rust/src/test/ui/no_send-enum.rs
Niko Matsakis fda3378e3f introduce negative_impls feature gate and document
They used to be covered by `optin_builtin_traits` but negative impls
are now applicable to all traits, not just auto traits.

This also adds docs in the unstable book for the current state of auto traits.
2020-03-26 06:52:55 -04:00

19 lines
264 B
Rust

#![feature(negative_impls)]
use std::marker::Send;
struct NoSend;
impl !Send for NoSend {}
enum Foo {
A(NoSend)
}
fn bar<T: Send>(_: T) {}
fn main() {
let x = Foo::A(NoSend);
bar(x);
//~^ ERROR `NoSend` cannot be sent between threads safely
}