Index: generic/nsf.c
===================================================================
diff -u -r2b63021196c8886e61e032e05deb4d5c9c1f01e6 -rf4077b427aade0dc3e4c6c1218df736b66ec6c7f
--- generic/nsf.c	(.../nsf.c)	(revision 2b63021196c8886e61e032e05deb4d5c9c1f01e6)
+++ generic/nsf.c	(.../nsf.c)	(revision f4077b427aade0dc3e4c6c1218df736b66ec6c7f)
@@ -15585,8 +15585,17 @@
                            ObjectName_(object), methodName);
     }
   }
+
+
+  /* TODO: Is this guarding too excessive, or just fine? */
   methodObjTypePtr = methodObj->typePtr;
-  ccCtxPtr = methodObj->internalRep.twoPtrValue.ptr2;
+  if (methodObjTypePtr == Nsf_OT_tclCmdNameType
+      || methodObjTypePtr == &NsfInstanceMethodObjType
+      || methodObjTypePtr == &NsfObjectMethodObjType) {
+    ccCtxPtr = methodObj->internalRep.twoPtrValue.ptr2;
+  } else {
+    ccCtxPtr = NULL;
+  }
 
 
 #if 1