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 += $(call cc-option, -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 # Clang
  75 warning-1 += $(call cc-disable-warning, initializer-overrides)
  76 warning-1 += $(call cc-disable-warning, unused-value)
  77 warning-1 += $(call cc-disable-warning, format)
  78 warning-1 += $(call cc-disable-warning, unknown-warning-option)
  79 warning-1 += $(call cc-disable-warning, sign-compare)
  80 warning-1 += $(call cc-disable-warning, format-zero-length)
  81 warning-1 += $(call cc-disable-warning, uninitialized)
  82 warning-1 += $(call cc-option, -fcatch-undefined-behavior)
  83
  84 warning-2 := -Waggregate-return
  85 warning-2 += -Wcast-align
  86 warning-2 += -Wdisabled-optimization
  87 warning-2 += -Wnested-externs
  88 warning-2 += -Wshadow
  89 warning-2 += $(call cc-option, -Wlogical-op)
  90 warning-2 += $(call cc-option, -Wmissing-field-initializers)
  91
  92 warning-3 := -Wbad-function-cast
  93 warning-3 += -Wcast-qual
  94 warning-3 += -Wconversion
  95 warning-3 += -Wpacked
  96 warning-3 += -Wpadded
  97 warning-3 += -Wpointer-arith
  98 warning-3 += -Wredundant-decls
  99 warning-3 += -Wswitch-default
 100 warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
 101 warning-3 += $(call cc-option, -Wvla)
 102
 103 warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
 104 warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
 105 warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
 106
 107 ifeq ("$(strip $(warning))","")
 108         $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
 109 endif
 110
 111 KBUILD_CFLAGS += $(warning)
 112 endif
 113
 114 include scripts/Makefile.lib
 115
 116 ifdef host-progs
 117 ifneq ($(hostprogs-y),$(host-progs))
 118 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
 119 hostprogs-y += $(host-progs)
 120 endif
 121 endif
 122
 123 # Do not include host rules unless needed
 124 ifneq ($(hostprogs-y)$(hostprogs-m),)
 125 include scripts/Makefile.host
 126 endif
 127
 128 ifneq ($(KBUILD_SRC),)
 129 # Create output directory if not already present
 130 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
 131
 132 # Create directories for object files if directory does not exist
 133 # Needed when obj-y := dir/file.o syntax is used
 134 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
 135 endif
 136
 137 ifndef obj
 138 $(warning kbuild: Makefile.build is included improperly)
 139 endif
 140
 141 # ===========================================================================
 142
 143 ifneq ($(strip $(lib-y) $(lib-m) $(lib-n) $(lib-)),)
 144 lib-target := $(obj)/lib.a
 145 endif
 146
 147 ifneq ($(strip $(obj-y) $(obj-m) $(obj-n) $(obj-) $(subdir-m) $(lib-target)),)
 148 builtin-target := $(obj)/built-in.o
 149 endif
 150
 151 modorder-target := $(obj)/modules.order
 152
 153 # We keep a list of all modules in $(MODVERDIR)
 154
 155 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
 156          $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
 157          $(subdir-ym) $(always)
 158         @:
 159
 160 # Linus' kernel sanity checking tool
 161 ifneq ($(KBUILD_CHECKSRC),0)
 162   ifeq ($(KBUILD_CHECKSRC),2)
 163     quiet_cmd_force_checksrc = CHECK   $<
 164           cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 165   else
 166       quiet_cmd_checksrc     = CHECK   $<
 167             cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 168   endif
 169 endif
 170
 171 # Do section mismatch analysis for each module/built-in.o
 172 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 173   cmd_secanalysis = ; scripts/mod/modpost $@
 174 endif
 175
 176 # Compile C sources (.c)
 177 # ---------------------------------------------------------------------------
 178
 179 # Default is built-in, unless we know otherwise
 180 modkern_cflags =                                          \
 181         $(if $(part-of-module),                           \
 182                 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 183                 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
 184 quiet_modtag := $(empty)   $(empty)
 185
 186 $(real-objs-m)        : part-of-module := y
 187 $(real-objs-m:.o=.i)  : part-of-module := y
 188 $(real-objs-m:.o=.s)  : part-of-module := y
 189 $(real-objs-m:.o=.lst): part-of-module := y
 190
 191 $(real-objs-m)        : quiet_modtag := [M]
 192 $(real-objs-m:.o=.i)  : quiet_modtag := [M]
 193 $(real-objs-m:.o=.s)  : quiet_modtag := [M]
 194 $(real-objs-m:.o=.lst): quiet_modtag := [M]
 195
 196 $(obj-m)              : quiet_modtag := [M]
 197
 198 # Default for not multi-part modules
 199 modname = $(basetarget)
 200
 201 $(multi-objs-m)         : modname = $(modname-multi)
 202 $(multi-objs-m:.o=.i)   : modname = $(modname-multi)
 203 $(multi-objs-m:.o=.s)   : modname = $(modname-multi)
 204 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
 205 $(multi-objs-y)         : modname = $(modname-multi)
 206 $(multi-objs-y:.o=.i)   : modname = $(modname-multi)
 207 $(multi-objs-y:.o=.s)   : modname = $(modname-multi)
 208 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
 209
 210 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
 211 cmd_cc_s_c       = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
 212
 213 $(obj)/%.s: $(src)/%.c FORCE
 214         $(call if_changed_dep,cc_s_c)
 215
 216 quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@
 217 cmd_cc_i_c       = $(CPP) $(c_flags)   -o $@ $<
 218
 219 $(obj)/%.i: $(src)/%.c FORCE
 220         $(call if_changed_dep,cc_i_c)
 221
 222 cmd_gensymtypes =                                                           \
 223     $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
 224     $(GENKSYMS) $(if $(1), -T $(2))                                         \
 225      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
 226      $(if $(KBUILD_PRESERVE),-p)                                            \
 227      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 228
 229 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 230 cmd_cc_symtypes_c =                                                         \
 231     set -e;                                                                 \
 232     $(call cmd_gensymtypes,true,$@) >/dev/null;                             \
 233     test -s $@ || rm -f $@
 234
 235 $(obj)/%.symtypes : $(src)/%.c FORCE
 236         $(call cmd,cc_symtypes_c)
 237
 238 # C (.c) files
 239 # The C file is compiled and updated dependency information is generated.
 240 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 241
 242 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 243
 244 ifndef CONFIG_MODVERSIONS
 245 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 246
 247 else
 248 # When module versioning is enabled the following steps are executed:
 249 # o compile a .tmp_<file>.o from <file>.c
 250 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
 251 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
 252 #   are done.
 253 # o otherwise, we calculate symbol versions using the good old
 254 #   genksyms on the preprocessed source and postprocess them in a way
 255 #   that they are usable as a linker script
 256 # o generate <file>.o from .tmp_<file>.o using the linker to
 257 #   replace the unresolved symbols __crc_exported_symbol with
 258 #   the actual value of the checksum generated by genksyms
 259
 260 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 261 cmd_modversions =                                                               \
 262         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 263                 $(call cmd_gensymtypes,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))    \
 264                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 265                                                                                 \
 266                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 267                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 268                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 269         else                                                                    \
 270                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 271         fi;
 272 endif
 273
 274 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 275 ifdef BUILD_C_RECORDMCOUNT
 276 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
 277   RECORDMCOUNT_FLAGS = -w
 278 endif
 279 # Due to recursion, we must skip empty.o.
 280 # The empty.o file is created in the make process in order to determine
 281 #  the target endianness and word size. It is made before all other C
 282 #  files, including recordmcount.
 283 sub_cmd_record_mcount =                                 \
 284         if [ $(@) != "scripts/mod/empty.o" ]; then      \
 285                 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
 286         fi;
 287 recordmcount_source := $(srctree)/scripts/recordmcount.c \
 288                     $(srctree)/scripts/recordmcount.h
 289 else
 290 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 291         "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
 292         "$(if $(CONFIG_64BIT),64,32)" \
 293         "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
 294         "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
 295         "$(if $(part-of-module),1,0)" "$(@)";
 296 recordmcount_source := $(srctree)/scripts/recordmcount.pl
 297 endif
 298 cmd_record_mcount =                                             \
 299         if [ "$(findstring -pg,$(_c_flags))" = "-pg" ]; then    \
 300                 $(sub_cmd_record_mcount)                        \
 301         fi;
 302 endif
 303
 304 define rule_cc_o_c
 305         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
 306         $(call echo-cmd,cc_o_c) $(cmd_cc_o_c);                            \
 307         $(cmd_modversions)                                                \
 308         $(call echo-cmd,record_mcount)                                    \
 309         $(cmd_record_mcount)                                              \
 310         scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' >    \
 311                                                       $(dot-target).tmp;  \
 312         rm -f $(depfile);                                                 \
 313         mv -f $(dot-target).tmp $(dot-target).cmd
 314 endef
 315
 316 # Built-in and composite module parts
 317 $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
 318         $(call cmd,force_checksrc)
 319         $(call if_changed_rule,cc_o_c)
 320
 321 # Single-part modules are special since we need to mark them in $(MODVERDIR)
 322
 323 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
 324         $(call cmd,force_checksrc)
 325         $(call if_changed_rule,cc_o_c)
 326         @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod)
 327
 328 quiet_cmd_cc_lst_c = MKLST   $@
 329       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
 330                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
 331                                      System.map $(OBJDUMP) > $@
 332
 333 $(obj)/%.lst: $(src)/%.c FORCE
 334         $(call if_changed_dep,cc_lst_c)
 335
 336 # Compile assembler sources (.S)
 337 # ---------------------------------------------------------------------------
 338
 339 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
 340
 341 $(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 342 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 343
 344 quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
 345 cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $<
 346
 347 $(obj)/%.s: $(src)/%.S FORCE
 348         $(call if_changed_dep,as_s_S)
 349
 350 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 351 cmd_as_o_S       = $(CC) $(a_flags) -c -o $@ $<
 352
 353 $(obj)/%.o: $(src)/%.S FORCE
 354         $(call if_changed_dep,as_o_S)
 355
 356 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 357 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 358
 359 # Linker scripts preprocessor (.lds.S -> .lds)
 360 # ---------------------------------------------------------------------------
 361 quiet_cmd_cpp_lds_S = LDS     $@
 362       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
 363                              -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
 364
 365 $(obj)/%.lds: $(src)/%.lds.S FORCE
 366         $(call if_changed_dep,cpp_lds_S)
 367
 368 # ASN.1 grammar
 369 # ---------------------------------------------------------------------------
 370 quiet_cmd_asn1_compiler = ASN.1   $@
 371       cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
 372                                 $(subst .h,.c,$@) $(subst .c,.h,$@)
 373
 374 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
 375
 376 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
 377         $(call cmd,asn1_compiler)
 378
 379 # Build the compiled-in targets
 380 # ---------------------------------------------------------------------------
 381
 382 # To build objects in subdirs, we need to descend into the directories
 383 $(sort $(subdir-obj-y)): $(subdir-ym) ;
 384
 385 #
 386 # Rule to compile a set of .o files into one .o file
 387 #
 388 ifdef builtin-target
 389 quiet_cmd_link_o_target = LD      $@
 390 # If the list of objects to link is empty, just create an empty built-in.o
 391 cmd_link_o_target = $(if $(strip $(obj-y)),\
 392                       $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \
 393                       $(cmd_secanalysis),\
 394                       rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@)
 395
 396 $(builtin-target): $(obj-y) FORCE
 397         $(call if_changed,link_o_target)
 398
 399 targets += $(builtin-target)
 400 endif # builtin-target
 401
 402 #
 403 # Rule to create modules.order file
 404 #
 405 # Create commands to either record .ko file or cat modules.order from
 406 # a subdirectory
 407 modorder-cmds =                                         \
 408         $(foreach m, $(modorder),                       \
 409                 $(if $(filter %/modules.order, $m),     \
 410                         cat $m;, echo kernel/$m;))
 411
 412 $(modorder-target): $(subdir-ym) FORCE
 413         $(Q)(cat /dev/null; $(modorder-cmds)) > $@
 414
 415 #
 416 # Rule to compile a set of .o files into one .a file
 417 #
 418 ifdef lib-target
 419 quiet_cmd_link_l_target = AR      $@
 420 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
 421
 422 $(lib-target): $(lib-y) FORCE
 423         $(call if_changed,link_l_target)
 424
 425 targets += $(lib-target)
 426 endif
 427
 428 #
 429 # Rule to link composite objects
 430 #
 431 #  Composite objects are specified in kbuild makefile as follows:
 432 #    <composite-object>-objs := <list of .o files>
 433 #  or
 434 #    <composite-object>-y    := <list of .o files>
 435 link_multi_deps =                     \
 436 $(filter $(addprefix $(obj)/,         \
 437 $($(subst $(obj)/,,$(@:.o=-objs)))    \
 438 $($(subst $(obj)/,,$(@:.o=-y)))), $^)
 439
 440 quiet_cmd_link_multi-y = LD      $@
 441 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
 442
 443 quiet_cmd_link_multi-m = LD [M]  $@
 444 cmd_link_multi-m = $(cmd_link_multi-y)
 445
 446 # We would rather have a list of rules like
 447 #       foo.o: $(foo-objs)
 448 # but that's not so easy, so we rather make all composite objects depend
 449 # on the set of all their parts
 450 $(multi-used-y) : %.o: $(multi-objs-y) FORCE
 451         $(call if_changed,link_multi-y)
 452
 453 $(multi-used-m) : %.o: $(multi-objs-m) FORCE
 454         $(call if_changed,link_multi-m)
 455         @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod)
 456
 457 targets += $(multi-used-y) $(multi-used-m)
 458
 459
 460 # Descending
 461 # ---------------------------------------------------------------------------
 462
 463 PHONY += $(subdir-ym)
 464 $(subdir-ym):
 465         $(Q)$(MAKE) $(build)=$@
 466
 467 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 468 # ---------------------------------------------------------------------------
 469
 470 PHONY += FORCE
 471
 472 FORCE:
 473
 474 # Read all saved command lines and dependencies for the $(targets) we
 475 # may be building above, using $(if_changed{,_dep}). As an
 476 # optimization, we don't need to read them if the target does not
 477 # exist, we will rebuild anyway in that case.
 478
 479 targets := $(wildcard $(sort $(targets)))
 480 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 481
 482 ifneq ($(cmd_files),)
 483   include $(cmd_files)
 484 endif
 485
 486 # Declare the contents of the .PHONY variable as phony.  We keep that
 487 # information in a variable se we can use it in if_changed and friends.
 488
 489 .PHONY: $(PHONY)