// check-pass //! If visibility is assumed, a transmutation should be accepted even if the //! destination type contains a private variant. #![crate_type = "lib"] #![feature(transmutability)] #![allow(dead_code)] mod assert { use std::mem::{Assume, BikeshedIntrinsicFrom}; pub fn is_transmutable() where Dst: BikeshedIntrinsicFrom // safety IS assumed --------------------^^^^^^^^^^^^^^^^^^ {} } mod src { #[repr(C)] pub(self) struct Zst; #[repr(C)] pub(in super) struct Src { pub(self) field: Zst, } } mod dst { #[derive(Copy, Clone)] #[repr(C)] pub(in super) struct Zst; #[repr(C)] pub(in super) union Dst { pub(self) field: Zst, // <- private variant } } fn test() { struct Context; assert::is_transmutable::(); }