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 #
  54 # make W=... settings
  55 #
  56 # W=1 - warnings that may be relevant and does not occur too often
  57 # W=2 - warnings that occur quite often but may still be relevant
  58 # W=3 - the more obscure warnings, can most likely be ignored
  59 #
  60 # $(call cc-option, -W...) handles gcc -W.. options which
  61 # are not supported by all versions of the compiler
  62 ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS
  63 warning-  := $(empty)
  64
  65 warning-1 := -Wextra -Wunused -Wno-unused-parameter
  66 warning-1 += -Wmissing-declarations
  67 warning-1 += -Wmissing-format-attribute
  68 warning-1 += -Wmissing-prototypes
  69 warning-1 += -Wold-style-definition
  70 warning-1 += $(call cc-option, -Wmissing-include-dirs)
  71 warning-1 += $(call cc-option, -Wunused-but-set-variable)
  72 warning-1 += $(call cc-disable-warning, missing-field-initializers)
  73
  74 warning-2 := -Waggregate-return
  75 warning-2 += -Wcast-align
  76 warning-2 += -Wdisabled-optimization
  77 warning-2 += -Wnested-externs
  78 warning-2 += -Wshadow
  79 warning-2 += $(call cc-option, -Wlogical-op)
  80 warning-2 += $(call cc-option, -Wmissing-field-initializers)
  81
  82 warning-3 := -Wbad-function-cast
  83 warning-3 += -Wcast-qual
  84 warning-3 += -Wconversion
  85 warning-3 += -Wpacked
  86 warning-3 += -Wpadded
  87 warning-3 += -Wpointer-arith
  88 warning-3 += -Wredundant-decls
  89 warning-3 += -Wswitch-default
  90 warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
  91 warning-3 += $(call cc-option, -Wvla)
  92
  93 warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
  94 warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
  95 warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
  96
  97 ifeq ("$(strip $(warning))","")
  98         $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
  99 endif
 100
 101 KBUILD_CFLAGS += $(warning)
 102 endif
 103
 104 include scripts/Makefile.lib
 105
 106 ifdef host-progs
 107 ifneq ($(hostprogs-y),$(host-progs))
 108 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
 109 hostprogs-y += $(host-progs)
 110 endif
 111 endif
 112
 113 # Do not include host rules unless needed
 114 ifneq ($(hostprogs-y)$(hostprogs-m),)
 115 include scripts/Makefile.host
 116 endif
 117
 118 ifneq ($(KBUILD_SRC),)
 119 # Create output directory if not already present
 120 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
 121
 122 # Create directories for object files if directory does not exist
 123 # Needed when obj-y := dir/file.o syntax is used
 124 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
 125 endif
 126
 127 ifndef obj
 128 $(warning kbuild: Makefile.build is included improperly)
 129 endif
 130
 131 # ===========================================================================
 132
 133 ifneq ($(strip $(lib-y) $(lib-m) $(lib-n) $(lib-)),)
 134 lib-target := $(obj)/lib.a
 135 endif
 136
 137 ifneq ($(strip $(obj-y) $(obj-m) $(obj-n) $(obj-) $(subdir-m) $(lib-target)),)
 138 builtin-target := $(obj)/built-in.o
 139 endif
 140
 141 modorder-target := $(obj)/modules.order
 142
 143 # We keep a list of all modules in $(MODVERDIR)
 144
 145 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
 146          $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
 147          $(subdir-ym) $(always)
 148         @:
 149
 150 # Linus' kernel sanity checking tool
 151 ifneq ($(KBUILD_CHECKSRC),0)
 152   ifeq ($(KBUILD_CHECKSRC),2)
 153     quiet_cmd_force_checksrc = CHECK   $<
 154           cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 155   else
 156       quiet_cmd_checksrc     = CHECK   $<
 157             cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 158   endif
 159 endif
 160
 161 # Do section mismatch analysis for each module/built-in.o
 162 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 163   cmd_secanalysis = ; scripts/mod/modpost $@
 164 endif
 165
 166 # Compile C sources (.c)
 167 # ---------------------------------------------------------------------------
 168
 169 # Default is built-in, unless we know otherwise
 170 modkern_cflags =                                          \
 171         $(if $(part-of-module),                           \
 172                 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 173                 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
 174 quiet_modtag := $(empty)   $(empty)
 175
 176 $(real-objs-m)        : part-of-module := y
 177 $(real-objs-m:.o=.i)  : part-of-module := y
 178 $(real-objs-m:.o=.s)  : part-of-module := y
 179 $(real-objs-m:.o=.lst): part-of-module := y
 180
 181 $(real-objs-m)        : quiet_modtag := [M]
 182 $(real-objs-m:.o=.i)  : quiet_modtag := [M]
 183 $(real-objs-m:.o=.s)  : quiet_modtag := [M]
 184 $(real-objs-m:.o=.lst): quiet_modtag := [M]
 185
 186 $(obj-m)              : quiet_modtag := [M]
 187
 188 # Default for not multi-part modules
 189 modname = $(basetarget)
 190
 191 $(multi-objs-m)         : modname = $(modname-multi)
 192 $(multi-objs-m:.o=.i)   : modname = $(modname-multi)
 193 $(multi-objs-m:.o=.s)   : modname = $(modname-multi)
 194 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
 195 $(multi-objs-y)         : modname = $(modname-multi)
 196 $(multi-objs-y:.o=.i)   : modname = $(modname-multi)
 197 $(multi-objs-y:.o=.s)   : modname = $(modname-multi)
 198 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
 199
 200 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
 201 cmd_cc_s_c       = $(CC) $(c_flags) -fverbose-asm -S -o $@ $<
 202
 203 $(obj)/%.s: $(src)/%.c FORCE
 204         $(call if_changed_dep,cc_s_c)
 205
 206 quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@
 207 cmd_cc_i_c       = $(CPP) $(c_flags)   -o $@ $<
 208
 209 $(obj)/%.i: $(src)/%.c FORCE
 210         $(call if_changed_dep,cc_i_c)
 211
 212 cmd_gensymtypes =                                                           \
 213     $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
 214     $(GENKSYMS) $(if $(1), -T $(2)) -a $(ARCH)                              \
 215      $(if $(KBUILD_PRESERVE),-p)                                            \
 216      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 217
 218 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 219 cmd_cc_symtypes_c =                                                         \
 220     set -e;                                                                 \
 221     $(call cmd_gensymtypes,true,$@) >/dev/null;                             \
 222     test -s $@ || rm -f $@
 223
 224 $(obj)/%.symtypes : $(src)/%.c FORCE
 225         $(call cmd,cc_symtypes_c)
 226
 227 # C (.c) files
 228 # The C file is compiled and updated dependency information is generated.
 229 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 230
 231 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 232
 233 ifndef CONFIG_MODVERSIONS
 234 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 235
 236 else
 237 # When module versioning is enabled the following steps are executed:
 238 # o compile a .tmp_<file>.o from <file>.c
 239 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
 240 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
 241 #   are done.
 242 # o otherwise, we calculate symbol versions using the good old
 243 #   genksyms on the preprocessed source and postprocess them in a way
 244 #   that they are usable as a linker script
 245 # o generate <file>.o from .tmp_<file>.o using the linker to
 246 #   replace the unresolved symbols __crc_exported_symbol with
 247 #   the actual value of the checksum generated by genksyms
 248
 249 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 250 cmd_modversions =                                                               \
 251         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 252                 $(call cmd_gensymtypes,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))    \
 253                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 254                                                                                 \
 255                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 256                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 257                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 258         else                                                                    \
 259                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 260         fi;
 261 endif
 262
 263 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 264 ifdef BUILD_C_RECORDMCOUNT
 265 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
 266   RECORDMCOUNT_FLAGS = -w
 267 endif
 268 # Due to recursion, we must skip empty.o.
 269 # The empty.o file is created in the make process in order to determine
 270 #  the target endianness and word size. It is made before all other C
 271 #  files, including recordmcount.
 272 sub_cmd_record_mcount =                                 \
 273         if [ $(@) != "scripts/mod/empty.o" ]; then      \
 274                 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
 275         fi;
 276 recordmcount_source := $(srctree)/scripts/recordmcount.c \
 277                     $(srctree)/scripts/recordmcount.h
 278 else
 279 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 280         "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
 281         "$(if $(CONFIG_64BIT),64,32)" \
 282         "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
 283         "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
 284         "$(if $(part-of-module),1,0)" "$(@)";
 285 recordmcount_source := $(srctree)/scripts/recordmcount.pl
 286 endif
 287 cmd_record_mcount =                                             \
 288         if [ "$(findstring -pg,$(_c_flags))" = "-pg" ]; then    \
 289                 $(sub_cmd_record_mcount)                        \
 290         fi;
 291 endif
 292
 293 define rule_cc_o_c
 294         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
 295         $(call echo-cmd,cc_o_c) $(cmd_cc_o_c);                            \
 296         $(cmd_modversions)                                                \
 297         $(call echo-cmd,record_mcount)                                    \
 298         $(cmd_record_mcount)                                              \
 299         scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' >    \
 300                                                       $(dot-target).tmp;  \
 301         rm -f $(depfile);                                                 \
 302         mv -f $(dot-target).tmp $(dot-target).cmd
 303 endef
 304
 305 # Built-in and composite module parts
 306 $(obj)/%.o: $(src)/%.c $(recordmcount_source) 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) FORCE
 313         $(call cmd,force_checksrc)
 314         $(call if_changed_rule,cc_o_c)
 315         @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod)
 316
 317 quiet_cmd_cc_lst_c = MKLST   $@
 318       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
 319                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
 320                                      System.map $(OBJDUMP) > $@
 321
 322 $(obj)/%.lst: $(src)/%.c FORCE
 323         $(call if_changed_dep,cc_lst_c)
 324
 325 # Compile assembler sources (.S)
 326 # ---------------------------------------------------------------------------
 327
 328 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
 329
 330 $(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 331 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 332
 333 quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
 334 cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $<
 335
 336 $(obj)/%.s: $(src)/%.S FORCE
 337         $(call if_changed_dep,as_s_S)
 338
 339 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 340 cmd_as_o_S       = $(CC) $(a_flags) -c -o $@ $<
 341
 342 $(obj)/%.o: $(src)/%.S FORCE
 343         $(call if_changed_dep,as_o_S)
 344
 345 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 346 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 347
 348 # Linker scripts preprocessor (.lds.S -> .lds)
 349 # ---------------------------------------------------------------------------
 350 quiet_cmd_cpp_lds_S = LDS     $@
 351       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
 352                              -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
 353
 354 $(obj)/%.lds: $(src)/%.lds.S FORCE
 355         $(call if_changed_dep,cpp_lds_S)
 356
 357 # Build the compiled-in targets
 358 # ---------------------------------------------------------------------------
 359
 360 # To build objects in subdirs, we need to descend into the directories
 361 $(sort $(subdir-obj-y)): $(subdir-ym) ;
 362
 363 #
 364 # Rule to compile a set of .o files into one .o file
 365 #
 366 ifdef builtin-target
 367 quiet_cmd_link_o_target = LD      $@
 368 # If the list of objects to link is empty, just create an empty built-in.o
 369 cmd_link_o_target = $(if $(strip $(obj-y)),\
 370                       $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \
 371                       $(cmd_secanalysis),\
 372                       rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@)
 373
 374 $(builtin-target): $(obj-y) FORCE
 375         $(call if_changed,link_o_target)
 376
 377 targets += $(builtin-target)
 378 endif # builtin-target
 379
 380 #
 381 # Rule to create modules.order file
 382 #
 383 # Create commands to either record .ko file or cat modules.order from
 384 # a subdirectory
 385 modorder-cmds =                                         \
 386         $(foreach m, $(modorder),                       \
 387                 $(if $(filter %/modules.order, $m),     \
 388                         cat $m;, echo kernel/$m;))
 389
 390 $(modorder-target): $(subdir-ym) FORCE
 391         $(Q)(cat /dev/null; $(modorder-cmds)) > $@
 392
 393 #
 394 # Rule to compile a set of .o files into one .a file
 395 #
 396 ifdef lib-target
 397 quiet_cmd_link_l_target = AR      $@
 398 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
 399
 400 $(lib-target): $(lib-y) FORCE
 401         $(call if_changed,link_l_target)
 402
 403 targets += $(lib-target)
 404 endif
 405
 406 #
 407 # Rule to link composite objects
 408 #
 409 #  Composite objects are specified in kbuild makefile as follows:
 410 #    <composite-object>-objs := <list of .o files>
 411 #  or
 412 #    <composite-object>-y    := <list of .o files>
 413 link_multi_deps =                     \
 414 $(filter $(addprefix $(obj)/,         \
 415 $($(subst $(obj)/,,$(@:.o=-objs)))    \
 416 $($(subst $(obj)/,,$(@:.o=-y)))), $^)
 417
 418 quiet_cmd_link_multi-y = LD      $@
 419 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
 420
 421 quiet_cmd_link_multi-m = LD [M]  $@
 422 cmd_link_multi-m = $(cmd_link_multi-y)
 423
 424 # We would rather have a list of rules like
 425 #       foo.o: $(foo-objs)
 426 # but that's not so easy, so we rather make all composite objects depend
 427 # on the set of all their parts
 428 $(multi-used-y) : %.o: $(multi-objs-y) FORCE
 429         $(call if_changed,link_multi-y)
 430
 431 $(multi-used-m) : %.o: $(multi-objs-m) FORCE
 432         $(call if_changed,link_multi-m)
 433         @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod)
 434
 435 targets += $(multi-used-y) $(multi-used-m)
 436
 437
 438 # Descending
 439 # ---------------------------------------------------------------------------
 440
 441 PHONY += $(subdir-ym)
 442 $(subdir-ym):
 443         $(Q)$(MAKE) $(build)=$@
 444
 445 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 446 # ---------------------------------------------------------------------------
 447
 448 PHONY += FORCE
 449
 450 FORCE:
 451
 452 # Read all saved command lines and dependencies for the $(targets) we
 453 # may be building above, using $(if_changed{,_dep}). As an
 454 # optimization, we don't need to read them if the target does not
 455 # exist, we will rebuild anyway in that case.
 456
 457 targets := $(wildcard $(sort $(targets)))
 458 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 459
 460 ifneq ($(cmd_files),)
 461   include $(cmd_files)
 462 endif
 463
 464 # Declare the contents of the .PHONY variable as phony.  We keep that
 465 # information in a variable se we can use it in if_changed and friends.
 466
 467 .PHONY: $(PHONY)