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// Repro for <https://github.com/rust-lang/rust/issues/114046#issue-1819720359>.
//@ edition: 2021
//@ revisions: assumptions no_assumptions
//@[assumptions] compile-flags: -Zhigher-ranked-assumptions
//@[assumptions] known-bug: unknown
//@[no_assumptions] known-bug: #110338
use std::marker::PhantomData;
trait Callable<'a>: Send + Sync {
fn callable(data: &'a [u8]);
}
trait Getter<'a>: Send + Sync {
type ItemSize: Send + Sync;
fn get(data: &'a [u8]);
}
struct List<'a, A: Getter<'a>> {
data: &'a [u8],
item_size: A::ItemSize, // Removing this member causes the code to compile
phantom: PhantomData<A>,
}
struct GetterImpl<'a, T: Callable<'a> + 'a> {
p: PhantomData<&'a T>,
}
impl<'a, T: Callable<'a> + 'a> Getter<'a> for GetterImpl<'a, T> {
type ItemSize = ();
fn get(data: &'a [u8]) {
<T>::callable(data);
}
}
struct ConstructableImpl<'a> {
_data: &'a [u8],
}
impl<'a> Callable<'a> for ConstructableImpl<'a> {
fn callable(_: &'a [u8]) {}
}
struct StructWithLifetime<'a> {
marker: &'a PhantomData<u8>,
}
async fn async_method() {}
fn assert_send(_: impl Send + Sync) {}
// This async method ought to be send, but is not
async fn my_send_async_method(_struct_with_lifetime: &mut StructWithLifetime<'_>, data: &Vec<u8>) {
let _named =
List::<'_, GetterImpl<ConstructableImpl<'_>>> { data, item_size: (), phantom: PhantomData };
// Moving the await point above the constructed of _named, causes
// the method to become send, even though _named is Send + Sync
async_method().await;
assert_send(_named);
}
fn dummy(struct_with_lifetime: &mut StructWithLifetime<'_>, data: &Vec<u8>) {
assert_send(my_send_async_method(struct_with_lifetime, data));
}
fn main() {}
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