module: Add retpoline tag to VERMAGIC
[sfrench/cifs-2.6.git] / scripts / Makefile.build
1 # SPDX-License-Identifier: GPL-2.0
2 # ==========================================================================
3 # Building
4 # ==========================================================================
5
6 src := $(obj)
7
8 PHONY := __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
14 obj-y :=
15 obj-m :=
16 lib-y :=
17 lib-m :=
18 always :=
19 targets :=
20 subdir-y :=
21 subdir-m :=
22 EXTRA_AFLAGS   :=
23 EXTRA_CFLAGS   :=
24 EXTRA_CPPFLAGS :=
25 EXTRA_LDFLAGS  :=
26 asflags-y  :=
27 ccflags-y  :=
28 cppflags-y :=
29 ldflags-y  :=
30
31 subdir-asflags-y :=
32 subdir-ccflags-y :=
33
34 # Read auto.conf if it exists, otherwise ignore
35 -include include/config/auto.conf
36
37 include scripts/Kbuild.include
38
39 # For backward compatibility check that these variables do not change
40 save-cflags := $(CFLAGS)
41
42 # The filename Kbuild has precedence over Makefile
43 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
44 kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
45 include $(kbuild-file)
46
47 # If the save-* variables changed error out
48 ifeq ($(KBUILD_NOPEDANTIC),)
49         ifneq ("$(save-cflags)","$(CFLAGS)")
50                 $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
51         endif
52 endif
53
54 include scripts/Makefile.lib
55
56 ifdef host-progs
57 ifneq ($(hostprogs-y),$(host-progs))
58 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
59 hostprogs-y += $(host-progs)
60 endif
61 endif
62
63 # Do not include host rules unless needed
64 ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
65 include scripts/Makefile.host
66 endif
67
68 ifneq ($(KBUILD_SRC),)
69 # Create output directory if not already present
70 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
71
72 # Create directories for object files if directory does not exist
73 # Needed when obj-y := dir/file.o syntax is used
74 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
75 endif
76
77 ifndef obj
78 $(warning kbuild: Makefile.build is included improperly)
79 endif
80
81 # ===========================================================================
82
83 ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
84 lib-target := $(obj)/lib.a
85 obj-y += $(obj)/lib-ksyms.o
86 endif
87
88 ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
89 builtin-target := $(obj)/built-in.o
90 endif
91
92 modorder-target := $(obj)/modules.order
93
94 # We keep a list of all modules in $(MODVERDIR)
95
96 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
97          $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
98          $(subdir-ym) $(always)
99         @:
100
101 # Linus' kernel sanity checking tool
102 ifneq ($(KBUILD_CHECKSRC),0)
103   ifeq ($(KBUILD_CHECKSRC),2)
104     quiet_cmd_force_checksrc = CHECK   $<
105           cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
106   else
107       quiet_cmd_checksrc     = CHECK   $<
108             cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
109   endif
110 endif
111
112 # Do section mismatch analysis for each module/built-in.o
113 ifdef CONFIG_DEBUG_SECTION_MISMATCH
114   cmd_secanalysis = ; scripts/mod/modpost $@
115 endif
116
117 # Compile C sources (.c)
118 # ---------------------------------------------------------------------------
119
120 # Default is built-in, unless we know otherwise
121 modkern_cflags =                                          \
122         $(if $(part-of-module),                           \
123                 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
124                 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
125 quiet_modtag := $(empty)   $(empty)
126
127 $(real-objs-m)        : part-of-module := y
128 $(real-objs-m:.o=.i)  : part-of-module := y
129 $(real-objs-m:.o=.s)  : part-of-module := y
130 $(real-objs-m:.o=.lst): part-of-module := y
131
132 $(real-objs-m)        : quiet_modtag := [M]
133 $(real-objs-m:.o=.i)  : quiet_modtag := [M]
134 $(real-objs-m:.o=.s)  : quiet_modtag := [M]
135 $(real-objs-m:.o=.lst): quiet_modtag := [M]
136
137 $(obj-m)              : quiet_modtag := [M]
138
139 # Default for not multi-part modules
140 modname = $(basetarget)
141
142 $(multi-objs-m)         : modname = $(modname-multi)
143 $(multi-objs-m:.o=.i)   : modname = $(modname-multi)
144 $(multi-objs-m:.o=.s)   : modname = $(modname-multi)
145 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
146 $(multi-objs-y)         : modname = $(modname-multi)
147 $(multi-objs-y:.o=.i)   : modname = $(modname-multi)
148 $(multi-objs-y:.o=.s)   : modname = $(modname-multi)
149 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
150
151 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
152 cmd_cc_s_c       = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
153
154 $(obj)/%.s: $(src)/%.c FORCE
155         $(call if_changed_dep,cc_s_c)
156
157 quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
158 cmd_cpp_i_c       = $(CPP) $(c_flags) -o $@ $<
159
160 $(obj)/%.i: $(src)/%.c FORCE
161         $(call if_changed_dep,cpp_i_c)
162
163 # These mirror gensymtypes_S and co below, keep them in synch.
164 cmd_gensymtypes_c =                                                         \
165     $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
166     $(GENKSYMS) $(if $(1), -T $(2))                                         \
167      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
168      $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
169      $(if $(KBUILD_PRESERVE),-p)                                            \
170      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
171
172 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
173 cmd_cc_symtypes_c =                                                         \
174     set -e;                                                                 \
175     $(call cmd_gensymtypes_c,true,$@) >/dev/null;                           \
176     test -s $@ || rm -f $@
177
178 $(obj)/%.symtypes : $(src)/%.c FORCE
179         $(call cmd,cc_symtypes_c)
180
181 # LLVM assembly
182 # Generate .ll files from .c
183 quiet_cmd_cc_ll_c = CC $(quiet_modtag)  $@
184       cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
185
186 $(obj)/%.ll: $(src)/%.c FORCE
187         $(call if_changed_dep,cc_ll_c)
188
189 # C (.c) files
190 # The C file is compiled and updated dependency information is generated.
191 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
192
193 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
194
195 ifndef CONFIG_MODVERSIONS
196 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
197
198 else
199 # When module versioning is enabled the following steps are executed:
200 # o compile a .tmp_<file>.o from <file>.c
201 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
202 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
203 #   are done.
204 # o otherwise, we calculate symbol versions using the good old
205 #   genksyms on the preprocessed source and postprocess them in a way
206 #   that they are usable as a linker script
207 # o generate <file>.o from .tmp_<file>.o using the linker to
208 #   replace the unresolved symbols __crc_exported_symbol with
209 #   the actual value of the checksum generated by genksyms
210
211 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
212
213 cmd_modversions_c =                                                             \
214         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
215                 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
216                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
217                                                                                 \
218                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
219                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
220                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
221         else                                                                    \
222                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
223         fi;
224 endif
225
226 ifdef CONFIG_FTRACE_MCOUNT_RECORD
227 ifdef BUILD_C_RECORDMCOUNT
228 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
229   RECORDMCOUNT_FLAGS = -w
230 endif
231 # Due to recursion, we must skip empty.o.
232 # The empty.o file is created in the make process in order to determine
233 # the target endianness and word size. It is made before all other C
234 # files, including recordmcount.
235 sub_cmd_record_mcount =                                 \
236         if [ $(@) != "scripts/mod/empty.o" ]; then      \
237                 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
238         fi;
239 recordmcount_source := $(srctree)/scripts/recordmcount.c \
240                     $(srctree)/scripts/recordmcount.h
241 else
242 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
243         "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
244         "$(if $(CONFIG_64BIT),64,32)" \
245         "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
246         "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
247         "$(if $(part-of-module),1,0)" "$(@)";
248 recordmcount_source := $(srctree)/scripts/recordmcount.pl
249 endif # BUILD_C_RECORDMCOUNT
250 cmd_record_mcount =                                             \
251         if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" =   \
252              "$(CC_FLAGS_FTRACE)" ]; then                       \
253                 $(sub_cmd_record_mcount)                        \
254         fi;
255 endif # CONFIG_FTRACE_MCOUNT_RECORD
256
257 ifdef CONFIG_STACK_VALIDATION
258 ifneq ($(SKIP_STACK_VALIDATION),1)
259
260 __objtool_obj := $(objtree)/tools/objtool/objtool
261
262 objtool_args = $(if $(CONFIG_UNWINDER_ORC),orc generate,check)
263
264 ifndef CONFIG_FRAME_POINTER
265 objtool_args += --no-fp
266 endif
267 ifdef CONFIG_GCOV_KERNEL
268 objtool_args += --no-unreachable
269 else
270 objtool_args += $(call cc-ifversion, -lt, 0405, --no-unreachable)
271 endif
272
273 ifdef CONFIG_MODVERSIONS
274 objtool_o = $(@D)/.tmp_$(@F)
275 else
276 objtool_o = $(@)
277 endif
278
279 # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
280 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
281 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
282 cmd_objtool = $(if $(patsubst y%,, \
283         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
284         $(__objtool_obj) $(objtool_args) "$(objtool_o)";)
285 objtool_obj = $(if $(patsubst y%,, \
286         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
287         $(__objtool_obj))
288
289 endif # SKIP_STACK_VALIDATION
290 endif # CONFIG_STACK_VALIDATION
291
292 # Rebuild all objects when objtool changes, or is enabled/disabled.
293 objtool_dep = $(objtool_obj)                                    \
294               $(wildcard include/config/orc/unwinder.h          \
295                          include/config/stack/validation.h)
296
297 define rule_cc_o_c
298         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
299         $(call cmd_and_fixdep,cc_o_c)                                     \
300         $(call echo-cmd,objtool) $(cmd_objtool)                           \
301         $(cmd_modversions_c)                                              \
302         $(call echo-cmd,record_mcount) $(cmd_record_mcount)
303 endef
304
305 define rule_as_o_S
306         $(call cmd_and_fixdep,as_o_S)                                     \
307         $(call echo-cmd,objtool) $(cmd_objtool)                           \
308         $(cmd_modversions_S)
309 endef
310
311 # List module undefined symbols (or empty line if not enabled)
312 ifdef CONFIG_TRIM_UNUSED_KSYMS
313 cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
314 else
315 cmd_undef_syms = echo
316 endif
317
318 # Built-in and composite module parts
319 $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
320         $(call cmd,force_checksrc)
321         $(call if_changed_rule,cc_o_c)
322
323 # Single-part modules are special since we need to mark them in $(MODVERDIR)
324
325 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
326         $(call cmd,force_checksrc)
327         $(call if_changed_rule,cc_o_c)
328         @{ echo $(@:.o=.ko); echo $@; \
329            $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
330
331 quiet_cmd_cc_lst_c = MKLST   $@
332       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
333                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
334                                      System.map $(OBJDUMP) > $@
335
336 $(obj)/%.lst: $(src)/%.c FORCE
337         $(call if_changed_dep,cc_lst_c)
338
339 # Compile assembler sources (.S)
340 # ---------------------------------------------------------------------------
341
342 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
343
344 $(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
345 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
346
347 # .S file exports must have their C prototypes defined in asm/asm-prototypes.h
348 # or a file that it includes, in order to get versioned symbols. We build a
349 # dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
350 # the .S file (with trailing ';'), and run genksyms on that, to extract vers.
351 #
352 # This is convoluted. The .S file must first be preprocessed to run guards and
353 # expand names, then the resulting exports must be constructed into plain
354 # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
355 # to make the genksyms input.
356 #
357 # These mirror gensymtypes_c and co above, keep them in synch.
358 cmd_gensymtypes_S =                                                         \
359     (echo "\#include <linux/kernel.h>" ;                                    \
360      echo "\#include <asm/asm-prototypes.h>" ;                              \
361     $(CPP) $(a_flags) $< |                                                  \
362      grep "\<___EXPORT_SYMBOL\>" |                                          \
363      sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
364     $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
365     $(GENKSYMS) $(if $(1), -T $(2))                                         \
366      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
367      $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
368      $(if $(KBUILD_PRESERVE),-p)                                            \
369      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
370
371 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
372 cmd_cc_symtypes_S =                                                         \
373     set -e;                                                                 \
374     $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
375     test -s $@ || rm -f $@
376
377 $(obj)/%.symtypes : $(src)/%.S FORCE
378         $(call cmd,cc_symtypes_S)
379
380
381 quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
382 cmd_cpp_s_S       = $(CPP) $(a_flags) -o $@ $<
383
384 $(obj)/%.s: $(src)/%.S FORCE
385         $(call if_changed_dep,cpp_s_S)
386
387 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
388
389 ifndef CONFIG_MODVERSIONS
390 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
391
392 else
393
394 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
395
396 ifeq ($(ASM_PROTOTYPES),)
397 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
398
399 else
400
401 # versioning matches the C process described above, with difference that
402 # we parse asm-prototypes.h C header to get function definitions.
403
404 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
405
406 cmd_modversions_S =                                                             \
407         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
408                 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
409                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
410                                                                                 \
411                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
412                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
413                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
414         else                                                                    \
415                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
416         fi;
417 endif
418 endif
419
420 $(obj)/%.o: $(src)/%.S $(objtool_dep) FORCE
421         $(call if_changed_rule,as_o_S)
422
423 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
424 targets += $(extra-y) $(MAKECMDGOALS) $(always)
425
426 # Linker scripts preprocessor (.lds.S -> .lds)
427 # ---------------------------------------------------------------------------
428 quiet_cmd_cpp_lds_S = LDS     $@
429       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -U$(ARCH) \
430                              -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
431
432 $(obj)/%.lds: $(src)/%.lds.S FORCE
433         $(call if_changed_dep,cpp_lds_S)
434
435 # ASN.1 grammar
436 # ---------------------------------------------------------------------------
437 quiet_cmd_asn1_compiler = ASN.1   $@
438       cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
439                                 $(subst .h,.c,$@) $(subst .c,.h,$@)
440
441 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
442
443 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
444         $(call cmd,asn1_compiler)
445
446 # Build the compiled-in targets
447 # ---------------------------------------------------------------------------
448
449 # To build objects in subdirs, we need to descend into the directories
450 $(sort $(subdir-obj-y)): $(subdir-ym) ;
451
452 #
453 # Rule to compile a set of .o files into one .o file
454 #
455 ifdef builtin-target
456
457 ifdef CONFIG_THIN_ARCHIVES
458   cmd_make_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS)
459   cmd_make_empty_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS)
460   quiet_cmd_link_o_target = AR      $@
461 else
462   cmd_make_builtin = $(LD) $(ld_flags) -r -o
463   cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS)
464   quiet_cmd_link_o_target = LD      $@
465 endif
466
467 # If the list of objects to link is empty, just create an empty built-in.o
468 cmd_link_o_target = $(if $(strip $(obj-y)),\
469                       $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \
470                       $(cmd_secanalysis),\
471                       $(cmd_make_empty_builtin) $@)
472
473 $(builtin-target): $(obj-y) FORCE
474         $(call if_changed,link_o_target)
475
476 targets += $(builtin-target)
477 endif # builtin-target
478
479 #
480 # Rule to create modules.order file
481 #
482 # Create commands to either record .ko file or cat modules.order from
483 # a subdirectory
484 modorder-cmds =                                         \
485         $(foreach m, $(modorder),                       \
486                 $(if $(filter %/modules.order, $m),     \
487                         cat $m;, echo kernel/$m;))
488
489 $(modorder-target): $(subdir-ym) FORCE
490         $(Q)(cat /dev/null; $(modorder-cmds)) > $@
491
492 #
493 # Rule to compile a set of .o files into one .a file
494 #
495 ifdef lib-target
496 quiet_cmd_link_l_target = AR      $@
497
498 ifdef CONFIG_THIN_ARCHIVES
499   cmd_link_l_target = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(lib-y)
500 else
501   cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
502 endif
503
504 $(lib-target): $(lib-y) FORCE
505         $(call if_changed,link_l_target)
506
507 targets += $(lib-target)
508
509 dummy-object = $(obj)/.lib_exports.o
510 ksyms-lds = $(dot-target).lds
511 ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
512 ref_prefix = EXTERN(_
513 else
514 ref_prefix = EXTERN(
515 endif
516
517 quiet_cmd_export_list = EXPORTS $@
518 cmd_export_list = $(OBJDUMP) -h $< | \
519         sed -ne '/___ksymtab/s/.*+\([^ ]*\).*/$(ref_prefix)\1)/p' >$(ksyms-lds);\
520         rm -f $(dummy-object);\
521         echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\
522         $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
523         rm $(dummy-object) $(ksyms-lds)
524
525 $(obj)/lib-ksyms.o: $(lib-target) FORCE
526         $(call if_changed,export_list)
527
528 targets += $(obj)/lib-ksyms.o
529
530 endif
531
532 #
533 # Rule to link composite objects
534 #
535 #  Composite objects are specified in kbuild makefile as follows:
536 #    <composite-object>-objs := <list of .o files>
537 #  or
538 #    <composite-object>-y    := <list of .o files>
539 #  or
540 #    <composite-object>-m    := <list of .o files>
541 #  The -m syntax only works if <composite object> is a module
542 link_multi_deps =                     \
543 $(filter $(addprefix $(obj)/,         \
544 $($(subst $(obj)/,,$(@:.o=-objs)))    \
545 $($(subst $(obj)/,,$(@:.o=-y)))       \
546 $($(subst $(obj)/,,$(@:.o=-m)))), $^)
547
548 cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
549
550 ifdef CONFIG_THIN_ARCHIVES
551   quiet_cmd_link_multi-y = AR      $@
552   cmd_link_multi-y = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) $@ $(link_multi_deps)
553 else
554   quiet_cmd_link_multi-y = LD      $@
555   cmd_link_multi-y = $(cmd_link_multi-link)
556 endif
557
558 quiet_cmd_link_multi-m = LD [M]  $@
559 cmd_link_multi-m = $(cmd_link_multi-link)
560
561 $(multi-used-y): FORCE
562         $(call if_changed,link_multi-y)
563 $(call multi_depend, $(multi-used-y), .o, -objs -y)
564
565 $(multi-used-m): FORCE
566         $(call if_changed,link_multi-m)
567         @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
568            $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
569 $(call multi_depend, $(multi-used-m), .o, -objs -y -m)
570
571 targets += $(multi-used-y) $(multi-used-m)
572
573
574 # Descending
575 # ---------------------------------------------------------------------------
576
577 PHONY += $(subdir-ym)
578 $(subdir-ym):
579         $(Q)$(MAKE) $(build)=$@
580
581 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
582 # ---------------------------------------------------------------------------
583
584 PHONY += FORCE
585
586 FORCE:
587
588 # Read all saved command lines and dependencies for the $(targets) we
589 # may be building above, using $(if_changed{,_dep}). As an
590 # optimization, we don't need to read them if the target does not
591 # exist, we will rebuild anyway in that case.
592
593 targets := $(wildcard $(sort $(targets)))
594 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
595
596 ifneq ($(cmd_files),)
597   include $(cmd_files)
598 endif
599
600 # Declare the contents of the .PHONY variable as phony.  We keep that
601 # information in a variable se we can use it in if_changed and friends.
602
603 .PHONY: $(PHONY)