1 error[E0277]: the size for values of type `[u32]` cannot be known at compilation time
2 --> $DIR/issue-87935-unsized-box-expr.rs:4:30
4 LL | let _x: Box<[u32]> = box { loop {} };
5 | ^^^^^^^^^^^ doesn't have a size known at compile-time
7 = help: the trait `Sized` is not implemented for `[u32]`
8 = note: the type of a box expression must have a statically known size
10 error: aborting due to previous error
12 For more information about this error, try `rustc --explain E0277`.