Running gdbserver as a `preLaunchTask` - need to press start/stop button several times

• VSCode Version: Code 1.14.0 (b8cd5b9556d8b70ea560d35b903422363f6c5c40, 2017-07-10T20:36:40.018Z)
• OS Version: Linux x64 4.4.0-53-generic
• Extensions:

Hello. Thank you for the great tool - I'm using vscode/cpptools everyday and happy with it.

Now to the problem. I have the following task in tasks.json:

{
    "taskName": "docker build&run",
    "linux": {
        "args": [
            "\"docker run --rm --privileged -p 2222:2222 -v ~/path/:/path/ -w /path/build cpp_tools bash -c 'cmake --build . && gdbserver localhost:2222 ./app'\""
        ]
    },
    "group": {
        "kind": "build",
        "isDefault": true
    }
}

As you can see, it starts a docker container that builds an executable and runs gdbserver inside.

Here's my launch.json:

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "(gdb) remote",
            "type": "cppdbg",
            "request": "launch",
            "preLaunchTask": "docker build&run",
            "program": "${workspaceRoot}/build/app",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceRoot}/build",
            "environment": [],
            "externalConsole": true,
            "MIMode": "gdb",
            "miDebuggerServerAddress": "localhost:2222",
            "sourceFileMap": {
                "/path/": "~/path/"
            },
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                }
            ]
        }
    ]
}

I want to build an app and start the debug session with F5 button. The problem is that I need to press F5 twice - the first press builds an app and starts the debug server in docker container and the second press launches my application (which successfully connects). The problem appears both for F5 and Start Debugging button in GUI.
Also I have to press stop button 3 (three) times in order to stop an application (both for Shift+F5 and the Stop button in GUI).

Reproduce el comportamiento utilizando las configuraciones tasks.json y launch.json, pulsando F5 y deteniendo después la sesión como se describe. Empieza trazando el ciclo de vida de preLaunchTask y de la sesión de depuración en la extensión; se considera terminado cuando una pulsación de F5 inicia la tarea y el depurador, y una acción de detención finaliza la aplicación y el servidor.