1# SPDX-License-Identifier: GPL-2.0 2# ========================================================================== 3# Building 4# ========================================================================== 5 6src := $(srcroot)/$(obj) 7 8PHONY := $(obj)/ 9$(obj)/: 10 11# Init all relevant variables used in kbuild files so 12# 1) they have correct type 13# 2) they do not inherit any value from the environment 14obj-y := 15obj-m := 16lib-y := 17lib-m := 18always-y := 19always-m := 20targets := 21subdir-y := 22subdir-m := 23asflags-y := 24ccflags-y := 25rustflags-y := 26cppflags-y := 27ldflags-y := 28 29subdir-asflags-y := 30subdir-ccflags-y := 31 32# Read auto.conf if it exists, otherwise ignore 33-include $(objtree)/include/config/auto.conf 34 35include $(srctree)/scripts/Kbuild.include 36include $(srctree)/scripts/Makefile.compiler 37include $(kbuild-file) 38include $(srctree)/scripts/Makefile.lib 39 40# flags that take effect in current and sub directories 41KBUILD_AFLAGS += $(subdir-asflags-y) 42KBUILD_CFLAGS += $(subdir-ccflags-y) 43KBUILD_RUSTFLAGS += $(subdir-rustflags-y) 44 45# Figure out what we need to build from the various variables 46# =========================================================================== 47 48# When an object is listed to be built compiled-in and modular, 49# only build the compiled-in version 50obj-m := $(filter-out $(obj-y),$(obj-m)) 51 52# Libraries are always collected in one lib file. 53# Filter out objects already built-in 54lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m))) 55 56# Subdirectories we need to descend into 57subdir-ym := $(sort $(subdir-y) $(subdir-m) \ 58 $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m)))) 59 60# Handle objects in subdirs: 61# - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and 62# foo/modules.order 63# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order 64# 65# Generate modules.order to determine modorder. Unfortunately, we don't have 66# information about ordering between -y and -m subdirs. Just put -y's first. 67 68ifdef need-modorder 69obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m)) 70else 71obj-m := $(filter-out %/, $(obj-m)) 72endif 73 74ifdef need-builtin 75obj-y := $(patsubst %/, %/built-in.a, $(obj-y)) 76else 77obj-y := $(filter-out %/, $(obj-y)) 78endif 79 80# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals 81suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s)))) 82# List composite targets that are constructed by combining other targets 83multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m))) 84# List primitive targets that are compiled from source files 85real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m)) 86 87# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object 88multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y) 89multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m) 90multi-obj-ym := $(multi-obj-y) $(multi-obj-m) 91 92# Replace multi-part objects by their individual parts, 93# including built-in.a from subdirectories 94real-obj-y := $(call real-search, $(obj-y), .o, -objs -y) 95real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m) 96 97always-y += $(always-m) 98 99# hostprogs-always-y += foo 100# ... is a shorthand for 101# hostprogs += foo 102# always-y += foo 103hostprogs += $(hostprogs-always-y) $(hostprogs-always-m) 104always-y += $(hostprogs-always-y) $(hostprogs-always-m) 105 106# userprogs-always-y is likewise. 107userprogs += $(userprogs-always-y) $(userprogs-always-m) 108always-y += $(userprogs-always-y) $(userprogs-always-m) 109 110# Add subdir path 111 112ifneq ($(obj),.) 113extra-y := $(addprefix $(obj)/, $(extra-y)) 114always-y := $(addprefix $(obj)/, $(always-y)) 115targets := $(addprefix $(obj)/, $(targets)) 116obj-m := $(addprefix $(obj)/, $(obj-m)) 117lib-y := $(addprefix $(obj)/, $(lib-y)) 118real-obj-y := $(addprefix $(obj)/, $(real-obj-y)) 119real-obj-m := $(addprefix $(obj)/, $(real-obj-m)) 120multi-obj-m := $(addprefix $(obj)/, $(multi-obj-m)) 121subdir-ym := $(addprefix $(obj)/, $(subdir-ym)) 122endif 123 124ifndef obj 125$(warning kbuild: Makefile.build is included improperly) 126endif 127 128ifeq ($(need-modorder),) 129ifneq ($(obj-m),) 130$(warning $(patsubst %.o,'%.ko',$(obj-m)) will not be built even though obj-m is specified.) 131$(warning You cannot use subdir-y/m to visit a module Makefile. Use obj-y/m instead.) 132endif 133endif 134 135# =========================================================================== 136 137# subdir-builtin and subdir-modorder may contain duplications. Use $(sort ...) 138subdir-builtin := $(sort $(filter %/built-in.a, $(real-obj-y))) 139subdir-modorder := $(sort $(filter %/modules.order, $(obj-m))) 140 141targets-for-builtin := $(extra-y) 142 143ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),) 144targets-for-builtin += $(obj)/lib.a 145endif 146 147ifdef need-builtin 148targets-for-builtin += $(obj)/built-in.a 149endif 150 151targets-for-modules := $(foreach x, o mod, \ 152 $(patsubst %.o, %.$x, $(filter %.o, $(obj-m)))) 153 154ifdef need-modorder 155targets-for-modules += $(obj)/modules.order 156endif 157 158targets += $(targets-for-builtin) $(targets-for-modules) 159 160# Linus' kernel sanity checking tool 161ifeq ($(KBUILD_CHECKSRC),1) 162 quiet_cmd_checksrc = CHECK $< 163 cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< 164else ifeq ($(KBUILD_CHECKSRC),2) 165 quiet_cmd_force_checksrc = CHECK $< 166 cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< 167endif 168 169ifeq ($(KBUILD_EXTMOD),) 170ifneq ($(KBUILD_EXTRA_WARN),) 171 cmd_checkdoc = PYTHONDONTWRITEBYTECODE=1 $(PYTHON3) $(KERNELDOC) -none $(KDOCFLAGS) \ 172 $(if $(findstring 2, $(KBUILD_EXTRA_WARN)), -Wall) \ 173 $< 174endif 175endif 176 177# Compile C sources (.c) 178# --------------------------------------------------------------------------- 179 180quiet_cmd_cc_s_c = CC $(quiet_modtag) $@ 181 cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS) $(CC_FLAGS_LTO), $(c_flags)) -fverbose-asm -S -o $@ $< 182 183$(obj)/%.s: $(obj)/%.c FORCE 184 $(call if_changed_dep,cc_s_c) 185 186quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@ 187cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $< 188 189$(obj)/%.i: $(obj)/%.c FORCE 190 $(call if_changed_dep,cpp_i_c) 191 192getexportsymbols = $(NM) $@ | sed -n 's/.* __export_symbol_\(.*\)/$(1)/p' 193 194gendwarfksyms = $(objtree)/scripts/gendwarfksyms/gendwarfksyms \ 195 $(if $(KBUILD_SYMTYPES), --symtypes $(@:.o=.symtypes)) \ 196 $(if $(KBUILD_GENDWARFKSYMS_STABLE), --stable) 197 198genksyms = $(objtree)/scripts/genksyms/genksyms \ 199 $(if $(KBUILD_SYMTYPES), -T $(@:.o=.symtypes)) \ 200 $(if $(KBUILD_PRESERVE), -p) \ 201 $(addprefix -r , $(wildcard $(@:.o=.symref))) 202 203# These mirror gensymtypes_S and co below, keep them in synch. 204ifdef CONFIG_GENDWARFKSYMS 205cmd_gensymtypes_c = $(if $(skip_gendwarfksyms),, \ 206 $(call getexportsymbols,\1) | $(gendwarfksyms) $@) 207else 208cmd_gensymtypes_c = $(CPP) -D__GENKSYMS__ $(c_flags) $< | $(genksyms) 209endif # CONFIG_GENDWARFKSYMS 210 211# LLVM assembly 212# Generate .ll files from .c 213quiet_cmd_cc_ll_c = CC $(quiet_modtag) $@ 214 cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -fno-discard-value-names -o $@ $< 215 216$(obj)/%.ll: $(obj)/%.c FORCE 217 $(call if_changed_dep,cc_ll_c) 218 219# C (.c) files 220# The C file is compiled and updated dependency information is generated. 221# (See cmd_cc_o_c + relevant part of rule_cc_o_c) 222 223is-single-obj-m = $(and $(part-of-module),$(filter $@, $(obj-m)),y) 224 225ifdef CONFIG_MODVERSIONS 226# When module versioning is enabled the following steps are executed: 227# o compile a <file>.o from <file>.c 228# o if <file>.o doesn't contain a __export_symbol_*, i.e. does 229# not export symbols, it's done. 230# o otherwise, we calculate symbol versions using the good old 231# genksyms on the preprocessed source and dump them into the .cmd file. 232# o modpost will extract versions from that file and create *.c files that will 233# be compiled and linked to the kernel and/or modules. 234 235gen_symversions = \ 236 if $(NM) $@ 2>/dev/null | grep -q ' __export_symbol_'; then \ 237 $(cmd_gensymtypes_$1) >> $(dot-target).cmd; \ 238 fi 239 240cmd_gen_symversions_c = $(call gen_symversions,c) 241 242endif 243 244ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT 245# compiler will not generate __mcount_loc use recordmcount or recordmcount.pl 246ifdef BUILD_C_RECORDMCOUNT 247ifeq ("$(origin RECORDMCOUNT_WARN)", "command line") 248 RECORDMCOUNT_FLAGS = -w 249endif 250# Due to recursion, we must skip empty.o. 251# The empty.o file is created in the make process in order to determine 252# the target endianness and word size. It is made before all other C 253# files, including recordmcount. 254sub_cmd_record_mcount = \ 255 if [ $(@) != "scripts/mod/empty.o" ]; then \ 256 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \ 257 fi; 258recordmcount_source := $(srctree)/scripts/recordmcount.c \ 259 $(srctree)/scripts/recordmcount.h 260else 261sub_cmd_record_mcount = perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \ 262 "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \ 263 "$(if $(CONFIG_64BIT),64,32)" \ 264 "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS)" \ 265 "$(LD) $(KBUILD_LDFLAGS)" "$(NM)" "$(RM)" "$(MV)" \ 266 "$(if $(part-of-module),1,0)" "$(@)"; 267recordmcount_source := $(srctree)/scripts/recordmcount.pl 268endif # BUILD_C_RECORDMCOUNT 269cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)), \ 270 $(sub_cmd_record_mcount)) 271endif # CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT 272 273# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory 274# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file 275# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file 276 277is-standard-object = $(if $(filter-out y%, $(OBJECT_FILES_NON_STANDARD_$(target-stem).o)$(OBJECT_FILES_NON_STANDARD)n),$(is-kernel-object)) 278 279ifdef CONFIG_OBJTOOL 280$(obj)/%.o: private objtool-enabled = $(if $(is-standard-object),$(if $(delay-objtool),$(is-single-obj-m),y)) 281endif 282 283ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) 284cmd_warn_shared_object = $(if $(word 2, $(modname-multi)),$(warning $(kbuild-file): $*.o is added to multiple modules: $(modname-multi))) 285endif 286 287# Built-in and composite module parts 288$(obj)/%.o: $(obj)/%.c $(recordmcount_source) FORCE 289 $(call if_changed_rule,cc_o_c) 290 $(call cmd,force_checksrc) 291 292# To make this rule robust against "Argument list too long" error, 293# ensure to add $(obj)/ prefix by a shell command. 294cmd_mod = printf '%s\n' $(call real-search, $*.o, .o, -objs -y -m) | \ 295 $(AWK) '!x[$$0]++ { print("$(obj)/"$$0) }' > $@ 296 297$(obj)/%.mod: FORCE 298 $(call if_changed,mod) 299 300quiet_cmd_cc_lst_c = MKLST $@ 301 cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \ 302 $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \ 303 System.map $(OBJDUMP) > $@ 304 305$(obj)/%.lst: $(obj)/%.c FORCE 306 $(call if_changed_dep,cc_lst_c) 307 308# Compile Rust sources (.rs) 309# --------------------------------------------------------------------------- 310 311# The features in this list are the ones allowed for non-`rust/` code. 312# 313# - Stable since Rust 1.79.0: `feature(inline_const)`. 314# - Stable since Rust 1.81.0: `feature(lint_reasons)`. 315# - Stable since Rust 1.82.0: `feature(asm_const)`, 316# `feature(offset_of_nested)`, `feature(raw_ref_op)`. 317# - Stable since Rust 1.87.0: `feature(asm_goto)`. 318# - Expected to become stable: `feature(arbitrary_self_types)`. 319# - To be determined: `feature(used_with_arg)`. 320# 321# Please see https://github.com/Rust-for-Linux/linux/issues/2 for details on 322# the unstable features in use. 323rust_allowed_features := asm_const,asm_goto,arbitrary_self_types,inline_const,lint_reasons,offset_of_nested,raw_ref_op,used_with_arg 324 325# `--out-dir` is required to avoid temporaries being created by `rustc` in the 326# current working directory, which may be not accessible in the out-of-tree 327# modules case. 328rust_common_cmd = \ 329 OBJTREE=$(abspath $(objtree)) \ 330 RUST_MODFILE=$(modfile) $(RUSTC_OR_CLIPPY) $(rust_flags) \ 331 -Zallow-features=$(rust_allowed_features) \ 332 -Zcrate-attr=no_std \ 333 -Zcrate-attr='feature($(rust_allowed_features))' \ 334 -Zunstable-options --extern pin_init --extern kernel \ 335 --crate-type rlib -L $(objtree)/rust/ \ 336 --sysroot=/dev/null \ 337 --out-dir $(dir $@) --emit=dep-info=$(depfile) 338 339# `--emit=obj`, `--emit=asm` and `--emit=llvm-ir` imply a single codegen unit 340# will be used. We explicitly request `-Ccodegen-units=1` in any case, and 341# the compiler shows a warning if it is not 1. However, if we ever stop 342# requesting it explicitly and we start using some other `--emit` that does not 343# imply it (and for which codegen is performed), then we would be out of sync, 344# i.e. the outputs we would get for the different single targets (e.g. `.ll`) 345# would not match each other. 346 347quiet_cmd_rustc_o_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ 348 cmd_rustc_o_rs = $(rust_common_cmd) --emit=$(if $(CONFIG_RUST_INLINE_HELPERS),llvm-bc=$(patsubst %.o,%.bc,$@),obj=$@) $< \ 349 $(if $(CONFIG_RUST_INLINE_HELPERS),;$(LLVM_LINK) --internalize --suppress-warnings $(patsubst %.o,%.bc,$@) \ 350 $(objtree)/rust/helpers/helpers$(if $(part-of-module),_module).bc -o $(patsubst %.o,%.m.bc,$@); \ 351 $(CC) $(CLANG_FLAGS) $(KBUILD_CFLAGS) -Wno-override-module -c $(patsubst %.o,%.m.bc,$@) -o $@ \ 352 $(cmd_ld_single)) \ 353 $(cmd_objtool) 354 355define rule_rustc_o_rs 356 $(call cmd_and_fixdep,rustc_o_rs) 357 $(call cmd,gen_objtooldep) 358endef 359 360$(obj)/%.o: $(obj)/%.rs FORCE 361 +$(call if_changed_rule,rustc_o_rs) 362 363quiet_cmd_rustc_rsi_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ 364 cmd_rustc_rsi_rs = \ 365 $(rust_common_cmd) -Zunpretty=expanded $< >$@; \ 366 command -v $(RUSTFMT) >/dev/null && $(RUSTFMT) --config-path $(srctree)/.rustfmt.toml $@ 367 368$(obj)/%.rsi: $(obj)/%.rs FORCE 369 +$(call if_changed_dep,rustc_rsi_rs) 370 371quiet_cmd_rustc_s_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ 372 cmd_rustc_s_rs = $(rust_common_cmd) --emit=asm=$@ $< 373 374$(obj)/%.s: $(obj)/%.rs FORCE 375 +$(call if_changed_dep,rustc_s_rs) 376 377quiet_cmd_rustc_ll_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ 378 cmd_rustc_ll_rs = $(rust_common_cmd) --emit=llvm-ir=$@ $< 379 380$(obj)/%.ll: $(obj)/%.rs FORCE 381 +$(call if_changed_dep,rustc_ll_rs) 382 383quiet_cmd_rustc_rs_rs_S = RSCPP $(quiet_modtag) $@ 384 cmd_rustc_rs_rs_S = $(CPP) $(c_flags) -xc -C -P $< | sed '1,/^\/\/ Cut here.$$/d' >$@ 385 386$(obj)/%.rs: $(obj)/%.rs.S FORCE 387 +$(call if_changed_dep,rustc_rs_rs_S) 388 389# Compile assembler sources (.S) 390# --------------------------------------------------------------------------- 391 392# .S file exports must have their C prototypes defined in asm/asm-prototypes.h 393# or a file that it includes, in order to get versioned symbols. We build a 394# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from 395# the .S file (with trailing ';'), and run genksyms on that, to extract vers. 396# 397# This is convoluted. The .S file must first be preprocessed to run guards and 398# expand names, then the resulting exports must be constructed into plain 399# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed 400# to make the genksyms input or compiled into an object for gendwarfksyms. 401# 402# These mirror gensymtypes_c and co above, keep them in synch. 403getasmexports = \ 404 { echo "\#include <linux/kernel.h>" ; \ 405 echo "\#include <linux/string.h>" ; \ 406 echo "\#include <asm/asm-prototypes.h>" ; \ 407 $(call getexportsymbols,EXPORT_SYMBOL(\1);) ; } 408 409ifdef CONFIG_GENDWARFKSYMS 410cmd_gensymtypes_S = \ 411 $(getasmexports) | \ 412 $(CC) $(c_flags) -c -o $(@:.o=.gendwarfksyms.o) -xc -; \ 413 $(call getexportsymbols,\1) | \ 414 $(gendwarfksyms) $(@:.o=.gendwarfksyms.o) 415else 416cmd_gensymtypes_S = \ 417 $(getasmexports) | \ 418 $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | $(genksyms) 419endif # CONFIG_GENDWARFKSYMS 420 421quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@ 422cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $< 423 424$(obj)/%.s: $(obj)/%.S FORCE 425 $(call if_changed_dep,cpp_s_S) 426 427ifdef CONFIG_ASM_MODVERSIONS 428 429# versioning matches the C process described above, with difference that 430# we parse asm-prototypes.h C header to get function definitions. 431 432cmd_gen_symversions_S = $(call gen_symversions,S) 433 434endif 435 436$(obj)/%.o: $(obj)/%.S FORCE 437 $(call if_changed_rule,as_o_S) 438 439targets += $(filter-out $(subdir-builtin), $(real-obj-y)) 440targets += $(filter-out $(subdir-modorder), $(real-obj-m)) 441targets += $(lib-y) $(always-y) 442 443# Linker scripts preprocessor (.lds.S -> .lds) 444# --------------------------------------------------------------------------- 445quiet_cmd_cpp_lds_S = LDS $@ 446 cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -U$(ARCH) \ 447 -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $< 448 449$(obj)/%.lds: $(src)/%.lds.S FORCE 450 $(call if_changed_dep,cpp_lds_S) 451 452# ASN.1 grammar 453# --------------------------------------------------------------------------- 454quiet_cmd_asn1_compiler = ASN.1 $(basename $@).[ch] 455 cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \ 456 $(basename $@).c $(basename $@).h 457 458$(obj)/%.asn1.c $(obj)/%.asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler 459 $(call cmd,asn1_compiler) 460 461# Build the compiled-in targets 462# --------------------------------------------------------------------------- 463 464# To build objects in subdirs, we need to descend into the directories 465$(subdir-builtin): $(obj)/%/built-in.a: $(obj)/% ; 466$(subdir-modorder): $(obj)/%/modules.order: $(obj)/% ; 467 468# 469# Rule to compile a set of .o files into one .a file (without symbol table) 470# 471# To make this rule robust against "Argument list too long" error, 472# remove $(obj)/ prefix, and restore it by a shell command. 473 474quiet_cmd_ar_builtin = AR $@ 475 cmd_ar_builtin = rm -f $@; \ 476 $(if $(real-prereqs), printf "$(obj)/%s " $(patsubst $(obj)/%,%,$(real-prereqs)) | xargs) \ 477 $(AR) cDPrST $@ 478 479$(obj)/built-in.a: $(real-obj-y) FORCE 480 $(call if_changed,ar_builtin) 481 482# This is a list of build artifacts from the current Makefile and its 483# sub-directories. The timestamp should be updated when any of the member files. 484 485cmd_gen_order = { $(foreach m, $(real-prereqs), \ 486 $(if $(filter %/$(notdir $@), $m), cat $m, echo $m);) :; } \ 487 > $@ 488 489$(obj)/modules.order: $(obj-m) FORCE 490 $(call if_changed,gen_order) 491 492# 493# Rule to compile a set of .o files into one .a file (with symbol table) 494# 495 496$(obj)/lib.a: $(lib-y) FORCE 497 $(call if_changed,ar) 498 499quiet_cmd_ld_multi_m = LD [M] $@ 500 cmd_ld_multi_m = $(LD) $(ld_flags) -r -o $@ @$< $(cmd_objtool) 501 502define rule_ld_multi_m 503 $(call cmd_and_savecmd,ld_multi_m) 504 $(call cmd,gen_objtooldep) 505endef 506 507$(multi-obj-m): private objtool-enabled := $(delay-objtool) 508$(multi-obj-m): private part-of-module := y 509$(multi-obj-m): %.o: %.mod FORCE 510 $(call if_changed_rule,ld_multi_m) 511$(call multi_depend, $(multi-obj-m), .o, -objs -y -m) 512 513# Add intermediate targets: 514# When building objects with specific suffix patterns, add intermediate 515# targets that the final targets are derived from. 516intermediate_targets = $(foreach sfx, $(2), \ 517 $(patsubst %$(strip $(1)),%$(sfx), \ 518 $(filter %$(strip $(1)), $(targets)))) 519# %.asn1.o <- %.asn1.[ch] <- %.asn1 520targets += $(call intermediate_targets, .asn1.o, .asn1.c .asn1.h) 521 522# Include additional build rules when necessary 523# --------------------------------------------------------------------------- 524 525# $(sort ...) is used here to remove duplicated words and excessive spaces. 526hostprogs := $(sort $(hostprogs)) 527ifneq ($(hostprogs),) 528include $(srctree)/scripts/Makefile.host 529endif 530 531# $(sort ...) is used here to remove duplicated words and excessive spaces. 532userprogs := $(sort $(userprogs)) 533ifneq ($(userprogs),) 534include $(srctree)/scripts/Makefile.userprogs 535endif 536 537# Single targets 538# --------------------------------------------------------------------------- 539 540single-subdirs := $(foreach d, $(subdir-ym), $(if $(filter $d/%, $(MAKECMDGOALS)), $d)) 541single-subdir-goals := $(filter $(addsuffix /%, $(single-subdirs)), $(MAKECMDGOALS)) 542 543$(single-subdir-goals): $(single-subdirs) 544 @: 545 546# Descending 547# --------------------------------------------------------------------------- 548 549PHONY += $(subdir-ym) 550$(subdir-ym): 551 $(Q)$(MAKE) $(build)=$@ \ 552 need-builtin=$(if $(filter $@/built-in.a, $(subdir-builtin)),1) \ 553 need-modorder=$(if $(filter $@/modules.order, $(subdir-modorder)),1) \ 554 $(filter $@/%, $(single-subdir-goals)) 555 556# Add FORCE to the prerequisites of a target to force it to be always rebuilt. 557# --------------------------------------------------------------------------- 558 559PHONY += FORCE 560 561FORCE: 562 563targets += $(filter-out $(single-subdir-goals), $(MAKECMDGOALS)) 564targets := $(filter-out $(PHONY), $(targets)) 565 566# Now that targets is fully known, include dtb rules if needed 567ifneq ($(need-dtbslist)$(dtb-y)$(dtb-)$(filter %.dtb %.dtb.o %.dtbo.o,$(targets)),) 568include $(srctree)/scripts/Makefile.dtbs 569endif 570 571# Build 572# Needs to be after the include of Makefile.dtbs, which updates always-y 573# --------------------------------------------------------------------------- 574 575$(obj)/: $(if $(KBUILD_BUILTIN), $(targets-for-builtin)) \ 576 $(if $(KBUILD_MODULES), $(targets-for-modules)) \ 577 $(subdir-ym) $(always-y) 578 @: 579 580# Read all saved command lines and dependencies for the $(targets) we 581# may be building above, using $(if_changed{,_dep}). As an 582# optimization, we don't need to read them if the target does not 583# exist, we will rebuild anyway in that case. 584 585existing-targets := $(wildcard $(sort $(targets))) 586 587-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) 588 589# Create directories for object files if they do not exist 590obj-dirs := $(sort $(patsubst %/,%, $(dir $(targets)))) 591# If targets exist, their directories apparently exist. Skip mkdir. 592existing-dirs := $(sort $(patsubst %/,%, $(dir $(existing-targets)))) 593obj-dirs := $(strip $(filter-out $(existing-dirs), $(obj-dirs))) 594ifneq ($(obj-dirs),) 595$(shell mkdir -p $(obj-dirs)) 596endif 597 598.PHONY: $(PHONY) 599