error[E0391]: cycle detected when processing `cycle1::{{opaque}}#0`
  --> $DIR/auto-trait-leak.rs:12:16
   |
LL | fn cycle1() -> impl Clone {
   |                ^^^^^^^^^^
   |
note: ...which requires processing `cycle1`...
  --> $DIR/auto-trait-leak.rs:12:1
   |
LL | fn cycle1() -> impl Clone {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: ...which requires evaluating trait selection obligation `impl std::clone::Clone: std::marker::Send`...
note: ...which requires processing `cycle2::{{opaque}}#0`...
  --> $DIR/auto-trait-leak.rs:21:16
   |
LL | fn cycle2() -> impl Clone {
   |                ^^^^^^^^^^
note: ...which requires processing `cycle2`...
  --> $DIR/auto-trait-leak.rs:21:1
   |
LL | fn cycle2() -> impl Clone {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: ...which requires evaluating trait selection obligation `impl std::clone::Clone: std::marker::Send`...
   = note: ...which again requires processing `cycle1::{{opaque}}#0`, completing the cycle
note: cycle used when checking item types in top-level module
  --> $DIR/auto-trait-leak.rs:1:1
   |
LL | / use std::cell::Cell;
LL | | use std::rc::Rc;
LL | |
LL | | fn send<T: Send>(_: T) {}
...  |
LL | |     Rc::new(String::from("foo"))
LL | | }
   | |_^

error[E0391]: cycle detected when processing `cycle1::{{opaque}}#0`
  --> $DIR/auto-trait-leak.rs:12:16
   |
LL | fn cycle1() -> impl Clone {
   |                ^^^^^^^^^^
   |
note: ...which requires processing `cycle1`...
  --> $DIR/auto-trait-leak.rs:12:1
   |
LL | fn cycle1() -> impl Clone {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: ...which requires evaluating trait selection obligation `impl std::clone::Clone: std::marker::Send`...
note: ...which requires processing `cycle2::{{opaque}}#0`...
  --> $DIR/auto-trait-leak.rs:21:16
   |
LL | fn cycle2() -> impl Clone {
   |                ^^^^^^^^^^
note: ...which requires processing `cycle2`...
  --> $DIR/auto-trait-leak.rs:21:1
   |
LL | fn cycle2() -> impl Clone {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: ...which again requires processing `cycle1::{{opaque}}#0`, completing the cycle
note: cycle used when checking item types in top-level module
  --> $DIR/auto-trait-leak.rs:1:1
   |
LL | / use std::cell::Cell;
LL | | use std::rc::Rc;
LL | |
LL | | fn send<T: Send>(_: T) {}
...  |
LL | |     Rc::new(String::from("foo"))
LL | | }
   | |_^

error[E0277]: `std::rc::Rc<std::string::String>` cannot be sent between threads safely
  --> $DIR/auto-trait-leak.rs:15:5
   |
LL | fn send<T: Send>(_: T) {}
   |    ----    ---- required by this bound in `send`
...
LL |     send(cycle2().clone());
   |     ^^^^ `std::rc::Rc<std::string::String>` cannot be sent between threads safely
   |
   = help: within `impl std::clone::Clone`, the trait `std::marker::Send` is not implemented for `std::rc::Rc<std::string::String>`
   = note: required because it appears within the type `impl std::clone::Clone`

error: aborting due to 3 previous errors

Some errors have detailed explanations: E0277, E0391.
For more information about an error, try `rustc --explain E0277`.