diff --git a/oc2/ocnode.c b/oc2/ocnode.c
index 5df3ebdd2..46604837a 100644
--- a/oc2/ocnode.c
+++ b/oc2/ocnode.c
@@ -482,6 +482,8 @@ occorrelater(OCnode* dds, OCnode* dxd)
     if(dxd->name != NULL && dxd->name != NULL
        && strcmp(dxd->name,dds->name) != 0) {
 	OCTHROWCHK((ocstat = OC_EINVAL)); goto fail;
+    } else if(dxd->name != dds->name) { /* test NULL==NULL */
+	OCTHROWCHK((ocstat = OC_EINVAL)); goto fail;
     }
 
     if(dxd->array.rank != dds->array.rank) {