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//@ check-pass
//! The presence of an `align(X)` annotation must be accounted for.
#![crate_type = "lib"]
#![feature(transmutability)]
#![allow(dead_code, incomplete_features, non_camel_case_types)]
mod assert {
use std::mem::{Assume, TransmuteFrom};
pub fn is_maybe_transmutable<Src, Dst>()
where
Dst: TransmuteFrom<Src, {
Assume {
alignment: true,
lifetimes: true,
safety: true,
validity: true,
}
}>
{}
}
fn should_pad_explicitly_packed_field() {
#[derive(Clone, Copy)] #[repr(u8)] enum V0u8 { V = 0 }
#[derive(Clone, Copy)] #[repr(u8)] enum V1u8 { V = 1 }
#[derive(Clone, Copy)] #[repr(u8)] enum V2u8 { V = 2 }
#[derive(Clone, Copy)] #[repr(u32)] enum V3u32 { V = 3 }
pub union Uninit {
a: (),
b: V1u8,
}
#[repr(C, packed(2))]
pub union Packed {
a: [V3u32; 0],
b: V0u8,
}
#[repr(C)] struct ImplicitlyPadded(Packed, V2u8);
#[repr(C)] struct ExplicitlyPadded(V0u8, Uninit, V2u8);
assert::is_maybe_transmutable::<ImplicitlyPadded, ExplicitlyPadded>();
assert::is_maybe_transmutable::<ExplicitlyPadded, ImplicitlyPadded>();
}
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