diff --git a/src/kike.c b/src/kike.c
index 75537d6..3202333 100644
--- a/src/kike.c
+++ b/src/kike.c
@@ -681,9 +681,10 @@ client_unregister (struct client *c, const char *reason)
 
 	struct str_map_iter iter;
 	str_map_iter_init (&iter, &c->ctx->channels);
-	struct channel *chan;
-	while ((chan = str_map_iter_next (&iter)))
+	struct channel *chan, *next = str_map_iter_next (&iter);
+	for (chan = next; chan; chan = next)
 	{
+		next = str_map_iter_next (&iter);
 		struct channel_user *user;
 		if (!(user = channel_get_user (chan, c)))
 			continue;