問題

如下圖文件夾

> include: *.h文件
> out: 編譯后的輸出文件夾
> source：*.cpp文件

先看看我們的幾個文件夾里有什么文件，還有文件里有什么內容。

include

• add.h
  • 這里就是add()函數的聲明
  • 還需要要加上 int test_add();這個聲明
    

source

• main.cpp
  • 簡單的一個程序入口
    
• add.cpp
  • 這里是我們主要的程序部分，定義了幾個add()函數。還有test_add()函數
  • 還需要#include “add.h”
    

out

• 現在還沒有編譯過，所以為空

那我們要怎樣配置vscode里的一些環境呢？

配置過程遇到的問題與解決

遇到的問題1

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

說白了，就是test_add這個標識符不能識別（沒有定義），可我們從上面的文件里看到了，該函數都是有的。再往下看，我們一個一個來解決。

解決步驟

1. ctrl + shift + p

然后選擇如下箭頭所指示

出現如下，選擇Debug Anyway

完成這一步了，我們可以參文件下面，會有一個.vscode的文件夾，還有兩個.json的文件。

2. 配置json文件

修改task.json文件

默認的如下，主要要修改三個地方

1. 添加 -I，及-I對應的文件夾 (include)
2. 修改 -o，及-o對文件夾 (out)
3. 修改-g，及-g對應的文件(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

默認的launch.json如下，
只需要修改2版主即可

1. “program” 后的屬性，修改成與tasks.json -o 后的屬性一樣
2. “cwd”: 屬性修改為 “${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，都已經加注釋了

{// 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，已經不報錯了

• F5: 調試程序
• CTRL+F5：運行程序
• ctrl + shift + B (build)

可能遇到的錯誤

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 后面的參數改為 “${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配置文件默認是不會產生的，ctrl+shift+p 再輸入configuration選擇后便會出現。

在這里我們可以設置 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：請注意，這里使用是的WSL環境下的g++。