diff --git a/src/util/virutil.c b/src/util/virutil.c
index 8d2f62a20cfc60768dfb1b0062f29fafeb61b7ec..519796928c372b60dbcab1493df820c58995ab29 100644
--- a/src/util/virutil.c
+++ b/src/util/virutil.c
@@ -1063,6 +1063,7 @@ virGetGroupList(uid_t uid, gid_t gid, gid_t **list)
 
     ret = mgetgroups(user, primary, list);
     if (ret < 0) {
+        sa_assert(!*list);
         virReportSystemError(errno,
                              _("cannot get group list for '%s'"), user);
         goto cleanup;