diff --git a/smallchat-server.c b/smallchat-server.c
index 67b1589..e15d38b 100644
--- a/smallchat-server.c
+++ b/smallchat-server.c
@@ -82,6 +82,7 @@ struct client *createClient(int fd) {
     c->fd = fd;
     c->nick = chatMalloc(nicklen+1);
     memcpy(c->nick,nick,nicklen);
+    assert(c->fd < MAX_CLIENTS);
     assert(Chat->clients[c->fd] == NULL); // This should be available.
     Chat->clients[c->fd] = c;
     /* We need to update the max client set if needed. */