error[E0277]: the trait bound `impl Foo<u8>: Foo<char>` is not satisfied
  --> $DIR/return-dont-satisfy-bounds.rs:13:34
   |
LL |     fn foo<F2: Foo<u8>>(self) -> impl Foo<u8> {
   |                                  ^^^^^^^^^^^^ the trait `Foo<char>` is not implemented for `impl Foo<u8>`
   |
   = help: the trait `Foo<char>` is implemented for `Bar`
note: required by a bound in `Foo::{opaque#0}`
  --> $DIR/return-dont-satisfy-bounds.rs:7:30
   |
LL |     fn foo<F2>(self) -> impl Foo<T>;
   |                              ^^^^^^ required by this bound in `Foo::{opaque#0}`

error: aborting due to previous error

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