1 files changed, 12 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/core_ext/object/duplicable.rb b/activesupport/lib/active_support/core_ext/object/duplicable.rb
index 9d044eba71..6c607b0d16 100644
--- a/activesupport/lib/active_support/core_ext/object/duplicable.rb
+++ b/activesupport/lib/active_support/core_ext/object/duplicable.rb
@@ -104,3 +104,15 @@ class Module
     false
   end
 end
+
+class BigDecimal
+  begin
+    BigDecimal.new('4.56').dup
+
+    def duplicable?
+      true
+    end
+  rescue TypeError
+    # can't dup, so use superclass implementation
+  end
+end