error[E0311]: the parameter type `U` may not live long enough --> $DIR/async-generics-and-bounds.rs:11:5 | LL | async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash; | ^^^^^^^^^^^^^-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | | | | | the parameter type `U` must be valid for the anonymous lifetime as defined here... | ...so that the reference type `&(T, U)` does not outlive the data it points at | help: consider adding an explicit lifetime bound | LL | async fn foo<'a>(&'a self) -> &'a (T, U) where T: Debug + Sized, U: Hash, U: 'a; | ++++ ++ ++ +++++++ error[E0311]: the parameter type `T` may not live long enough --> $DIR/async-generics-and-bounds.rs:11:5 | LL | async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash; | ^^^^^^^^^^^^^-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | | | | | the parameter type `T` must be valid for the anonymous lifetime as defined here... | ...so that the reference type `&(T, U)` does not outlive the data it points at | help: consider adding an explicit lifetime bound | LL | async fn foo<'a>(&'a self) -> &'a (T, U) where T: Debug + Sized, U: Hash, T: 'a; | ++++ ++ ++ +++++++ error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0311`.