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      $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
 168      $(if $(KBUILD_PRESERVE),-p)                                            \
 169      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 170
 171 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 172 cmd_cc_symtypes_c =                                                         \
 173     set -e;                                                                 \
 174     $(call cmd_gensymtypes_c,true,$@) >/dev/null;                           \
 175     test -s $@ || rm -f $@
 176
 177 $(obj)/%.symtypes : $(src)/%.c FORCE
 178         $(call cmd,cc_symtypes_c)
 179
 180 # LLVM assembly
 181 # Generate .ll files from .c
 182 quiet_cmd_cc_ll_c = CC $(quiet_modtag)  $@
 183       cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
 184
 185 $(obj)/%.ll: $(src)/%.c FORCE
 186         $(call if_changed_dep,cc_ll_c)
 187
 188 # C (.c) files
 189 # The C file is compiled and updated dependency information is generated.
 190 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 191
 192 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 193
 194 ifndef CONFIG_MODVERSIONS
 195 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 196
 197 else
 198 # When module versioning is enabled the following steps are executed:
 199 # o compile a .tmp_<file>.o from <file>.c
 200 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
 201 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
 202 #   are done.
 203 # o otherwise, we calculate symbol versions using the good old
 204 #   genksyms on the preprocessed source and postprocess them in a way
 205 #   that they are usable as a linker script
 206 # o generate <file>.o from .tmp_<file>.o using the linker to
 207 #   replace the unresolved symbols __crc_exported_symbol with
 208 #   the actual value of the checksum generated by genksyms
 209
 210 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 211
 212 cmd_modversions_c =                                                             \
 213         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 214                 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
 215                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 216                                                                                 \
 217                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 218                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 219                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 220         else                                                                    \
 221                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 222         fi;
 223 endif
 224
 225 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 226 ifdef BUILD_C_RECORDMCOUNT
 227 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
 228   RECORDMCOUNT_FLAGS = -w
 229 endif
 230 # Due to recursion, we must skip empty.o.
 231 # The empty.o file is created in the make process in order to determine
 232 # the target endianness and word size. It is made before all other C
 233 # files, including recordmcount.
 234 sub_cmd_record_mcount =                                 \
 235         if [ $(@) != "scripts/mod/empty.o" ]; then      \
 236                 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
 237         fi;
 238 recordmcount_source := $(srctree)/scripts/recordmcount.c \
 239                     $(srctree)/scripts/recordmcount.h
 240 else
 241 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 242         "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
 243         "$(if $(CONFIG_64BIT),64,32)" \
 244         "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
 245         "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
 246         "$(if $(part-of-module),1,0)" "$(@)";
 247 recordmcount_source := $(srctree)/scripts/recordmcount.pl
 248 endif # BUILD_C_RECORDMCOUNT
 249 cmd_record_mcount =                                             \
 250         if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" =   \
 251              "$(CC_FLAGS_FTRACE)" ]; then                       \
 252                 $(sub_cmd_record_mcount)                        \
 253         fi;
 254 endif # CONFIG_FTRACE_MCOUNT_RECORD
 255
 256 ifdef CONFIG_STACK_VALIDATION
 257 ifneq ($(SKIP_STACK_VALIDATION),1)
 258
 259 __objtool_obj := $(objtree)/tools/objtool/objtool
 260
 261 objtool_args = $(if $(CONFIG_ORC_UNWINDER),orc generate,check)
 262
 263 ifndef CONFIG_FRAME_POINTER
 264 objtool_args += --no-fp
 265 endif
 266 ifdef CONFIG_GCOV_KERNEL
 267 objtool_args += --no-unreachable
 268 else
 269 objtool_args += $(call cc-ifversion, -lt, 0405, --no-unreachable)
 270 endif
 271
 272 # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
 273 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
 274 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
 275 cmd_objtool = $(if $(patsubst y%,, \
 276         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
 277         $(__objtool_obj) $(objtool_args) "$(@)";)
 278 objtool_obj = $(if $(patsubst y%,, \
 279         $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
 280         $(__objtool_obj))
 281
 282 endif # SKIP_STACK_VALIDATION
 283 endif # CONFIG_STACK_VALIDATION
 284
 285 # Rebuild all objects when objtool changes, or is enabled/disabled.
 286 objtool_dep = $(objtool_obj)                                    \
 287               $(wildcard include/config/orc/unwinder.h          \
 288                          include/config/stack/validation.h)
 289
 290 define rule_cc_o_c
 291         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
 292         $(call cmd_and_fixdep,cc_o_c)                                     \
 293         $(cmd_modversions_c)                                              \
 294         $(call echo-cmd,objtool) $(cmd_objtool)                           \
 295         $(call echo-cmd,record_mcount) $(cmd_record_mcount)
 296 endef
 297
 298 define rule_as_o_S
 299         $(call cmd_and_fixdep,as_o_S)                                     \
 300         $(cmd_modversions_S)                                              \
 301         $(call echo-cmd,objtool) $(cmd_objtool)
 302 endef
 303
 304 # List module undefined symbols (or empty line if not enabled)
 305 ifdef CONFIG_TRIM_UNUSED_KSYMS
 306 cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
 307 else
 308 cmd_undef_syms = echo
 309 endif
 310
 311 # Built-in and composite module parts
 312 $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
 313         $(call cmd,force_checksrc)
 314         $(call if_changed_rule,cc_o_c)
 315
 316 # Single-part modules are special since we need to mark them in $(MODVERDIR)
 317
 318 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
 319         $(call cmd,force_checksrc)
 320         $(call if_changed_rule,cc_o_c)
 321         @{ echo $(@:.o=.ko); echo $@; \
 322            $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
 323
 324 quiet_cmd_cc_lst_c = MKLST   $@
 325       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
 326                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
 327                                      System.map $(OBJDUMP) > $@
 328
 329 $(obj)/%.lst: $(src)/%.c FORCE
 330         $(call if_changed_dep,cc_lst_c)
 331
 332 # Compile assembler sources (.S)
 333 # ---------------------------------------------------------------------------
 334
 335 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
 336
 337 $(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 338 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 339
 340 # .S file exports must have their C prototypes defined in asm/asm-prototypes.h
 341 # or a file that it includes, in order to get versioned symbols. We build a
 342 # dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
 343 # the .S file (with trailing ';'), and run genksyms on that, to extract vers.
 344 #
 345 # This is convoluted. The .S file must first be preprocessed to run guards and
 346 # expand names, then the resulting exports must be constructed into plain
 347 # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
 348 # to make the genksyms input.
 349 #
 350 # These mirror gensymtypes_c and co above, keep them in synch.
 351 cmd_gensymtypes_S =                                                         \
 352     (echo "\#include <linux/kernel.h>" ;                                    \
 353      echo "\#include <asm/asm-prototypes.h>" ;                              \
 354     $(CPP) $(a_flags) $< |                                                  \
 355      grep "\<___EXPORT_SYMBOL\>" |                                          \
 356      sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
 357     $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
 358     $(GENKSYMS) $(if $(1), -T $(2))                                         \
 359      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
 360      $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
 361      $(if $(KBUILD_PRESERVE),-p)                                            \
 362      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 363
 364 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
 365 cmd_cc_symtypes_S =                                                         \
 366     set -e;                                                                 \
 367     $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
 368     test -s $@ || rm -f $@
 369
 370 $(obj)/%.symtypes : $(src)/%.S FORCE
 371         $(call cmd,cc_symtypes_S)
 372
 373
 374 quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
 375 cmd_cpp_s_S       = $(CPP) $(a_flags) -o $@ $<
 376
 377 $(obj)/%.s: $(src)/%.S FORCE
 378         $(call if_changed_dep,cpp_s_S)
 379
 380 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 381
 382 ifndef CONFIG_MODVERSIONS
 383 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 384
 385 else
 386
 387 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
 388
 389 ifeq ($(ASM_PROTOTYPES),)
 390 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 391
 392 else
 393
 394 # versioning matches the C process described above, with difference that
 395 # we parse asm-prototypes.h C header to get function definitions.
 396
 397 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
 398
 399 cmd_modversions_S =                                                             \
 400         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 401                 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
 402                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 403                                                                                 \
 404                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 405                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 406                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 407         else                                                                    \
 408                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 409         fi;
 410 endif
 411 endif
 412
 413 $(obj)/%.o: $(src)/%.S $(objtool_dep) FORCE
 414         $(call if_changed_rule,as_o_S)
 415
 416 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 417 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 418
 419 # Linker scripts preprocessor (.lds.S -> .lds)
 420 # ---------------------------------------------------------------------------
 421 quiet_cmd_cpp_lds_S = LDS     $@
 422       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
 423                              -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
 424
 425 $(obj)/%.lds: $(src)/%.lds.S FORCE
 426         $(call if_changed_dep,cpp_lds_S)
 427
 428 # ASN.1 grammar
 429 # ---------------------------------------------------------------------------
 430 quiet_cmd_asn1_compiler = ASN.1   $@
 431       cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
 432                                 $(subst .h,.c,$@) $(subst .c,.h,$@)
 433
 434 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
 435
 436 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
 437         $(call cmd,asn1_compiler)
 438
 439 # Build the compiled-in targets
 440 # ---------------------------------------------------------------------------
 441
 442 # To build objects in subdirs, we need to descend into the directories
 443 $(sort $(subdir-obj-y)): $(subdir-ym) ;
 444
 445 #
 446 # Rule to compile a set of .o files into one .o file
 447 #
 448 ifdef builtin-target
 449
 450 ifdef CONFIG_THIN_ARCHIVES
 451   cmd_make_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS)
 452   cmd_make_empty_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS)
 453   quiet_cmd_link_o_target = AR      $@
 454 else
 455   cmd_make_builtin = $(LD) $(ld_flags) -r -o
 456   cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS)
 457   quiet_cmd_link_o_target = LD      $@
 458 endif
 459
 460 # If the list of objects to link is empty, just create an empty built-in.o
 461 cmd_link_o_target = $(if $(strip $(obj-y)),\
 462                       $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \
 463                       $(cmd_secanalysis),\
 464                       $(cmd_make_empty_builtin) $@)
 465
 466 $(builtin-target): $(obj-y) FORCE
 467         $(call if_changed,link_o_target)
 468
 469 targets += $(builtin-target)
 470 endif # builtin-target
 471
 472 #
 473 # Rule to create modules.order file
 474 #
 475 # Create commands to either record .ko file or cat modules.order from
 476 # a subdirectory
 477 modorder-cmds =                                         \
 478         $(foreach m, $(modorder),                       \
 479                 $(if $(filter %/modules.order, $m),     \
 480                         cat $m;, echo kernel/$m;))
 481
 482 $(modorder-target): $(subdir-ym) FORCE
 483         $(Q)(cat /dev/null; $(modorder-cmds)) > $@
 484
 485 #
 486 # Rule to compile a set of .o files into one .a file
 487 #
 488 ifdef lib-target
 489 quiet_cmd_link_l_target = AR      $@
 490
 491 ifdef CONFIG_THIN_ARCHIVES
 492   cmd_link_l_target = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(lib-y)
 493 else
 494   cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
 495 endif
 496
 497 $(lib-target): $(lib-y) FORCE
 498         $(call if_changed,link_l_target)
 499
 500 targets += $(lib-target)
 501
 502 dummy-object = $(obj)/.lib_exports.o
 503 ksyms-lds = $(dot-target).lds
 504 ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
 505 ref_prefix = EXTERN(_
 506 else
 507 ref_prefix = EXTERN(
 508 endif
 509
 510 quiet_cmd_export_list = EXPORTS $@
 511 cmd_export_list = $(OBJDUMP) -h $< | \
 512         sed -ne '/___ksymtab/s/.*+\([^ ]*\).*/$(ref_prefix)\1)/p' >$(ksyms-lds);\
 513         rm -f $(dummy-object);\
 514         echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\
 515         $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
 516         rm $(dummy-object) $(ksyms-lds)
 517
 518 $(obj)/lib-ksyms.o: $(lib-target) FORCE
 519         $(call if_changed,export_list)
 520
 521 targets += $(obj)/lib-ksyms.o
 522
 523 endif
 524
 525 #
 526 # Rule to link composite objects
 527 #
 528 #  Composite objects are specified in kbuild makefile as follows:
 529 #    <composite-object>-objs := <list of .o files>
 530 #  or
 531 #    <composite-object>-y    := <list of .o files>
 532 #  or
 533 #    <composite-object>-m    := <list of .o files>
 534 #  The -m syntax only works if <composite object> is a module
 535 link_multi_deps =                     \
 536 $(filter $(addprefix $(obj)/,         \
 537 $($(subst $(obj)/,,$(@:.o=-objs)))    \
 538 $($(subst $(obj)/,,$(@:.o=-y)))       \
 539 $($(subst $(obj)/,,$(@:.o=-m)))), $^)
 540
 541 cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
 542
 543 ifdef CONFIG_THIN_ARCHIVES
 544   quiet_cmd_link_multi-y = AR      $@
 545   cmd_link_multi-y = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) $@ $(link_multi_deps)
 546 else
 547   quiet_cmd_link_multi-y = LD      $@
 548   cmd_link_multi-y = $(cmd_link_multi-link)
 549 endif
 550
 551 quiet_cmd_link_multi-m = LD [M]  $@
 552 cmd_link_multi-m = $(cmd_link_multi-link)
 553
 554 $(multi-used-y): FORCE
 555         $(call if_changed,link_multi-y)
 556 $(call multi_depend, $(multi-used-y), .o, -objs -y)
 557
 558 $(multi-used-m): FORCE
 559         $(call if_changed,link_multi-m)
 560         @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
 561            $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
 562 $(call multi_depend, $(multi-used-m), .o, -objs -y -m)
 563
 564 targets += $(multi-used-y) $(multi-used-m)
 565
 566
 567 # Descending
 568 # ---------------------------------------------------------------------------
 569
 570 PHONY += $(subdir-ym)
 571 $(subdir-ym):
 572         $(Q)$(MAKE) $(build)=$@
 573
 574 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 575 # ---------------------------------------------------------------------------
 576
 577 PHONY += FORCE
 578
 579 FORCE:
 580
 581 # Read all saved command lines and dependencies for the $(targets) we
 582 # may be building above, using $(if_changed{,_dep}). As an
 583 # optimization, we don't need to read them if the target does not
 584 # exist, we will rebuild anyway in that case.
 585
 586 targets := $(wildcard $(sort $(targets)))
 587 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 588
 589 ifneq ($(cmd_files),)
 590   include $(cmd_files)
 591 endif
 592
 593 # Declare the contents of the .PHONY variable as phony.  We keep that
 594 # information in a variable se we can use it in if_changed and friends.
 595
 596 .PHONY: $(PHONY)