520 static void dns_query_complete(DnsQuery *q, DnsTransactionState state) {
 521         assert(q);
 522         assert(!DNS_TRANSACTION_IS_LIVE(state));
 523         assert(DNS_TRANSACTION_IS_LIVE(q->state));
 524 
 525         /* Note that this call might invalidate the query. Callers
 526          * should hence not attempt to access the query or transaction
 527          * after calling this function. */
 528 
 529         q->state = state;
 530 
 531         dns_query_stop(q);
 532         if (q->complete)
 533                 q->complete(q);
 534 }

commit c856ef0457c35e9edfdbf085b69ec81c126d48e5
Author: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Date:   Fri May 14 10:49:24 2021 +0200

    resolved: fix braino with reference counting and linked lists
    
    In 0e0fd08fc832b8f42e567d722d388eba086da5ff I added reference counts to keep
    track of the DnsQueryCandidate objects. Unfortunately, dns_query_unref_candidates()
    was written as
    
         while (q->candidates)
               dns_query_candidate_unref(q->candidates);
    
    i.e. it would keep dropping the reference count as many times as needed for it
    to hit 0, making the patch less than fully effective.
    
    dns_query_unref_candidates() is renamed to dns_query_detach_candidates() and
    changed to drop exactly one reference from each of the linked candidates.
[...]