+ // SAFETY: this dance is to reapply any Send/Sync marker. I’m not happy about this
+ // approach, given that I used to do it in safe code, but then came a dodgy
+ // future-compatibility warning where_clauses_object_safety, which is spurious for
+ // auto traits but still super annoying (future-compatibility lints seem to mean
+ // your bin crate needs a corresponding allow!). Although I explained my plight¹
+ // and it was all explained and agreed upon, no action has been taken. So I finally
+ // caved and worked around it by doing it this way, which matches what’s done for
+ // std::any², so it’s probably not *too* bad.
+ //
+ // ¹ https://github.com/rust-lang/rust/issues/51443#issuecomment-421988013
+ // ² https://github.com/rust-lang/rust/blob/e7825f2b690c9a0d21b6f6d84c404bb53b151b38/library/alloc/src/boxed.rs#L1613-L1616
+ let clone: Box<dyn CloneAny> = (**self).clone_to_any();
+ let raw: *mut dyn CloneAny = Box::into_raw(clone);
+ unsafe { Box::from_raw(raw as *mut $t) }