error[E0277]: the size for values of type `[u8]` cannot be known at compilation time --> $DIR/path-by-value.rs:3:9 | LL | fn f(p: Path) { } | ^^^^ doesn't have a size known at compile-time | = help: within `Path`, the trait `Sized` is not implemented for `[u8]`, which is required by `Path: Sized` note: required because it appears within the type `Path` --> $SRC_DIR/std/src/path.rs:LL:COL = help: unsized fn params are gated as an unstable feature help: function arguments must have a statically known size, borrowed types always have a known size | LL | fn f(p: &Path) { } | + error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0277`.