Description: <short summary of the patch>
 TODO: Put a short summary on the line above and replace this paragraph
 with a longer explanation of this change. Complete the meta-information
 with other relevant fields (see below for details). To make it easier, the
 information below has been extracted from the changelog. Adjust it or drop
 it.
 .
 isc-dhcp (4.3.5-3ubuntu7) bionic; urgency=medium
 .
   * bind-includes.patch: Copied from Debian to fix build with bind
     9.11.3.
Author: Timo Aaltonen <tjaalton@debian.org>

---
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checkout http://dep.debian.net/deps/dep3/ to learn about the format. Here
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Origin: <vendor|upstream|other>, <url of original patch>
Bug: <url in upstream bugtracker>
Bug-Debian: https://bugs.debian.org/<bugnumber>
Bug-Ubuntu: https://launchpad.net/bugs/<bugnumber>
Forwarded: <no|not-needed|url proving that it has been forwarded>
Reviewed-By: <name and email of someone who approved the patch>
Last-Update: 2018-11-08

--- isc-dhcp-4.3.5.orig/server/mdb6.c
+++ isc-dhcp-4.3.5/server/mdb6.c
@@ -1186,7 +1186,7 @@ cleanup_lease6(ia_hash_t *ia_table,
 	 * Remove the old lease from the active heap and from the hash table
 	 * then remove the lease from the IA and clean up the IA if necessary.
 	 */
-	isc_heap_delete(pool->active_timeouts, test_iasubopt->heap_index);
+	if (test_iasubopt->heap_index > 0) isc_heap_delete(pool->active_timeouts, test_iasubopt->heap_index);
 	pool->num_active--;
 	if (pool->ipv6_pond)
 		pool->ipv6_pond->num_active--;
@@ -1258,7 +1258,7 @@ add_lease6(struct ipv6_pool *pool, struc
 		 */
 		if ((test_iasubopt->state == FTS_ACTIVE) ||
 		    (test_iasubopt->state == FTS_ABANDONED)) {
-			isc_heap_delete(pool->active_timeouts,
+			if (test_iasubopt->heap_index > 0) isc_heap_delete(pool->active_timeouts,
 					test_iasubopt->heap_index);
 			pool->num_active--;
 			if (pool->ipv6_pond)
@@ -1270,7 +1270,7 @@ add_lease6(struct ipv6_pool *pool, struc
 					pool->ipv6_pond->num_abandoned--;
 			}
 		} else {
-			isc_heap_delete(pool->inactive_timeouts,
+			if (test_iasubopt->heap_index > 0) isc_heap_delete(pool->inactive_timeouts,
 					test_iasubopt->heap_index);
 			pool->num_inactive--;
 		}
@@ -1399,7 +1399,7 @@ move_lease_to_active(struct ipv6_pool *p
 	if (insert_result == ISC_R_SUCCESS) {
        		iasubopt_hash_add(pool->leases, &lease->addr, 
 				  sizeof(lease->addr), lease, MDL);
-		isc_heap_delete(pool->inactive_timeouts, old_heap_index);
+		if (old_heap_index > 0) isc_heap_delete(pool->inactive_timeouts, old_heap_index);
 		pool->num_active++;
 		pool->num_inactive--;
 		lease->state = FTS_ACTIVE;
@@ -1533,7 +1533,7 @@ move_lease_to_inactive(struct ipv6_pool
 
 		iasubopt_hash_delete(pool->leases, 
 				     &lease->addr, sizeof(lease->addr), MDL);
-		isc_heap_delete(pool->active_timeouts, old_heap_index);
+		if (old_heap_index > 0) isc_heap_delete(pool->active_timeouts, old_heap_index);
 		lease->state = state;
 		pool->num_active--;
 		pool->num_inactive++;
@@ -1884,7 +1884,7 @@ cleanup_old_expired(struct ipv6_pool *po
 			break;
 		}
 
-		isc_heap_delete(pool->inactive_timeouts, tmp->heap_index);
+		if (tmp->heap_index > 0) isc_heap_delete(pool->inactive_timeouts, tmp->heap_index);
 		pool->num_inactive--;
 
 		if (tmp->ia != NULL) {