------------------------------------------------------------------
112
113quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
114      cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS) $(CC_FLAGS_LTO), $(c_flags)) -fverbose-asm -S -o $@ $<
115
116$(obj)/%.s: $(src)/%.c FORCE
117	$(call if_changed_dep,cc_s_c)
118
119quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
120cmd_cpp_i_c       = $(CPP) $(c_flags) -o $@ $<
121
122$(obj)/%.i: $(src)/%.c FORCE
123	$(call if_changed_dep,cpp_i_c)
124
125# These mirror gensymtypes_S and co below, keep them in synch.
126cmd_gensymtypes_c =                                                         \
127    $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
128    scripts/genksyms/genksyms $(if $(1), -T $(2))                           \
129     $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
130     $(if $(KBUILD_PRESERVE),-p)                                            \
131     -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
132
133quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
134cmd_cc_symtypes_c =                                                         \
135    $(call cmd_gensymtypes_c,true,$@) >/dev/null;                           \
136    test -s $@ || rm -f $@
137
138$(obj)/%.symtypes : $(src)/%.c FORCE
139	$(call cmd,cc_symtypes_c)
140
141# LLVM assembly
142# Generate .ll files from .c
143quiet_cmd_cc_ll_c = CC $(quiet_modtag)  $@
144      cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
145
146$(obj)/%.ll: $(src)/%.c FORCE
147	$(call if_changed_dep,cc_ll_c)
148
149# C (.c) files
150# The C file is compiled and updated dependency information is generated.
151# (See cmd_cc_o_c + relevant part of rule_cc_o_c)
152
153quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
154      cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
155
156ifdef CONFIG_MODVERSIONS
157# When module versioning is enabled the following steps are executed:
158# o compile a <file>.o from <file>.c
159# o if <file>.o doesn't contain a __ksymtab version, i.e. does
160#   not export symbols, it's done.
161# o otherwise, we calculate symbol versions using the good old
162#   genksyms on the preprocessed source and postprocess them in a way
163#   that they are usable as a linker script
164# o generate .tmp_<file>.o from <file>.o using the linker to
165#   replace the unresolved symbols __crc_exported_symbol with
166#   the actual value of the checksum generated by genksyms
167# o remove .tmp_<file>.o to <file>.o
168
169ifdef CONFIG_LTO_CLANG
170# Generate .o.symversions files for each .o with exported symbols, and link these
171# to the kernel and/or modules at the end.
172cmd_modversions_c =								\
173	if $(NM) $@ 2>/dev/null | grep -q __ksymtab; then			\
174		$(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
175		    > $@.symversions;						\
176	fi;
177else
178cmd_modversions_c =								\
179	if $(OBJDUMP) -h $@ | grep -q __ksymtab; then				\
180		$(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
181		    > $(@D)/.tmp_$(@F:.o=.ver);					\
182										\
183		$(LD) $(KBUILD_LDFLAGS) -r -o $(@D)/.tmp_$(@F) $@ 		\
184			-T $(@D)/.tmp_$(@F:.o=.ver);				\
185		mv -f $(@D)/.tmp_$(@F) $@;					\
186		rm -f $(@D)/.tmp_$(@F:.o=.ver);					\
187	fi
188endif
189endif
190
191ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
192# compiler will not generate __mcount_loc use recordmcount or recordmcount.pl
193ifdef BUILD_C_RECORDMCOUNT
194ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
195  RECORDMCOUNT_FLAGS = -w
196endif
197# Due to recursion, we must skip empty.o.
198# The empty.o file is created in the make process in order to determine
199# the target endianness and word size. It is made before all other C
200# files, including recordmcount.
201sub_cmd_record_mcount =					\
202	if [ $(@) != "scripts/mod/empty.o" ]; then	\
203		$(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";	\
204	fi;
205recordmcount_source := $(srctree)/scripts/recordmcount.c \
206		    $(srctree)/scripts/recordmcount.h
207else
208sub_cmd_record_mcount = perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
209	"$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
210	"$(if $(CONFIG_64BIT),64,32)" \
211	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS)" \
212	"$(LD) $(KBUILD_LDFLAGS)" "$(NM)" "$(RM)" "$(MV)" \
213	"$(if $(part-of-module),1,0)" "$(@)";
214recordmcount_source := $(srctree)/scripts/recordmcount.pl
215endif # BUILD_C_RECORDMCOUNT
216cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)),	\
217	$(sub_cmd_record_mcount))
218endif # CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
219
220ifdef CONFIG_STACK_VALIDATION
221ifndef CONFIG_LTO_CLANG
222ifneq ($(SKIP_STACK_VALIDATION),1)
223
224__objtool_obj := $(objtree)/tools/objtool/objtool
225
226# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
227# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
228# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
229cmd_objtool = $(if $(patsubst y%,, \
230	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
231	$(__objtool_obj) $(objtool_args) $@)
232objtool_obj = $(if $(patsubst y%,, \
233	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
234	$(__objtool_obj))
235
236endif # SKIP_STACK_VALIDATION
237endif # CONFIG_LTO_CLANG
238endif # CONFIG_STACK_VALIDATION
239
240# Rebuild all objects when objtool changes, or is enabled/disabled.
241objtool_dep = $(objtool_obj)					\
242	      $(wildcard include/config/orc/unwinder.h		\
243			 include/config/stack/validation.h)
244
245ifdef CONFIG_TRIM_UNUSED_KSYMS
246cmd_gen_ksymdeps = \
247	$(CONFIG_SHELL) $(srctree)/scripts/gen_ksymdeps.sh $@ >> $(dot-target).cmd
248
249# List module undefined symbols
250undefined_syms = $(NM) $< | $(AWK) '$$1 == "U" { printf("%s%s", x++ ? " " : "", $$2) }';
251endif
252
253define rule_cc_o_c
254	$(call cmd_and_fixdep,cc_o_c)
255	$(call cmd,gen_ksymdeps)
256	$(call cmd,checksrc)
257	$(call cmd,checkdoc)
258	$(call cmd,objtool)
259	$(call cmd,modversions_c)
260	$(call cmd,record_mcount)
261endef
262
263define rule_as_o_S
264	$(call cmd_and_fixdep,as_o_S)
265	$(call cmd,gen_ksymdeps)
266	$(call cmd,objtool)
267	$(call cmd,modversions_S)
268endef
269
270# Built-in and composite module parts
271.SECONDEXPANSION:
272$(obj)/%.o: $(src)/%.c $(recordmcount_source) $$(objtool_dep) FORCE
273	$(call if_changed_rule,cc_o_c)
274	$(call cmd,force_checksrc)
275
276cmd_mod = { \
277	echo $(if $($*-objs)$($*-y)$($*-m), $(addprefix $(obj)/, $($*-objs) $($*-y) $($*-m)), $(@:.mod=.o)); \
278	$(undefined_syms) echo; \
279	} > $@
280
281$(obj)/%.mod: $(obj)/%.o FORCE
282	$(call if_changed,mod)
283
284quiet_cmd_cc_lst_c = MKLST   $@
285      cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
286		     $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
287				     System.map $(OBJDUMP) > $@
288
289$(obj)/%.lst: $(src)/%.c FORCE
290	$(call if_changed_dep,cc_lst_c)
291
292# Compile assembler sources (.S)
293# ---------------------------------------------------------------------------
294
295# .S file exports must have their C prototypes defined in asm/asm-prototypes.h
296# or a file that it includes, in order to get versioned symbols. We build a
297# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
298# the .S file (with trailing ';'), and run genksyms on that, to extract vers.
299#
300# This is convoluted. The .S file must first be preprocessed to run guards and
301# expand names, then the resulting exports must be constructed into plain
302# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
303# to make the genksyms input.
304#
305# These mirror gensymtypes_c and co above, keep them in synch.
306cmd_gensymtypes_S =                                                         \
307   { echo "\#include <linux/kernel.h>" ;                                    \
308     echo "\#include <asm/asm-prototypes.h>" ;                              \
309    $(CPP) $(a_flags) $< |                                                  \
310     grep "\<___EXPORT_SYMBOL\>" |                                          \
311     sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ; } | \
312    $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
313    scripts/genksyms/genksyms $(if $(1), -T $(2))                           \
314     $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
315     $(if $(KBUILD_PRESERVE),-p)                                            \
316     -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
317
318quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
319cmd_cc_symtypes_S =                                                         \
320    $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
321    test -s $@ || rm -f $@
322
323$(obj)/%.symtypes : $(src)/%.S FORCE
324	$(call cmd,cc_symtypes_S)
325
326
327quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
328cmd_cpp_s_S       = $(CPP) $(a_flags) -o $@ $<
329
330$(obj)/%.s: $(src)/%.S FORCE
331	$(call if_changed_dep,cpp_s_S)
332
333quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
334      cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
335
336ifdef CONFIG_ASM_MODVERSIONS
337
338# versioning matches the C process described above, with difference that
339# we parse asm-prototypes.h C header to get function definitions.
340
341cmd_modversions_S =								\
342	if $(OBJDUMP) -h $@ | grep -q __ksymtab; then				\
343		$(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
344		    > $(@D)/.tmp_$(@F:.o=.ver);					\
345										\
346		$(LD) $(KBUILD_LDFLAGS) -r -o $(@D)/.tmp_$(@F) $@ 		\
347			-T $(@D)/.tmp_$(@F:.o=.ver);				\
348		mv -f $(@D)/.tmp_$(@F) $@;					\
349		rm -f $(@D)/.tmp_$(@F:.o=.ver);					\
350	fi
351endif
352
353$(obj)/%.o: $(src)/%.S $$(objtool_dep) FORCE
354	$(call if_changed_rule,as_o_S)
355
356targets += $(filter-out $(subdir-builtin), $(real-obj-y))
357targets += $(filter-out $(subdir-modorder), $(real-obj-m))
358targets += $(lib-y) $(always-y) $(MAKECMDGOALS)
359
360# Linker scripts preprocessor (.lds.S -> .lds)
361# ---------------------------------------------------------------------------
362quiet_cmd_cpp_lds_S = LDS     $@
363      cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -U$(ARCH) \
364	                     -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
365
366$(obj)/%.lds: $(src)/%.lds.S FORCE
367	$(call if_changed_dep,cpp_lds_S)
368
369# ASN.1 grammar
370# ---------------------------------------------------------------------------
371quiet_cmd_asn1_compiler = ASN.1   $(basename $@).[ch]
372      cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
373				$(basename $@).c $(basename $@).h
374
375$(obj)/%.asn1.c $(obj)/%.asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
376	$(call cmd,asn1_compiler)
377
378# Build the compiled-in targets
379# ---------------------------------------------------------------------------
380
381# To build objects in subdirs, we need to descend into the directories
382$(subdir-builtin): $(obj)/%/built-in.a: $(obj)/% ;
383$(subdir-modorder): $(obj)/%/modules.order: $(obj)/% ;
384
385# combine symversions for later processing
386quiet_cmd_update_lto_symversions = SYMVER  $@
387ifeq ($(CONFIG_LTO_CLANG) $(CONFIG_MODVERSIONS),y y)
388      cmd_update_lto_symversions =					\
389	rm -f $@.symversions						\
390	$(foreach n, $(filter-out FORCE,$^),				\
391		$(if $(shell test -s $(n).symversions && echo y),	\
392			; cat $(n).symversions >> $@.symversions))
393else
394      cmd_update_lto_symversions = echo >/dev/null
395endif
396
397#
398# Rule to compile a set of .o files into one .a file (without symbol table)
399#
400
401quiet_cmd_ar_builtin = AR      $@
402      cmd_ar_builtin = rm -f $@; $(AR) cDPrST $@ $(real-prereqs)
403
404quiet_cmd_ar_and_symver = AR      $@
405      cmd_ar_and_symver = $(cmd_update_lto_symversions); $(cmd_ar_builtin)
406
407$(obj)/built-in.a: $(real-obj-y) FORCE
408	$(call if_changed,ar_and_symver)
409
410#
411# Rule to create modules.order file
412#
413# Create commands to either record .ko file or cat modules.order from
414# a subdirectory
415# Add $(obj-m) as the prerequisite to avoid updating the timestamp of
416# modules.order unless contained modules are updated.
417
418cmd_modules_order = { $(foreach m, $(real-prereqs), \
419	$(if $(filter %/modules.order, $m), cat $m, echo $(patsubst %.o,%.ko,$m));) :; } \
420	| $(AWK) '!x[$$0]++' - > $@
421
422$(obj)/modules.order: $(obj-m) FORCE
423	$(call if_changed,modules_order)
424
425#
426# Rule to compile a set of .o files into one .a file (with symbol table)
427#
428quiet_cmd_ar_lib = AR      $@
429      cmd_ar_lib = $(cmd_update_lto_symversions); $(cmd_ar)
430
431$(obj)/lib.a: $(lib-y) FORCE
432	$(call if_changed,ar_lib)
433
434# NOTE:
435# Do not replace $(filter %.o,^) with $(real-prereqs). When a single object
436# module is turned into a multi object module, $^ will contain header file
437# dependencies recorded in the .*.cmd file.
438ifdef CONFIG_LTO_CLANG
439quiet_cmd_link_multi-m = AR [M]  $@
440cmd_link_multi-m =						\
441	$(cmd_update_lto_symversions);				\
442	rm -f $@; 						\
443	$(AR) cDPrsT $@ $(filter %.o %.a,$^)
444else
445quiet_cmd_link_multi-m = LD [M]  $@
446      cmd_link_multi-m = $(LD) $(ld_flags) -r -o $@ $(filter %.o,$^)
447endif
448
449$(multi-used-m): FORCE
450	$(call if_changed,link_multi-m)
451$(call multi_depend, $(multi-used-m), .o, -objs -y -m)
452
453targets += $(multi-used-m)
454targets := $(filter-out $(PHONY), $(targets))
455
456# Add intermediate targets:
457# When building objects with specific suffix patterns, add intermediate
458# targets that the final targets are derived from.
459intermediate_targets = $(foreach sfx, $(2), \
460				$(patsubst %$(strip $(1)),%$(sfx), \
461					$(filter %$(strip $(1)), $(targets))))
462# %.asn1.o <- %.asn1.[ch] <- %.asn1
463# %.dtb.o <- %.dtb.S <- %.dtb <- %.dts
464# %.lex.o <- %.lex.c <- %.l
465# %.tab.o <- %.tab.[ch] <- %.y
466targets += $(call intermediate_targets, .asn1.o, .asn1.c .asn1.h) \
467	   $(call intermediate_targets, .dtb.o, .dtb.S .dtb) \
468	   $(call intermediate_targets, .lex.o, .lex.c) \
469	   $(call intermediate_targets, .tab.o, .tab.c .tab.h)
470
471# Build
472# ---------------------------------------------------------------------------
473
474ifdef single-build
475
476KBUILD_SINGLE_TARGETS := $(filter $(obj)/%, $(KBUILD_SINGLE_TARGETS))
477
478curdir-single := $(sort $(foreach x, $(KBUILD_SINGLE_TARGETS), \
479			$(if $(filter $(x) $(basename $(x)).o, $(targets)), $(x))))
480
481# Handle single targets without any rule: show "Nothing to be done for ..." or
482# "No rule to make target ..." depending on whether the target exists.
483unknown-single := $(filter-out $(addsuffix /%, $(subdir-ym)), \
484			$(filter-out $(curdir-single), $(KBUILD_SINGLE_TARGETS)))
485
486single-subdirs := $(foreach d, $(subdir-ym), \
487			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
488
489__build: $(curdir-single) $(single-subdirs)
490ifneq ($(unknown-single),)
491	$(Q)$(MAKE) -f /dev/null $(unknown-single)
492endif
493	@:
494
495ifeq ($(curdir-single),)
496# Nothing to do in this directory. Do not include any .*.cmd file for speed-up
497targets :=
498else
499targets += $(curdir-single)
500endif
501
502else
503
504__build: $(if $(KBUILD_BUILTIN), $(targets-for-builtin)) \
505	 $(if $(KBUILD_MODULES), $(targets-for-modules)) \
506	 $(subdir-ym) $(always-y)
507	@:
508
509endif
510
511# Descending
512# ---------------------------------------------------------------------------
513
514PHONY += $(subdir-ym)
515$(subdir-ym):
516	$(Q)$(MAKE) $(build)=$@ \
517	$(if $(filter $@/, $(KBUILD_SINGLE_TARGETS)),single-build=) \
518	need-builtin=$(if $(filter $@/built-in.a, $(subdir-builtin)),1) \
519	need-modorder=$(if $(filter $@/modules.order, $(subdir-modorder)),1)
520
521# Add FORCE to the prequisites of a target to force it to be always rebuilt.
522# ---------------------------------------------------------------------------
523
524PHONY += FORCE
525
526FORCE:
527
528# Read all saved command lines and dependencies for the $(targets) we
529# may be building above, using $(if_changed{,_dep}). As an
530# optimization, we don't need to read them if the target does not
531# exist, we will rebuild anyway in that case.
532
533existing-targets := $(wildcard $(sort $(targets)))
534
535-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
536
537# Create directories for object files if they do not exist
538obj-dirs := $(sort $(patsubst %/,%, $(dir $(targets))))
539# If targets exist, their directories apparently exist. Skip mkdir.
540existing-dirs := $(sort $(patsubst %/,%, $(dir $(existing-targets))))
541obj-dirs := $(strip $(filter-out $(existing-dirs), $(obj-dirs)))
542ifneq ($(obj-dirs),)
543$(shell mkdir -p $(obj-dirs))
544endif
545
546.PHONY: $(PHONY)
547