scripts/Makefile.build

   1 # ==========================================================================
   2 # Building
   3 # ==========================================================================
   4
   5 src := $(obj)
   6
   7 PHONY := __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
  13 obj-y :=
  14 obj-m :=
  15 lib-y :=
  16 lib-m :=
  17 always :=
  18 targets :=
  19 subdir-y :=
  20 subdir-m :=
  21 EXTRA_AFLAGS   :=
  22 EXTRA_CFLAGS   :=
  23 EXTRA_CPPFLAGS :=
  24 EXTRA_LDFLAGS  :=
  25 asflags-y  :=
  26 ccflags-y  :=
  27 cppflags-y :=
  28 ldflags-y  :=
  29
  30 subdir-asflags-y :=
  31 subdir-ccflags-y :=
  32
  33 # Read auto.conf if it exists, otherwise ignore
  34 -include include/config/auto.conf
  35
  36 include scripts/Kbuild.include
  37
  38 # For backward compatibility check that these variables do not change
  39 save-cflags := $(CFLAGS)
  40
  41 # The filename Kbuild has precedence over Makefile
  42 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
  43 kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
  44 include $(kbuild-file)
  45
  46 # If the save-* variables changed error out
  47 ifeq ($(KBUILD_NOPEDANTIC),)
  48         ifneq ("$(save-cflags)","$(CFLAGS)")
  49                 $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
  50         endif
  51 endif
  52
  53 include scripts/Makefile.lib
  54
  55 ifdef host-progs
  56 ifneq ($(hostprogs-y),$(host-progs))
  57 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
  58 hostprogs-y += $(host-progs)
  59 endif
  60 endif
  61
  62 # Do not include host rules unless needed
  63 ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
  64 include scripts/Makefile.host
  65 endif
  66
  67 ifneq ($(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)))
  74 endif
  75
  76 ifndef obj
  77 $(warning kbuild: Makefile.build is included improperly)
  78 endif
  79
  80 # ===========================================================================
  81
  82 ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
  83 lib-target := $(obj)/lib.a
  84 obj-y += $(obj)/lib-ksyms.o
  85 endif
  86
  87 ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
  88 builtin-target := $(obj)/built-in.o
  89 endif
  90
  91 modorder-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) $(always)
  98         @:
  99
 100 # Linus' kernel sanity checking tool
 101 ifneq ($(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
 109 endif
 110
 111 # Do section mismatch analysis for each module/built-in.o
 112 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 113   cmd_secanalysis = ; scripts/mod/modpost $@
 114 endif
 115
 116 # Compile C sources (.c)
 117 # ---------------------------------------------------------------------------
 118
 119 # Default is built-in, unless we know otherwise
 120 modkern_cflags =                                          \
 121         $(if $(part-of-module),                           \
 122                 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 123                 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
 124 quiet_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
 139 modname = $(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
 150 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
 151 cmd_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
 156 quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
 157 cmd_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.
 163 cmd_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
 170 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 171 cmd_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
 183 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 184
 185 ifndef CONFIG_MODVERSIONS
 186 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 187
 188 else
 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
 201 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 202
 203 cmd_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) $@;                                      \
 213         fi;
 214 endif
 215
 216 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 217 ifdef BUILD_C_RECORDMCOUNT
 218 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
 219   RECORDMCOUNT_FLAGS = -w
 220 endif
 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.
 225 sub_cmd_record_mcount =                                 \
 226         if [ $(@) != "scripts/mod/empty.o" ]; then      \
 227                 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
 228         fi;
 229 recordmcount_source := $(srctree)/scripts/recordmcount.c \
 230                     $(srctree)/scripts/recordmcount.h
 231 else
 232 sub_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 $(part-of-module),1,0)" "$(@)";
 238 recordmcount_source := $(srctree)/scripts/recordmcount.pl
 239 endif
 240 cmd_record_mcount =                                             \
 241         if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" =   \
 242              "$(CC_FLAGS_FTRACE)" ]; then                       \
 243                 $(sub_cmd_record_mcount)                        \
 244         fi;
 245 endif
 246
 247 ifdef CONFIG_STACK_VALIDATION
 248 ifneq ($(SKIP_STACK_VALIDATION),1)
 249
 250 __objtool_obj := $(objtree)/tools/objtool/objtool
 251
 252 objtool_args = check
 253 ifndef CONFIG_FRAME_POINTER
 254 objtool_args += --no-fp
 255 endif
 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
 260 cmd_objtool = $(if $(patsubst y%,, \
 261         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
 262         $(__objtool_obj) $(objtool_args) "$(@)";)
 263 objtool_obj = $(if $(patsubst y%,, \
 264         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
 265         $(__objtool_obj))
 266
 267 endif # SKIP_STACK_VALIDATION
 268 endif # CONFIG_STACK_VALIDATION
 269
 270 define 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)
 276 endef
 277
 278 define rule_as_o_S
 279         $(call cmd_and_fixdep,as_o_S)                                     \
 280         $(cmd_modversions_S)                                              \
 281         $(cmd_objtool)
 282 endef
 283
 284 # List module undefined symbols (or empty line if not enabled)
 285 ifdef CONFIG_TRIM_UNUSED_KSYMS
 286 cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
 287 else
 288 cmd_undef_syms = echo
 289 endif
 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
 304 quiet_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
 315 modkern_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.
 331 cmd_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
 343 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
 344 cmd_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
 353 quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
 354 cmd_cpp_s_S       = $(CPP) $(a_flags) -o $@ $<
 355
 356 $(obj)/%.s: $(src)/%.S FORCE
 357         $(call if_changed_dep,cpp_s_S)
 358
 359 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 360
 361 ifndef CONFIG_MODVERSIONS
 362 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 363
 364 else
 365
 366 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
 367
 368 ifeq ($(ASM_PROTOTYPES),)
 369 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 370
 371 else
 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
 376 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
 377
 378 cmd_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;
 389 endif
 390 endif
 391
 392 $(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE
 393         $(call if_changed_rule,as_o_S)
 394
 395 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 396 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 397
 398 # Linker scripts preprocessor (.lds.S -> .lds)
 399 # ---------------------------------------------------------------------------
 400 quiet_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 # ---------------------------------------------------------------------------
 409 quiet_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 #
 427 ifdef builtin-target
 428
 429 ifdef 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      $@
 433 else
 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      $@
 437 endif
 438
 439 # If the list of objects to link is empty, just create an empty built-in.o
 440 cmd_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
 448 targets += $(builtin-target)
 449 endif # 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
 456 modorder-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 #
 467 ifdef lib-target
 468 quiet_cmd_link_l_target = AR      $@
 469
 470 ifdef CONFIG_THIN_ARCHIVES
 471   cmd_link_l_target = rm -f $@; $(AR) rcsT$(KBUILD_ARFLAGS) $@ $(lib-y)
 472 else
 473   cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
 474 endif
 475
 476 $(lib-target): $(lib-y) FORCE
 477         $(call if_changed,link_l_target)
 478
 479 targets += $(lib-target)
 480
 481 dummy-object = $(obj)/.lib_exports.o
 482 ksyms-lds = $(dot-target).lds
 483 ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
 484 ref_prefix = EXTERN(_
 485 else
 486 ref_prefix = EXTERN(
 487 endif
 488
 489 quiet_cmd_export_list = EXPORTS $@
 490 cmd_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
 500 targets += $(obj)/lib-ksyms.o
 501
 502 endif
 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
 514 link_multi_deps =                     \
 515 $(filter $(addprefix $(obj)/,         \
 516 $($(subst $(obj)/,,$(@:.o=-objs)))    \
 517 $($(subst $(obj)/,,$(@:.o=-y)))       \
 518 $($(subst $(obj)/,,$(@:.o=-m)))), $^)
 519
 520 quiet_cmd_link_multi-y = LD      $@
 521 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
 522
 523 quiet_cmd_link_multi-m = LD [M]  $@
 524 cmd_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
 536 targets += $(multi-used-y) $(multi-used-m)
 537
 538
 539 # Descending
 540 # ---------------------------------------------------------------------------
 541
 542 PHONY += $(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
 549 PHONY += FORCE
 550
 551 FORCE:
 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
 558 targets := $(wildcard $(sort $(targets)))
 559 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 560
 561 ifneq ($(cmd_files),)
 562   include $(cmd_files)
 563 endif
 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)