问题

如下图文件夹

> include: *.h文件
> out: 编译后的输出文件夹
> source：*.cpp文件

先看看我们的几个文件夹里有什么文件，还有文件里有什么内容。

include

• add.h
  • 这里就是add()函数的声明
  • 还需要要加上 int test_add();这个声明
    

source

• main.cpp
  • 简单的一个程序入口
    
• add.cpp
  • 这里是我们主要的程序部分，定义了几个add()函数。还有test_add()函数
  • 还需要#include “add.h”
    

out

• 现在还没有编译过，所以为空

那我们要怎样配置vscode里的一些环境呢？

配置过程遇到的问题与解决

遇到的问题1

identifier "test_add" is undefinedC/C++(20)

说白了，就是test_add这个标识符不能识别（没有定义），可我们从上面的文件里看到了，该函数都是有的。再往下看，我们一个一个来解决。

解决步骤

1. ctrl + shift + p

然后选择如下箭头所指示

出现如下，选择Debug Anyway

完成这一步了，我们可以参文件下面，会有一个.vscode的文件夹，还有两个.json的文件。

2. 配置json文件

修改task.json文件

默认的如下，主要要修改三个地方

1. 添加 -I，及-I对应的文件夹 (include)
2. 修改 -o，及-o对文件夹 (out)
3. 修改-g，及-g对应的文件(source)

{"tasks": [{"type": "cppbuild","label": "C/C++: g++ build active file","command": "/usr/bin/g++","args": ["-g","${file}","-o","${fileDirname}/${fileBasenameNoExtension}"],"options": {"cwd": "${fileDirname}"},"problemMatcher": ["$gcc"],"group": {"kind": "build","isDefault": true},"detail": "Task generated by Debugger."}],"version": "2.0.0"
}

修改如下

{"tasks": [{"type": "cppbuild","label": "C/C++: g++ build active file","command": "/usr/bin/g++","args": ["-g","${workspaceFolder}/source/*.cpp", //all cpp from source"-I", //include"${workspaceFolder}/include", //include path"-o","${workspaceFolder}/out/${fileBasenameNoExtension}" //out path],"options": {"cwd": "${fileDirname}"},"problemMatcher": ["$gcc"],"group": {"kind": "build","isDefault": true},"detail": "Task generated by Debugger."}],"version": "2.0.0"
}

修改launch.json

默认的launch.json如下，
只需要修改2版主即可

1. “program” 后的属性，修改成与tasks.json -o 后的属性一样
2. “cwd”: 属性修改为 “${workspaceFolder}/out”

{// Use IntelliSense to learn about possible attributes.// Hover to view descriptions of existing attributes.// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387"version": "0.2.0","configurations": [{"name": "g++ - Build and debug active file","type": "cppdbg","request": "launch","program": "${fileDirname}/${fileBasenameNoExtension}","args": [],"stopAtEntry": false,"cwd": "${fileDirname}","environment": [],"externalConsole": false,"MIMode": "gdb","setupCommands": [{"description": "Enable pretty-printing for gdb","text": "-enable-pretty-printing","ignoreFailures": true}],"preLaunchTask": "C/C++: g++ build active file","miDebuggerPath": "/usr/bin/gdb"}]
}

修改如下，都已经加注释了

{// Use IntelliSense to learn about possible attributes.// Hover to view descriptions of existing attributes.// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387"version": "0.2.0","configurations": [{"name": "g++ - Build and debug active file","type": "cppdbg","request": "launch","program": "${workspaceFolder}/out/${fileBasenameNoExtension}", //program output name, same as tasks.json -o path"args": [],"stopAtEntry": false,"cwd": "${workspaceFolder}/out", //out here is the folder named out"environment": [],"externalConsole": false,"MIMode": "gdb","setupCommands": [{"description": "Enable pretty-printing for gdb","text": "-enable-pretty-printing","ignoreFailures": true}],"preLaunchTask": "C/C++: g++ build active file","miDebuggerPath": "/usr/bin/gdb"}]
}

保存以上文件后，已经不报错了

• F5: 调试程序
• CTRL+F5：运行程序
• ctrl + shift + B (build)

可能遇到的错误

1. collect2: error: ld returned 1 exit status

/usr/bin/g++ -g /mnt/d/tmp/c++/source/main.cpp -I /mnt/d/tmp/c++/include -o /mnt/d/tmp/c++/out/main
/tmp/ccBwxewk.o: In function `main':
/mnt/d/tmp/c++/source/main.cpp:8: undefined reference to `test_add()'
collect2: error: ld returned 1 exit status

tasks.json -g 后面的参数改为 “${workspaceFolder}/source/*.cpp”

2. /mnt/d/tmp/c++/source/add.cpp:3:10: fatal error: add.h: No such file or directory

Starting build...
/usr/bin/g++ -g /mnt/d/tmp/c++/source/*.cpp -o /mnt/d/tmp/c++/out/main
/mnt/d/tmp/c++/source/add.cpp:3:10: fatal error: add.h: No such file or directory#include "add.h"^~~~~~~
compilation terminated.
/mnt/d/tmp/c++/source/main.cpp:2:10: fatal error: add.h: No such file or directory#include <add.h>^~~~~~~
compilation terminated.Build finished with error(s).
The terminal process failed to launch (exit code: -1).

tasks.json 加上"-I", “${workspaceFolder}/include”,

c_cpp_properties.json

c_cpp_properties.json配置文件默认是不会产生的，ctrl+shift+p 再输入configuration选择后便会出现。

在这里我们可以设置 includePath

{"configurations": [{"name": "Linux","includePath": ["${workspaceFolder}/**","${workspaceFolder}/include/**"  //your include path],"defines": [],"compilerPath": "/usr/bin/gcc","cStandard": "gnu11","cppStandard": "gnu++14","intelliSenseMode": "linux-gcc-x64"}],"version": 4
}

注：请注意，这里使用是的WSL环境下的g++。