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)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),) 64include scripts/Makefile.host 65endif 66 67ifneq ($(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 84obj-y += $(obj)/lib-ksyms.o 85endif 86 87ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),) 88builtin-target := $(obj)/built-in.o 89endif 90 91modorder-target := $(obj)/modules.order 92 93# We keep a list of all modules in $(MODVERDIR) 94 95__build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \ 96 $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \ 97 $(subdir-ym) $(always) 98 @: 99 100# Linus' kernel sanity checking tool 101ifneq ($(KBUILD_CHECKSRC),0) 102 ifeq ($(KBUILD_CHECKSRC),2) 103 quiet_cmd_force_checksrc = CHECK $< 104 cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ; 105 else 106 quiet_cmd_checksrc = CHECK $< 107 cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ; 108 endif 109endif 110 111# Do section mismatch analysis for each module/built-in.o 112ifdef CONFIG_DEBUG_SECTION_MISMATCH 113 cmd_secanalysis = ; scripts/mod/modpost $@ 114endif 115 116# Compile C sources (.c) 117# --------------------------------------------------------------------------- 118 119# Default is built-in, unless we know otherwise 120modkern_cflags = \ 121 $(if $(part-of-module), \ 122 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \ 123 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL)) 124quiet_modtag := $(empty) $(empty) 125 126$(real-objs-m) : part-of-module := y 127$(real-objs-m:.o=.i) : part-of-module := y 128$(real-objs-m:.o=.s) : part-of-module := y 129$(real-objs-m:.o=.lst): part-of-module := y 130 131$(real-objs-m) : quiet_modtag := [M] 132$(real-objs-m:.o=.i) : quiet_modtag := [M] 133$(real-objs-m:.o=.s) : quiet_modtag := [M] 134$(real-objs-m:.o=.lst): quiet_modtag := [M] 135 136$(obj-m) : quiet_modtag := [M] 137 138# Default for not multi-part modules 139modname = $(basetarget) 140 141$(multi-objs-m) : modname = $(modname-multi) 142$(multi-objs-m:.o=.i) : modname = $(modname-multi) 143$(multi-objs-m:.o=.s) : modname = $(modname-multi) 144$(multi-objs-m:.o=.lst) : modname = $(modname-multi) 145$(multi-objs-y) : modname = $(modname-multi) 146$(multi-objs-y:.o=.i) : modname = $(modname-multi) 147$(multi-objs-y:.o=.s) : modname = $(modname-multi) 148$(multi-objs-y:.o=.lst) : modname = $(modname-multi) 149 150quiet_cmd_cc_s_c = CC $(quiet_modtag) $@ 151cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $< 152 153$(obj)/%.s: $(src)/%.c FORCE 154 $(call if_changed_dep,cc_s_c) 155 156quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@ 157cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $< 158 159$(obj)/%.i: $(src)/%.c FORCE 160 $(call if_changed_dep,cpp_i_c) 161 162# These mirror gensymtypes_S and co below, keep them in synch. 163cmd_gensymtypes_c = \ 164 $(CPP) -D__GENKSYMS__ $(c_flags) $< | \ 165 $(GENKSYMS) $(if $(1), -T $(2)) \ 166 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \ 167 $(if $(KBUILD_PRESERVE),-p) \ 168 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null)) 169 170quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@ 171cmd_cc_symtypes_c = \ 172 set -e; \ 173 $(call cmd_gensymtypes_c,true,$@) >/dev/null; \ 174 test -s $@ || rm -f $@ 175 176$(obj)/%.symtypes : $(src)/%.c FORCE 177 $(call cmd,cc_symtypes_c) 178 179# LLVM assembly 180# Generate .ll files from .c 181quiet_cmd_cc_ll_c = CC $(quiet_modtag) $@ 182 cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $< 183 184$(obj)/%.ll: $(src)/%.c FORCE 185 $(call if_changed_dep,cc_ll_c) 186 187# C (.c) files 188# The C file is compiled and updated dependency information is generated. 189# (See cmd_cc_o_c + relevant part of rule_cc_o_c) 190 191quiet_cmd_cc_o_c = CC $(quiet_modtag) $@ 192 193ifndef CONFIG_MODVERSIONS 194cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< 195 196else 197# When module versioning is enabled the following steps are executed: 198# o compile a .tmp_<file>.o from <file>.c 199# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does 200# not export symbols, we just rename .tmp_<file>.o to <file>.o and 201# are done. 202# o otherwise, we calculate symbol versions using the good old 203# genksyms on the preprocessed source and postprocess them in a way 204# that they are usable as a linker script 205# o generate <file>.o from .tmp_<file>.o using the linker to 206# replace the unresolved symbols __crc_exported_symbol with 207# the actual value of the checksum generated by genksyms 208 209cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $< 210 211ifdef CONFIG_LTO_CLANG 212# Generate .o.symversions files for each .o with exported symbols, and link these 213# to the kernel and/or modules at the end. 214cmd_modversions_c = \ 215 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) >/dev/null 2>/dev/null; then \ 216 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \ 217 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ 218 > $(@D)/$(@F).symversions; \ 219 fi; \ 220 else \ 221 if $(LLVM_DIS) -o=- $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \ 222 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ 223 > $(@D)/$(@F).symversions; \ 224 fi; \ 225 fi; \ 226 mv -f $(@D)/.tmp_$(@F) $@; 227else 228cmd_modversions_c = \ 229 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \ 230 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ 231 > $(@D)/.tmp_$(@F:.o=.ver); \ 232 \ 233 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \ 234 -T $(@D)/.tmp_$(@F:.o=.ver); \ 235 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \ 236 else \ 237 mv -f $(@D)/.tmp_$(@F) $@; \ 238 fi; 239endif 240endif 241 242ifdef CONFIG_FTRACE_MCOUNT_RECORD 243ifdef BUILD_C_RECORDMCOUNT 244ifeq ("$(origin RECORDMCOUNT_WARN)", "command line") 245 RECORDMCOUNT_FLAGS = -w 246endif 247 248ifdef CONFIG_LTO_CLANG 249# With LTO, we postpone running recordmcount until after the LTO link step, so 250# let's export the parameters for the link script. 251export RECORDMCOUNT_FLAGS 252else 253# Due to recursion, we must skip empty.o. 254# The empty.o file is created in the make process in order to determine 255# the target endianness and word size. It is made before all other C 256# files, including recordmcount. 257sub_cmd_record_mcount = \ 258 if [ $(@) != "scripts/mod/empty.o" ]; then \ 259 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \ 260 fi; 261endif 262 263recordmcount_source := $(srctree)/scripts/recordmcount.c \ 264 $(srctree)/scripts/recordmcount.h 265else # !BUILD_C_RECORDMCOUNT 266sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \ 267 "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \ 268 "$(if $(CONFIG_64BIT),64,32)" \ 269 "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \ 270 "$(LD)" "$(NM)" "$(RM)" "$(MV)" \ 271 "$(if $(part-of-module),1,0)" "$(@)"; 272 273recordmcount_source := $(srctree)/scripts/recordmcount.pl 274endif # BUILD_C_RECORDMCOUNT 275 276ifndef CONFIG_LTO_CLANG 277cmd_record_mcount = \ 278 if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" = \ 279 "$(CC_FLAGS_FTRACE)" ]; then \ 280 $(sub_cmd_record_mcount) \ 281 fi; 282endif 283endif # CONFIG_FTRACE_MCOUNT_RECORD 284 285ifdef CONFIG_STACK_VALIDATION 286ifneq ($(SKIP_STACK_VALIDATION),1) 287 288__objtool_obj := $(objtree)/tools/objtool/objtool 289 290objtool_args = check 291ifndef CONFIG_FRAME_POINTER 292objtool_args += --no-fp 293endif 294 295# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory 296# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file 297# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file 298cmd_objtool = $(if $(patsubst y%,, \ 299 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \ 300 $(__objtool_obj) $(objtool_args) "$(@)";) 301objtool_obj = $(if $(patsubst y%,, \ 302 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \ 303 $(__objtool_obj)) 304 305endif # SKIP_STACK_VALIDATION 306endif # CONFIG_STACK_VALIDATION 307 308define rule_cc_o_c 309 $(call echo-cmd,checksrc) $(cmd_checksrc) \ 310 $(call cmd_and_fixdep,cc_o_c) \ 311 $(cmd_modversions_c) \ 312 $(cmd_objtool) \ 313 $(call echo-cmd,record_mcount) $(cmd_record_mcount) 314endef 315 316define rule_as_o_S 317 $(call cmd_and_fixdep,as_o_S) \ 318 $(cmd_modversions_S) \ 319 $(cmd_objtool) 320endef 321 322# List module undefined symbols (or empty line if not enabled) 323ifdef CONFIG_TRIM_UNUSED_KSYMS 324cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo 325else 326cmd_undef_syms = echo 327endif 328 329# Built-in and composite module parts 330$(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE 331 $(call cmd,force_checksrc) 332 $(call if_changed_rule,cc_o_c) 333 334# Single-part modules are special since we need to mark them in $(MODVERDIR) 335 336$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE 337 $(call cmd,force_checksrc) 338 $(call if_changed_rule,cc_o_c) 339 @{ echo $(@:.o=.ko); echo $@; \ 340 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod) 341 342quiet_cmd_cc_lst_c = MKLST $@ 343 cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \ 344 $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \ 345 System.map $(OBJDUMP) > $@ 346 347$(obj)/%.lst: $(src)/%.c FORCE 348 $(call if_changed_dep,cc_lst_c) 349 350# Compile assembler sources (.S) 351# --------------------------------------------------------------------------- 352 353modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL) 354 355$(real-objs-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE) 356$(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE) 357 358# .S file exports must have their C prototypes defined in asm/asm-prototypes.h 359# or a file that it includes, in order to get versioned symbols. We build a 360# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from 361# the .S file (with trailing ';'), and run genksyms on that, to extract vers. 362# 363# This is convoluted. The .S file must first be preprocessed to run guards and 364# expand names, then the resulting exports must be constructed into plain 365# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed 366# to make the genksyms input. 367# 368# These mirror gensymtypes_c and co above, keep them in synch. 369cmd_gensymtypes_S = \ 370 (echo "\#include <linux/kernel.h>" ; \ 371 echo "\#include <asm/asm-prototypes.h>" ; \ 372 $(CPP) $(a_flags) $< | \ 373 grep "\<___EXPORT_SYMBOL\>" | \ 374 sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \ 375 $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | \ 376 $(GENKSYMS) $(if $(1), -T $(2)) \ 377 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \ 378 $(if $(KBUILD_PRESERVE),-p) \ 379 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null)) 380 381quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@ 382cmd_cc_symtypes_S = \ 383 set -e; \ 384 $(call cmd_gensymtypes_S,true,$@) >/dev/null; \ 385 test -s $@ || rm -f $@ 386 387$(obj)/%.symtypes : $(src)/%.S FORCE 388 $(call cmd,cc_symtypes_S) 389 390 391quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@ 392cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $< 393 394$(obj)/%.s: $(src)/%.S FORCE 395 $(call if_changed_dep,cpp_s_S) 396 397quiet_cmd_as_o_S = AS $(quiet_modtag) $@ 398 399ifndef CONFIG_MODVERSIONS 400cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< 401 402else 403 404ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h) 405 406ifeq ($(ASM_PROTOTYPES),) 407cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< 408 409else 410 411# versioning matches the C process described above, with difference that 412# we parse asm-prototypes.h C header to get function definitions. 413 414cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $< 415 416cmd_modversions_S = \ 417 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \ 418 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ 419 > $(@D)/.tmp_$(@F:.o=.ver); \ 420 \ 421 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \ 422 -T $(@D)/.tmp_$(@F:.o=.ver); \ 423 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \ 424 else \ 425 mv -f $(@D)/.tmp_$(@F) $@; \ 426 fi; 427endif 428endif 429 430$(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE 431 $(call if_changed_rule,as_o_S) 432 433targets += $(real-objs-y) $(real-objs-m) $(lib-y) 434targets += $(extra-y) $(MAKECMDGOALS) $(always) 435 436# Linker scripts preprocessor (.lds.S -> .lds) 437# --------------------------------------------------------------------------- 438quiet_cmd_cpp_lds_S = LDS $@ 439 cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \ 440 -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $< 441 442$(obj)/%.lds: $(src)/%.lds.S FORCE 443 $(call if_changed_dep,cpp_lds_S) 444 445# ASN.1 grammar 446# --------------------------------------------------------------------------- 447quiet_cmd_asn1_compiler = ASN.1 $@ 448 cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \ 449 $(subst .h,.c,$@) $(subst .c,.h,$@) 450 451.PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h 452 453$(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler 454 $(call cmd,asn1_compiler) 455 456# Build the compiled-in targets 457# --------------------------------------------------------------------------- 458 459# To build objects in subdirs, we need to descend into the directories 460$(sort $(subdir-obj-y)): $(subdir-ym) ; 461 462# 463# Rule to compile a set of .o files into one .o file 464# 465ifdef builtin-target 466 467ifdef CONFIG_LTO_CLANG 468 ifdef CONFIG_MODVERSIONS 469 # combine symversions for later processing 470 update_lto_symversions = \ 471 rm -f $@.symversions; \ 472 for i in $(filter-out FORCE,$^); do \ 473 if [ -f $$i.symversions ]; then \ 474 cat $$i.symversions \ 475 >> $@.symversions; \ 476 fi; \ 477 done; 478 endif 479 # rebuild the symbol table with llvm-ar to include IR files 480 update_lto_symtable = ; \ 481 mv -f $@ $@.tmp; \ 482 $(LLVM_AR) rcsT$(KBUILD_ARFLAGS) $@ \ 483 $$($(AR) t $@.tmp); \ 484 rm -f $@.tmp 485endif 486 487ifdef CONFIG_THIN_ARCHIVES 488 cmd_make_builtin = $(update_lto_symversions) \ 489 rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) 490 cmd_make_empty_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) 491 quiet_cmd_link_o_target = AR $@ 492else 493 cmd_make_builtin = $(LD) $(ld_flags) -r -o 494 cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) 495 quiet_cmd_link_o_target = LD $@ 496endif 497 498# If the list of objects to link is empty, just create an empty built-in.o 499cmd_link_o_target = $(if $(strip $(obj-y)),\ 500 $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \ 501 $(cmd_secanalysis),\ 502 $(cmd_make_empty_builtin) $@) 503 504$(builtin-target): $(obj-y) FORCE 505 $(call if_changed,link_o_target) 506 507targets += $(builtin-target) 508endif # builtin-target 509 510# 511# Rule to create modules.order file 512# 513# Create commands to either record .ko file or cat modules.order from 514# a subdirectory 515modorder-cmds = \ 516 $(foreach m, $(modorder), \ 517 $(if $(filter %/modules.order, $m), \ 518 cat $m;, echo kernel/$m;)) 519 520$(modorder-target): $(subdir-ym) FORCE 521 $(Q)(cat /dev/null; $(modorder-cmds)) > $@ 522 523# 524# Rule to compile a set of .o files into one .a file 525# 526ifdef lib-target 527quiet_cmd_link_l_target = AR $@ 528 529ifdef CONFIG_THIN_ARCHIVES 530 cmd_link_l_target = \ 531 $(update_lto_symversions) \ 532 rm -f $@; \ 533 $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(lib-y) \ 534 $(update_lto_symtable) 535else 536 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y) 537endif 538 539$(lib-target): $(lib-y) FORCE 540 $(call if_changed,link_l_target) 541 542targets += $(lib-target) 543 544dummy-object = $(obj)/.lib_exports.o 545ksyms-lds = $(dot-target).lds 546ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX 547ref_prefix = EXTERN(_ 548else 549ref_prefix = EXTERN( 550endif 551 552filter_export_list = sed -ne '/___ksymtab/s/.*+\([^ "]*\).*/$(ref_prefix)\1)/p' 553link_export_list = rm -f $(dummy-object);\ 554 echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\ 555 $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\ 556 rm $(dummy-object) $(ksyms-lds) 557 558quiet_cmd_export_list = EXPORTS $@ 559 560ifdef CONFIG_LTO_CLANG 561# objdump doesn't understand IR files and llvm-dis doesn't support archives, 562# so we'll walk through each file in the archive separately 563cmd_export_list = \ 564 rm -f $(ksyms-lds); \ 565 for o in $$($(AR) t $<); do \ 566 if $(OBJDUMP) -h $$o >/dev/null 2>/dev/null; then \ 567 $(OBJDUMP) -h $$o | \ 568 $(filter_export_list) \ 569 >>$(ksyms-lds); \ 570 else \ 571 $(LLVM_DIS) -o=- $$o | \ 572 $(filter_export_list) \ 573 >>$(ksyms-lds); \ 574 fi; \ 575 done; \ 576 $(link_export_list) 577else 578cmd_export_list = $(OBJDUMP) -h $< | $(filter_export_list) >$(ksyms-lds); \ 579 $(link_export_list) 580endif 581 582$(obj)/lib-ksyms.o: $(lib-target) FORCE 583 $(call if_changed,export_list) 584 585targets += $(obj)/lib-ksyms.o 586 587endif 588 589# 590# Rule to link composite objects 591# 592# Composite objects are specified in kbuild makefile as follows: 593# <composite-object>-objs := <list of .o files> 594# or 595# <composite-object>-y := <list of .o files> 596# or 597# <composite-object>-m := <list of .o files> 598# The -m syntax only works if <composite object> is a module 599link_multi_deps = \ 600$(filter $(addprefix $(obj)/, \ 601$($(subst $(obj)/,,$(@:.o=-objs))) \ 602$($(subst $(obj)/,,$(@:.o=-y))) \ 603$($(subst $(obj)/,,$(@:.o=-m)))), $^) 604 605cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis) 606 607ifdef CONFIG_THIN_ARCHIVES 608 quiet_cmd_link_multi-y = AR $@ 609 cmd_link_multi-y = $(update_lto_symversions) \ 610 rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) $@ $(link_multi_deps) \ 611 $(update_lto_symtable) 612else 613 quiet_cmd_link_multi-y = LD $@ 614 cmd_link_multi-y = $(cmd_link_multi-link) 615endif 616 617quiet_cmd_link_multi-m = LD [M] $@ 618 619ifdef CONFIG_LTO_CLANG 620 # don't compile IR until needed 621 cmd_link_multi-m = $(cmd_link_multi-y) 622else 623 cmd_link_multi-m = $(cmd_link_multi-link) 624endif 625 626$(multi-used-y): FORCE 627 $(call if_changed,link_multi-y) 628 629$(multi-used-m): FORCE 630 $(call if_changed,link_multi-m) 631 @{ echo $(@:.o=.ko); echo $(link_multi_deps); \ 632 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod) 633 634$(call multi_depend, $(multi-used-y), .o, -objs -y) 635$(call multi_depend, $(multi-used-m), .o, -objs -y -m) 636 637targets += $(multi-used-y) $(multi-used-m) 638 639 640# Descending 641# --------------------------------------------------------------------------- 642 643PHONY += $(subdir-ym) 644$(subdir-ym): 645 $(Q)$(MAKE) $(build)=$@ 646 647# Add FORCE to the prequisites of a target to force it to be always rebuilt. 648# --------------------------------------------------------------------------- 649 650PHONY += FORCE 651 652FORCE: 653 654# Read all saved command lines and dependencies for the $(targets) we 655# may be building above, using $(if_changed{,_dep}). As an 656# optimization, we don't need to read them if the target does not 657# exist, we will rebuild anyway in that case. 658 659targets := $(wildcard $(sort $(targets))) 660cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd)) 661 662ifneq ($(cmd_files),) 663 include $(cmd_files) 664endif 665 666# Declare the contents of the .PHONY variable as phony. We keep that 667# information in a variable se we can use it in if_changed and friends. 668 669.PHONY: $(PHONY) 670