tools/scripts/Makefile.include

0001 # SPDX-License-Identifier: GPL-2.0
0002 ifneq ($(O),)
0003 ifeq ($(origin O), command line)
0004         dummy := $(if $(shell cd $(PWD); test -d $(O) || echo $(O)),$(error O=$(O) does not exist),)
0005         ABSOLUTE_O := $(shell cd $(PWD); cd $(O) ; pwd)
0006         OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/)
0007         COMMAND_O := O=$(ABSOLUTE_O)
0008 ifeq ($(objtree),)
0009         objtree := $(O)
0010 endif
0011 endif
0012 endif
0013
0014 # check that the output directory actually exists
0015 ifneq ($(OUTPUT),)
0016 OUTDIR := $(shell cd $(OUTPUT) && pwd)
0017 $(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist))
0018 endif
0019
0020 #
0021 # Include saner warnings here, which can catch bugs:
0022 #
0023 EXTRA_WARNINGS := -Wbad-function-cast
0024 EXTRA_WARNINGS += -Wdeclaration-after-statement
0025 EXTRA_WARNINGS += -Wformat-security
0026 EXTRA_WARNINGS += -Wformat-y2k
0027 EXTRA_WARNINGS += -Winit-self
0028 EXTRA_WARNINGS += -Wmissing-declarations
0029 EXTRA_WARNINGS += -Wmissing-prototypes
0030 EXTRA_WARNINGS += -Wnested-externs
0031 EXTRA_WARNINGS += -Wno-system-headers
0032 EXTRA_WARNINGS += -Wold-style-definition
0033 EXTRA_WARNINGS += -Wpacked
0034 EXTRA_WARNINGS += -Wredundant-decls
0035 EXTRA_WARNINGS += -Wstrict-prototypes
0036 EXTRA_WARNINGS += -Wswitch-default
0037 EXTRA_WARNINGS += -Wswitch-enum
0038 EXTRA_WARNINGS += -Wundef
0039 EXTRA_WARNINGS += -Wwrite-strings
0040 EXTRA_WARNINGS += -Wformat
0041 EXTRA_WARNINGS += -Wno-type-limits
0042
0043 # Makefiles suck: This macro sets a default value of $(2) for the
0044 # variable named by $(1), unless the variable has been set by
0045 # environment or command line. This is necessary for CC and AR
0046 # because make sets default values, so the simpler ?= approach
0047 # won't work as expected.
0048 define allow-override
0049   $(if $(or $(findstring environment,$(origin $(1))),\
0050             $(findstring command line,$(origin $(1)))),,\
0051     $(eval $(1) = $(2)))
0052 endef
0053
0054 ifneq ($(LLVM),)
0055 ifneq ($(filter %/,$(LLVM)),)
0056 LLVM_PREFIX := $(LLVM)
0057 else ifneq ($(filter -%,$(LLVM)),)
0058 LLVM_SUFFIX := $(LLVM)
0059 endif
0060
0061 $(call allow-override,CC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX))
0062 $(call allow-override,AR,$(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX))
0063 $(call allow-override,LD,$(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX))
0064 $(call allow-override,CXX,$(LLVM_PREFIX)clang++$(LLVM_SUFFIX))
0065 $(call allow-override,STRIP,$(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX))
0066 else
0067 # Allow setting various cross-compile vars or setting CROSS_COMPILE as a prefix.
0068 $(call allow-override,CC,$(CROSS_COMPILE)gcc)
0069 $(call allow-override,AR,$(CROSS_COMPILE)ar)
0070 $(call allow-override,LD,$(CROSS_COMPILE)ld)
0071 $(call allow-override,CXX,$(CROSS_COMPILE)g++)
0072 $(call allow-override,STRIP,$(CROSS_COMPILE)strip)
0073 endif
0074
0075 CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?)
0076
0077 ifneq ($(LLVM),)
0078 HOSTAR  ?= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
0079 HOSTCC  ?= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
0080 HOSTLD  ?= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
0081 else
0082 HOSTAR  ?= ar
0083 HOSTCC  ?= gcc
0084 HOSTLD  ?= ld
0085 endif
0086
0087 # Some tools require Clang, LLC and/or LLVM utils
0088 CLANG           ?= clang
0089 LLC             ?= llc
0090 LLVM_CONFIG     ?= llvm-config
0091 LLVM_OBJCOPY    ?= llvm-objcopy
0092 LLVM_STRIP      ?= llvm-strip
0093
0094 ifeq ($(CC_NO_CLANG), 1)
0095 EXTRA_WARNINGS += -Wstrict-aliasing=3
0096
0097 else ifneq ($(CROSS_COMPILE),)
0098 # Allow userspace to override CLANG_CROSS_FLAGS to specify their own
0099 # sysroots and flags or to avoid the GCC call in pure Clang builds.
0100 ifeq ($(CLANG_CROSS_FLAGS),)
0101 CLANG_CROSS_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
0102 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)gcc 2>/dev/null))
0103 ifneq ($(GCC_TOOLCHAIN_DIR),)
0104 CLANG_CROSS_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
0105 CLANG_CROSS_FLAGS += --sysroot=$(shell $(CROSS_COMPILE)gcc -print-sysroot)
0106 CLANG_CROSS_FLAGS += --gcc-toolchain=$(realpath $(GCC_TOOLCHAIN_DIR)/..)
0107 endif # GCC_TOOLCHAIN_DIR
0108 endif # CLANG_CROSS_FLAGS
0109 CFLAGS += $(CLANG_CROSS_FLAGS)
0110 AFLAGS += $(CLANG_CROSS_FLAGS)
0111 endif # CROSS_COMPILE
0112
0113 # Hack to avoid type-punned warnings on old systems such as RHEL5:
0114 # We should be changing CFLAGS and checking gcc version, but this
0115 # will do for now and keep the above -Wstrict-aliasing=3 in place
0116 # in newer systems.
0117 # Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h
0118 #
0119 # See https://lore.kernel.org/lkml/9a8748490611281710g78402fbeh8ff7fcc162dbcbca@mail.gmail.com/
0120 # and https://gcc.gnu.org/gcc-4.8/changes.html,
0121 # that takes into account Linus's comments (search for Wshadow) for the reasoning about
0122 # -Wshadow not being interesting before gcc 4.8.
0123
0124 ifneq ($(filter 3.%,$(MAKE_VERSION)),)  # make-3
0125 EXTRA_WARNINGS += -fno-strict-aliasing
0126 EXTRA_WARNINGS += -Wno-shadow
0127 else
0128 EXTRA_WARNINGS += -Wshadow
0129 endif
0130
0131 ifneq ($(findstring $(MAKEFLAGS), w),w)
0132 PRINT_DIR = --no-print-directory
0133 else
0134 NO_SUBDIR = :
0135 endif
0136
0137 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
0138   silent=1
0139 endif
0140
0141 #
0142 # Define a callable command for descending to a new directory
0143 #
0144 # Call by doing: $(call descend,directory[,target])
0145 #
0146 descend = \
0147         +mkdir -p $(OUTPUT)$(1) && \
0148         $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
0149
0150 QUIET_SUBDIR0  = +$(MAKE) $(COMMAND_O) -C # space to separate -C and subdir
0151 QUIET_SUBDIR1  =
0152
0153 ifneq ($(silent),1)
0154   ifneq ($(V),1)
0155         QUIET_CC       = @echo '  CC      '$@;
0156         QUIET_CC_FPIC  = @echo '  CC FPIC '$@;
0157         QUIET_CLANG    = @echo '  CLANG   '$@;
0158         QUIET_AR       = @echo '  AR      '$@;
0159         QUIET_LINK     = @echo '  LINK    '$@;
0160         QUIET_MKDIR    = @echo '  MKDIR   '$@;
0161         QUIET_GEN      = @echo '  GEN     '$@;
0162         QUIET_SUBDIR0  = +@subdir=
0163         QUIET_SUBDIR1  = ;$(NO_SUBDIR) \
0164                           echo '  SUBDIR  '$$subdir; \
0165                          $(MAKE) $(PRINT_DIR) -C $$subdir
0166         QUIET_FLEX     = @echo '  FLEX    '$@;
0167         QUIET_BISON    = @echo '  BISON   '$@;
0168         QUIET_GENSKEL  = @echo '  GENSKEL '$@;
0169
0170         descend = \
0171                 +@echo         '  DESCEND '$(1); \
0172                 mkdir -p $(OUTPUT)$(1) && \
0173                 $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
0174
0175         QUIET_CLEAN    = @printf '  CLEAN   %s\n' $1;
0176         QUIET_INSTALL  = @printf '  INSTALL %s\n' $1;
0177         QUIET_UNINST   = @printf '  UNINST  %s\n' $1;
0178   endif
0179 endif
0180
0181 pound := \#