Index: generic/nsf.c
===================================================================
diff -u -r841e805480b4e7d445a61269249de9007112320d -rc3ec5a3a8cd0de894d2bea94f5a0d38eed7bdb9c
--- generic/nsf.c	(.../nsf.c)	(revision 841e805480b4e7d445a61269249de9007112320d)
+++ generic/nsf.c	(.../nsf.c)	(revision c3ec5a3a8cd0de894d2bea94f5a0d38eed7bdb9c)
@@ -23675,7 +23675,7 @@
 static int
 NsfCGetCachendParameters(Tcl_Interp *interp, NsfClass *class) {
 
-  if (likely(class && class->parsedParamPtr)) {
+  if (likely(class && class->parsedParamPtr && class->parsedParamPtr->paramDefs)) {
     Tcl_Obj *listObj;
 
     listObj = ListParamDefs(interp, class->parsedParamPtr->paramDefs->paramsPtr, NSF_PARAMS_PARAMETER);