error[E0119]: conflicting implementations of trait `Foo<_>` for type `[isize; 0]`
  --> $DIR/impl-unused-tps.rs:28:1
   |
LL | impl<T> Foo<T> for [isize; 0] {
   | ----------------------------- first implementation here
...
LL | impl<T, U> Foo<T> for U {
   | ^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `[isize; 0]`

error[E0119]: conflicting implementations of trait `Bar`
  --> $DIR/impl-unused-tps.rs:40:1
   |
LL |   impl<T, U> Bar for T {
   |   -------------------- first implementation here
...
LL | / impl<T, U> Bar for T
LL | | where
LL | |     T: Bar<Out = U>,
   | |____________________^ conflicting implementation

error[E0119]: conflicting implementations of trait `Foo<[isize; 0]>` for type `[isize; 0]`
  --> $DIR/impl-unused-tps.rs:49:1
   |
LL |   impl<T> Foo<T> for [isize; 0] {
   |   ----------------------------- first implementation here
...
LL | / impl<T, U, V> Foo<T> for T
LL | | where
LL | |     (T, U): Bar<Out = V>,
   | |_________________________^ conflicting implementation for `[isize; 0]`

error[E0119]: conflicting implementations of trait `Foo<([isize; 0], _)>` for type `[isize; 0]`
  --> $DIR/impl-unused-tps.rs:61:1
   |
LL |   impl<T> Foo<T> for [isize; 0] {
   |   ----------------------------- first implementation here
...
LL | / impl<T, U, V> Foo<(T, U)> for T
LL | | where
LL | |     (T, U): Bar<Out = V>,
   | |_________________________^ conflicting implementation for `[isize; 0]`

error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
  --> $DIR/impl-unused-tps.rs:13:9
   |
LL | impl<T, U> Foo<T> for [isize; 1] {
   |         ^ unconstrained type parameter

error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
  --> $DIR/impl-unused-tps.rs:32:9
   |
LL | impl<T, U> Bar for T {
   |         ^ unconstrained type parameter

error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
  --> $DIR/impl-unused-tps.rs:40:9
   |
LL | impl<T, U> Bar for T
   |         ^ unconstrained type parameter

error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
  --> $DIR/impl-unused-tps.rs:49:9
   |
LL | impl<T, U, V> Foo<T> for T
   |         ^ unconstrained type parameter

error[E0207]: the type parameter `V` is not constrained by the impl trait, self type, or predicates
  --> $DIR/impl-unused-tps.rs:49:12
   |
LL | impl<T, U, V> Foo<T> for T
   |            ^ unconstrained type parameter

error: aborting due to 9 previous errors

Some errors have detailed explanations: E0119, E0207.
For more information about an error, try `rustc --explain E0119`.