diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 38cac07913..603a4ad652 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -28785,9 +28785,9 @@ virDomainDefCompatibleDevice(virDomainDefPtr def,
 
     if (action == VIR_DOMAIN_DEVICE_ACTION_UPDATE &&
         live &&
-        ((!!data.newInfo != !!data.oldInfo) ||
-         (data.newInfo && data.oldInfo &&
-          STRNEQ_NULLABLE(data.newInfo->alias, data.oldInfo->alias)))) {
+        (data.newInfo && data.oldInfo &&
+         data.newInfo->alias && data.oldInfo->alias &&
+         STRNEQ(data.newInfo->alias, data.oldInfo->alias))) {
         virReportError(VIR_ERR_OPERATION_DENIED, "%s",
                        _("changing device alias is not allowed"));
         return -1;