Function std::collections::hash_map::raw_table::make_hash

pub fn make_hash<T: ?Sized, S>(hash_state: &S, t: &T) -> SafeHash where T: Hash, S: HashState

We need to remove hashes of 0. That's reserved for empty buckets. This function wraps up hash_keyed to be the only way outside this module to generate a SafeHash.