通用Makefile和Makefile.build

通用Makefile

通用的Makefile赠送给大家！

Makefile:
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CROSS_COMPILE = arm-none-linux-gnueabi-

AS			= $(CROSS_COMPILE)as
LD			= $(CROSS_COMPILE)ld
CC			= $(CROSS_COMPILE)gcc
CPP			= $(CC) -E
AR			= $(CROSS_COMPILE)ar
NM			= $(CROSS_COMPILE)nm
STRIP		= $(CROSS_COMPILE)strip
OBJCOPY		= $(CROSS_COMPILE)objcopy
OBJDUMP		= $(CROSS_COMPILE)objdump

# export导出的变量是给子目录下的Makefile使用的
export AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP

# 编译器在编译时的参数设置
CFLAGS := -Wall -O2 -g
# 添加头文件路径，不添加的话include目录下的头文件编译时找不到
CFLAGS += -I $(shell pwd)/include 

# 链接器的链接参数设置
LDFLAGS := 

export CFLAGS LDFLAGS

TOPDIR := $(shell pwd)
export TOPDIR

# 定义将来编译生成的可执行程序的名字
TARGET := imageplayer

# 添加项目中所有用到的源文件，有顶层目录下的.c文件，和子文件夹
# 添加顶层目录下的.c文件
obj-y += main.o
obj-y += a/
obj-y += b/
obj-y += c/

# 添加顶层目录下的子文件夹（注意目录名后面加一个/）


all: 
	make -C ./ -f $(TOPDIR)/Makefile.build
	$(CC) $(LDFLAGS) -o $(TARGET) built-in.o

cp:
	cp ../testproject/ /root/rootfs/ -rf

clean:
	rm -f $(shell find -name "*.o")
	rm -f $(TARGET)

distclean:
	rm -f $(shell find -name "*.o")
	rm -f $(shell find -name "*.d")
	rm -f $(TARGET)
	
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Makefile.build
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PHONY := __build
__build:


obj-y :=
subdir-y :=

include Makefile


__subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y))) #a b c
subdir-y	+= $(__subdir-y) #a b c


subdir_objs := $(foreach f,$(subdir-y),$(f)/built-in.o) #a/built-in.o   b/built-in.o    c/built-in.o


cur_objs := $(filter-out %/, $(obj-y))  #main.o
dep_files := $(foreach f,$(cur_objs),.$(f).d)  #main.o.d
dep_files := $(wildcard $(dep_files))

ifneq ($(dep_files),)
  include $(dep_files)
endif


PHONY += $(subdir-y) # a b c


__build : $(subdir-y) built-in.o

$(subdir-y):
	make -C $@ -f $(TOPDIR)/Makefile.build

built-in.o : $(cur_objs) $(subdir_objs)
	$(LD) -r -o $@ $^

dep_file = .$@.d

%.o : %.c
	$(CC) $(CFLAGS) -Wp,-MD,$(dep_file) -c -o $@ $<
	
.PHONY : $(PHONY)
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