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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()
{
fn unit() {
struct repr_rust;
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn tuple() {
struct repr_rust();
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn braces() {
struct repr_rust{}
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn aligned() {
#[repr(align(1))] struct repr_rust{}
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn packed() {
#[repr(packed)] struct repr_rust{}
assert::is_maybe_transmutable::<repr_rust, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_rust>(); //~ ERROR cannot be safely transmuted
}
fn nested() {
struct repr_rust;
#[repr(C)] struct repr_c(repr_rust);
assert::is_maybe_transmutable::<repr_c, ()>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<u128, repr_c>(); //~ ERROR cannot be safely transmuted
}
}
fn should_accept_repr_C()
{
fn unit() {
#[repr(C)] struct repr_c;
assert::is_maybe_transmutable::<repr_c, ()>();
assert::is_maybe_transmutable::<i128, repr_c>();
}
fn tuple() {
#[repr(C)] struct repr_c();
assert::is_maybe_transmutable::<repr_c, ()>();
assert::is_maybe_transmutable::<i128, repr_c>();
}
fn braces() {
#[repr(C)] struct repr_c{}
assert::is_maybe_transmutable::<repr_c, ()>();
assert::is_maybe_transmutable::<i128, repr_c>();
}
}
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