union U { a: &'static i32, b: usize, } fn fun(U { a }: U) { //~^ ERROR access to union field is unsafe dbg!(*a); } fn main() { fun(U { b: 0 }); let closure = |U { a }| { //~^ ERROR access to union field is unsafe dbg!(*a); }; closure(U { b: 0 }); }