Possible regression in latest? dmd with inherited inner classes

[Boris-Barboris]

On Tuesday, 14 May 2019 at 15:35:15 UTC, Arafel wrote:
> Hi,
>
> I have found the following regression with the latest dmd:
>
> https://run.dlang.io/is/4KdP5s

Yep, got that thing blocking my upgrade as well.
The issue apparently is quite old though. Here is a bug report:
https://issues.dlang.org/show_bug.cgi?id=16215