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": "gcc - Build and debug active file",
            "type": "cppdbg",
            "request": "launch",
            "program": "${fileDirname}/${fileBasenameNoExtension}.out",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceFolder}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb",
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                }
            ],
            "preLaunchTask": "gcc build active file",
            "miDebuggerPath": "/usr/bin/gdb"
        }
    ]
}

tasks.json

{
    "tasks": [
        {
            "type": "shell",
            "label": "gcc build active file",
            "command": "/usr/bin/gcc",
            "args": [
                "-g",
                "-Wall",
                "-std=c11",
                "${file}",
                "-o",
                "${fileDirname}/${fileBasenameNoExtension}.out"
            ],
            "options": {
                "cwd": "/usr/bin"
            }
        }
    ],
    "version": "2.0.0"
}