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//! A struct must have a well-defined layout to participate in a transmutation.
#![crate_type = "lib"]
#![feature(transmutability)]
#![allow(dead_code, incomplete_features, non_camel_case_types)]
mod assert {
use std::mem::{Assume, BikeshedIntrinsicFrom};
pub struct Context;
pub fn is_maybe_transmutable<Src, Dst>()
where
Dst: BikeshedIntrinsicFrom<Src, Context, {
Assume {
alignment: true,
lifetimes: true,
safety: true,
validity: true,
}
}>
{}
}
fn should_reject_repr_rust()
{
union repr_rust {
a: u8
}
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn should_accept_repr_C()
{
#[repr(C)]
union repr_c {
a: u8
}
struct repr_rust;
assert::is_maybe_transmutable::<repr_c, ()>();
assert::is_maybe_transmutable::<u128, repr_c>();
}
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