AddCallback causes deadlock

[luithefirst]

If a cval already has a callback and a new one is added, a deadlock can occur if the cval is changed in another thread:

static ChangeableValue<int> cval = new (1);

static void TestAddCallback()
{
    var running = true;

    cval.AddCallback(_ => { });

    new Thread(new ThreadStart(() => 
    {
        while(running)
        {
            using (Adaptive.Transact)
            {
                Thread.Yield();
                cval.Value = cval.Value + 1;
            }
        }
    })).Start();

    for (int i = 0; i < 1000000; i++)
    {
        var dispose = cval.AddCallback(v => Console.WriteLine("FOOO: {0}", v));
        Thread.Yield();
        dispose.Dispose();
    }
    running = true;

    Console.WriteLine("EXIT");
}

Is there a way to prevent this?

[krauthaufen]

#121