error[E0038]: the trait `Trait` cannot be made into an object --> $DIR/associated-const-in-trait.rs:7:6 | LL | impl dyn Trait { | ^^^^^^^^^ `Trait` cannot be made into an object | note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit --> $DIR/associated-const-in-trait.rs:4:11 | LL | trait Trait { | ----- this trait cannot be made into an object... LL | const N: usize; | ^ ...because it contains this associated `const` = help: consider moving `N` to another trait error: aborting due to previous error For more information about this error, try `rustc --explain E0038`.