VS Code will not build c++ programs with multiple .ccp source files

feeling lazy,

This is tasks.json of vscode for linux distros, to compile multiple cpp files.

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

This is a Windows answer for the same problem:

I was struggling with this as well until I found the following answer at https://code.visualstudio.com/docs/cpp/config-mingw :

You can modify your tasks.json to build multiple C++ files by using an argument like "${workspaceFolder}\\*.cpp" instead of ${file}. This will build all .cpp files in >your current folder. You can also modify the output filename by replacing "${fileDirname}\\${fileBasenameNoExtension}.exe" with a hard-coded filename (for >example "${workspaceFolder}\\myProgram.exe").

Note that the F in workspaceFolder is capitalized.

As an example, in my tasks.json file in my project, the text in between the brackets under "args" originally appeared as follows:

"-g",
  "${file}",
  "-o",
  "${fileDirname}\\${fileBasenameNoExtension}.exe"

This gave me reference errors because it was only compiling one and not both of my files.

However, I was able to get the program to work after changing that text to the following:

"-g",
"${workspaceFolder}\\*.cpp",
"-o",
"${fileDirname}\\${fileBasenameNoExtension}.exe"

in tasks.json:

        "label": "g++.exe build active file",
        "args": [
            "-g",
            "${fileDirname}\\**.cpp",
            //"${fileDirname}\\**.h",
            "-o",
            "${fileDirname}\\${fileBasenameNoExtension}.exe",
        ],

in launch.json:

"preLaunchTask": "g++.exe build active file"

it will work if your sources are in separated folder

If you have multiple files and one depends on a cpp file for another, you need to tell g++ to compile it as well, so the linker can find it. The simplest way would be:

$ g++ Cat.cpp main.cpp -o Classes

---

^{As a side note, you should probably compile with warnings, minimally -Wall, likely -Wextra, and possibly -Wpedantic, so you know if something you're doing is problematic.}