name : Makefile.include # SPDX-License-Identifier: GPL-2.0 ifneq ($(O),) ifeq ($(origin O), command line) dummy := $(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) endif $(call allow-override,CC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX)) $(call allow-override,AR,$(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)) $(call allow-override,LD,$(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)) 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) endif CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?) ifneq ($(LLVM),) HOSTAR ?= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX) HOSTCC ?= $(LLVM_PREFIX)clang$(LLVM_SUFFIX) HOSTLD ?= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX) else HOSTAR ?= ar HOSTCC ?= gcc HOSTLD ?= ld endif # Some tools require Clang, LLC and/or LLVM utils CLANG ?= clang LLC ?= llc LLVM_CONFIG ?= llvm-config LLVM_OBJCOPY ?= llvm-objcopy LLVM_STRIP ?= llvm-strip 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_CROSS_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%)) 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 # 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 endif # # 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 := \#