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//! An array 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, TransmuteFrom};
pub fn is_maybe_transmutable<Src, Dst>()
where
Dst: TransmuteFrom<Src, {
Assume::ALIGNMENT
.and(Assume::LIFETIMES)
.and(Assume::SAFETY)
.and(Assume::VALIDITY)
}>
{}
}
fn should_reject_repr_rust()
{
fn unit() {
type repr_rust = [String; 0];
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn singleton() {
type repr_rust = [String; 1];
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn duplex() {
type repr_rust = [String; 2];
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()
{
fn unit() {
#[repr(C)] struct repr_c(u8, u16, u8);
type array = [repr_c; 0];
assert::is_maybe_transmutable::<array, ()>();
assert::is_maybe_transmutable::<i128, array>();
}
fn singleton() {
#[repr(C)] struct repr_c(u8, u16, u8);
type array = [repr_c; 1];
assert::is_maybe_transmutable::<array, repr_c>();
assert::is_maybe_transmutable::<repr_c, array>();
}
fn duplex() {
#[repr(C)] struct repr_c(u8, u16, u8);
#[repr(C)] struct duplex(repr_c, repr_c);
type array = [repr_c; 2];
assert::is_maybe_transmutable::<array, duplex>();
assert::is_maybe_transmutable::<duplex, array>();
}
}
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