diff --git a/unit/test-gatt.c b/unit/test-gatt.c
index 12b1919..9a77e09 100644
--- a/unit/test-gatt.c
+++ b/unit/test-gatt.c
@@ -736,11 +736,11 @@ static void test_server(gconstpointer data)
 
 	len = write(context->fd, pdu.data, pdu.size);
 
+	g_assert_cmpint(len, ==, pdu.size);
+
 	if (g_test_verbose())
 		util_hexdump('<', pdu.data, len, test_debug, "GATT: ");
 
-	g_assert_cmpint(len, ==, pdu.size);
-
 	execute_context(context);
 }