# SPDX-License-Identifier: GPL-2.0ifneq ($(O),)ifeq ($(origin O), command line) $(if $(shell cd $(PWD); test -d $(O) || echo $(O)),$(error O=$(O) does not exist),) ABSOLUTE_O := $(shell cd $(PWD); cd $(O) ; pwd) OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/) COMMAND_O := O=$(ABSOLUTE_O)ifeq ($(objtree),) objtree := $(O)endifendifendif # check that the output directory actually existsifneq ($(OUTPUT),)OUTDIR := $(shell cd $(OUTPUT) && pwd)$(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist))endif ## Include saner warnings here, which can catch bugs:#EXTRA_WARNINGS := -Wbad-function-castEXTRA_WARNINGS += -Wdeclaration-after-statementEXTRA_WARNINGS += -Wformat-securityEXTRA_WARNINGS += -Wformat-y2kEXTRA_WARNINGS += -Winit-selfEXTRA_WARNINGS += -Wmissing-declarationsEXTRA_WARNINGS += -Wmissing-prototypesEXTRA_WARNINGS += -Wnested-externsEXTRA_WARNINGS += -Wno-system-headersEXTRA_WARNINGS += -Wold-style-definitionEXTRA_WARNINGS += -WpackedEXTRA_WARNINGS += -Wredundant-declsEXTRA_WARNINGS += -Wstrict-prototypesEXTRA_WARNINGS += -Wswitch-defaultEXTRA_WARNINGS += -Wswitch-enumEXTRA_WARNINGS += -WundefEXTRA_WARNINGS += -Wwrite-stringsEXTRA_WARNINGS += -WformatEXTRA_WARNINGS += -Wno-type-limits # Makefiles suck: This macro sets a default value of $(2) for the# variable named by $(1), unless the variable has been set by# environment or command line. This is necessary for CC and AR# because make sets default values, so the simpler ?= approach# won't work as expected.define allow-override $(if $(or $(findstring environment,$(origin $(1))),\ $(findstring command line,$(origin $(1)))),,\ $(eval $(1) = $(2)))endef ifneq ($(LLVM),) ifneq ($(filter %/,$(LLVM)),) LLVM_PREFIX := $(LLVM) else ifneq ($(filter -%,$(LLVM)),) LLVM_SUFFIX := $(LLVM) else ifneq ($(LLVM),1) $(error Invalid value for LLVM, see Documentation/kbuild/llvm.rst) endif $(call allow-override,CC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX)) $(call allow-override,CLANG,$(LLVM_PREFIX)clang$(LLVM_SUFFIX)) $(call allow-override,HOSTCC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX)) $(call allow-override,AR,$(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)) $(call allow-override,HOSTAR,$(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)) $(call allow-override,LD,$(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)) $(call allow-override,HOSTLD,$(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)) $(call allow-override,CXX,$(LLVM_PREFIX)clang++$(LLVM_SUFFIX)) $(call allow-override,STRIP,$(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)) $(call allow-override,LLVM_STRIP,$(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)) $(call allow-override,LLC,$(LLVM_PREFIX)llc$(LLVM_SUFFIX)) $(call allow-override,LLVM_CONFIG,$(LLVM_PREFIX)llvm-config$(LLVM_SUFFIX)) $(call allow-override,LLVM_OBJCOPY,$(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)) $(call allow-override,READELF,$(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)) $(call allow-override,HOSTREADELF,$(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX))else # Allow setting various cross-compile vars or setting CROSS_COMPILE as a prefix. $(call allow-override,CC,$(CROSS_COMPILE)gcc) $(call allow-override,AR,$(CROSS_COMPILE)ar) $(call allow-override,LD,$(CROSS_COMPILE)ld) $(call allow-override,CXX,$(CROSS_COMPILE)g++) $(call allow-override,STRIP,$(CROSS_COMPILE)strip) $(call allow-override,READELF,$(CROSS_COMPILE)readelf) # Host versions aren't prefixed $(call allow-override,HOSTAR,ar) $(call allow-override,HOSTCC,gcc) $(call allow-override,HOSTLD,ld) $(call allow-override,HOSTREADELF,readelf) # Some tools still require Clang, LLC and/or LLVM utils $(call allow-override,CLANG,clang) $(call allow-override,LLC,llc) $(call allow-override,LLVM_CONFIG,llvm-config) $(call allow-override,LLVM_OBJCOPY,llvm-objcopy) $(call allow-override,LLVM_STRIP,llvm-strip)endif # The CC_NO_CLANG probe also runs at parse time for targets that never# compile, so guard it with 'command -v': when the compiler is not yet# installed, e.g. the first install-build-deps run, it would otherwise# spew "gcc: not found". Only the first word of CC is consulted, as CC# may carry arguments, e.g. 'ccache gcc'. A missing compiler leaves# CC_NO_CLANG at 1, as if the probe had failed.CC_NO_CLANG := $(shell if command -v $(firstword $(CC)) >/dev/null 2>&1; then $(CC) -dM -E -x c /dev/null; fi | grep -Fq "__clang__"; echo $$?) # Some tools require bpftoolSYSTEM_BPFTOOL ?= bpftool RUSTC ?= rustc ifeq ($(CC_NO_CLANG), 1)EXTRA_WARNINGS += -Wstrict-aliasing=3 else ifneq ($(CROSS_COMPILE),)# Allow userspace to override CLANG_CROSS_FLAGS to specify their own# sysroots and flags or to avoid the GCC call in pure Clang builds.ifeq ($(CLANG_CROSS_FLAGS),)CLANG_TARGET := $(notdir $(CROSS_COMPILE:%-=%))CLANG_TARGET := $(subst s390-linux,s390x-linux,$(CLANG_TARGET))CLANG_CROSS_FLAGS := --target=$(CLANG_TARGET)GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)gcc 2>/dev/null))ifneq ($(GCC_TOOLCHAIN_DIR),)CLANG_CROSS_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))CLANG_CROSS_FLAGS += --sysroot=$(shell $(CROSS_COMPILE)gcc -print-sysroot)CLANG_CROSS_FLAGS += --gcc-toolchain=$(realpath $(GCC_TOOLCHAIN_DIR)/..)endif # GCC_TOOLCHAIN_DIRendif # CLANG_CROSS_FLAGSCFLAGS += $(CLANG_CROSS_FLAGS)AFLAGS += $(CLANG_CROSS_FLAGS)elseCLANG_CROSS_FLAGS :=endif # CROSS_COMPILE # Hack to avoid type-punned warnings on old systems such as RHEL5:# We should be changing CFLAGS and checking gcc version, but this# will do for now and keep the above -Wstrict-aliasing=3 in place# in newer systems.# Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h## See https://lore.kernel.org/lkml/9a8748490611281710g78402fbeh8ff7fcc162dbcbca@mail.gmail.com/# and https://gcc.gnu.org/gcc-4.8/changes.html,# that takes into account Linus's comments (search for Wshadow) for the reasoning about# -Wshadow not being interesting before gcc 4.8. ifneq ($(filter 3.%,$(MAKE_VERSION)),) # make-3EXTRA_WARNINGS += -fno-strict-aliasingEXTRA_WARNINGS += -Wno-shadowelseEXTRA_WARNINGS += -Wshadowendif ifneq ($(findstring $(MAKEFLAGS), w),w)PRINT_DIR = --no-print-directoryelseNO_SUBDIR = :endif # Beautify output# ---------------------------------------------------------------------------## Most of build commands in Kbuild start with "cmd_". You can optionally define# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from# that command is printed by default.## e.g.)# quiet_cmd_depmod = DEPMOD $(MODLIB)# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)## A simple variant is to prefix commands with $(Q) - that's useful# for commands that shall be hidden in non-verbose mode.## $(Q)$(MAKE) $(build)=scripts/basic## To put more focus on warnings, be less verbose as default# Use 'make V=1' to see the full commands ifeq ($(V),1) quiet = Q =else quiet = quiet_ Q = @endif # If the user is running make -s (silent mode), suppress echoing of commands# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.ifeq ($(filter 3.%,$(MAKE_VERSION)),)short-opts := $(firstword -$(MAKEFLAGS))elseshort-opts := $(filter-out --%,$(MAKEFLAGS))endif ifneq ($(findstring s,$(short-opts)),) silent=1 quiet=silent_endif export quiet Q ## Define a callable command for descending to a new directory## Call by doing: $(call descend,directory[,target])#descend = \ +mkdir -p $(OUTPUT)$(1) && \ $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2) QUIET_SUBDIR0 = +$(MAKE) $(COMMAND_O) -C # space to separate -C and subdirQUIET_SUBDIR1 = ifneq ($(silent),1) ifneq ($(V),1) QUIET_CC = @echo ' CC '$@; QUIET_CC_FPIC = @echo ' CC FPIC '$@; QUIET_CLANG = @echo ' CLANG '$@; QUIET_AR = @echo ' AR '$@; QUIET_LINK = @echo ' LINK '$@; QUIET_MKDIR = @echo ' MKDIR '$@; QUIET_GEN = @echo ' GEN '$@; QUIET_SUBDIR0 = +@subdir= QUIET_SUBDIR1 = ;$(NO_SUBDIR) \ echo ' SUBDIR '$$subdir; \ $(MAKE) $(PRINT_DIR) -C $$subdir QUIET_FLEX = @echo ' FLEX '$@; QUIET_BISON = @echo ' BISON '$@; QUIET_GENSKEL = @echo ' GENSKEL '$@; descend = \ +@echo ' DESCEND '$(1); \ mkdir -p $(OUTPUT)$(1) && \ $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2) QUIET_CLEAN = @printf ' CLEAN %s\n' $1; QUIET_INSTALL = @printf ' INSTALL %s\n' $1; QUIET_UNINST = @printf ' UNINST %s\n' $1; endifendif pound := \#
# SPDX-License-Identifier: GPL-2.0
ifneq ($(O),)
ifeq ($(origin O), command line)
$(if $(shell cd $(PWD); test -d $(O) || echo $(O)),$(error O=$(O) does not exist),)
ABSOLUTE_O := $(shell cd $(PWD); cd $(O) ; pwd)
OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/)
COMMAND_O := O=$(ABSOLUTE_O)
ifeq ($(objtree),)
objtree := $(O)
endif
endif
endif
# check that the output directory actually exists
ifneq ($(OUTPUT),)
OUTDIR := $(shell cd $(OUTPUT) && pwd)
$(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist))
endif
#
# Include saner warnings here, which can catch bugs:
#
EXTRA_WARNINGS := -Wbad-function-cast
EXTRA_WARNINGS += -Wdeclaration-after-statement
EXTRA_WARNINGS += -Wformat-security
EXTRA_WARNINGS += -Wformat-y2k
EXTRA_WARNINGS += -Winit-self
EXTRA_WARNINGS += -Wmissing-declarations
EXTRA_WARNINGS += -Wmissing-prototypes
EXTRA_WARNINGS += -Wnested-externs
EXTRA_WARNINGS += -Wno-system-headers
EXTRA_WARNINGS += -Wold-style-definition
EXTRA_WARNINGS += -Wpacked
EXTRA_WARNINGS += -Wredundant-decls
EXTRA_WARNINGS += -Wstrict-prototypes
EXTRA_WARNINGS += -Wswitch-default
EXTRA_WARNINGS += -Wswitch-enum
EXTRA_WARNINGS += -Wundef
EXTRA_WARNINGS += -Wwrite-strings
EXTRA_WARNINGS += -Wformat
EXTRA_WARNINGS += -Wno-type-limits
# Makefiles suck: This macro sets a default value of $(2) for the
# variable named by $(1), unless the variable has been set by
# environment or command line. This is necessary for CC and AR
# because make sets default values, so the simpler ?= approach
# won't work as expected.
define allow-override
$(if $(or $(findstring environment,$(origin $(1))),\
$(findstring command line,$(origin $(1)))),,\
$(eval $(1) = $(2)))
endef
ifneq ($(LLVM),)
ifneq ($(filter %/,$(LLVM)),)
LLVM_PREFIX := $(LLVM)
else ifneq ($(filter -%,$(LLVM)),)
LLVM_SUFFIX := $(LLVM)
else ifneq ($(LLVM),1)
$(error Invalid value for LLVM, see Documentation/kbuild/llvm.rst)
endif
$(call allow-override,CC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX))
$(call allow-override,CLANG,$(LLVM_PREFIX)clang$(LLVM_SUFFIX))
$(call allow-override,HOSTCC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX))
$(call allow-override,AR,$(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX))
$(call allow-override,HOSTAR,$(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX))
$(call allow-override,LD,$(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX))
$(call allow-override,HOSTLD,$(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX))
$(call allow-override,CXX,$(LLVM_PREFIX)clang++$(LLVM_SUFFIX))
$(call allow-override,STRIP,$(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX))
$(call allow-override,LLVM_STRIP,$(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX))
$(call allow-override,LLC,$(LLVM_PREFIX)llc$(LLVM_SUFFIX))
$(call allow-override,LLVM_CONFIG,$(LLVM_PREFIX)llvm-config$(LLVM_SUFFIX))
$(call allow-override,LLVM_OBJCOPY,$(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX))
$(call allow-override,READELF,$(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX))
$(call allow-override,HOSTREADELF,$(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX))
else
# Allow setting various cross-compile vars or setting CROSS_COMPILE as a prefix.
$(call allow-override,CC,$(CROSS_COMPILE)gcc)
$(call allow-override,AR,$(CROSS_COMPILE)ar)
$(call allow-override,LD,$(CROSS_COMPILE)ld)
$(call allow-override,CXX,$(CROSS_COMPILE)g++)
$(call allow-override,STRIP,$(CROSS_COMPILE)strip)
$(call allow-override,READELF,$(CROSS_COMPILE)readelf)
# Host versions aren't prefixed
$(call allow-override,HOSTAR,ar)
$(call allow-override,HOSTCC,gcc)
$(call allow-override,HOSTLD,ld)
$(call allow-override,HOSTREADELF,readelf)
# Some tools still require Clang, LLC and/or LLVM utils
$(call allow-override,CLANG,clang)
$(call allow-override,LLC,llc)
$(call allow-override,LLVM_CONFIG,llvm-config)
$(call allow-override,LLVM_OBJCOPY,llvm-objcopy)
$(call allow-override,LLVM_STRIP,llvm-strip)
endif
# The CC_NO_CLANG probe also runs at parse time for targets that never
# compile, so guard it with 'command -v': when the compiler is not yet
# installed, e.g. the first install-build-deps run, it would otherwise
# spew "gcc: not found". Only the first word of CC is consulted, as CC
# may carry arguments, e.g. 'ccache gcc'. A missing compiler leaves
# CC_NO_CLANG at 1, as if the probe had failed.
CC_NO_CLANG := $(shell if command -v $(firstword $(CC)) >/dev/null 2>&1; then $(CC) -dM -E -x c /dev/null; fi | grep -Fq "__clang__"; echo $$?)
# Some tools require bpftool
SYSTEM_BPFTOOL ?= bpftool
RUSTC ?= rustc
ifeq ($(CC_NO_CLANG), 1)
EXTRA_WARNINGS += -Wstrict-aliasing=3
else ifneq ($(CROSS_COMPILE),)
# Allow userspace to override CLANG_CROSS_FLAGS to specify their own
# sysroots and flags or to avoid the GCC call in pure Clang builds.
ifeq ($(CLANG_CROSS_FLAGS),)
CLANG_TARGET := $(notdir $(CROSS_COMPILE:%-=%))
CLANG_TARGET := $(subst s390-linux,s390x-linux,$(CLANG_TARGET))
CLANG_CROSS_FLAGS := --target=$(CLANG_TARGET)
GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)gcc 2>/dev/null))
ifneq ($(GCC_TOOLCHAIN_DIR),)
CLANG_CROSS_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
CLANG_CROSS_FLAGS += --sysroot=$(shell $(CROSS_COMPILE)gcc -print-sysroot)
CLANG_CROSS_FLAGS += --gcc-toolchain=$(realpath $(GCC_TOOLCHAIN_DIR)/..)
endif # GCC_TOOLCHAIN_DIR
endif # CLANG_CROSS_FLAGS
CFLAGS += $(CLANG_CROSS_FLAGS)
AFLAGS += $(CLANG_CROSS_FLAGS)
else
CLANG_CROSS_FLAGS :=
endif # CROSS_COMPILE
# Hack to avoid type-punned warnings on old systems such as RHEL5:
# We should be changing CFLAGS and checking gcc version, but this
# will do for now and keep the above -Wstrict-aliasing=3 in place
# in newer systems.
# Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h
#
# See https://lore.kernel.org/lkml/9a8748490611281710g78402fbeh8ff7fcc162dbcbca@mail.gmail.com/
# and https://gcc.gnu.org/gcc-4.8/changes.html,
# that takes into account Linus's comments (search for Wshadow) for the reasoning about
# -Wshadow not being interesting before gcc 4.8.
ifneq ($(filter 3.%,$(MAKE_VERSION)),) # make-3
EXTRA_WARNINGS += -fno-strict-aliasing
EXTRA_WARNINGS += -Wno-shadow
else
EXTRA_WARNINGS += -Wshadow
endif
ifneq ($(findstring $(MAKEFLAGS), w),w)
PRINT_DIR = --no-print-directory
else
NO_SUBDIR = :
endif
# Beautify output
# ---------------------------------------------------------------------------
#
# Most of build commands in Kbuild start with "cmd_". You can optionally define
# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
# that command is printed by default.
#
# e.g.)
# quiet_cmd_depmod = DEPMOD $(MODLIB)
# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
#
# A simple variant is to prefix commands with $(Q) - that's useful
# for commands that shall be hidden in non-verbose mode.
#
# $(Q)$(MAKE) $(build)=scripts/basic
#
# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands
ifeq ($(V),1)
quiet =
Q =
else
quiet = quiet_
Q = @
endif
# If the user is running make -s (silent mode), suppress echoing of commands
# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
ifeq ($(filter 3.%,$(MAKE_VERSION)),)
short-opts := $(firstword -$(MAKEFLAGS))
else
short-opts := $(filter-out --%,$(MAKEFLAGS))
endif
ifneq ($(findstring s,$(short-opts)),)
silent=1
quiet=silent_
endif
export quiet Q
#
# Define a callable command for descending to a new directory
#
# Call by doing: $(call descend,directory[,target])
#
descend = \
+mkdir -p $(OUTPUT)$(1) && \
$(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
QUIET_SUBDIR0 = +$(MAKE) $(COMMAND_O) -C # space to separate -C and subdir
QUIET_SUBDIR1 =
ifneq ($(silent),1)
ifneq ($(V),1)
QUIET_CC = @echo ' CC '$@;
QUIET_CC_FPIC = @echo ' CC FPIC '$@;
QUIET_CLANG = @echo ' CLANG '$@;
QUIET_AR = @echo ' AR '$@;
QUIET_LINK = @echo ' LINK '$@;
QUIET_MKDIR = @echo ' MKDIR '$@;
QUIET_GEN = @echo ' GEN '$@;
QUIET_SUBDIR0 = +@subdir=
QUIET_SUBDIR1 = ;$(NO_SUBDIR) \
echo ' SUBDIR '$$subdir; \
$(MAKE) $(PRINT_DIR) -C $$subdir
QUIET_FLEX = @echo ' FLEX '$@;
QUIET_BISON = @echo ' BISON '$@;
QUIET_GENSKEL = @echo ' GENSKEL '$@;
descend = \
+@echo ' DESCEND '$(1); \
mkdir -p $(OUTPUT)$(1) && \
$(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
QUIET_CLEAN = @printf ' CLEAN %s\n' $1;
QUIET_INSTALL = @printf ' INSTALL %s\n' $1;
QUIET_UNINST = @printf ' UNINST %s\n' $1;
endif
endif
pound := \#