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//! If visibility is assumed, a transmutation should be accepted even if the
//! destination type contains an unreachable field (e.g., a public field with a
//! private type). (This rule is distinct from type privacy, which still may
//! forbid naming such types.)
#![crate_type = "lib"]
#![feature(transmutability)]
#![allow(dead_code)]
mod assert {
use std::mem::{Assume, BikeshedIntrinsicFrom};
pub fn is_transmutable<Src, Dst, Context>()
where
Dst: BikeshedIntrinsicFrom<Src, Context, { Assume::SAFETY }>
// safety IS assumed --------------------^^^^^^^^^^^^^^^^^^
{}
}
mod src {
#[repr(C)] pub(self) struct Zst;
#[repr(C)] pub(in super) struct Src {
pub(self) field: Zst,
}
}
mod dst {
#[repr(C)] pub(self) struct Zst; // <- unreachable type
#[repr(C)] pub(in super) struct Dst {
pub(in super) field: Zst, //~ ERROR private type
}
}
fn test() {
struct Context;
assert::is_transmutable::<src::Src, dst::Dst, Context>();
}
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