我把主Makefile拷贝下来，仔细看看，然后解析，记录下来
1. 文件
TOPDIR:=${CURDIR} //定义变量
LC_ALL:=C //定义变量
LANG:=C //定义变量
export TOPDIR LC_ALL LANG // 导出变量
empty:= //定义变量
space:= $(empty) $(empty) //定义变量
#判断路径是否有空格
$(if $(findstring $(space),$(TOPDIR)),$(error ERROR: The path to the OpenWrt directory must not include any spaces))world: //目标
include $(TOPDIR)/include/host.mk // 包含host.mk 文件
ifneq ($(OPENWRT_BUILD),1)
_SINGLE=export MAKEFLAGS=$(space);
override OPENWRT_BUILD=1
export OPENWRT_BUILD
GREP_OPTIONS=
export GREP_OPTIONS
include $(TOPDIR)/include/debug.mk
include $(TOPDIR)/include/depends.mk
include $(TOPDIR)/include/toplevel.mk
else
include rules.mk
include $(INCLUDE_DIR)/depends.mk
include $(INCLUDE_DIR)/subdir.mk
include target/Makefile
include package/Makefile
include tools/Makefile
include toolchain/Makefile
$(toolchain/stamp-install): $(tools/stamp-install)
$(target/stamp-compile): $(toolchain/stamp-install) $(tools/stamp-install) $(BUILD_DIR)/.prepared
$(package/stamp-compile): $(target/stamp-compile) $(package/stamp-cleanup)
$(package/stamp-install): $(package/stamp-compile)
$(target/stamp-install): $(package/stamp-compile) $(package/stamp-install)
printdb:
@true //make 动作不显示
prepare: $(target/stamp-compile)
#//删除文件
clean: FORCE
rm -rf $(BUILD_DIR) $(STAGING_DIR) $(BIN_DIR) $(BUILD_LOG_DIR)
#//删除文件
dirclean: clean
rm -rf $(STAGING_DIR_HOST) $(TOOLCHAIN_DIR) $(BUILD_DIR_HOST) $(BUILD_DIR_TOOLCHAIN)
rm -rf $(TMP_DIR)
ifndef DUMP_TARGET_DB
$(BUILD_DIR)/.prepared: Makefile
@mkdir -p $$(dirname $@)
@touch $@
tmp/.prereq_packages: .config
unset ERROR; \
for package in $(sort $(prereq-y) $(prereq-m)); do \
$(_SINGLE)$(NO_TRACE_MAKE) -s -r -C package/$$package prereq || ERROR=1; \
done; \
if [ -n "$$ERROR" ]; then \
echo "Package prerequisite check failed."; \
false; \
fi
touch $@
endif
# check prerequisites before starting to build //注释
prereq: $(target/stamp-prereq) tmp/.prereq_packages
@if [ ! -f "$(INCLUDE_DIR)/site/$(ARCH)" ]; then \
echo 'ERROR: Missing site config for architecture "$(ARCH)" !'; \
echo ' The missing file will cause configure scripts to fail during compilation.'; \
echo ' Please provide a "$(INCLUDE_DIR)/site/$(ARCH)" file and restart the build.'; \
exit 1; \
fi
prepare: .config $(tools/stamp-install) $(toolchain/stamp-install)
world: prepare $(target/stamp-compile) $(package/stamp-compile) $(package/stamp-install) $(target/stamp-install) FORCE
$(_SINGLE)$(SUBMAKE) -r package/index
.PHONY: clean dirclean prereq prepare world package/symlinks package/symlinks-install package/symlinks-clean
endif