diff --git a/tests/qemumonitortestutils.c b/tests/qemumonitortestutils.c
index 956847667c..bca338541c 100644
--- a/tests/qemumonitortestutils.c
+++ b/tests/qemumonitortestutils.c
@@ -878,6 +878,8 @@ qemuMonitorTestNew(bool json,
     qemuMonitorTestPtr test = NULL;
     virDomainChrSourceDef src;
 
+    memset(&src, 0, sizeof(src));
+
     if (!(test = qemuMonitorCommonTestNew(xmlopt, vm, &src)))
         goto error;
 
@@ -915,6 +917,8 @@ qemuMonitorTestNewAgent(virDomainXMLOptionPtr xmlopt)
     qemuMonitorTestPtr test = NULL;
     virDomainChrSourceDef src;
 
+    memset(&src, 0, sizeof(src));
+
     if (!(test = qemuMonitorCommonTestNew(xmlopt, NULL, &src)))
         goto error;