extern crate rlua; use std::panic::catch_unwind; use rlua::Lua; fn main() { let lua = Lua::new(); let table = lua.create_table().unwrap(); let _ = catch_unwind(move || table.set("a", "b").unwrap()); //~^ error: the type `std::cell::UnsafeCell<()>` may contain interior mutability and a reference // may not be safely transferrable across a catch_unwind boundary }