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//@ check-pass
//! An array must inherit the alignment of its inner type.
#![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
.and(Assume::LIFETIMES)
.and(Assume::SAFETY)
.and(Assume::VALIDITY)
}>
{}
}
#[derive(Clone, Copy)] #[repr(u8)] enum Ox00 { V = 0x00 }
#[derive(Clone, Copy)] #[repr(u8)] enum Ox01 { V = 0x01 }
#[derive(Clone, Copy)] #[repr(u8)] enum OxFF { V = 0xFF }
#[repr(C)]
union Uninit {
a: (),
b: OxFF,
}
#[repr(C, align(2))] struct align_2(Ox00);
fn len_0() {
#[repr(C)] struct ImplicitlyPadded([align_2; 0], Ox01);
#[repr(C)] struct ExplicitlyPadded(Ox01, Uninit);
#[repr(C)] struct Struct();
assert::is_maybe_transmutable::<ImplicitlyPadded, ExplicitlyPadded>();
assert::is_maybe_transmutable::<ExplicitlyPadded, ImplicitlyPadded>();
}
fn len_1() {
#[repr(C)] struct ImplicitlyPadded([align_2; 1], Ox01);
#[repr(C)] struct ExplicitlyPadded(Ox00, Uninit, Ox01, Uninit);
#[repr(C)] struct Struct();
assert::is_maybe_transmutable::<ImplicitlyPadded, ExplicitlyPadded>();
assert::is_maybe_transmutable::<ExplicitlyPadded, ImplicitlyPadded>();
}
fn len_2() {
#[repr(C)] struct ImplicitlyPadded([align_2; 2], Ox01);
#[repr(C)] struct ExplicitlyPadded(Ox00, Uninit, Ox00, Uninit, Ox01, Uninit);
#[repr(C)] struct Struct();
assert::is_maybe_transmutable::<ImplicitlyPadded, ExplicitlyPadded>();
assert::is_maybe_transmutable::<ExplicitlyPadded, ImplicitlyPadded>();
}
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