8 const fn foo(&mut self, x: u32) {
10 //~^ contains unimplemented expression
15 let mut s = S { state: 42 };
16 s.foo(3); //~ ERROR references in constants may only refer to immutable values
23 //~^ ERROR references in constants may only refer to immutable values
25 //~^ ERROR constant contains unimplemented expression type
30 assert_eq!(FOO.state, 3);