| error[E0284]: type annotations needed | 
 |   --> $DIR/dyn-compatibility-ok-infer-err.rs:19:5 | 
 |    | | 
 | LL |     use_dyn(&()); | 
 |    |     ^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `use_dyn` | 
 |    | | 
 | note: required by a const generic parameter in `use_dyn` | 
 |   --> $DIR/dyn-compatibility-ok-infer-err.rs:14:12 | 
 |    | | 
 | LL | fn use_dyn<const N: usize>(v: &dyn Foo<N>) where [u8; N + 1]: Sized { | 
 |    |            ^^^^^^^^^^^^^^ required by this const generic parameter in `use_dyn` | 
 | help: consider specifying the generic argument | 
 |    | | 
 | LL |     use_dyn::<N>(&()); | 
 |    |            +++++ | 
 |  | 
 | error[E0284]: type annotations needed | 
 |   --> $DIR/dyn-compatibility-ok-infer-err.rs:19:5 | 
 |    | | 
 | LL |     use_dyn(&()); | 
 |    |     ^^^^^^^ --- type must be known at this point | 
 |    |     | | 
 |    |     cannot infer the value of the const parameter `N` declared on the function `use_dyn` | 
 |    | | 
 | note: required for `()` to implement `Foo<_>` | 
 |   --> $DIR/dyn-compatibility-ok-infer-err.rs:8:22 | 
 |    | | 
 | LL | impl<const N: usize> Foo<N> for () { | 
 |    |      --------------  ^^^^^^     ^^ | 
 |    |      | | 
 |    |      unsatisfied trait bound introduced here | 
 |    = note: required for the cast from `&()` to `&dyn Foo<_>` | 
 | help: consider specifying the generic argument | 
 |    | | 
 | LL |     use_dyn::<N>(&()); | 
 |    |            +++++ | 
 |  | 
 | error: aborting due to 2 previous errors | 
 |  | 
 | For more information about this error, try `rustc --explain E0284`. |