常用的C/C++工程Makefile模板

    在Linux下做开发难免要接触makefile，整个项目的构建都依赖于它。100个developer有100种makefile的写法，在一个较大的项目中，各种各样的makefile无论在开发、后期维护还是整个系统的持续集成都是一个负担。

    有幸参与重构一个遗留系统的makefile，以下是一些心得和一个makefile模板。
    重构目的：
    1.清晰易懂、容易维护
    2.方便系统的持续集成
    重构原则：
    1.子模块makefile模板化
    2.外部依赖、通用宏定义集中化
    3.中间和最终输出集中，便于系统构建

    下面是总结出的一个makefile模板，我在日常的开发中都用它，其中加入了详细的注释。

 

#Get the ROOT_PATH which common files located, assuming this makefile located in $(ROOT_PATH)/src/sub_module ROOT_PATH = $(shell cd ../..; pwd) #Where define the path of third party modules include $(ROOT_PATH)/path #Where define common macros such as CC=gcc, CXX=g++ and so on include $(ROOT_PATH)/common #Set target output path and the path of intermidiate object #The path macros should include in $(ROOT_PATH)/path OUT_PATH = $(OUTPUT_PATH)/submodule OBJ_PATH = $(TMPOBJ_PATH)/submodule TARGET = $(OUT_PATH)/targe #If the targe is share object then set corresponding flags #which should define in $(ROOT_PATH)/common CFLAGS += $(CFLAGS_SO) LDFLAGS += $(LDFLAGS_SO) #Custom Predefines CFLAGS += -DXXXXXXXX CFLAGS += -DYYYYYYYY #Dependent header files #The path macros should include in $(ROOT_PATH)/path CFLAGS += -I. / -I$(XXXX_INC) / -I$(YYYY_INC) / -I$(ZZZZ_INC) #Dependent libraries #The path macros should include in $(ROOT_PATH)/path LDFLAGS += -L$(XXXX_LIB) -lxxxx / -L$(YYYY_LIB) -lyyyy #Set CPP source directory CPP_SRCDIR = . #Or set specific CPP Source files ADDITIONAL_CPP_SOURCES = / $(PATH_A)/a.cpp / $(PATH_B)/b.cpp #Traverse every directory in $(CPP_SRCDIR), and find every cpp file CPP_SOURCES = $(foreach d,$(CPP_SRCDIR),$(wildcard $(d)/*.cpp) ) $(ADDITIONAL_CPP_SOURCES) #Traverse every cpp file in $(CPP_SOURCES) and get corresponding object file(.o) CPP_OBJFILES = $(patsubst %.cpp,$(OBJ_PATH)/%.o,$(notdir $(CPP_SOURCES))) #Set C source directory C_SRCDIR = #Or set specific C Source files ADDITIONAL_C_SOURCES = / $(PATH_A)/a.c / $(PATH_B)/b.c #C Source files C_SOURCES = $(foreach d,$(C_SRCDIR),$(wildcard $(d)/*.c) ) $(ADDITIONAL_C_SOURCES) C_OBJFILES = $(patsubst %.c,$(OBJ_PATH)/%.o,$(notdir $(C_SOURCES))) #Set vpath where to find these types of files vpath %.cpp $(dir $(CPP_SOURCES)) vpath %.c $(dir $(C_SOURCES)) vpath %.o $(OBJ_PATH) #The first target to be executed all: target target: $(TARGET) #Static dependecy pattern #$(OBJ_PATH)/%.o define the pattern of target and %.c or %.cpp is the final dependency $(C_OBJFILES): $(OBJ_PATH)/%.o: %.c -mkdir -p $(OBJ_PATH) $(CXX) -c $(CFLAGS) -o $@ $< $(CPP_OBJFILES): $(OBJ_PATH)/%.o: %.cpp -mkdir -p $(OBJ_PATH) $(CXX) -c $(CFLAGS) -o $@ $< $(TARGET): $(CPP_OBJFILES) $(C_OBJFILES) -mkdir -p $(OUT_PATH) $(CXX) -o $@ $^ $(LDFLAGS) clean: -rm -rf $(OBJ_PATH) -rm -f $(TARGET)