1 error[E0277]: the size for values of type `impl ?Sized` cannot be known at compilation time
2 --> $DIR/rpit-not-sized.rs:1:13
4 LL | fn foo() -> impl ?Sized {
5 | ^^^^^^^^^^^ doesn't have a size known at compile-time
7 = help: the trait `Sized` is not implemented for `impl ?Sized`
8 = note: the return type of a function must have a statically known size
10 error: aborting due to previous error
12 For more information about this error, try `rustc --explain E0277`.