1 error[E0596]: cannot borrow `*a` as mutable, as `a` is not declared as mutable
2 --> $DIR/borrowck-borrow-immut-deref-of-box-as-mut.rs:12:5
4 LL | let a: Box<_> = Box::new(A);
5 | - help: consider changing this to be mutable: `mut a`
7 | ^^^^^^^ cannot borrow as mutable
9 error: aborting due to previous error
11 For more information about this error, try `rustc --explain E0596`.