32 lines
645 B
Rust
32 lines
645 B
Rust
#![allow(suspicious_auto_trait_impls)]
|
|
|
|
struct Always<T, U>(T, U);
|
|
unsafe impl<T, U> Send for Always<T, U> {}
|
|
struct Foo<T, U>(Always<T, U>);
|
|
|
|
trait False {}
|
|
unsafe impl<U: False> Send for Foo<u32, U> {}
|
|
|
|
trait WithAssoc {
|
|
type Output;
|
|
}
|
|
impl<T: Send> WithAssoc for T {
|
|
type Output = Self;
|
|
}
|
|
impl WithAssoc for Foo<u32, ()> {
|
|
type Output = Box<i32>;
|
|
}
|
|
|
|
fn generic<T, U>(v: Foo<T, U>, f: fn(<Foo<T, U> as WithAssoc>::Output) -> i32) {
|
|
//~^ ERROR `Foo<T, U>` cannot be sent between threads safely
|
|
f(foo(v));
|
|
}
|
|
|
|
fn foo<T: Send>(x: T) -> <T as WithAssoc>::Output {
|
|
x
|
|
}
|
|
|
|
fn main() {
|
|
generic(Foo(Always(0, ())), |b| *b);
|
|
}
|