1 error[E0723]: mutable references in const fn are unstable
2 --> $DIR/mutable_borrow.rs:3:9
7 = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
8 = help: add `#![feature(const_fn)]` to the crate attributes to enable
10 error[E0723]: mutable references in const fn are unstable
11 --> $DIR/mutable_borrow.rs:12:13
16 = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
17 = help: add `#![feature(const_fn)]` to the crate attributes to enable
19 error: aborting due to 2 previous errors
21 For more information about this error, try `rustc --explain E0723`.