@@ -155,6 +155,7 @@ private static StolenReference FromSpec(TypeSpec spec, PyTuple? bases = null)
             using var nativeSpec = new NativeTypeSpec(spec);
             var basesRef = bases is null ? default : bases.Reference;
             var result = Runtime.PyType_FromSpecWithBases(in nativeSpec, basesRef);
+            // Runtime.PyErr_Print();
             return result.StealOrThrow();
         }
     }
 
@@ -475,17 +475,20 @@ internal static PyType CreateMetatypeWithGCHandleOffset()
             int size = Util.ReadInt32(Runtime.PyTypeType, TypeOffset.tp_basicsize)
                        + IntPtr.Size // tp_clr_inst_offset
             ;
-            var result = new PyType(new TypeSpec("clr._internal.GCOffsetBase", basicSize: size,
-                new TypeSpec.Slot[]
-                {
-
-                },
-                TypeFlags.Default | TypeFlags.HeapType | TypeFlags.HaveGC),
-                bases: new PyTuple(new[] { py_type }));
 
-            SetRequiredSlots(result, seen: new HashSet<string>());
-
-            Runtime.PyType_Modified(result);
+            var slots = new[] {
+                new TypeSpec.Slot(TypeSlotID.tp_traverse, subtype_traverse),
+                new TypeSpec.Slot(TypeSlotID.tp_clear, subtype_clear)
+            };
+            var result = new PyType(
+                new TypeSpec(
+                    "clr._internal.GCOffsetBase",
+                    basicSize: size,
+                    slots: slots,
+                    TypeFlags.Default | TypeFlags.HeapType | TypeFlags.HaveGC
+                ),
+                bases: new PyTuple(new[] { py_type })
+            );
 
             return result;
         }
Original file line number	Diff line number	Diff line change
@@ -155,6 +155,7 @@ private static StolenReference FromSpec(TypeSpec spec, PyTuple? bases = null)
155	155	using var nativeSpec = new NativeTypeSpec(spec);
156	156	var basesRef = bases is null ? default : bases.Reference;
157	157	var result = Runtime.PyType_FromSpecWithBases(in nativeSpec, basesRef);
	158	+ // Runtime.PyErr_Print();
158	159	return result.StealOrThrow();
159	160	}
160	161	}