Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1# ==========================================================================
2# Building
3# ==========================================================================
4
5src := $(obj)
6
7PHONY := __build
8__build:
9
10# Init all relevant variables used in kbuild files so
11# 1) they have correct type
12# 2) they do not inherit any value from the environment
13obj-y :=
14obj-m :=
15lib-y :=
16lib-m :=
17always :=
18targets :=
19subdir-y :=
20subdir-m :=
21EXTRA_AFLAGS :=
22EXTRA_CFLAGS :=
23EXTRA_CPPFLAGS :=
24EXTRA_LDFLAGS :=
25asflags-y :=
26ccflags-y :=
27cppflags-y :=
28ldflags-y :=
29
30subdir-asflags-y :=
31subdir-ccflags-y :=
32
33# Read auto.conf if it exists, otherwise ignore
34-include include/config/auto.conf
35
36include scripts/Kbuild.include
37
38# For backward compatibility check that these variables do not change
39save-cflags := $(CFLAGS)
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 $(kbuild-file)
45
46# If the save-* variables changed error out
47ifeq ($(KBUILD_NOPEDANTIC),)
48 ifneq ("$(save-cflags)","$(CFLAGS)")
49 $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
50 endif
51endif
52
53include scripts/Makefile.lib
54
55ifdef host-progs
56ifneq ($(hostprogs-y),$(host-progs))
57$(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
58hostprogs-y += $(host-progs)
59endif
60endif
61
62# Do not include host rules unless needed
63ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
64include scripts/Makefile.host
65endif
66
67ifneq ($(KBUILD_SRC),)
68# Create output directory if not already present
69_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
70
71# Create directories for object files if directory does not exist
72# Needed when obj-y := dir/file.o syntax is used
73_dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
74endif
75
76ifndef obj
77$(warning kbuild: Makefile.build is included improperly)
78endif
79
80# ===========================================================================
81
82ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
83lib-target := $(obj)/lib.a
84obj-y += $(obj)/lib-ksyms.o
85endif
86
87ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
88builtin-target := $(obj)/built-in.o
89endif
90
91modorder-target := $(obj)/modules.order
92
93# We keep a list of all modules in $(MODVERDIR)
94
95__build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
96 $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
97 $(subdir-ym) $(always)
98 @:
99
100# Linus' kernel sanity checking tool
101ifneq ($(KBUILD_CHECKSRC),0)
102 ifeq ($(KBUILD_CHECKSRC),2)
103 quiet_cmd_force_checksrc = CHECK $<
104 cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
105 else
106 quiet_cmd_checksrc = CHECK $<
107 cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
108 endif
109endif
110
111# Do section mismatch analysis for each module/built-in.o
112ifdef CONFIG_DEBUG_SECTION_MISMATCH
113 cmd_secanalysis = ; scripts/mod/modpost $@
114endif
115
116# Compile C sources (.c)
117# ---------------------------------------------------------------------------
118
119# Default is built-in, unless we know otherwise
120modkern_cflags = \
121 $(if $(part-of-module), \
122 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
123 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
124quiet_modtag := $(empty) $(empty)
125
126$(real-objs-m) : part-of-module := y
127$(real-objs-m:.o=.i) : part-of-module := y
128$(real-objs-m:.o=.s) : part-of-module := y
129$(real-objs-m:.o=.lst): part-of-module := y
130
131$(real-objs-m) : quiet_modtag := [M]
132$(real-objs-m:.o=.i) : quiet_modtag := [M]
133$(real-objs-m:.o=.s) : quiet_modtag := [M]
134$(real-objs-m:.o=.lst): quiet_modtag := [M]
135
136$(obj-m) : quiet_modtag := [M]
137
138# Default for not multi-part modules
139modname = $(basetarget)
140
141$(multi-objs-m) : modname = $(modname-multi)
142$(multi-objs-m:.o=.i) : modname = $(modname-multi)
143$(multi-objs-m:.o=.s) : modname = $(modname-multi)
144$(multi-objs-m:.o=.lst) : modname = $(modname-multi)
145$(multi-objs-y) : modname = $(modname-multi)
146$(multi-objs-y:.o=.i) : modname = $(modname-multi)
147$(multi-objs-y:.o=.s) : modname = $(modname-multi)
148$(multi-objs-y:.o=.lst) : modname = $(modname-multi)
149
150quiet_cmd_cc_s_c = CC $(quiet_modtag) $@
151cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
152
153$(obj)/%.s: $(src)/%.c FORCE
154 $(call if_changed_dep,cc_s_c)
155
156quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
157cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $<
158
159$(obj)/%.i: $(src)/%.c FORCE
160 $(call if_changed_dep,cpp_i_c)
161
162# These mirror gensymtypes_S and co below, keep them in synch.
163cmd_gensymtypes_c = \
164 $(CPP) -D__GENKSYMS__ $(c_flags) $< | \
165 $(GENKSYMS) $(if $(1), -T $(2)) \
166 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \
167 $(if $(KBUILD_PRESERVE),-p) \
168 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
169
170quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
171cmd_cc_symtypes_c = \
172 set -e; \
173 $(call cmd_gensymtypes_c,true,$@) >/dev/null; \
174 test -s $@ || rm -f $@
175
176$(obj)/%.symtypes : $(src)/%.c FORCE
177 $(call cmd,cc_symtypes_c)
178
179# C (.c) files
180# The C file is compiled and updated dependency information is generated.
181# (See cmd_cc_o_c + relevant part of rule_cc_o_c)
182
183quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
184
185ifndef CONFIG_MODVERSIONS
186cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
187
188else
189# When module versioning is enabled the following steps are executed:
190# o compile a .tmp_<file>.o from <file>.c
191# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
192# not export symbols, we just rename .tmp_<file>.o to <file>.o and
193# are done.
194# o otherwise, we calculate symbol versions using the good old
195# genksyms on the preprocessed source and postprocess them in a way
196# that they are usable as a linker script
197# o generate <file>.o from .tmp_<file>.o using the linker to
198# replace the unresolved symbols __crc_exported_symbol with
199# the actual value of the checksum generated by genksyms
200
201cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
202
203cmd_modversions_c = \
204 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
205 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
206 > $(@D)/.tmp_$(@F:.o=.ver); \
207 \
208 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
209 -T $(@D)/.tmp_$(@F:.o=.ver); \
210 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
211 else \
212 mv -f $(@D)/.tmp_$(@F) $@; \
213 fi;
214endif
215
216ifdef CONFIG_FTRACE_MCOUNT_RECORD
217ifdef BUILD_C_RECORDMCOUNT
218ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
219 RECORDMCOUNT_FLAGS = -w
220endif
221# Due to recursion, we must skip empty.o.
222# The empty.o file is created in the make process in order to determine
223# the target endianness and word size. It is made before all other C
224# files, including recordmcount.
225sub_cmd_record_mcount = \
226 if [ $(@) != "scripts/mod/empty.o" ]; then \
227 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \
228 fi;
229recordmcount_source := $(srctree)/scripts/recordmcount.c \
230 $(srctree)/scripts/recordmcount.h
231else
232sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
233 "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
234 "$(if $(CONFIG_64BIT),64,32)" \
235 "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
236 "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
237 "$(if $(part-of-module),1,0)" "$(@)";
238recordmcount_source := $(srctree)/scripts/recordmcount.pl
239endif
240cmd_record_mcount = \
241 if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" = \
242 "$(CC_FLAGS_FTRACE)" ]; then \
243 $(sub_cmd_record_mcount) \
244 fi;
245endif
246
247ifdef CONFIG_STACK_VALIDATION
248ifneq ($(SKIP_STACK_VALIDATION),1)
249
250__objtool_obj := $(objtree)/tools/objtool/objtool
251
252objtool_args = check
253ifndef CONFIG_FRAME_POINTER
254objtool_args += --no-fp
255endif
256
257# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
258# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
259# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
260cmd_objtool = $(if $(patsubst y%,, \
261 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
262 $(__objtool_obj) $(objtool_args) "$(@)";)
263objtool_obj = $(if $(patsubst y%,, \
264 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
265 $(__objtool_obj))
266
267endif # SKIP_STACK_VALIDATION
268endif # CONFIG_STACK_VALIDATION
269
270define rule_cc_o_c
271 $(call echo-cmd,checksrc) $(cmd_checksrc) \
272 $(call cmd_and_fixdep,cc_o_c) \
273 $(cmd_modversions_c) \
274 $(cmd_objtool) \
275 $(call echo-cmd,record_mcount) $(cmd_record_mcount)
276endef
277
278define rule_as_o_S
279 $(call cmd_and_fixdep,as_o_S) \
280 $(cmd_modversions_S) \
281 $(cmd_objtool)
282endef
283
284# List module undefined symbols (or empty line if not enabled)
285ifdef CONFIG_TRIM_UNUSED_KSYMS
286cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
287else
288cmd_undef_syms = echo
289endif
290
291# Built-in and composite module parts
292$(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
293 $(call cmd,force_checksrc)
294 $(call if_changed_rule,cc_o_c)
295
296# Single-part modules are special since we need to mark them in $(MODVERDIR)
297
298$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
299 $(call cmd,force_checksrc)
300 $(call if_changed_rule,cc_o_c)
301 @{ echo $(@:.o=.ko); echo $@; \
302 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
303
304quiet_cmd_cc_lst_c = MKLST $@
305 cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
306 $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
307 System.map $(OBJDUMP) > $@
308
309$(obj)/%.lst: $(src)/%.c FORCE
310 $(call if_changed_dep,cc_lst_c)
311
312# Compile assembler sources (.S)
313# ---------------------------------------------------------------------------
314
315modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
316
317$(real-objs-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
318$(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
319
320# .S file exports must have their C prototypes defined in asm/asm-prototypes.h
321# or a file that it includes, in order to get versioned symbols. We build a
322# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
323# the .S file (with trailing ';'), and run genksyms on that, to extract vers.
324#
325# This is convoluted. The .S file must first be preprocessed to run guards and
326# expand names, then the resulting exports must be constructed into plain
327# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
328# to make the genksyms input.
329#
330# These mirror gensymtypes_c and co above, keep them in synch.
331cmd_gensymtypes_S = \
332 (echo "\#include <linux/kernel.h>" ; \
333 echo "\#include <asm/asm-prototypes.h>" ; \
334 $(CPP) $(a_flags) $< | \
335 grep "\<___EXPORT_SYMBOL\>" | \
336 sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
337 $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | \
338 $(GENKSYMS) $(if $(1), -T $(2)) \
339 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \
340 $(if $(KBUILD_PRESERVE),-p) \
341 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
342
343quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
344cmd_cc_symtypes_S = \
345 set -e; \
346 $(call cmd_gensymtypes_S,true,$@) >/dev/null; \
347 test -s $@ || rm -f $@
348
349$(obj)/%.symtypes : $(src)/%.S FORCE
350 $(call cmd,cc_symtypes_S)
351
352
353quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
354cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $<
355
356$(obj)/%.s: $(src)/%.S FORCE
357 $(call if_changed_dep,cpp_s_S)
358
359quiet_cmd_as_o_S = AS $(quiet_modtag) $@
360
361ifndef CONFIG_MODVERSIONS
362cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
363
364else
365
366ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
367
368ifeq ($(ASM_PROTOTYPES),)
369cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
370
371else
372
373# versioning matches the C process described above, with difference that
374# we parse asm-prototypes.h C header to get function definitions.
375
376cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
377
378cmd_modversions_S = \
379 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
380 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
381 > $(@D)/.tmp_$(@F:.o=.ver); \
382 \
383 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
384 -T $(@D)/.tmp_$(@F:.o=.ver); \
385 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
386 else \
387 mv -f $(@D)/.tmp_$(@F) $@; \
388 fi;
389endif
390endif
391
392$(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE
393 $(call if_changed_rule,as_o_S)
394
395targets += $(real-objs-y) $(real-objs-m) $(lib-y)
396targets += $(extra-y) $(MAKECMDGOALS) $(always)
397
398# Linker scripts preprocessor (.lds.S -> .lds)
399# ---------------------------------------------------------------------------
400quiet_cmd_cpp_lds_S = LDS $@
401 cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
402 -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
403
404$(obj)/%.lds: $(src)/%.lds.S FORCE
405 $(call if_changed_dep,cpp_lds_S)
406
407# ASN.1 grammar
408# ---------------------------------------------------------------------------
409quiet_cmd_asn1_compiler = ASN.1 $@
410 cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
411 $(subst .h,.c,$@) $(subst .c,.h,$@)
412
413.PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
414
415$(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
416 $(call cmd,asn1_compiler)
417
418# Build the compiled-in targets
419# ---------------------------------------------------------------------------
420
421# To build objects in subdirs, we need to descend into the directories
422$(sort $(subdir-obj-y)): $(subdir-ym) ;
423
424#
425# Rule to compile a set of .o files into one .o file
426#
427ifdef builtin-target
428
429ifdef CONFIG_THIN_ARCHIVES
430 cmd_make_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
431 cmd_make_empty_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
432 quiet_cmd_link_o_target = AR $@
433else
434 cmd_make_builtin = $(LD) $(ld_flags) -r -o
435 cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS)
436 quiet_cmd_link_o_target = LD $@
437endif
438
439# If the list of objects to link is empty, just create an empty built-in.o
440cmd_link_o_target = $(if $(strip $(obj-y)),\
441 $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \
442 $(cmd_secanalysis),\
443 $(cmd_make_empty_builtin) $@)
444
445$(builtin-target): $(obj-y) FORCE
446 $(call if_changed,link_o_target)
447
448targets += $(builtin-target)
449endif # builtin-target
450
451#
452# Rule to create modules.order file
453#
454# Create commands to either record .ko file or cat modules.order from
455# a subdirectory
456modorder-cmds = \
457 $(foreach m, $(modorder), \
458 $(if $(filter %/modules.order, $m), \
459 cat $m;, echo kernel/$m;))
460
461$(modorder-target): $(subdir-ym) FORCE
462 $(Q)(cat /dev/null; $(modorder-cmds)) > $@
463
464#
465# Rule to compile a set of .o files into one .a file
466#
467ifdef lib-target
468quiet_cmd_link_l_target = AR $@
469
470ifdef CONFIG_THIN_ARCHIVES
471 cmd_link_l_target = rm -f $@; $(AR) rcsT$(KBUILD_ARFLAGS) $@ $(lib-y)
472else
473 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
474endif
475
476$(lib-target): $(lib-y) FORCE
477 $(call if_changed,link_l_target)
478
479targets += $(lib-target)
480
481dummy-object = $(obj)/.lib_exports.o
482ksyms-lds = $(dot-target).lds
483ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
484ref_prefix = EXTERN(_
485else
486ref_prefix = EXTERN(
487endif
488
489quiet_cmd_export_list = EXPORTS $@
490cmd_export_list = $(OBJDUMP) -h $< | \
491 sed -ne '/___ksymtab/{s/.*+/$(ref_prefix)/;s/ .*/)/;p}' >$(ksyms-lds);\
492 rm -f $(dummy-object);\
493 $(AR) rcs$(KBUILD_ARFLAGS) $(dummy-object);\
494 $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
495 rm $(dummy-object) $(ksyms-lds)
496
497$(obj)/lib-ksyms.o: $(lib-target) FORCE
498 $(call if_changed,export_list)
499
500targets += $(obj)/lib-ksyms.o
501
502endif
503
504#
505# Rule to link composite objects
506#
507# Composite objects are specified in kbuild makefile as follows:
508# <composite-object>-objs := <list of .o files>
509# or
510# <composite-object>-y := <list of .o files>
511# or
512# <composite-object>-m := <list of .o files>
513# The -m syntax only works if <composite object> is a module
514link_multi_deps = \
515$(filter $(addprefix $(obj)/, \
516$($(subst $(obj)/,,$(@:.o=-objs))) \
517$($(subst $(obj)/,,$(@:.o=-y))) \
518$($(subst $(obj)/,,$(@:.o=-m)))), $^)
519
520quiet_cmd_link_multi-y = LD $@
521cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
522
523quiet_cmd_link_multi-m = LD [M] $@
524cmd_link_multi-m = $(cmd_link_multi-y)
525
526$(multi-used-y): FORCE
527 $(call if_changed,link_multi-y)
528$(call multi_depend, $(multi-used-y), .o, -objs -y)
529
530$(multi-used-m): FORCE
531 $(call if_changed,link_multi-m)
532 @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
533 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
534$(call multi_depend, $(multi-used-m), .o, -objs -y -m)
535
536targets += $(multi-used-y) $(multi-used-m)
537
538
539# Descending
540# ---------------------------------------------------------------------------
541
542PHONY += $(subdir-ym)
543$(subdir-ym):
544 $(Q)$(MAKE) $(build)=$@
545
546# Add FORCE to the prequisites of a target to force it to be always rebuilt.
547# ---------------------------------------------------------------------------
548
549PHONY += FORCE
550
551FORCE:
552
553# Read all saved command lines and dependencies for the $(targets) we
554# may be building above, using $(if_changed{,_dep}). As an
555# optimization, we don't need to read them if the target does not
556# exist, we will rebuild anyway in that case.
557
558targets := $(wildcard $(sort $(targets)))
559cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
560
561ifneq ($(cmd_files),)
562 include $(cmd_files)
563endif
564
565# Declare the contents of the .PHONY variable as phony. We keep that
566# information in a variable se we can use it in if_changed and friends.
567
568.PHONY: $(PHONY)