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-rw-r--r--scripts/Makefile.build579
1 files changed, 579 insertions, 0 deletions
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
new file mode 100644
index 000000000..64fac0ad3
--- /dev/null
+++ b/scripts/Makefile.build
@@ -0,0 +1,579 @@
+# SPDX-License-Identifier: GPL-2.0
+# ==========================================================================
+# Building
+# ==========================================================================
+
+src := $(obj)
+
+PHONY := __build
+__build:
+
+# Init all relevant variables used in kbuild files so
+# 1) they have correct type
+# 2) they do not inherit any value from the environment
+obj-y :=
+obj-m :=
+lib-y :=
+lib-m :=
+always :=
+targets :=
+subdir-y :=
+subdir-m :=
+EXTRA_AFLAGS :=
+EXTRA_CFLAGS :=
+EXTRA_CPPFLAGS :=
+EXTRA_LDFLAGS :=
+asflags-y :=
+ccflags-y :=
+cppflags-y :=
+ldflags-y :=
+
+subdir-asflags-y :=
+subdir-ccflags-y :=
+
+# Read auto.conf if it exists, otherwise ignore
+-include include/config/auto.conf
+
+include scripts/Kbuild.include
+
+# For backward compatibility check that these variables do not change
+save-cflags := $(CFLAGS)
+
+# The filename Kbuild has precedence over Makefile
+kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
+kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
+include $(kbuild-file)
+
+# If the save-* variables changed error out
+ifeq ($(KBUILD_NOPEDANTIC),)
+ ifneq ("$(save-cflags)","$(CFLAGS)")
+ $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
+ endif
+endif
+
+include scripts/Makefile.lib
+
+# Do not include host rules unless needed
+ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
+include scripts/Makefile.host
+endif
+
+ifndef obj
+$(warning kbuild: Makefile.build is included improperly)
+endif
+
+# ===========================================================================
+
+ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
+lib-target := $(obj)/lib.a
+real-obj-y += $(obj)/lib-ksyms.o
+endif
+
+ifneq ($(strip $(real-obj-y) $(need-builtin)),)
+builtin-target := $(obj)/built-in.a
+endif
+
+modorder-target := $(obj)/modules.order
+
+# We keep a list of all modules in $(MODVERDIR)
+
+__build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
+ $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
+ $(subdir-ym) $(always)
+ @:
+
+# Linus' kernel sanity checking tool
+ifneq ($(KBUILD_CHECKSRC),0)
+ ifeq ($(KBUILD_CHECKSRC),2)
+ quiet_cmd_force_checksrc = CHECK $<
+ cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
+ else
+ quiet_cmd_checksrc = CHECK $<
+ cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
+ endif
+endif
+
+ifneq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),)
+ cmd_checkdoc = $(srctree)/scripts/kernel-doc -none $< ;
+endif
+
+# Do section mismatch analysis for each module/built-in.a
+ifdef CONFIG_DEBUG_SECTION_MISMATCH
+ cmd_secanalysis = ; scripts/mod/modpost $@
+endif
+
+# Compile C sources (.c)
+# ---------------------------------------------------------------------------
+
+# Default is built-in, unless we know otherwise
+modkern_cflags = \
+ $(if $(part-of-module), \
+ $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
+ $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
+quiet_modtag := $(empty) $(empty)
+
+$(real-obj-m) : part-of-module := y
+$(real-obj-m:.o=.i) : part-of-module := y
+$(real-obj-m:.o=.s) : part-of-module := y
+$(real-obj-m:.o=.lst): part-of-module := y
+
+$(real-obj-m) : quiet_modtag := [M]
+$(real-obj-m:.o=.i) : quiet_modtag := [M]
+$(real-obj-m:.o=.s) : quiet_modtag := [M]
+$(real-obj-m:.o=.lst): quiet_modtag := [M]
+
+$(obj-m) : quiet_modtag := [M]
+
+quiet_cmd_cc_s_c = CC $(quiet_modtag) $@
+cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
+
+$(obj)/%.s: $(src)/%.c FORCE
+ $(call if_changed_dep,cc_s_c)
+
+quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
+cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $<
+
+$(obj)/%.i: $(src)/%.c FORCE
+ $(call if_changed_dep,cpp_i_c)
+
+# These mirror gensymtypes_S and co below, keep them in synch.
+cmd_gensymtypes_c = \
+ $(CPP) -D__GENKSYMS__ $(c_flags) $< | \
+ $(GENKSYMS) $(if $(1), -T $(2)) \
+ $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS)) \
+ $(if $(KBUILD_PRESERVE),-p) \
+ -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
+
+quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
+cmd_cc_symtypes_c = \
+ set -e; \
+ $(call cmd_gensymtypes_c,true,$@) >/dev/null; \
+ test -s $@ || rm -f $@
+
+$(obj)/%.symtypes : $(src)/%.c FORCE
+ $(call cmd,cc_symtypes_c)
+
+# LLVM assembly
+# Generate .ll files from .c
+quiet_cmd_cc_ll_c = CC $(quiet_modtag) $@
+ cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
+
+$(obj)/%.ll: $(src)/%.c FORCE
+ $(call if_changed_dep,cc_ll_c)
+
+# C (.c) files
+# The C file is compiled and updated dependency information is generated.
+# (See cmd_cc_o_c + relevant part of rule_cc_o_c)
+
+quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
+
+ifndef CONFIG_MODVERSIONS
+cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
+
+else
+# When module versioning is enabled the following steps are executed:
+# o compile a .tmp_<file>.o from <file>.c
+# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
+# not export symbols, we just rename .tmp_<file>.o to <file>.o and
+# are done.
+# o otherwise, we calculate symbol versions using the good old
+# genksyms on the preprocessed source and postprocess them in a way
+# that they are usable as a linker script
+# o generate <file>.o from .tmp_<file>.o using the linker to
+# replace the unresolved symbols __crc_exported_symbol with
+# the actual value of the checksum generated by genksyms
+
+cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
+
+cmd_modversions_c = \
+ if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
+ $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
+ > $(@D)/.tmp_$(@F:.o=.ver); \
+ \
+ $(LD) $(KBUILD_LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
+ -T $(@D)/.tmp_$(@F:.o=.ver); \
+ rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
+ else \
+ mv -f $(@D)/.tmp_$(@F) $@; \
+ fi;
+endif
+
+ifdef CONFIG_FTRACE_MCOUNT_RECORD
+ifndef CC_USING_RECORD_MCOUNT
+# compiler will not generate __mcount_loc use recordmcount or recordmcount.pl
+ifdef BUILD_C_RECORDMCOUNT
+ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
+ RECORDMCOUNT_FLAGS = -w
+endif
+# Due to recursion, we must skip empty.o.
+# The empty.o file is created in the make process in order to determine
+# the target endianness and word size. It is made before all other C
+# files, including recordmcount.
+sub_cmd_record_mcount = \
+ if [ $(@) != "scripts/mod/empty.o" ]; then \
+ $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \
+ fi;
+recordmcount_source := $(srctree)/scripts/recordmcount.c \
+ $(srctree)/scripts/recordmcount.h
+else
+sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
+ "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
+ "$(if $(CONFIG_64BIT),64,32)" \
+ "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS)" \
+ "$(LD) $(KBUILD_LDFLAGS)" "$(NM)" "$(RM)" "$(MV)" \
+ "$(if $(part-of-module),1,0)" "$(@)";
+recordmcount_source := $(srctree)/scripts/recordmcount.pl
+endif # BUILD_C_RECORDMCOUNT
+cmd_record_mcount = \
+ if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" = \
+ "$(CC_FLAGS_FTRACE)" ]; then \
+ $(sub_cmd_record_mcount) \
+ fi;
+endif # CC_USING_RECORD_MCOUNT
+endif # CONFIG_FTRACE_MCOUNT_RECORD
+
+ifdef CONFIG_STACK_VALIDATION
+ifneq ($(SKIP_STACK_VALIDATION),1)
+
+__objtool_obj := $(objtree)/tools/objtool/objtool
+
+objtool_args = $(if $(CONFIG_UNWINDER_ORC),orc generate,check)
+
+objtool_args += $(if $(part-of-module), --module,)
+
+ifndef CONFIG_FRAME_POINTER
+objtool_args += --no-fp
+endif
+ifdef CONFIG_GCOV_KERNEL
+objtool_args += --no-unreachable
+endif
+ifdef CONFIG_RETPOLINE
+ objtool_args += --retpoline
+endif
+
+
+ifdef CONFIG_MODVERSIONS
+objtool_o = $(@D)/.tmp_$(@F)
+else
+objtool_o = $(@)
+endif
+
+# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
+# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
+# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
+cmd_objtool = $(if $(patsubst y%,, \
+ $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
+ $(__objtool_obj) $(objtool_args) "$(objtool_o)";)
+objtool_obj = $(if $(patsubst y%,, \
+ $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
+ $(__objtool_obj))
+
+endif # SKIP_STACK_VALIDATION
+endif # CONFIG_STACK_VALIDATION
+
+# Rebuild all objects when objtool changes, or is enabled/disabled.
+objtool_dep = $(objtool_obj) \
+ $(wildcard include/config/orc/unwinder.h \
+ include/config/stack/validation.h)
+
+define rule_cc_o_c
+ $(call echo-cmd,checksrc) $(cmd_checksrc) \
+ $(call cmd_and_fixdep,cc_o_c) \
+ $(cmd_checkdoc) \
+ $(call echo-cmd,objtool) $(cmd_objtool) \
+ $(cmd_modversions_c) \
+ $(call echo-cmd,record_mcount) $(cmd_record_mcount)
+endef
+
+define rule_as_o_S
+ $(call cmd_and_fixdep,as_o_S) \
+ $(call echo-cmd,objtool) $(cmd_objtool) \
+ $(cmd_modversions_S)
+endef
+
+# List module undefined symbols (or empty line if not enabled)
+ifdef CONFIG_TRIM_UNUSED_KSYMS
+cmd_undef_syms = $(NM) $@ | sed -n 's/^ *U //p' | xargs echo
+else
+cmd_undef_syms = echo
+endif
+
+# Built-in and composite module parts
+$(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
+ $(call cmd,force_checksrc)
+ $(call if_changed_rule,cc_o_c)
+
+# Single-part modules are special since we need to mark them in $(MODVERDIR)
+
+$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
+ $(call cmd,force_checksrc)
+ $(call if_changed_rule,cc_o_c)
+ @{ echo $(@:.o=.ko); echo $@; \
+ $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
+
+quiet_cmd_cc_lst_c = MKLST $@
+ cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
+ $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
+ System.map $(OBJDUMP) > $@
+
+$(obj)/%.lst: $(src)/%.c FORCE
+ $(call if_changed_dep,cc_lst_c)
+
+# Compile assembler sources (.S)
+# ---------------------------------------------------------------------------
+
+modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
+
+$(real-obj-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
+$(real-obj-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
+
+# .S file exports must have their C prototypes defined in asm/asm-prototypes.h
+# or a file that it includes, in order to get versioned symbols. We build a
+# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
+# the .S file (with trailing ';'), and run genksyms on that, to extract vers.
+#
+# This is convoluted. The .S file must first be preprocessed to run guards and
+# expand names, then the resulting exports must be constructed into plain
+# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
+# to make the genksyms input.
+#
+# These mirror gensymtypes_c and co above, keep them in synch.
+cmd_gensymtypes_S = \
+ (echo "\#include <linux/kernel.h>" ; \
+ echo "\#include <asm/asm-prototypes.h>" ; \
+ $(CPP) $(a_flags) $< | \
+ grep "\<___EXPORT_SYMBOL\>" | \
+ sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
+ $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | \
+ $(GENKSYMS) $(if $(1), -T $(2)) \
+ $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS)) \
+ $(if $(KBUILD_PRESERVE),-p) \
+ -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
+
+quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
+cmd_cc_symtypes_S = \
+ set -e; \
+ $(call cmd_gensymtypes_S,true,$@) >/dev/null; \
+ test -s $@ || rm -f $@
+
+$(obj)/%.symtypes : $(src)/%.S FORCE
+ $(call cmd,cc_symtypes_S)
+
+
+quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
+cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $<
+
+$(obj)/%.s: $(src)/%.S FORCE
+ $(call if_changed_dep,cpp_s_S)
+
+quiet_cmd_as_o_S = AS $(quiet_modtag) $@
+
+ifndef CONFIG_MODVERSIONS
+cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
+
+else
+
+ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
+
+ifeq ($(ASM_PROTOTYPES),)
+cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
+
+else
+
+# versioning matches the C process described above, with difference that
+# we parse asm-prototypes.h C header to get function definitions.
+
+cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
+
+cmd_modversions_S = \
+ if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
+ $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
+ > $(@D)/.tmp_$(@F:.o=.ver); \
+ \
+ $(LD) $(KBUILD_LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
+ -T $(@D)/.tmp_$(@F:.o=.ver); \
+ rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
+ else \
+ mv -f $(@D)/.tmp_$(@F) $@; \
+ fi;
+endif
+endif
+
+$(obj)/%.o: $(src)/%.S $(objtool_dep) FORCE
+ $(call if_changed_rule,as_o_S)
+
+targets += $(filter-out $(subdir-obj-y), $(real-obj-y)) $(real-obj-m) $(lib-y)
+targets += $(extra-y) $(MAKECMDGOALS) $(always)
+
+# Linker scripts preprocessor (.lds.S -> .lds)
+# ---------------------------------------------------------------------------
+quiet_cmd_cpp_lds_S = LDS $@
+ cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -U$(ARCH) \
+ -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
+
+$(obj)/%.lds: $(src)/%.lds.S FORCE
+ $(call if_changed_dep,cpp_lds_S)
+
+# ASN.1 grammar
+# ---------------------------------------------------------------------------
+quiet_cmd_asn1_compiler = ASN.1 $@
+ cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
+ $(subst .h,.c,$@) $(subst .c,.h,$@)
+
+$(obj)/%.asn1.c $(obj)/%.asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
+ $(call cmd,asn1_compiler)
+
+# Build the compiled-in targets
+# ---------------------------------------------------------------------------
+
+# To build objects in subdirs, we need to descend into the directories
+$(sort $(subdir-obj-y)): $(subdir-ym) ;
+
+#
+# Rule to compile a set of .o files into one .o file
+#
+ifdef builtin-target
+
+# built-in.a archives are made with no symbol table or index which
+# makes them small and fast, but unable to be used by the linker.
+# scripts/link-vmlinux.sh builds an aggregate built-in.a with a symbol
+# table and index.
+quiet_cmd_ar_builtin = AR $@
+ cmd_ar_builtin = rm -f $@; \
+ $(AR) rcSTP$(KBUILD_ARFLAGS) $@ $(filter $(real-obj-y), $^)
+
+$(builtin-target): $(real-obj-y) FORCE
+ $(call if_changed,ar_builtin)
+
+targets += $(builtin-target)
+endif # builtin-target
+
+#
+# Rule to create modules.order file
+#
+# Create commands to either record .ko file or cat modules.order from
+# a subdirectory
+modorder-cmds = \
+ $(foreach m, $(modorder), \
+ $(if $(filter %/modules.order, $m), \
+ cat $m;, echo kernel/$m;))
+
+$(modorder-target): $(subdir-ym) FORCE
+ $(Q)(cat /dev/null; $(modorder-cmds)) > $@
+
+#
+# Rule to compile a set of .o files into one .a file
+#
+ifdef lib-target
+quiet_cmd_link_l_target = AR $@
+
+# lib target archives do get a symbol table and index
+cmd_link_l_target = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(lib-y)
+
+$(lib-target): $(lib-y) FORCE
+ $(call if_changed,link_l_target)
+
+targets += $(lib-target)
+
+dummy-object = $(obj)/.lib_exports.o
+ksyms-lds = $(dot-target).lds
+
+quiet_cmd_export_list = EXPORTS $@
+cmd_export_list = $(OBJDUMP) -h $< | \
+ sed -ne '/___ksymtab/s/.*+\([^ ]*\).*/EXTERN(\1)/p' >$(ksyms-lds);\
+ rm -f $(dummy-object);\
+ echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\
+ $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
+ rm $(dummy-object) $(ksyms-lds)
+
+$(obj)/lib-ksyms.o: $(lib-target) FORCE
+ $(call if_changed,export_list)
+
+targets += $(obj)/lib-ksyms.o
+
+endif
+
+#
+# Rule to link composite objects
+#
+# Composite objects are specified in kbuild makefile as follows:
+# <composite-object>-objs := <list of .o files>
+# or
+# <composite-object>-y := <list of .o files>
+# or
+# <composite-object>-m := <list of .o files>
+# The -m syntax only works if <composite object> is a module
+link_multi_deps = \
+$(filter $(addprefix $(obj)/, \
+$($(subst $(obj)/,,$(@:.o=-objs))) \
+$($(subst $(obj)/,,$(@:.o=-y))) \
+$($(subst $(obj)/,,$(@:.o=-m)))), $^)
+
+quiet_cmd_link_multi-m = LD [M] $@
+cmd_link_multi-m = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
+
+$(multi-used-m): FORCE
+ $(call if_changed,link_multi-m)
+ @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
+ $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
+$(call multi_depend, $(multi-used-m), .o, -objs -y -m)
+
+targets += $(multi-used-m)
+targets := $(filter-out $(PHONY), $(targets))
+
+# Add intermediate targets:
+# When building objects with specific suffix patterns, add intermediate
+# targets that the final targets are derived from.
+intermediate_targets = $(foreach sfx, $(2), \
+ $(patsubst %$(strip $(1)),%$(sfx), \
+ $(filter %$(strip $(1)), $(targets))))
+# %.asn1.o <- %.asn1.[ch] <- %.asn1
+# %.dtb.o <- %.dtb.S <- %.dtb <- %.dts
+# %.lex.o <- %.lex.c <- %.l
+# %.tab.o <- %.tab.[ch] <- %.y
+targets += $(call intermediate_targets, .asn1.o, .asn1.c .asn1.h) \
+ $(call intermediate_targets, .dtb.o, .dtb.S .dtb) \
+ $(call intermediate_targets, .lex.o, .lex.c) \
+ $(call intermediate_targets, .tab.o, .tab.c .tab.h)
+
+# Descending
+# ---------------------------------------------------------------------------
+
+PHONY += $(subdir-ym)
+$(subdir-ym):
+ $(Q)$(MAKE) $(build)=$@ need-builtin=$(if $(findstring $@,$(subdir-obj-y)),1)
+
+# Add FORCE to the prequisites of a target to force it to be always rebuilt.
+# ---------------------------------------------------------------------------
+
+PHONY += FORCE
+
+FORCE:
+
+# Read all saved command lines and dependencies for the $(targets) we
+# may be building above, using $(if_changed{,_dep}). As an
+# optimization, we don't need to read them if the target does not
+# exist, we will rebuild anyway in that case.
+
+cmd_files := $(wildcard $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd))
+
+ifneq ($(cmd_files),)
+ include $(cmd_files)
+endif
+
+ifneq ($(KBUILD_SRC),)
+# Create directories for object files if they do not exist
+obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets))))
+# If cmd_files exist, their directories apparently exist. Skip mkdir.
+exist-dirs := $(sort $(patsubst %/,%, $(dir $(cmd_files))))
+obj-dirs := $(strip $(filter-out $(exist-dirs), $(obj-dirs)))
+ifneq ($(obj-dirs),)
+$(shell mkdir -p $(obj-dirs))
+endif
+endif
+
+# Some files contained in $(targets) are intermediate artifacts.
+# We never want them to be removed automatically.
+.SECONDARY: $(targets)
+
+.PHONY: $(PHONY)