1 error[E0596]: cannot borrow `*buf` as mutable, as it is behind a `&` reference
2 --> $DIR/issue-40823.rs:3:5
5 | ^^^^^^^^^^^^^^ `buf` is a `&` reference, so the data it refers to cannot be borrowed as mutable
7 help: consider changing this to be a mutable reference
9 LL | let mut buf = &mut [1, 2, 3, 4];
12 error: aborting due to previous error
14 For more information about this error, try `rustc --explain E0596`.