21.打造专业的编译器环境(中)

21.打造专业的编译器环境(中)

目录

 

1.第二阶段任务

2.关键的实现要点

3.开发中的经验假设

4.解决方案设计

5.makefile中嵌入shell的for循环

6.注意事项

7.工程makefile中的关键构成

8.链接时注意事项

综合

---

1.第二阶段任务

完成编译整个工程的makefile文件

调用模块makefile编译生成静态库文件

链接所有模块的静态文件，最终得到可执行程序

2.关键的实现要点

• 如何自动创建build文件夹以及子文件夹？
• 如何进入每一个模块文件夹进行编译？
• 编译成功后如何链接所有模块静态库？

3.开发中的经验假设

项目中的各个模块字设计阶段就已经基本确定，因此，在之后的开发过程中不会频繁随意的增加或者减少！

 

4.解决方案设计

1.定义变量保存模块名列表(模块名变量)

2.利用shell中的for循环遍历模块名变量

3.在for循环中进入模块文件夹进行编译

4.循环结束后链接所有的模块静态库文件

5.makefile中嵌入shell的for循环

6.注意事项

makefile中嵌入shell代码时，如果需要使用shell变量的值，必须在变量名前加上$$(例:$$dir)!

先写一个shell脚本测试一下

aston@ubuntu:~/disciple$ ./test.sh 
common
module
main
aston@ubuntu:~/disciple$ cat test.sh 
MODULES="common module main"for dir in $MODULES; 
doecho $dir
done

编写makefile

aston@ubuntu:~/disciple$ make test
common
module
main
aston@ubuntu:~/disciple$ cat makefile 
#MODULES := common module main
MODULES := common module main
test :@set -e; for dir in $(MODULES); do echo $$dir; done

7.工程makefile中的关键构成

8.链接时注意事项

• gcc在进行静态链接时必须遵循严格的依赖关系

• 如果不清楚库之间的依赖，可以使用-Xlinker自动确定依赖关系

获取当前工程的绝对路径，同时得到编译存放的相对路径

.PHONY : all compile linkMODULES := common module mainDIR_PROJECT := $(realpath .)
DIR_BUILD := build
DIR_BUILD_SUB := $(addprefix $(DIR_BUILD)/, $(MODULES))all :@echo "$(DIR_PROJECT)"@echo "$(DIR_BUILD_SUB)"test :@set -e; for dir in $(MODULES); do echo $$dir; done

测试一下：

/home/aston/disciple

build/common build/module build/main

 

自动创建对应目录

测试一下

.PHONY : all compile linkMODULES := common module main
MKDIR := mkdir 
RM := rm -rfDIR_PROJECT := $(realpath .)
DIR_BUILD := build
DIR_BUILD_SUB := $(addprefix $(DIR_BUILD)/, $(MODULES))all :@echo "$(DIR_PROJECT)"@echo "$(DIR_BUILD_SUB)"compile : $(DIR_BUILD) $(DIR_BUILD_SUB)@set -e; for dir in $(MODULES); do echo $$dir; done
$(DIR_BUILD) $(DIR_BUILD_SUB) :$(MKDIR) $@
common  main  makefile  module
aston@ubuntu:~/disciple$ make compile
mkdir  build
mkdir  build/common
mkdir  build/module
mkdir  build/main
common
module
main
aston@ubuntu:~/disciple$ ls
build  common  main  makefile  module
aston@ubuntu:~/disciple$ ls build/
common  main  module

现在就可以进去每个模块进行编译

compile : $(DIR_BUILD) $(DIR_BUILD_SUB)@echo "Begin "@set -e; for dir in $(MODULES); do cd $$dir && $(MAKE) all DEBUG:=$(DEBUG) && cd ..; done@echo ""

测试一下:

aston@ubuntu:~/disciple$ make compile
mkdir  build
mkdir  build/common
mkdir  build/module
mkdir  build/main
Begin 
make[1]: Entering directory `/home/aston/disciple/common'
makefile:41: /home/aston/disciple/build/common/common.dep: No such file or directory
makefile:41: /home/aston/disciple/build/common/func.dep: No such file or directory
Creating /home/aston/disciple/build/common/
Creating /home/aston/disciple/build/common/
make[1]: Leaving directory `/home/aston/disciple/common'
make[1]: Entering directory `/home/aston/disciple/common'
ar crs  /home/aston/disciple/build/common.a /home/aston/disciple/build/common/common.o /home/aston/disciple/build/common/func.o
Success! Target ==> /home/aston/disciple/build/common.a
make[1]: Leaving directory `/home/aston/disciple/common'
make[1]: Entering directory `/home/aston/disciple/module'
makefile:41: /home/aston/disciple/build/module/module.dep: No such file or directory
Creating /home/aston/disciple/build/module/
make[1]: Leaving directory `/home/aston/disciple/module'
make[1]: Entering directory `/home/aston/disciple/module'
ar crs  /home/aston/disciple/build/module.a /home/aston/disciple/build/module/module.o
Success! Target ==> /home/aston/disciple/build/module.a
make[1]: Leaving directory `/home/aston/disciple/module'
make[1]: Entering directory `/home/aston/disciple/main'
makefile:41: /home/aston/disciple/build/main/main.dep: No such file or directory
Creating /home/aston/disciple/build/main/
make[1]: Leaving directory `/home/aston/disciple/main'
make[1]: Entering directory `/home/aston/disciple/main'
ar crs  /home/aston/disciple/build/main.a /home/aston/disciple/build/main/main.o
Success! Target ==> /home/aston/disciple/build/main.a
make[1]: Leaving directory `/home/aston/disciple/main'

接下来就是实现link

先将.a文件加上前缀，定义最终生成目标的名和路径

MODULE_LIB := $(addsuffix  .a, $(MODULES))
MODULE_LIB := $(addprefix $(DIR_BUILD)/, $(MODULE_LIB))
APP := app.out
APP := $(addprefix $(DIR_BUILD)/, $(APP))
all :@echo "$(MODULE_LIB)"

测试一下：

make all
build/common.a build/module.a build/main.a
build/app.out
.PHONY : all compile linkMODULES := common module main
MKDIR := mkdir 
RM := rm -rfCC := gcc
LFALGS :=DIR_PROJECT := $(realpath .)
DIR_BUILD := build
DIR_BUILD_SUB := $(addprefix $(DIR_BUILD)/, $(MODULES))
MODULE_LIB := $(addsuffix  .a, $(MODULES))
MODULE_LIB := $(addprefix $(DIR_BUILD)/, $(MODULE_LIB))
APP := app.out
APP := $(addprefix $(DIR_BUILD)/, $(APP))all :@echo "$(MODULE_LIB)"@echo "$(APP)"compile : $(DIR_BUILD) $(DIR_BUILD_SUB)@echo "Begin "@set -e; for dir in $(MODULES); do cd $$dir && $(MAKE) all DEBUG:=$(DEBUG) && cd ..; done@echo ""
link $(APP) : $(MODULE_LIB)@echo "Begin "$(CC) -o $(APP) -Xlinker "-(" $^ -Xlinker "-)" $(LFLAGS)@echo "link success ..."
$(DIR_BUILD) $(DIR_BUILD_SUB) :$(MKDIR) $@

测试一下：

make link
Begin 
gcc -o build/app.out -Xlinker "-(" build/common.a build/module.a build/main.a -Xlinker "-)" 
link success ...
aston@ubuntu:~/disciple$ ./build/app.out 
Version: 1.0.0
main()::start main ...
void common() ...
module_main()::start module ...
void foo()::Hello, D.T.Software ...

优化一下：

.PHONY : all compile link clean rebuild MODULES := common module main
MKDIR := mkdir 
RM := rm -rfCC := gcc
LFALGS :=DIR_PROJECT := $(realpath .)
DIR_BUILD := build
DIR_BUILD_SUB := $(addprefix $(DIR_BUILD)/, $(MODULES))
MODULE_LIB := $(addsuffix  .a, $(MODULES))
MODULE_LIB := $(addprefix $(DIR_BUILD)/, $(MODULE_LIB))
APP := app.out
APP := $(addprefix $(DIR_BUILD)/, $(APP))all : compile $(APP)@echo "Target File ==>$(APP)"compile : $(DIR_BUILD) $(DIR_BUILD_SUB)@echo "Begin "@set -e; for dir in $(MODULES); do cd $$dir && $(MAKE) all DEBUG:=$(DEBUG) && cd ..; done@echo ""
link $(APP) : $(MODULE_LIB)@echo "Begin "$(CC) -o $(APP) -Xlinker "-(" $^ -Xlinker "-)" $(LFLAGS)@echo "link success ..."
$(DIR_BUILD) $(DIR_BUILD_SUB) :$(MKDIR) $@
clean :$(RM) $(DIR_BUILD)
rebuild : clean all@echo ""

• To be continued…

思考：

当前整个项目的makefile是否存在潜在的问题？是否需要重构？

综合

.PHONY : all compile link clean rebuildMODULES := common module mainMKDIR := mkdir
RM := rm -frCC := gcc
LFLAGS := DIR_PROJECT := $(realpath .)
DIR_BUILD := build
DIR_BUILD_SUB := $(addprefix $(DIR_BUILD)/, $(MODULES))
MODULE_LIB := $(addsuffix .a, $(MODULES))
MODULE_LIB := $(addprefix $(DIR_BUILD)/, $(MODULE_LIB))APP := app.out
APP := $(addprefix $(DIR_BUILD)/, $(APP))all : compile $(APP)@echo "Success! Target ==> $(APP)"compile : $(DIR_BUILD) $(DIR_BUILD_SUB)@echo "Begin to compile ..."@set -e; for dir in $(MODULES); do cd $$dir && $(MAKE) all DEBUG:=$(DEBUG) && cd .. ; done@echo "Compile Success!"link $(APP) : $(MODULE_LIB)@echo "Begin to link ..."$(CC) -o $(APP) -Xlinker "-(" $^ -Xlinker "-)" $(LFLAGS)@echo "Link Success!"$(DIR_BUILD) $(DIR_BUILD_SUB) : $(MKDIR) $@clean : @echo "Begin to clean ..."$(RM) $(DIR_BUILD)@echo "Clean Success!"rebuild : clean all