error[E0277]: `<impl Foo as Foo>::Bar` cannot be sent between threads safely
  --> $DIR/issue-79843-impl-trait-with-missing-bounds-on-async-fn.rs:14:20
   |
LL |     assert_is_send(&bar);
   |     -------------- ^^^^ `<impl Foo as Foo>::Bar` cannot be sent between threads safely
   |     |
   |     required by a bound introduced by this call
   |
   = help: the trait `Send` is not implemented for `<impl Foo as Foo>::Bar`
note: required by a bound in `assert_is_send`
  --> $DIR/issue-79843-impl-trait-with-missing-bounds-on-async-fn.rs:30:22
   |
LL | fn assert_is_send<T: Send>(_: &T) {}
   |                      ^^^^ required by this bound in `assert_is_send`
help: introduce a type parameter with a trait bound instead of using `impl Trait`
   |
LL | async fn run<F: Foo>(_: &(), foo: F) -> std::io::Result<()> where <F as Foo>::Bar: Send {
   |             ++++++++              ~                         +++++++++++++++++++++++++++

error[E0277]: `<impl Foo as Foo>::Bar` cannot be sent between threads safely
  --> $DIR/issue-79843-impl-trait-with-missing-bounds-on-async-fn.rs:24:20
   |
LL |     assert_is_send(&bar);
   |     -------------- ^^^^ `<impl Foo as Foo>::Bar` cannot be sent between threads safely
   |     |
   |     required by a bound introduced by this call
   |
   = help: the trait `Send` is not implemented for `<impl Foo as Foo>::Bar`
note: required by a bound in `assert_is_send`
  --> $DIR/issue-79843-impl-trait-with-missing-bounds-on-async-fn.rs:30:22
   |
LL | fn assert_is_send<T: Send>(_: &T) {}
   |                      ^^^^ required by this bound in `assert_is_send`
help: introduce a type parameter with a trait bound instead of using `impl Trait`
   |
LL | async fn run2<F: Foo>(_: &(), foo: F) -> std::io::Result<()> where <F as Foo>::Bar: Send {
   |              ~~~~~~~~              ~                         +++++++++++++++++++++++++++

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0277`.