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