error[E0599]: no method named `method` found for reference `&impl Sized` in the current scope --> $DIR/would-constrain-opaque.rs:28:11 | LL | x.method(); | ^^^^^^ method not found in `&impl Sized` | = help: items from traits can only be used if the trait is implemented and in scope note: `Trait` defines an item `method`, perhaps you need to implement it --> $DIR/would-constrain-opaque.rs:15:1 | LL | trait Trait: Sized { | ^^^^^^^^^^^^^^^^^^ error[E0599]: no method named `method` found for reference `&impl Sized` in the current scope --> $DIR/would-constrain-opaque.rs:30:11 | LL | x.method(); | ^^^^^^ method not found in `&impl Sized` | = help: items from traits can only be used if the trait is implemented and in scope note: `Trait` defines an item `method`, perhaps you need to implement it --> $DIR/would-constrain-opaque.rs:15:1 | LL | trait Trait: Sized { | ^^^^^^^^^^^^^^^^^^ error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0599`.