get_depfile_name = $(subst $(comma),_,$($(dir $(1)).$(notdir $(1))).d)
时间: 2023-12-17 12:02:30 浏览: 39
这段代码是定义了一个函数get_depfile_name,它的参数是$(1)。函数首先调用了dir函数获取$(1)中的目录部分,再调用notdir函数获取$(1)中的文件名部分,然后将这两部分以"."连接在一起,作为变量名进行展开,得到一个变量值,再将这个变量值中的逗号($(comma))替换成下划线(_),最后加上后缀".d",作为函数的返回值。因此,如果传入的$(1)是一个文件路径,get_depfile_name函数将返回该文件所在目录和文件名(去掉目录部分后)中间用"."连接的变量名,经过逗号替换后加上".d"后缀的结果。这个函数可能是用来生成一些特殊的依赖文件名。
相关问题
-MD -MP -MF $(depfile) -MT $@ -c -o $@ $< explain this command in detail please
Sure! This is a common command used in Makefiles to generate dependency files during the compilation process in C/C++ programming. Here is an explanation of each parameter:
- `-MD`: This parameter tells the compiler to generate dependency files in the Makefile format. These files are used to track dependencies between source files and header files.
- `-MP`: This parameter generates a phony target for each header file dependency, which ensures that the Makefile won't fail if a header file is deleted or renamed.
- `-MF $(depfile)`: This parameter specifies the name of the dependency file to be generated. The `$(depfile)` variable is typically defined earlier in the Makefile and contains the name and path of the dependency file.
- `-MT $@`: This parameter specifies the name of the target to be built. The `$@` variable represents the name of the target being built, which is typically an object file.
- `-c`: This parameter tells the compiler to generate an object file, but not to link it with other object files to create an executable.
- `-o $@`: This parameter specifies the name of the object file to be generated. The `$@` variable represents the name of the target being built, which is typically an object file.
- `$<`: This is a special variable that represents the name of the first prerequisite (dependency) of the target. In this case, it represents the name of the source file being compiled.
Here is an example command:
```
gcc -MD -MP -MF main.d -MT main.o -c -o main.o main.c
```
This command compiles the source file "main.c" into an object file named "main.o". It also generates a dependency file named "main.d" that tracks the dependencies between "main.c" and any included header files. The `$(depfile)` and `$@` variables are typically defined earlier in the Makefile.
详细介绍一下CMake中add_custom_command函数
A:在CMake中,add_custom_command函数用于添加自定义命令。该函数的语法如下:
```
add_custom_command(TARGET target
POST_BUILD
COMMAND command1 [args1...]
[COMMAND command2 [args2...]...]
[WORKING_DIRECTORY dir]
[COMMENT comment]
[VERBATIM]
[USES_TERMINAL]
[OUTPUT output]
[DEPENDS dep1 [dep2] ... ]
[BYPRODUCTS files... ]
[IMPLICIT_DEPENDS <lang1> <lang2> ... ]
[COMMAND_EXPAND_LISTS]
[SOURCES src1 ...]
[MAIN_DEPENDENCY depfile])
```
其中,TARGET参数表示该自定义命令的目标,可以是一个已经存在的目标,也可以是自定义的名称。POST_BUILD参数表示该命令将在构建目标之后执行。COMMAND参数表示实际要执行的命令及其参数,可以有多个。WORKING_DIRECTORY参数表示要在哪个目录执行该命令。COMMENT参数表示该命令的注释信息。VERBATIM参数表示是否以字面量方式处理命令参数。USES_TERMINAL参数表示是否在终端(terminal)中执行该命令。OUTPUT参数表示该命令创建的输出文件。DEPENDS参数表示该命令依赖的其他文件。BYPRODUCTS参数表示该命令生成的副产品文件。IMPLICIT_DEPENDS参数表示该命令的隐式依赖文件。COMMAND_EXPAND_LISTS参数表示是否要展开命令中的变量或列表。SOURCES参数表示该命令源文件列表。MAIN_DEPENDENCY参数表示该命令主要依赖文件。
通过add_custom_command函数,可以实现各种自定义命令,例如生成代码、打包文件、运行脚本等等。在CMake中,add_custom_command函数对于构建复杂项目非常有用。