diff --git a/test_regress/t/t_class_param.out b/test_regress/t/t_class_param.out
index d26ff93f1..e232809d9 100644
--- a/test_regress/t/t_class_param.out
+++ b/test_regress/t/t_class_param.out
@@ -1,14 +1,5 @@
-%Error-UNSUPPORTED: t/t_class_param.v:22:11: Unsupported: parameterized classes
-                                           : ... In instance t
-   22 |    Cls #(.P(4)) c4;
-      |           ^
+%Error-UNSUPPORTED: t/t_class_param.v:18:30: Unsupported: class parameters
+   18 |    localparam P = PMINUS1 + 1;
+      |                              ^
                     ... For error description see https://verilator.org/warn/UNSUPPORTED?v=latest
-%Error-UNSUPPORTED: t/t_class_param.v:7:23: Unsupported: class parameters
-                                          : ... In instance t
-    7 | class Cls #(parameter P = 12);
-      |                       ^
-%Error-UNSUPPORTED: t/t_class_param.v:17:14: Unsupported: parameterized classes
-                                           : ... In instance t
-   17 | typedef Cls#(5) Cls5_t;
-      |              ^
 %Error: Exiting due to
diff --git a/test_regress/t/t_class_param.v b/test_regress/t/t_class_param.v
index b39eb395f..bb1dd29b3 100644
--- a/test_regress/t/t_class_param.v
+++ b/test_regress/t/t_class_param.v
@@ -14,26 +14,41 @@ class Cls #(parameter P = 12);
    endfunction
 endclass
 
+class Wrap #(parameter PMINUS1 = 3);
+   localparam P = PMINUS1 + 1;
+   Cls#(P) c1;
+   function int get_p;
+      return c1.get_p();
+   endfunction
+endclass
+
 typedef Cls#(5) Cls5_t;
 
+// See also t_class_param_mod.v
+
 module t (/*AUTOARG*/);
 
    Cls c12;
    Cls #(.P(4)) c4;
    Cls5_t c5;
-
+   Wrap #(.PMINUS1(15)) w16;
+  
    initial begin
       c12 = new;
       c4 = new;
       c5 = new;
+      w16 = new;
       if (c12.P != 12) $stop;
       if (c4.P != 4) $stop;
       if (c5.P != 5) $stop;
       if (c12.get_p() != 12) $stop;
       if (c4.get_p() != 4) $stop;
+      if (c5.get_p() != 5) $stop;
+      if (w16.get_p() != 16) $stop;
       // verilator lint_off WIDTH
       c12.member = 32'haaaaaaaa;
       c4.member = 32'haaaaaaaa;
+      c5.member = 32'haaaaaaaa;
       // verilator lint_on WIDTH
       if (c12.member != 12'haaa) $stop;
       if (c4.member != 4'ha) $stop;
diff --git a/test_regress/t/t_class_param_mod.pl b/test_regress/t/t_class_param_mod.pl
new file mode 100755
index 000000000..a2ed99042
--- /dev/null
+++ b/test_regress/t/t_class_param_mod.pl
@@ -0,0 +1,22 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2020 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(simulator => 1);
+
+compile(
+    fails => $Self->{vlt_all},
+    );
+
+execute(
+    check_finished => 1,
+    ) if !$Self->{vlt_all};
+
+ok(1);
+1;
diff --git a/test_regress/t/t_class_param_mod.v b/test_regress/t/t_class_param_mod.v
new file mode 100644
index 000000000..1ab090625
--- /dev/null
+++ b/test_regress/t/t_class_param_mod.v
@@ -0,0 +1,63 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed under the Creative Commons Public Domain, for
+// any use, without warranty, 2020 by Wilson Snyder.
+// SPDX-License-Identifier: CC0-1.0
+
+// See also t_class_param.v
+
+module t (/*AUTOARG*/);
+
+class Cls #(parameter P = 12);
+   bit [P-1:0] member;
+   function bit [P-1:0] get_member;
+      return member;
+   endfunction
+   function int get_p;
+      return P;
+   endfunction
+endclass
+
+class Wrap #(parameter PMINUS1 = 3);
+   localparam P = PMINUS1 + 1;
+   Cls#(P) c1;
+   function int get_p;
+      return c1.get_p();
+   endfunction
+endclass
+
+   typedef Cls#(5) Cls5_t;
+
+   Cls c12;
+   Cls #(.P(4)) c4;
+   Cls5_t c5;
+   Wrap #(.PMINUS1(15)) w16;
+  
+   initial begin
+      c12 = new;
+      c4 = new;
+      c5 = new;
+      w16 = new;
+      if (c12.P != 12) $stop;
+      if (c4.P != 4) $stop;
+      if (c5.P != 5) $stop;
+      if (c12.get_p() != 12) $stop;
+      if (c4.get_p() != 4) $stop;
+      if (c5.get_p() != 5) $stop;
+      if (w16.get_p() != 16) $stop;
+      // verilator lint_off WIDTH
+      c12.member = 32'haaaaaaaa;
+      c4.member = 32'haaaaaaaa;
+      c5.member = 32'haaaaaaaa;
+      // verilator lint_on WIDTH
+      if (c12.member != 12'haaa) $stop;
+      if (c4.member != 4'ha) $stop;
+      if (c12.get_member() != 12'haaa) $stop;
+      if (c4.get_member() != 4'ha) $stop;
+      if ($sformatf("%p", c12) != "'{member:'haaa}") $stop;
+      if ($sformatf("%p", c4) != "'{member:'ha}") $stop;
+
+      $write("*-* All Finished *-*\n");
+      $finish;
+   end
+endmodule