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 # LLVM assembly
 180 # Generate .ll files from .c
 181 quiet_cmd_cc_ll_c = CC $(quiet_modtag)  $@
 182       cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
 183
 184 $(obj)/%.ll: $(src)/%.c FORCE
 185         $(call if_changed_dep,cc_ll_c)
 186
 187 # C (.c) files
 188 # The C file is compiled and updated dependency information is generated.
 189 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 190
 191 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 192
 193 ifndef CONFIG_MODVERSIONS
 194 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 195
 196 else
 197 # When module versioning is enabled the following steps are executed:
 198 # o compile a .tmp_<file>.o from <file>.c
 199 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
 200 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
 201 #   are done.
 202 # o otherwise, we calculate symbol versions using the good old
 203 #   genksyms on the preprocessed source and postprocess them in a way
 204 #   that they are usable as a linker script
 205 # o generate <file>.o from .tmp_<file>.o using the linker to
 206 #   replace the unresolved symbols __crc_exported_symbol with
 207 #   the actual value of the checksum generated by genksyms
 208
 209 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 210
 211 cmd_modversions_c =                                                             \
 212         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 213                 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
 214                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 215                                                                                 \
 216                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 217                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 218                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 219         else                                                                    \
 220                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 221         fi;
 222 endif
 223
 224 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 225 ifndef CC_USING_RECORD_MCOUNT
 226 # compiler will not generate __mcount_loc use recordmcount or recordmcount.pl
 227 ifdef BUILD_C_RECORDMCOUNT
 228 ifeq ("$(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 := $(srctree)/scripts/recordmcount.pl
 249 endif
 250 cmd_record_mcount =                                             \
 251         if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" =   \
 252              "$(CC_FLAGS_FTRACE)" ]; then                       \
 253                 $(sub_cmd_record_mcount)                        \
 254         fi;
 255 endif # CC_USING_RECORD_MCOUNT
 256 endif
 257
 258 ifdef CONFIG_STACK_VALIDATION
 259 ifneq ($(SKIP_STACK_VALIDATION),1)
 260
 261 __objtool_obj := $(objtree)/tools/objtool/objtool
 262
 263 objtool_args = check
 264 ifndef CONFIG_FRAME_POINTER
 265 objtool_args += --no-fp
 266 endif
 267 ifdef CONFIG_GCOV_KERNEL
 268 objtool_args += --no-unreachable
 269 endif
 270
 271 # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
 272 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
 273 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
 274 cmd_objtool = $(if $(patsubst y%,, \
 275         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
 276         $(__objtool_obj) $(objtool_args) "$(@)";)
 277 objtool_obj = $(if $(patsubst y%,, \
 278         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
 279         $(__objtool_obj))
 280
 281 endif # SKIP_STACK_VALIDATION
 282 endif # CONFIG_STACK_VALIDATION
 283
 284 define rule_cc_o_c
 285         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
 286         $(call cmd_and_fixdep,cc_o_c)                                     \
 287         $(cmd_modversions_c)                                              \
 288         $(cmd_objtool)                                                    \
 289         $(call echo-cmd,record_mcount) $(cmd_record_mcount)
 290 endef
 291
 292 define rule_as_o_S
 293         $(call cmd_and_fixdep,as_o_S)                                     \
 294         $(cmd_modversions_S)                                              \
 295         $(cmd_objtool)
 296 endef
 297
 298 # List module undefined symbols (or empty line if not enabled)
 299 ifdef CONFIG_TRIM_UNUSED_KSYMS
 300 cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
 301 else
 302 cmd_undef_syms = echo
 303 endif
 304
 305 # Built-in and composite module parts
 306 $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
 307         $(call cmd,force_checksrc)
 308         $(call if_changed_rule,cc_o_c)
 309
 310 # Single-part modules are special since we need to mark them in $(MODVERDIR)
 311
 312 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
 313         $(call cmd,force_checksrc)
 314         $(call if_changed_rule,cc_o_c)
 315         @{ echo $(@:.o=.ko); echo $@; \
 316            $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
 317
 318 quiet_cmd_cc_lst_c = MKLST   $@
 319       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
 320                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
 321                                      System.map $(OBJDUMP) > $@
 322
 323 $(obj)/%.lst: $(src)/%.c FORCE
 324         $(call if_changed_dep,cc_lst_c)
 325
 326 # Compile assembler sources (.S)
 327 # ---------------------------------------------------------------------------
 328
 329 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
 330
 331 $(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 332 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 333
 334 # .S file exports must have their C prototypes defined in asm/asm-prototypes.h
 335 # or a file that it includes, in order to get versioned symbols. We build a
 336 # dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
 337 # the .S file (with trailing ';'), and run genksyms on that, to extract vers.
 338 #
 339 # This is convoluted. The .S file must first be preprocessed to run guards and
 340 # expand names, then the resulting exports must be constructed into plain
 341 # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
 342 # to make the genksyms input.
 343 #
 344 # These mirror gensymtypes_c and co above, keep them in synch.
 345 cmd_gensymtypes_S =                                                         \
 346     (echo "\#include <linux/kernel.h>" ;                                    \
 347      echo "\#include <asm/asm-prototypes.h>" ;                              \
 348     $(CPP) $(a_flags) $< |                                                  \
 349      grep "\<___EXPORT_SYMBOL\>" |                                          \
 350      sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
 351     $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
 352     $(GENKSYMS) $(if $(1), -T $(2))                                         \
 353      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
 354      $(if $(KBUILD_PRESERVE),-p)                                            \
 355      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 356
 357 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
 358 cmd_cc_symtypes_S =                                                         \
 359     set -e;                                                                 \
 360     $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
 361     test -s $@ || rm -f $@
 362
 363 $(obj)/%.symtypes : $(src)/%.S FORCE
 364         $(call cmd,cc_symtypes_S)
 365
 366
 367 quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
 368 cmd_cpp_s_S       = $(CPP) $(a_flags) -o $@ $<
 369
 370 $(obj)/%.s: $(src)/%.S FORCE
 371         $(call if_changed_dep,cpp_s_S)
 372
 373 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 374
 375 ifndef CONFIG_MODVERSIONS
 376 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 377
 378 else
 379
 380 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
 381
 382 ifeq ($(ASM_PROTOTYPES),)
 383 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 384
 385 else
 386
 387 # versioning matches the C process described above, with difference that
 388 # we parse asm-prototypes.h C header to get function definitions.
 389
 390 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
 391
 392 cmd_modversions_S =                                                             \
 393         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 394                 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
 395                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 396                                                                                 \
 397                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 398                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 399                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 400         else                                                                    \
 401                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 402         fi;
 403 endif
 404 endif
 405
 406 $(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE
 407         $(call if_changed_rule,as_o_S)
 408
 409 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 410 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 411
 412 # Linker scripts preprocessor (.lds.S -> .lds)
 413 # ---------------------------------------------------------------------------
 414 quiet_cmd_cpp_lds_S = LDS     $@
 415       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
 416                              -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
 417
 418 $(obj)/%.lds: $(src)/%.lds.S FORCE
 419         $(call if_changed_dep,cpp_lds_S)
 420
 421 # ASN.1 grammar
 422 # ---------------------------------------------------------------------------
 423 quiet_cmd_asn1_compiler = ASN.1   $@
 424       cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
 425                                 $(subst .h,.c,$@) $(subst .c,.h,$@)
 426
 427 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
 428
 429 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
 430         $(call cmd,asn1_compiler)
 431
 432 # Build the compiled-in targets
 433 # ---------------------------------------------------------------------------
 434
 435 # To build objects in subdirs, we need to descend into the directories
 436 $(sort $(subdir-obj-y)): $(subdir-ym) ;
 437
 438 #
 439 # Rule to compile a set of .o files into one .o file
 440 #
 441 ifdef builtin-target
 442
 443 ifdef CONFIG_THIN_ARCHIVES
 444   cmd_make_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
 445   cmd_make_empty_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
 446   quiet_cmd_link_o_target = AR      $@
 447 else
 448   cmd_make_builtin = $(LD) $(ld_flags) -r -o
 449   cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS)
 450   quiet_cmd_link_o_target = LD      $@
 451 endif
 452
 453 # If the list of objects to link is empty, just create an empty built-in.o
 454 cmd_link_o_target = $(if $(strip $(obj-y)),\
 455                       $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \
 456                       $(cmd_secanalysis),\
 457                       $(cmd_make_empty_builtin) $@)
 458
 459 $(builtin-target): $(obj-y) FORCE
 460         $(call if_changed,link_o_target)
 461
 462 targets += $(builtin-target)
 463 endif # builtin-target
 464
 465 #
 466 # Rule to create modules.order file
 467 #
 468 # Create commands to either record .ko file or cat modules.order from
 469 # a subdirectory
 470 modorder-cmds =                                         \
 471         $(foreach m, $(modorder),                       \
 472                 $(if $(filter %/modules.order, $m),     \
 473                         cat $m;, echo kernel/$m;))
 474
 475 $(modorder-target): $(subdir-ym) FORCE
 476         $(Q)(cat /dev/null; $(modorder-cmds)) > $@
 477
 478 #
 479 # Rule to compile a set of .o files into one .a file
 480 #
 481 ifdef lib-target
 482 quiet_cmd_link_l_target = AR      $@
 483
 484 ifdef CONFIG_THIN_ARCHIVES
 485   cmd_link_l_target = rm -f $@; $(AR) rcsT$(KBUILD_ARFLAGS) $@ $(lib-y)
 486 else
 487   cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
 488 endif
 489
 490 $(lib-target): $(lib-y) FORCE
 491         $(call if_changed,link_l_target)
 492
 493 targets += $(lib-target)
 494
 495 dummy-object = $(obj)/.lib_exports.o
 496 ksyms-lds = $(dot-target).lds
 497 ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
 498 ref_prefix = EXTERN(_
 499 else
 500 ref_prefix = EXTERN(
 501 endif
 502
 503 quiet_cmd_export_list = EXPORTS $@
 504 cmd_export_list = $(OBJDUMP) -h $< | \
 505         sed -ne '/___ksymtab/{s/.*+/$(ref_prefix)/;s/ .*/)/;p}' >$(ksyms-lds);\
 506         rm -f $(dummy-object);\
 507         $(AR) rcs$(KBUILD_ARFLAGS) $(dummy-object);\
 508         $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
 509         rm $(dummy-object) $(ksyms-lds)
 510
 511 $(obj)/lib-ksyms.o: $(lib-target) FORCE
 512         $(call if_changed,export_list)
 513
 514 targets += $(obj)/lib-ksyms.o
 515
 516 endif
 517
 518 #
 519 # Rule to link composite objects
 520 #
 521 #  Composite objects are specified in kbuild makefile as follows:
 522 #    <composite-object>-objs := <list of .o files>
 523 #  or
 524 #    <composite-object>-y    := <list of .o files>
 525 #  or
 526 #    <composite-object>-m    := <list of .o files>
 527 #  The -m syntax only works if <composite object> is a module
 528 link_multi_deps =                     \
 529 $(filter $(addprefix $(obj)/,         \
 530 $($(subst $(obj)/,,$(@:.o=-objs)))    \
 531 $($(subst $(obj)/,,$(@:.o=-y)))       \
 532 $($(subst $(obj)/,,$(@:.o=-m)))), $^)
 533
 534 quiet_cmd_link_multi-y = LD      $@
 535 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
 536
 537 quiet_cmd_link_multi-m = LD [M]  $@
 538 cmd_link_multi-m = $(cmd_link_multi-y)
 539
 540 $(multi-used-y): FORCE
 541         $(call if_changed,link_multi-y)
 542 $(call multi_depend, $(multi-used-y), .o, -objs -y)
 543
 544 $(multi-used-m): FORCE
 545         $(call if_changed,link_multi-m)
 546         @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
 547            $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
 548 $(call multi_depend, $(multi-used-m), .o, -objs -y -m)
 549
 550 targets += $(multi-used-y) $(multi-used-m)
 551
 552
 553 # Descending
 554 # ---------------------------------------------------------------------------
 555
 556 PHONY += $(subdir-ym)
 557 $(subdir-ym):
 558         $(Q)$(MAKE) $(build)=$@
 559
 560 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 561 # ---------------------------------------------------------------------------
 562
 563 PHONY += FORCE
 564
 565 FORCE:
 566
 567 # Read all saved command lines and dependencies for the $(targets) we
 568 # may be building above, using $(if_changed{,_dep}). As an
 569 # optimization, we don't need to read them if the target does not
 570 # exist, we will rebuild anyway in that case.
 571
 572 targets := $(wildcard $(sort $(targets)))
 573 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 574
 575 ifneq ($(cmd_files),)
 576   include $(cmd_files)
 577 endif
 578
 579 # Declare the contents of the .PHONY variable as phony.  We keep that
 580 # information in a variable se we can use it in if_changed and friends.
 581
 582 .PHONY: $(PHONY)