On Wednesday, 17 June 2020 at 22:48:25 UTC, MoonlightSentinel wrote: > But i would agree with you that there is a bug in your initial It's not the bug in my code, > code, the `ref` should be rejected. it's the compiler's bug not rejecting it, given it's current semantics; instead it *silently* treat alias `ref int` as `int`.