1 files changed, 5 insertions, 0 deletions
diff --git a/lib/set.rb b/lib/set.rb
index 009721381b..292a00adf9 100644
--- a/lib/set.rb
+++ b/lib/set.rb
@@ -723,6 +723,11 @@ class SortedSet < Set
             (@keys = @hash.keys).sort! unless @keys
             @keys
           end
+
+          def freeze
+            to_a
+            super
+          end
         END
       end
       module_eval {