// Verify the binding mode shifts - only when no `&` are auto-dereferenced is the // final default binding mode mutable. fn main() { match &&Some(5i32) { Some(n) => { *n += 1; //~ ERROR cannot assign to `*n` which is behind a `&` reference let _ = n; } None => {}, }; match &mut &Some(5i32) { Some(n) => { *n += 1; //~ ERROR cannot assign to `*n` which is behind a `&` reference let _ = n; } None => {}, }; match &&mut Some(5i32) { Some(n) => { *n += 1; //~ ERROR cannot assign to `*n` which is behind a `&` reference let _ = n; } None => {}, }; }