node_has_ipv6_addr(const node_t *node)
{
  /* Don't check the ORPort or DirPort, as this function isn't port-specific,
   * and the node might have a valid IPv6 address, yet have a zero
   * ORPort or DirPort.
   */
  if (node->ri && tor_addr_is_valid(&node->ri->ipv6_addr, 0))
    return 1;
  if (node->rs && tor_addr_is_valid(&node->rs->ipv6_addr, 0))
    return 1;
  if (node->md && tor_addr_is_valid(&node->md->ipv6_addr, 0))
    return 1;

  return 0;
}

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