// run-rustfix use std::collections::HashMap; fn main() { let tmp: Box<_>; let mut buggy_map: HashMap = HashMap::new(); let binding = Box::new(1); buggy_map.insert(42, &*binding); //~ ERROR temporary value dropped while borrowed // but it is ok if we use a temporary tmp = Box::new(2); buggy_map.insert(43, &*tmp); }