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#![crate_type = "lib"]
#![feature(transmutability)]
#![allow(dead_code, incomplete_features, non_camel_case_types)]
use std::mem::MaybeUninit;
mod assert {
use std::mem::{Assume, TransmuteFrom};
pub fn is_maybe_transmutable<Src, Dst>()
where
Dst: TransmuteFrom<Src, { Assume::SAFETY }>
{}
}
fn validity() {
// An initialized byte is a valid uninitialized byte.
assert::is_maybe_transmutable::<u8, MaybeUninit<u8>>();
// An uninitialized byte is never a valid initialized byte.
assert::is_maybe_transmutable::<MaybeUninit<u8>, u8>(); //~ ERROR: cannot be safely transmuted
}
fn padding() {
#[repr(align(8))]
struct Align8;
#[repr(u8)]
enum ImplicitlyPadded {
A(Align8),
}
#[repr(u8)]
enum V0 {
V0 = 0,
}
#[repr(C)]
struct ExplicitlyPadded(V0, MaybeUninit<[u8; 7]>);
assert::is_maybe_transmutable::<ExplicitlyPadded, ImplicitlyPadded>();
assert::is_maybe_transmutable::<ImplicitlyPadded, ExplicitlyPadded>();
}
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