Negative domain id on some systems

For some strings the domain id will be negative, causing errors when assigning nodes to domains.
The code that causes it is in Drupal\domain\Entity\Domain:

public function createDomainId() {
    // We cannot reliably use sequences (1, 2, 3) because those can be different
    // across environments. Instead, we use the crc32 hash function to create a
    // unique numeric id for each domain.
    $this->domain_id = (int) crc32($this->getHostname());
  }
 

I think another hash function is needed.