https://bugs.winehq.org/show_bug.cgi?id=37076
--- Comment #2 from Vincent Povirk madewokherd@gmail.com --- MS's Managed C++ compiler has been known to generate unreachable ret instructions with the stack empty, which is technically invalid but .NET copes with it. I don't know if that's the case here. We have a hack for this in Wine Mono, but it may be incomplete.
The code from that method might be useful, but I don't know an easy way to extract it.