使用async / await和TaskCompletionSource进行奇怪的堆栈跟踪增长

The following C# code:

以下C＃代码：

class Program
{
    static readonly List<TaskCompletionSource<bool>> buffer = 
                new List<TaskCompletionSource<bool>>();
    static Timer timer;

    public static void Main()
    {
        var outstanding = Enumerable.Range(1, 10)
            .Select(Enqueue)
            .ToArray();

        timer = new Timer(x => Flush(), null, 
                         TimeSpan.FromSeconds(1),
                         TimeSpan.FromMilliseconds(-1));
        try
        {
            Task.WaitAll(outstanding);
        }
        catch {}

        Console.ReadKey();
    }

    static Task Enqueue(int i)
    {
        var task = new TaskCompletionSource<bool>();
        buffer.Add(task);
        return task.Task;
    }

    static void Flush()
    {
        try
        {
            throw new ArgumentException("test");
        }
        catch (Exception e)
        {
            foreach (var each in buffer)
            {
                var lenBefore = e.StackTrace.Length;
                each.TrySetException(e);
                var lenAfter = e.StackTrace.Length;
                Console.WriteLine($"Before - After: {lenBefore} - {lenAfter}");
                Console.WriteLine(e.StackTrace);

            }
        }
    }
}
class Progra