How run build task automatically before debugging in Visual Studio Code?

Question

In VS Code I have to run the build task first and then start debugging, while in CLion I just click debug, then it builds automatically if necessary and starts debugging. Is there a way to automate this in VS Code as well?

Answer 1

It took me some time to understand the accepted answer. It was not clear to me from that explanation the exact way that would make my program build and debug with 1 click. Also I'm using Mingw-w64 in Windows. Following the instructions on this link and based on the accepted answer I created the following files:

launch.json:

{
    // 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": "(gdb) Launch",
            "type": "cppdbg",
            "request": "launch",
            "program": "${fileDirname}\\${fileBasenameNoExtension}.exe",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${fileDirname}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb",
            "miDebuggerPath": "C:\\msys64\\mingw64\\bin\\gdb.exe",
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                }
            ],
            
            "preLaunchTask": "build"
        }
    ]
}

tasks.json:

{
    "version": "2.0.0",
    "tasks": [
        {
            "type": "cppbuild",
            "label": "build",
            "command": "C:\\msys64\\mingw64\\bin\\g++.exe",
            "args": [
                "-fdiagnostics-color=always",
                "-g",
                "${file}",
                "-o",
                "${fileDirname}\\${fileBasenameNoExtension}.exe"
            ],
            "options": {
                "cwd": "${fileDirname}"
            },
            "problemMatcher": [
                "$gcc"
            ],
            "group": "build",
            "detail": "compiler: C:\\msys64\\mingw64\\bin\\g++.exe"
        }
    ]
}

The key aspect is to rename the default "label": "C/C++: g++.exe build active file" in tasks.json, for something else, for instance I used the word "build" and later reference that same word (not the path or link to tasks.json) in "preLaunchTask": "build" inside launch.json.

Notice the renaming is not strictly necessary. You can also say "preLaunchTask": "C/C++: g++.exe build active file" inside launch.json and it will also work.