linux/scripts/Makefile.build
<<
>>
Prefs
   1# ==========================================================================
   2# Building
   3# ==========================================================================
   4
   5src := $(obj)
   6
   7PHONY := __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
  13obj-y :=
  14obj-m :=
  15lib-y :=
  16lib-m :=
  17always :=
  18targets :=
  19subdir-y :=
  20subdir-m :=
  21EXTRA_AFLAGS   :=
  22EXTRA_CFLAGS   :=
  23EXTRA_CPPFLAGS :=
  24EXTRA_LDFLAGS  :=
  25asflags-y  :=
  26ccflags-y  :=
  27cppflags-y :=
  28ldflags-y  :=
  29
  30subdir-asflags-y :=
  31subdir-ccflags-y :=
  32
  33# Read auto.conf if it exists, otherwise ignore
  34-include include/config/auto.conf
  35
  36include scripts/Kbuild.include
  37
  38# For backward compatibility check that these variables do not change
  39save-cflags := $(CFLAGS)
  40
  41# The filename Kbuild has precedence over Makefile
  42kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
  43kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
  44include $(kbuild-file)
  45
  46# If the save-* variables changed error out
  47ifeq ($(KBUILD_NOPEDANTIC),)
  48        ifneq ("$(save-cflags)","$(CFLAGS)")
  49                $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
  50        endif
  51endif
  52
  53include scripts/Makefile.lib
  54
  55ifdef host-progs
  56ifneq ($(hostprogs-y),$(host-progs))
  57$(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
  58hostprogs-y += $(host-progs)
  59endif
  60endif
  61
  62# Do not include host rules unless needed
  63ifneq ($(hostprogs-y)$(hostprogs-m),)
  64include scripts/Makefile.host
  65endif
  66
  67ifneq ($(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 $(d)))
  74endif
  75
  76ifndef obj
  77$(warning kbuild: Makefile.build is included improperly)
  78endif
  79
  80# ===========================================================================
  81
  82ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
  83lib-target := $(obj)/lib.a
  84endif
  85
  86ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
  87builtin-target := $(obj)/built-in.o
  88endif
  89
  90modorder-target := $(obj)/modules.order
  91
  92# We keep a list of all modules in $(MODVERDIR)
  93
  94__build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
  95         $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
  96         $(subdir-ym) $(always)
  97        @:
  98
  99# Linus' kernel sanity checking tool
 100ifneq ($(KBUILD_CHECKSRC),0)
 101  ifeq ($(KBUILD_CHECKSRC),2)
 102    quiet_cmd_force_checksrc = CHECK   $<
 103          cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 104  else
 105      quiet_cmd_checksrc     = CHECK   $<
 106            cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 107  endif
 108endif
 109
 110# Do section mismatch analysis for each module/built-in.o
 111ifdef CONFIG_DEBUG_SECTION_MISMATCH
 112  cmd_secanalysis = ; scripts/mod/modpost $@
 113endif
 114
 115# Compile C sources (.c)
 116# ---------------------------------------------------------------------------
 117
 118# Default is built-in, unless we know otherwise
 119modkern_cflags =                                          \
 120        $(if $(part-of-module),                           \
 121                $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 122                $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
 123quiet_modtag := $(empty)   $(empty)
 124
 125$(real-objs-m)        : part-of-module := y
 126$(real-objs-m:.o=.i)  : part-of-module := y
 127$(real-objs-m:.o=.s)  : part-of-module := y
 128$(real-objs-m:.o=.lst): part-of-module := y
 129
 130$(real-objs-m)        : quiet_modtag := [M]
 131$(real-objs-m:.o=.i)  : quiet_modtag := [M]
 132$(real-objs-m:.o=.s)  : quiet_modtag := [M]
 133$(real-objs-m:.o=.lst): quiet_modtag := [M]
 134
 135$(obj-m)              : quiet_modtag := [M]
 136
 137# Default for not multi-part modules
 138modname = $(basetarget)
 139
 140$(multi-objs-m)         : modname = $(modname-multi)
 141$(multi-objs-m:.o=.i)   : modname = $(modname-multi)
 142$(multi-objs-m:.o=.s)   : modname = $(modname-multi)
 143$(multi-objs-m:.o=.lst) : modname = $(modname-multi)
 144$(multi-objs-y)         : modname = $(modname-multi)
 145$(multi-objs-y:.o=.i)   : modname = $(modname-multi)
 146$(multi-objs-y:.o=.s)   : modname = $(modname-multi)
 147$(multi-objs-y:.o=.lst) : modname = $(modname-multi)
 148
 149quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
 150cmd_cc_s_c       = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
 151
 152$(obj)/%.s: $(src)/%.c FORCE
 153        $(call if_changed_dep,cc_s_c)
 154
 155quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@
 156cmd_cc_i_c       = $(CPP) $(c_flags)   -o $@ $<
 157
 158$(obj)/%.i: $(src)/%.c FORCE
 159        $(call if_changed_dep,cc_i_c)
 160
 161cmd_gensymtypes =                                                           \
 162    $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
 163    $(GENKSYMS) $(if $(1), -T $(2))                                         \
 164     $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
 165     $(if $(KBUILD_PRESERVE),-p)                                            \
 166     -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 167
 168quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 169cmd_cc_symtypes_c =                                                         \
 170    set -e;                                                                 \
 171    $(call cmd_gensymtypes,true,$@) >/dev/null;                             \
 172    test -s $@ || rm -f $@
 173
 174$(obj)/%.symtypes : $(src)/%.c FORCE
 175        $(call cmd,cc_symtypes_c)
 176
 177# C (.c) files
 178# The C file is compiled and updated dependency information is generated.
 179# (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 180
 181quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 182
 183ifndef CONFIG_MODVERSIONS
 184cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 185
 186else
 187# When module versioning is enabled the following steps are executed:
 188# o compile a .tmp_<file>.o from <file>.c
 189# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
 190#   not export symbols, we just rename .tmp_<file>.o to <file>.o and
 191#   are done.
 192# o otherwise, we calculate symbol versions using the good old
 193#   genksyms on the preprocessed source and postprocess them in a way
 194#   that they are usable as a linker script
 195# o generate <file>.o from .tmp_<file>.o using the linker to
 196#   replace the unresolved symbols __crc_exported_symbol with
 197#   the actual value of the checksum generated by genksyms
 198
 199cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 200cmd_modversions =                                                               \
 201        if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 202                $(call cmd_gensymtypes,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))    \
 203                    > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 204                                                                                \
 205                $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 206                        -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 207                rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 208        else                                                                    \
 209                mv -f $(@D)/.tmp_$(@F) $@;                                      \
 210        fi;
 211endif
 212
 213ifdef CONFIG_FTRACE_MCOUNT_RECORD
 214ifdef BUILD_C_RECORDMCOUNT
 215ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
 216  RECORDMCOUNT_FLAGS = -w
 217endif
 218# Due to recursion, we must skip empty.o.
 219# The empty.o file is created in the make process in order to determine
 220#  the target endianness and word size. It is made before all other C
 221#  files, including recordmcount.
 222sub_cmd_record_mcount =                                 \
 223        if [ $(@) != "scripts/mod/empty.o" ]; then      \
 224                $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
 225        fi;
 226recordmcount_source := $(srctree)/scripts/recordmcount.c \
 227                    $(srctree)/scripts/recordmcount.h
 228else
 229sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 230        "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
 231        "$(if $(CONFIG_64BIT),64,32)" \
 232        "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
 233        "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
 234        "$(if $(part-of-module),1,0)" "$(@)";
 235recordmcount_source := $(srctree)/scripts/recordmcount.pl
 236endif
 237cmd_record_mcount =                                             \
 238        if [ "$(findstring -pg,$(_c_flags))" = "-pg" ]; then    \
 239                $(sub_cmd_record_mcount)                        \
 240        fi;
 241endif
 242
 243define rule_cc_o_c
 244        $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
 245        $(call echo-cmd,cc_o_c) $(cmd_cc_o_c);                            \
 246        $(cmd_modversions)                                                \
 247        $(call echo-cmd,record_mcount)                                    \
 248        $(cmd_record_mcount)                                              \
 249        scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' >    \
 250                                                      $(dot-target).tmp;  \
 251        rm -f $(depfile);                                                 \
 252        mv -f $(dot-target).tmp $(dot-target).cmd
 253endef
 254
 255# Built-in and composite module parts
 256$(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
 257        $(call cmd,force_checksrc)
 258        $(call if_changed_rule,cc_o_c)
 259
 260# Single-part modules are special since we need to mark them in $(MODVERDIR)
 261
 262$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
 263        $(call cmd,force_checksrc)
 264        $(call if_changed_rule,cc_o_c)
 265        @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod)
 266
 267quiet_cmd_cc_lst_c = MKLST   $@
 268      cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
 269                     $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
 270                                     System.map $(OBJDUMP) > $@
 271
 272$(obj)/%.lst: $(src)/%.c FORCE
 273        $(call if_changed_dep,cc_lst_c)
 274
 275# Compile assembler sources (.S)
 276# ---------------------------------------------------------------------------
 277
 278modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
 279
 280$(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 281$(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 282
 283quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
 284cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $<
 285
 286$(obj)/%.s: $(src)/%.S FORCE
 287        $(call if_changed_dep,as_s_S)
 288
 289quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 290cmd_as_o_S       = $(CC) $(a_flags) -c -o $@ $<
 291
 292$(obj)/%.o: $(src)/%.S FORCE
 293        $(call if_changed_dep,as_o_S)
 294
 295targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 296targets += $(extra-y) $(MAKECMDGOALS) $(always)
 297
 298# Linker scripts preprocessor (.lds.S -> .lds)
 299# ---------------------------------------------------------------------------
 300quiet_cmd_cpp_lds_S = LDS     $@
 301      cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
 302                             -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
 303
 304$(obj)/%.lds: $(src)/%.lds.S FORCE
 305        $(call if_changed_dep,cpp_lds_S)
 306
 307# ASN.1 grammar
 308# ---------------------------------------------------------------------------
 309quiet_cmd_asn1_compiler = ASN.1   $@
 310      cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
 311                                $(subst .h,.c,$@) $(subst .c,.h,$@)
 312
 313.PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
 314
 315$(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
 316        $(call cmd,asn1_compiler)
 317
 318# Build the compiled-in targets
 319# ---------------------------------------------------------------------------
 320
 321# To build objects in subdirs, we need to descend into the directories
 322$(sort $(subdir-obj-y)): $(subdir-ym) ;
 323
 324#
 325# Rule to compile a set of .o files into one .o file
 326#
 327ifdef builtin-target
 328quiet_cmd_link_o_target = LD      $@
 329# If the list of objects to link is empty, just create an empty built-in.o
 330cmd_link_o_target = $(if $(strip $(obj-y)),\
 331                      $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \
 332                      $(cmd_secanalysis),\
 333                      rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@)
 334
 335$(builtin-target): $(obj-y) FORCE
 336        $(call if_changed,link_o_target)
 337
 338targets += $(builtin-target)
 339endif # builtin-target
 340
 341#
 342# Rule to create modules.order file
 343#
 344# Create commands to either record .ko file or cat modules.order from
 345# a subdirectory
 346modorder-cmds =                                         \
 347        $(foreach m, $(modorder),                       \
 348                $(if $(filter %/modules.order, $m),     \
 349                        cat $m;, echo kernel/$m;))
 350
 351$(modorder-target): $(subdir-ym) FORCE
 352        $(Q)(cat /dev/null; $(modorder-cmds)) > $@
 353
 354#
 355# Rule to compile a set of .o files into one .a file
 356#
 357ifdef lib-target
 358quiet_cmd_link_l_target = AR      $@
 359cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
 360
 361$(lib-target): $(lib-y) FORCE
 362        $(call if_changed,link_l_target)
 363
 364targets += $(lib-target)
 365endif
 366
 367#
 368# Rule to link composite objects
 369#
 370#  Composite objects are specified in kbuild makefile as follows:
 371#    <composite-object>-objs := <list of .o files>
 372#  or
 373#    <composite-object>-y    := <list of .o files>
 374link_multi_deps =                     \
 375$(filter $(addprefix $(obj)/,         \
 376$($(subst $(obj)/,,$(@:.o=-objs)))    \
 377$($(subst $(obj)/,,$(@:.o=-y)))), $^)
 378
 379quiet_cmd_link_multi-y = LD      $@
 380cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
 381
 382quiet_cmd_link_multi-m = LD [M]  $@
 383cmd_link_multi-m = $(cmd_link_multi-y)
 384
 385$(multi-used-y): FORCE
 386        $(call if_changed,link_multi-y)
 387$(call multi_depend, $(multi-used-y), .o, -objs -y)
 388
 389$(multi-used-m): FORCE
 390        $(call if_changed,link_multi-m)
 391        @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod)
 392$(call multi_depend, $(multi-used-m), .o, -objs -y)
 393
 394targets += $(multi-used-y) $(multi-used-m)
 395
 396
 397# Descending
 398# ---------------------------------------------------------------------------
 399
 400PHONY += $(subdir-ym)
 401$(subdir-ym):
 402        $(Q)$(MAKE) $(build)=$@
 403
 404# Add FORCE to the prequisites of a target to force it to be always rebuilt.
 405# ---------------------------------------------------------------------------
 406
 407PHONY += FORCE
 408
 409FORCE:
 410
 411# Read all saved command lines and dependencies for the $(targets) we
 412# may be building above, using $(if_changed{,_dep}). As an
 413# optimization, we don't need to read them if the target does not
 414# exist, we will rebuild anyway in that case.
 415
 416targets := $(wildcard $(sort $(targets)))
 417cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 418
 419ifneq ($(cmd_files),)
 420  include $(cmd_files)
 421endif
 422
 423# Declare the contents of the .PHONY variable as phony.  We keep that
 424# information in a variable se we can use it in if_changed and friends.
 425
 426.PHONY: $(PHONY)
 427
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.