error[E0403]: the name `T1` is already used for a generic parameter in this item's generic parameters
  --> $DIR/gat-trait-path-generic-type-arg.rs:9:12
   |
LL | impl <T, T1> Foo for T {
   |          -- first use of `T1`
LL |
LL |     type F<T1> = &[u8];
   |            ^^ already used

error[E0637]: `&` without an explicit lifetime name cannot be used here
  --> $DIR/gat-trait-path-generic-type-arg.rs:9:18
   |
LL |     type F<T1> = &[u8];
   |                  ^ explicit lifetime name needed here

error[E0207]: the type parameter `T1` is not constrained by the impl trait, self type, or predicates
  --> $DIR/gat-trait-path-generic-type-arg.rs:7:10
   |
LL | impl <T, T1> Foo for T {
   |          ^^ unconstrained type parameter

error: aborting due to 3 previous errors

Some errors have detailed explanations: E0207, E0403, E0637.
For more information about an error, try `rustc --explain E0207`.