plugins/topology: use memleak annotation instead of global_gossmap hammer.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

plugins/topology.c

@@ -684,6 +684,14 @@ done:
 	return command_finished(cmd, js);
 }
 
+#if DEVELOPER
+static void memleak_mark(struct plugin *p, struct htable *memtable)
+{
+	memleak_remove_region(memtable, global_gossmap,
+			      tal_bytelen(global_gossmap));
+}
+#endif
+
 static const char *init(struct plugin *p,
 			const char *buf UNUSED, const jsmntok_t *config UNUSED)
 {
@@ -694,9 +702,9 @@ static const char *init(struct plugin *p,
 		 take(json_out_obj(NULL, NULL, NULL)),
 		 "{id:%}", JSON_SCAN(json_to_node_id, &local_id));
 
-	global_gossmap = notleak_with_children(gossmap_load(NULL,
+	global_gossmap = gossmap_load(NULL,
 				      GOSSIP_STORE_FILENAME,
-					    &num_cupdates_rejected));
+				      &num_cupdates_rejected);
 	if (!global_gossmap)
 		plugin_err(plugin, "Could not load gossmap %s: %s",
 			   GOSSIP_STORE_FILENAME, strerror(errno));
@@ -705,6 +713,9 @@ static const char *init(struct plugin *p,
 		plugin_log(plugin, LOG_DBG,
 			   "gossmap ignored %zu channel updates",
 			   num_cupdates_rejected);
+#if DEVELOPER
+	plugin_set_memleak_handler(p, memleak_mark);
+#endif
 	return NULL;
 }
 

tests/test_gossip.py

@@ -1966,6 +1966,22 @@ def test_addgossip(node_factory):
         l3.rpc.addgossip(badupdate)
 
 
+def test_topology_leak(node_factory, bitcoind):
+    l1, l2, l3 = node_factory.line_graph(3)
+
+    l1.rpc.listchannels()
+    bitcoind.generate_block(5)
+
+    # Wait until l1 sees all the channels.
+    wait_for(lambda: len(l1.rpc.listchannels()['channels']) == 4)
+
+    # Close and wait for gossip to catchup.
+    txid = l2.rpc.close(l3.info['id'])['txid']
+    bitcoind.generate_block(1, txid)
+
+    wait_for(lambda: len(l1.rpc.listchannels()['channels']) == 2)
+
+
 def test_parms_listforwards(node_factory):
     """
     Simple test to ensure that the order of the listforwards