error: `impl` associated type signature for `Assoc` doesn't match `trait` associated type signature
  --> $DIR/missing-where-clause-on-trait.rs:9:5
   |
LL |     type Assoc<'a, 'b>;
   |     ------------------- expected
...
LL |     type Assoc<'a, 'b> where 'a: 'b = ();
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ found

error: aborting due to previous error