ring/polyfill/notsend.rs
1// Copyright 2024 Brian Smith.
2//
3// Permission to use, copy, modify, and/or distribute this software for any
4// purpose with or without fee is hereby granted, provided that the above
5// copyright notice and this permission notice appear in all copies.
6//
7// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
14
15use crate::testutil;
16use core::{marker::PhantomData, mem::size_of};
17
18/// A ZST that can be added to any type to make the type `!Send`.
19#[derive(Clone, Copy)]
20pub struct NotSend(PhantomData<*mut ()>);
21
22impl NotSend {
23 pub const VALUE: Self = Self(PhantomData);
24}
25
26#[allow(deprecated)]
27const _: () = testutil::compile_time_assert_clone::<NotSend>();
28#[allow(deprecated)]
29const _: () = testutil::compile_time_assert_copy::<NotSend>();
30const _: () = assert!(size_of::<NotSend>() == 0);