Should I mark my iterator with DoesNotReturnAttribute if it never "yield breaks"?

Question

Is the use of DoesNotReturnAttribute here appropriate or not?

[DoesNotReturn]
public static IEnumerable<int> X()
{
    yield return 0;
    yield return 1;
    throw new Exception("Go away");
}

Answer 1

This returns, so no; you can see this here - the [DoesNotReturn] ends up here:

    [System.Runtime.CompilerServices.NullableContext(1)]
    [IteratorStateMachine(typeof(<X>d__0))]
    [DoesNotReturn]
    public static IEnumerable<int> X()
    {
        return new <X>d__0(-2);
    }

where it clearly does return.

This seems like a missing warning, honestly. You would get a warning for simpler scenarios, or if you coded this manually.