error: impls that are not considered to overlap may be considered to overlap in the future
  --> $DIR/warn-when-cycle-is-error-in-coherence.rs:13:1
   |
LL | #[derive(PartialEq, Default)]
   |          --------- the second impl is here
...
LL | impl<T, Q> PartialEq<Q> for Interval<T>
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the first impl is here
...
LL |     Q: ?Sized + PartialOrd,
   |                 ---------- this where-clause causes a cycle, but it may be treated as possibly holding in the future, causing the impls to overlap
   |
   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
   = note: for more information, see issue #114040 <https://github.com/rust-lang/rust/issues/114040>
note: the lint level is defined here
  --> $DIR/warn-when-cycle-is-error-in-coherence.rs:1:9
   |
LL | #![deny(coinductive_overlap_in_coherence)]
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error