Index: src/runtime/class.m
==================================================================
--- src/runtime/class.m
+++ src/runtime/class.m
@@ -542,11 +542,13 @@
 	if (rcls->subclass_list != NULL) {
 		free(rcls->subclass_list);
 		rcls->subclass_list = NULL;
 	}
 
-	objc_sparsearray_free(rcls->dtable);
+	if (rcls->dtable != NULL)
+		objc_sparsearray_free(rcls->dtable);
+
 	rcls->dtable = NULL;
 
 	if (rcls->superclass != Nil)
 		cls->superclass = rcls->superclass->name;
 }