在Android编译框架中，把许多固定的、反复用到的目录路径定义为 宏变量，常用 宏 如下：
out/target/product/xxx的宏即为:PRODUCT_OUT
out/target/product/xxx/system的宏即为:TARGET_OUT
out/target/product/xxx/root的宏即为：TARGET_ROOT_OUT，
device/test05/BoardConfig.mk 红色部分即为：TARGET_PRODUCT 宏，一般 TARGET_PRODUCT、 PRODUCT_DEVICE、TARGET_DEVICE，指的是同一个值。
大多数的宏变量 定义位置：build/core/envsetup.mk
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# Variables we check:
# HOST_BUILD_TYPE = { release debug }
# TARGET_BUILD_TYPE = { release debug }
# and we output a bunch of variables, see the case statement at
# the bottom for the full list
# OUT_DIR is also set to "out" if it's not already set.
# this allows you to set it to somewhere else if you like
# Set up version information.
include $(BUILD_SYSTEM)/version_defaults.mk
# ---------------------------------------------------------------
# If you update the build system such that the environment setup
# or buildspec.mk need to be updated, increment this number, and
# people who haven't re-run those will have to do so before they
# can build. Make sure to also update the corresponding value in
# buildspec.mk.default and envsetup.sh.
CORRECT_BUILD_ENV_SEQUENCE_NUMBER := 10
# ---------------------------------------------------------------
# The product defaults to generic on hardware
# NOTE: This will be overridden in product_config.mk if make
# was invoked with a PRODUCT-xxx-yyy goal.
ifeq ($(TARGET_PRODUCT),)
TARGET_PRODUCT := full
endif
# the variant -- the set of files that are included for a build
ifeq ($(strip $(TARGET_BUILD_VARIANT)),)
TARGET_BUILD_VARIANT := eng
endif
# ---------------------------------------------------------------
# Set up configuration for host machine. We don't do cross-
# compiles except for arm, so the HOST is whatever we are
# running on
UNAME := $(shell uname -sm)
# HOST_OS
ifneq (,$(findstring Linux,$(UNAME)))
HOST_OS := linux
endif
ifneq (,$(findstring Darwin,$(UNAME)))
HOST_OS := darwin
endif
ifneq (,$(findstring Macintosh,$(UNAME)))
HOST_OS := darwin
endif
ifneq (,$(findstring CYGWIN,$(UNAME)))
HOST_OS := windows
endif
# BUILD_OS is the real host doing the build.
BUILD_OS := $(HOST_OS)
# Under Linux, if USE_MINGW is set, we change HOST_OS to Windows to build the
# Windows SDK. Only a subset of tools and SDK will manage to build properly.
ifeq ($(HOST_OS),linux)
ifneq ($(USE_MINGW),)
HOST_OS := windows
endif
endif
ifeq ($(HOST_OS),)
$(error Unable to determine HOST_OS from uname -sm: $(UNAME)!)
endif
# HOST_ARCH
ifneq (,$(findstring 86,$(UNAME)))
HOST_ARCH := x86
endif
ifneq (,$(findstring Power,$(UNAME)))
HOST_ARCH := ppc
endif
BUILD_ARCH := $(HOST_ARCH)
ifeq ($(HOST_ARCH),)
$(error Unable to determine HOST_ARCH from uname -sm: $(UNAME)!)
endif
# the host build defaults to release, and it must be release or debug
ifeq ($(HOST_BUILD_TYPE),)
HOST_BUILD_TYPE := release
endif
ifneq ($(HOST_BUILD_TYPE),release)
ifneq ($(HOST_BUILD_TYPE),debug)
$(error HOST_BUILD_TYPE must be either release or debug, not '$(HOST_BUILD_TYPE)')
endif
endif
# This is the standard way to name a directory containing prebuilt host
# objects. E.g., prebuilt/$(HOST_PREBUILT_TAG)/cc
ifeq ($(HOST_OS),windows)
HOST_PREBUILT_TAG := windows
else
HOST_PREBUILT_TAG := $(HOST_OS)-$(HOST_ARCH)
endif
# TARGET_COPY_OUT_* are all relative to the staging directory, ie PRODUCT_OUT.
# Define them here so they can be used in product config files.
TARGET_COPY_OUT_SYSTEM := system
TARGET_COPY_OUT_DATA := data
TARGET_COPY_OUT_VENDOR := system/vendor
TARGET_COPY_OUT_ROOT := root
TARGET_COPY_OUT_RECOVERY := recovery
# Read the product specs so we an get TARGET_DEVICE and other
# variables that we need in order to locate the output files.
include $(BUILD_SYSTEM)/product_config.mk
build_variant := $(filter-out eng user userdebug tests,$(TARGET_BUILD_VARIANT))
ifneq ($(build_variant)-$(words $(TARGET_BUILD_VARIANT)),-1)
$(warning bad TARGET_BUILD_VARIANT: $(TARGET_BUILD_VARIANT))
$(error must be empty or one of: eng user userdebug tests)
endif
# ---------------------------------------------------------------
# Set up configuration for target machine.
# The following must be set:
# TARGET_OS = { linux }
# TARGET_ARCH = { arm | x86 }
ifeq ($(TARGET_ARCH),)
TARGET_ARCH := arm
endif
TARGET_OS := linux
# the target build type defaults to release
ifneq ($(TARGET_BUILD_TYPE),debug)
TARGET_BUILD_TYPE := release
endif
# ---------------------------------------------------------------
# figure out the output directories
ifeq (,$(strip $(OUT_DIR)))
ifeq (,$(strip $(OUT_DIR_COMMON_BASE)))
OUT_DIR := $(TOPDIR)out #指定 OUT_DIR 为 out/
else
OUT_DIR := $(OUT_DIR_COMMON_BASE)/$(notdir $(PWD))
endif
endif
DEBUG_OUT_DIR := $(OUT_DIR)/debug
# Move the host or target under the debug/ directory
# if necessary.
TARGET_OUT_ROOT_release := $(OUT_DIR)/target
TARGET_OUT_ROOT_debug := $(DEBUG_OUT_DIR)/target
TARGET_OUT_ROOT := $(TARGET_OUT_ROOT_$(TARGET_BUILD_TYPE)) #TARGET_BUILD_TYPE这个变量 一般 lunch的时候 指定
HOST_OUT_ROOT_release := $(OUT_DIR)/host
HOST_OUT_ROOT_debug := $(DEBUG_OUT_DIR)/host
HOST_OUT_ROOT := $(HOST_OUT_ROOT_$(HOST_BUILD_TYPE))
HOST_OUT_release := $(HOST_OUT_ROOT_release)/$(HOST_OS)-$(HOST_ARCH)
HOST_OUT_debug := $(HOST_OUT_ROOT_debug)/$(HOST_OS)-$(HOST_ARCH)
HOST_OUT := $(HOST_OUT_$(HOST_BUILD_TYPE))
BUILD_OUT := $(OUT_DIR)/host/$(BUILD_OS)-$(BUILD_ARCH)
TARGET_PRODUCT_OUT_ROOT := $(TARGET_OUT_ROOT)/product
TARGET_COMMON_OUT_ROOT := $(TARGET_OUT_ROOT)/common
HOST_COMMON_OUT_ROOT := $(HOST_OUT_ROOT)/common
PRODUCT_OUT := $(TARGET_PRODUCT_OUT_ROOT)/$(TARGET_DEVICE) #TARGET_DEVICE 在 product_config.mk 里定义，最终 由 PRODUCT_DEVICE决定，而这个 变量是在 具体 lunch 的时候 指定；
OUT_DOCS := $(TARGET_COMMON_OUT_ROOT)/docs
BUILD_OUT_EXECUTABLES:= $(BUILD_OUT)/bin
HOST_OUT_EXECUTABLES:= $(HOST_OUT)/bin
HOST_OUT_SHARED_LIBRARIES:= $(HOST_OUT)/lib
HOST_OUT_JAVA_LIBRARIES:= $(HOST_OUT)/framework
HOST_OUT_SDK_ADDON := $(HOST_OUT)/sdk_addon
HOST_OUT_INTERMEDIATES := $(HOST_OUT)/obj
HOST_OUT_HEADERS:= $(HOST_OUT_INTERMEDIATES)/include
HOST_OUT_INTERMEDIATE_LIBRARIES := $(HOST_OUT_INTERMEDIATES)/lib
HOST_OUT_STATIC_LIBRARIES := $(HOST_OUT_INTERMEDIATE_LIBRARIES)
HOST_OUT_NOTICE_FILES:=$(HOST_OUT_INTERMEDIATES)/NOTICE_FILES
HOST_OUT_COMMON_INTERMEDIATES := $(HOST_COMMON_OUT_ROOT)/obj
TARGET_OUT_INTERMEDIATES := $(PRODUCT_OUT)/obj
TARGET_OUT_HEADERS:= $(TARGET_OUT_INTERMEDIATES)/include
TARGET_OUT_INTERMEDIATE_LIBRARIES := $(TARGET_OUT_INTERMEDIATES)/lib
TARGET_OUT_COMMON_INTERMEDIATES := $(TARGET_COMMON_OUT_ROOT)/obj
TARGET_OUT := $(PRODUCT_OUT)/$(TARGET_COPY_OUT_SYSTEM)
TARGET_OUT_EXECUTABLES:= $(TARGET_OUT)/bin
TARGET_OUT_OPTIONAL_EXECUTABLES:= $(TARGET_OUT)/xbin
TARGET_OUT_SHARED_LIBRARIES:= $(TARGET_OUT)/lib
TARGET_OUT_JAVA_LIBRARIES:= $(TARGET_OUT)/framework
TARGET_OUT_APPS:= $(TARGET_OUT)/app
TARGET_OUT_KEYLAYOUT := $(TARGET_OUT)/usr/keylayout
TARGET_OUT_KEYCHARS := $(TARGET_OUT)/usr/keychars
TARGET_OUT_ETC := $(TARGET_OUT)/etc
TARGET_OUT_STATIC_LIBRARIES:= $(TARGET_OUT_INTERMEDIATES)/lib
TARGET_OUT_NOTICE_FILES:=$(TARGET_OUT_INTERMEDIATES)/NOTICE_FILES
TARGET_OUT_FAKE := $(PRODUCT_OUT)/fake_packages
TARGET_OUT_DATA := $(PRODUCT_OUT)/$(TARGET_COPY_OUT_DATA)
TARGET_OUT_DATA_EXECUTABLES:= $(TARGET_OUT_EXECUTABLES)
TARGET_OUT_DATA_SHARED_LIBRARIES:= $(TARGET_OUT_SHARED_LIBRARIES)
TARGET_OUT_DATA_JAVA_LIBRARIES:= $(TARGET_OUT_JAVA_LIBRARIES)
TARGET_OUT_DATA_APPS:= $(TARGET_OUT_DATA)/app
TARGET_OUT_DATA_KEYLAYOUT := $(TARGET_OUT_KEYLAYOUT)
TARGET_OUT_DATA_KEYCHARS := $(TARGET_OUT_KEYCHARS)
TARGET_OUT_DATA_ETC := $(TARGET_OUT_ETC)
TARGET_OUT_DATA_STATIC_LIBRARIES:= $(TARGET_OUT_STATIC_LIBRARIES)
TARGET_OUT_DATA_NATIVE_TESTS := $(TARGET_OUT_DATA)/nativetest
TARGET_OUT_CACHE := $(PRODUCT_OUT)/cache
TARGET_OUT_VENDOR := $(PRODUCT_OUT)/$(TARGET_COPY_OUT_VENDOR)
TARGET_OUT_VENDOR_EXECUTABLES:= $(TARGET_OUT_VENDOR)/bin
TARGET_OUT_VENDOR_OPTIONAL_EXECUTABLES:= $(TARGET_OUT_VENDOR)/xbin
TARGET_OUT_VENDOR_SHARED_LIBRARIES:= $(TARGET_OUT_VENDOR)/lib
TARGET_OUT_VENDOR_JAVA_LIBRARIES:= $(TARGET_OUT_VENDOR)/framework
TARGET_OUT_VENDOR_APPS:= $(TARGET_OUT_VENDOR)/app
TARGET_OUT_VENDOR_ETC := $(TARGET_OUT_VENDOR)/etc
TARGET_OUT_UNSTRIPPED := $(PRODUCT_OUT)/symbols
TARGET_OUT_EXECUTABLES_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)/system/bin
TARGET_OUT_SHARED_LIBRARIES_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)/system/lib
TARGET_ROOT_OUT_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)
TARGET_ROOT_OUT_SBIN_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)/sbin
TARGET_ROOT_OUT_BIN_UNSTRIPPED := $(TARGET_OUT_UNSTRIPPED)/bin
TARGET_ROOT_OUT := $(PRODUCT_OUT)/$(TARGET_COPY_OUT_ROOT)
TARGET_ROOT_OUT_BIN := $(TARGET_ROOT_OUT)/bin
TARGET_ROOT_OUT_SBIN := $(TARGET_ROOT_OUT)/sbin
TARGET_ROOT_OUT_ETC := $(TARGET_ROOT_OUT)/etc
TARGET_ROOT_OUT_USR := $(TARGET_ROOT_OUT)/usr
TARGET_RECOVERY_OUT := $(PRODUCT_OUT)/$(TARGET_COPY_OUT_RECOVERY)
TARGET_RECOVERY_ROOT_OUT := $(TARGET_RECOVERY_OUT)/root
TARGET_SYSLOADER_OUT := $(PRODUCT_OUT)/sysloader
TARGET_SYSLOADER_ROOT_OUT := $(TARGET_SYSLOADER_OUT)/root
TARGET_SYSLOADER_SYSTEM_OUT := $(TARGET_SYSLOADER_OUT)/root/system
TARGET_INSTALLER_OUT := $(PRODUCT_OUT)/installer
TARGET_INSTALLER_DATA_OUT := $(TARGET_INSTALLER_OUT)/data
TARGET_INSTALLER_ROOT_OUT := $(TARGET_INSTALLER_OUT)/root
TARGET_INSTALLER_SYSTEM_OUT := $(TARGET_INSTALLER_OUT)/root/system
TARGET_FACTORY_RAMDISK_OUT := $(PRODUCT_OUT)/factory_ramdisk
COMMON_MODULE_CLASSES := TARGET-NOTICE_FILES HOST-NOTICE_FILES HOST-JAVA_LIBRARIES
ifeq (,$(strip $(DIST_DIR)))
DIST_DIR := $(OUT_DIR)/dist
endif
ifeq ($(PRINT_BUILD_CONFIG),)
PRINT_BUILD_CONFIG := true
endif
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