error[E0277]: the size for values of type `str` cannot be known at compilation time --> $DIR/unsized-binding.rs:2:9 | LL | let x = *""; | ^ doesn't have a size known at compile-time | = help: the trait `Sized` is not implemented for `str` = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.