summaryrefslogtreecommitdiffstats
path: root/scripts/Makefile.build
blob: 061d0c3a420ad58084df157a143e76133f304dc2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
# ==========================================================================
# Building
# ==========================================================================

src := $(obj)

PHONY := __build
__build:

# Init all relevant variables used in kbuild files so
# 1) they have correct type
# 2) they do not inherit any value from the environment
obj-y :=
obj-m :=
lib-y :=
lib-m :=
always :=
targets :=
subdir-y :=
subdir-m :=
EXTRA_AFLAGS   :=
EXTRA_CFLAGS   :=
EXTRA_CPPFLAGS :=
EXTRA_LDFLAGS  :=
asflags-y  :=
ccflags-y  :=
cppflags-y :=
ldflags-y  :=

subdir-asflags-y :=
subdir-ccflags-y :=

# Read auto.conf if it exists, otherwise ignore
-include include/config/auto.conf

include scripts/Kbuild.include

# For backward compatibility check that these variables do not change
save-cflags := $(CFLAGS)

# The filename Kbuild has precedence over Makefile
kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
include $(kbuild-file)

# If the save-* variables changed error out
ifeq ($(KBUILD_NOPEDANTIC),)
        ifneq ("$(save-cflags)","$(CFLAGS)")
                $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
        endif
endif

include scripts/Makefile.lib

ifdef host-progs
ifneq ($(hostprogs-y),$(host-progs))
$(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
hostprogs-y += $(host-progs)
endif
endif

# Do not include host rules unless needed
ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
include scripts/Makefile.host
endif

ifneq ($(KBUILD_SRC),)
# Create output directory if not already present
_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))

# Create directories for object files if directory does not exist
# Needed when obj-y := dir/file.o syntax is used
_dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
endif

ifndef obj
$(warning kbuild: Makefile.build is included improperly)
endif

# ===========================================================================

ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
lib-target := $(obj)/lib.a
obj-y += $(obj)/lib-ksyms.o
endif

ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
builtin-target := $(obj)/built-in.o
endif

modorder-target := $(obj)/modules.order

# We keep a list of all modules in $(MODVERDIR)

__build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
	 $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
	 $(subdir-ym) $(always)
	@:

# Linus' kernel sanity checking tool
ifneq ($(KBUILD_CHECKSRC),0)
  ifeq ($(KBUILD_CHECKSRC),2)
    quiet_cmd_force_checksrc = CHECK   $<
          cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
  else
      quiet_cmd_checksrc     = CHECK   $<
            cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
  endif
endif

# Do section mismatch analysis for each module/built-in.o
ifdef CONFIG_DEBUG_SECTION_MISMATCH
  cmd_secanalysis = ; scripts/mod/modpost $@
endif

# Compile C sources (.c)
# ---------------------------------------------------------------------------

# Default is built-in, unless we know otherwise
modkern_cflags =                                          \
	$(if $(part-of-module),                           \
		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
quiet_modtag := $(empty)   $(empty)

$(real-objs-m)        : part-of-module := y
$(real-objs-m:.o=.i)  : part-of-module := y
$(real-objs-m:.o=.s)  : part-of-module := y
$(real-objs-m:.o=.lst): part-of-module := y

$(real-objs-m)        : quiet_modtag := [M]
$(real-objs-m:.o=.i)  : quiet_modtag := [M]
$(real-objs-m:.o=.s)  : quiet_modtag := [M]
$(real-objs-m:.o=.lst): quiet_modtag := [M]

$(obj-m)              : quiet_modtag := [M]

# Default for not multi-part modules
modname = $(basetarget)

$(multi-objs-m)         : modname = $(modname-multi)
$(multi-objs-m:.o=.i)   : modname = $(modname-multi)
$(multi-objs-m:.o=.s)   : modname = $(modname-multi)
$(multi-objs-m:.o=.lst) : modname = $(modname-multi)
$(multi-objs-y)         : modname = $(modname-multi)
$(multi-objs-y:.o=.i)   : modname = $(modname-multi)
$(multi-objs-y:.o=.s)   : modname = $(modname-multi)
$(multi-objs-y:.o=.lst) : modname = $(modname-multi)

quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
cmd_cc_s_c       = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<

$(obj)/%.s: $(src)/%.c FORCE
	$(call if_changed_dep,cc_s_c)

quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
cmd_cpp_i_c       = $(CPP) $(c_flags) -o $@ $<

$(obj)/%.i: $(src)/%.c FORCE
	$(call if_changed_dep,cpp_i_c)

# These mirror gensymtypes_S and co below, keep them in synch.
cmd_gensymtypes_c =                                                         \
    $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
    $(GENKSYMS) $(if $(1), -T $(2))                                         \
     $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
     $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
     $(if $(KBUILD_PRESERVE),-p)                                            \
     -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))

quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
cmd_cc_symtypes_c =                                                         \
    set -e;                                                                 \
    $(call cmd_gensymtypes_c,true,$@) >/dev/null;                           \
    test -s $@ || rm -f $@

$(obj)/%.symtypes : $(src)/%.c FORCE
	$(call cmd,cc_symtypes_c)

# LLVM assembly
# Generate .ll files from .c
quiet_cmd_cc_ll_c = CC $(quiet_modtag)  $@
      cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<

$(obj)/%.ll: $(src)/%.c FORCE
	$(call if_changed_dep,cc_ll_c)

# C (.c) files
# The C file is compiled and updated dependency information is generated.
# (See cmd_cc_o_c + relevant part of rule_cc_o_c)

quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@

ifndef CONFIG_MODVERSIONS
cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<

else
# When module versioning is enabled the following steps are executed:
# o compile a .tmp_<file>.o from <file>.c
# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
#   not export symbols, we just rename .tmp_<file>.o to <file>.o and
#   are done.
# o otherwise, we calculate symbol versions using the good old
#   genksyms on the preprocessed source and postprocess them in a way
#   that they are usable as a linker script
# o generate <file>.o from .tmp_<file>.o using the linker to
#   replace the unresolved symbols __crc_exported_symbol with
#   the actual value of the checksum generated by genksyms

cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<

cmd_modversions_c =								\
	if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then		\
		$(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
		    > $(@D)/.tmp_$(@F:.o=.ver);					\
										\
		$(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) 			\
			-T $(@D)/.tmp_$(@F:.o=.ver);				\
		rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);		\
	else									\
		mv -f $(@D)/.tmp_$(@F) $@;					\
	fi;
endif

ifdef CONFIG_FTRACE_MCOUNT_RECORD
ifdef BUILD_C_RECORDMCOUNT
ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
  RECORDMCOUNT_FLAGS = -w
endif
# Due to recursion, we must skip empty.o.
# The empty.o file is created in the make process in order to determine
# the target endianness and word size. It is made before all other C
# files, including recordmcount.
sub_cmd_record_mcount =					\
	if [ $(@) != "scripts/mod/empty.o" ]; then	\
		$(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";	\
	fi;
recordmcount_source := $(srctree)/scripts/recordmcount.c \
		    $(srctree)/scripts/recordmcount.h
else
sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
	"$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
	"$(if $(CONFIG_64BIT),64,32)" \
	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
	"$(LD)" "$(NM)" "$(RM)" "$(MV)" \
	"$(if $(part-of-module),1,0)" "$(@)";
recordmcount_source := $(srctree)/scripts/recordmcount.pl
endif # BUILD_C_RECORDMCOUNT
cmd_record_mcount =						\
	if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" =	\
	     "$(CC_FLAGS_FTRACE)" ]; then			\
		$(sub_cmd_record_mcount)			\
	fi;
endif # CONFIG_FTRACE_MCOUNT_RECORD

ifdef CONFIG_STACK_VALIDATION
ifneq ($(SKIP_STACK_VALIDATION),1)

__objtool_obj := $(objtree)/tools/objtool/objtool

objtool_args = $(if $(CONFIG_ORC_UNWINDER),orc generate,check)

ifndef CONFIG_FRAME_POINTER
objtool_args += --no-fp
endif
ifdef CONFIG_GCOV_KERNEL
objtool_args += --no-unreachable
else
objtool_args += $(call cc-ifversion, -lt, 0405, --no-unreachable)
endif

# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
cmd_objtool = $(if $(patsubst y%,, \
	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
	$(__objtool_obj) $(objtool_args) "$(@)";)
objtool_obj = $(if $(patsubst y%,, \
	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
	$(__objtool_obj))

endif # SKIP_STACK_VALIDATION
endif # CONFIG_STACK_VALIDATION

# Rebuild all objects when objtool changes, or is enabled/disabled.
objtool_dep = $(objtool_obj)					\
	      $(wildcard include/config/orc/unwinder.h		\
			 include/config/stack/validation.h)

define rule_cc_o_c
	$(call echo-cmd,checksrc) $(cmd_checksrc)			  \
	$(call cmd_and_fixdep,cc_o_c)					  \
	$(cmd_modversions_c)						  \
	$(call echo-cmd,objtool) $(cmd_objtool)				  \
	$(call echo-cmd,record_mcount) $(cmd_record_mcount)
endef

define rule_as_o_S
	$(call cmd_and_fixdep,as_o_S)					  \
	$(cmd_modversions_S)						  \
	$(call echo-cmd,objtool) $(cmd_objtool)
endef

# List module undefined symbols (or empty line if not enabled)
ifdef CONFIG_TRIM_UNUSED_KSYMS
cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
else
cmd_undef_syms = echo
endif

# Built-in and composite module parts
$(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
	$(call cmd,force_checksrc)
	$(call if_changed_rule,cc_o_c)

# Single-part modules are special since we need to mark them in $(MODVERDIR)

$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
	$(call cmd,force_checksrc)
	$(call if_changed_rule,cc_o_c)
	@{ echo $(@:.o=.ko); echo $@; \
	   $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)

quiet_cmd_cc_lst_c = MKLST   $@
      cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
		     $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
				     System.map $(OBJDUMP) > $@

$(obj)/%.lst: $(src)/%.c FORCE
	$(call if_changed_dep,cc_lst_c)

# Compile assembler sources (.S)
# ---------------------------------------------------------------------------

modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)

$(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
$(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)

# .S file exports must have their C prototypes defined in asm/asm-prototypes.h
# or a file that it includes, in order to get versioned symbols. We build a
# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
# the .S file (with trailing ';'), and run genksyms on that, to extract vers.
#
# This is convoluted. The .S file must first be preprocessed to run guards and
# expand names, then the resulting exports must be constructed into plain
# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
# to make the genksyms input.
#
# These mirror gensymtypes_c and co above, keep them in synch.
cmd_gensymtypes_S =                                                         \
    (echo "\#include <linux/kernel.h>" ;                                    \
     echo "\#include <asm/asm-prototypes.h>" ;                              \
    $(CPP) $(a_flags) $< |                                                  \
     grep "\<___EXPORT_SYMBOL\>" |                                          \
     sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
    $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
    $(GENKSYMS) $(if $(1), -T $(2))                                         \
     $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
     $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
     $(if $(KBUILD_PRESERVE),-p)                                            \
     -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))

quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
cmd_cc_symtypes_S =                                                         \
    set -e;                                                                 \
    $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
    test -s $@ || rm -f $@

$(obj)/%.symtypes : $(src)/%.S FORCE
	$(call cmd,cc_symtypes_S)


quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
cmd_cpp_s_S       = $(CPP) $(a_flags) -o $@ $<

$(obj)/%.s: $(src)/%.S FORCE
	$(call if_changed_dep,cpp_s_S)

quiet_cmd_as_o_S = AS $(quiet_modtag)  $@

ifndef CONFIG_MODVERSIONS
cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<

else

ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)

ifeq ($(ASM_PROTOTYPES),)
cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<

else

# versioning matches the C process described above, with difference that
# we parse asm-prototypes.h C header to get function definitions.

cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<

cmd_modversions_S =								\
	if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then		\
		$(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
		    > $(@D)/.tmp_$(@F:.o=.ver);					\
										\
		$(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) 			\
			-T $(@D)/.tmp_$(@F:.o=.ver);				\
		rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);		\
	else									\
		mv -f $(@D)/.tmp_$(@F) $@;					\
	fi;
endif
endif

$(obj)/%.o: $(src)/%.S $(objtool_dep) FORCE
	$(call if_changed_rule,as_o_S)

targets += $(real-objs-y) $(real-objs-m) $(lib-y)
targets += $(extra-y) $(MAKECMDGOALS) $(always)

# Linker scripts preprocessor (.lds.S -> .lds)
# ---------------------------------------------------------------------------
quiet_cmd_cpp_lds_S = LDS     $@
      cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
	                     -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<

$(obj)/%.lds: $(src)/%.lds.S FORCE
	$(call if_changed_dep,cpp_lds_S)

# ASN.1 grammar
# ---------------------------------------------------------------------------
quiet_cmd_asn1_compiler = ASN.1   $@
      cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
				$(subst .h,.c,$@) $(subst .c,.h,$@)

.PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h

$(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
	$(call cmd,asn1_compiler)

# Build the compiled-in targets
# ---------------------------------------------------------------------------

# To build objects in subdirs, we need to descend into the directories
$(sort $(subdir-obj-y)): $(subdir-ym) ;

#
# Rule to compile a set of .o files into one .o file
#
ifdef builtin-target

ifdef CONFIG_THIN_ARCHIVES
  cmd_make_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS)
  cmd_make_empty_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS)
  quiet_cmd_link_o_target = AR      $@
else
  cmd_make_builtin = $(LD) $(ld_flags) -r -o
  cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS)
  quiet_cmd_link_o_target = LD      $@
endif

# If the list of objects to link is empty, just create an empty built-in.o
cmd_link_o_target = $(if $(strip $(obj-y)),\
		      $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \
		      $(cmd_secanalysis),\
		      $(cmd_make_empty_builtin) $@)

$(builtin-target): $(obj-y) FORCE
	$(call if_changed,link_o_target)

targets += $(builtin-target)
endif # builtin-target

#
# Rule to create modules.order file
#
# Create commands to either record .ko file or cat modules.order from
# a subdirectory
modorder-cmds =						\
	$(foreach m, $(modorder),			\
		$(if $(filter %/modules.order, $m),	\
			cat $m;, echo kernel/$m;))

$(modorder-target): $(subdir-ym) FORCE
	$(Q)(cat /dev/null; $(modorder-cmds)) > $@

#
# Rule to compile a set of .o files into one .a file
#
ifdef lib-target
quiet_cmd_link_l_target = AR      $@

ifdef CONFIG_THIN_ARCHIVES
  cmd_link_l_target = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(lib-y)
else
  cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
endif

$(lib-target): $(lib-y) FORCE
	$(call if_changed,link_l_target)

targets += $(lib-target)

dummy-object = $(obj)/.lib_exports.o
ksyms-lds = $(dot-target).lds
ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
ref_prefix = EXTERN(_
else
ref_prefix = EXTERN(
endif

quiet_cmd_export_list = EXPORTS $@
cmd_export_list = $(OBJDUMP) -h $< | \
	sed -ne '/___ksymtab/s/.*+\([^ ]*\).*/$(ref_prefix)\1)/p' >$(ksyms-lds);\
	rm -f $(dummy-object);\
	echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\
	$(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
	rm $(dummy-object) $(ksyms-lds)

$(obj)/lib-ksyms.o: $(lib-target) FORCE
	$(call if_changed,export_list)

targets += $(obj)/lib-ksyms.o

endif

#
# Rule to link composite objects
#
#  Composite objects are specified in kbuild makefile as follows:
#    <composite-object>-objs := <list of .o files>
#  or
#    <composite-object>-y    := <list of .o files>
#  or
#    <composite-object>-m    := <list of .o files>
#  The -m syntax only works if <composite object> is a module
link_multi_deps =                     \
$(filter $(addprefix $(obj)/,         \
$($(subst $(obj)/,,$(@:.o=-objs)))    \
$($(subst $(obj)/,,$(@:.o=-y)))       \
$($(subst $(obj)/,,$(@:.o=-m)))), $^)

cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)

ifdef CONFIG_THIN_ARCHIVES
  quiet_cmd_link_multi-y = AR      $@
  cmd_link_multi-y = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) $@ $(link_multi_deps)
else
  quiet_cmd_link_multi-y = LD      $@
  cmd_link_multi-y = $(cmd_link_multi-link)
endif

quiet_cmd_link_multi-m = LD [M]  $@
cmd_link_multi-m = $(cmd_link_multi-link)

$(multi-used-y): FORCE
	$(call if_changed,link_multi-y)
$(call multi_depend, $(multi-used-y), .o, -objs -y)

$(multi-used-m): FORCE
	$(call if_changed,link_multi-m)
	@{ echo $(@:.o=.ko); echo $(link_multi_deps); \
	   $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
$(call multi_depend, $(multi-used-m), .o, -objs -y -m)

targets += $(multi-used-y) $(multi-used-m)


# Descending
# ---------------------------------------------------------------------------

PHONY += $(subdir-ym)
$(subdir-ym):
	$(Q)$(MAKE) $(build)=$@

# Add FORCE to the prequisites of a target to force it to be always rebuilt.
# ---------------------------------------------------------------------------

PHONY += FORCE

FORCE:

# Read all saved command lines and dependencies for the $(targets) we
# may be building above, using $(if_changed{,_dep}). As an
# optimization, we don't need to read them if the target does not
# exist, we will rebuild anyway in that case.

targets := $(wildcard $(sort $(targets)))
cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))

ifneq ($(cmd_files),)
  include $(cmd_files)
endif

# Declare the contents of the .PHONY variable as phony.  We keep that
# information in a variable se we can use it in if_changed and friends.

.PHONY: $(PHONY)