diff --git a/pjlib/src/pjlib-test/activesock.c b/pjlib/src/pjlib-test/activesock.c
index 2eedca0..1051b87 100644
--- a/pjlib/src/pjlib-test/activesock.c
+++ b/pjlib/src/pjlib-test/activesock.c
@@ -318,6 +318,8 @@
 {
     struct tcp_state *st=(struct tcp_state*)pj_activesock_get_user_data(asock);
 
+    PJ_UNUSED_ARG(op_key);
+
     st->sent = 1;
 
     if (sent < 1) {