diff --git a/quiche/quic/masque/masque_client_bin.cc b/quiche/quic/masque/masque_client_bin.cc
index 08c8bc0..bf3995e 100644
--- a/quiche/quic/masque/masque_client_bin.cc
+++ b/quiche/quic/masque/masque_client_bin.cc
@@ -221,7 +221,7 @@
     while (true) {
       event_loop->RunEventLoopOnce(QuicTime::Delta::FromMilliseconds(50));
     }
-    return 0;
+    QUICHE_NOTREACHED();
   }
 
   for (size_t i = 1; i < urls.size(); ++i) {