Index: generic/nsf.c
===================================================================
diff -u -r08dedaca6e7654b181f4d33d918bc3b9737fed71 -ra4eaf4e3ffe74b1d29777daf3b048550a5de4c0c
--- generic/nsf.c	(.../nsf.c)	(revision 08dedaca6e7654b181f4d33d918bc3b9737fed71)
+++ generic/nsf.c	(.../nsf.c)	(revision a4eaf4e3ffe74b1d29777daf3b048550a5de4c0c)
@@ -15731,6 +15731,7 @@
 
   } else if (paramPtr->flags & NSF_ARG_ALIAS) {
     Tcl_Obj *methodObj, **ovPtr, *ov0;
+    static Tcl_Obj *constantObj = NULL;
     const char *methodString;
     int oc = 0;
 
@@ -15794,7 +15795,7 @@
       Tcl_Obj **movPtr = NULL;
 
       ov0 = NULL;
-      ovPtr = NULL;
+      ovPtr = &constantObj;
 
       if (Tcl_ListObjGetElements(interp, methodObj, &moc, &movPtr) == TCL_OK) {
         if (moc != 2) {
@@ -15833,6 +15834,8 @@
               paramPtr->nrArgs, ObjStr(newValue));*/
 #if !defined(NDEBUG)
       if (oc > 2) {
+        assert(ovPtr != NULL);
+        assert(ovPtr != &constantObj);
         assert(ISOBJ(ovPtr[oc-2]));
       }
 #endif