error[E0658]: mutable references are not allowed in constant functions
  --> $DIR/issue-114994-fail.rs:6:27
   |
LL | const fn use_mut_const_fn(_f: &mut fn(&mut String)) {
   |                           ^^
   |
   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable

error[E0658]: mutable references are not allowed in constant functions
  --> $DIR/issue-114994-fail.rs:10:33
   |
LL | const fn use_mut_const_tuple_fn(_f: (fn(), &mut u32)) {
   |                                 ^^
   |
   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0658`.