1 files changed, 1 insertions, 4 deletions
diff --git a/activesupport/lib/active_support/core_ext/class/attribute.rb b/activesupport/lib/active_support/core_ext/class/attribute.rb
index d2bcd7a778..576366e496 100644
--- a/activesupport/lib/active_support/core_ext/class/attribute.rb
+++ b/activesupport/lib/active_support/core_ext/class/attribute.rb
@@ -61,10 +61,7 @@ class Class
         end
       RUBY
 
-      if instance_writer
-        body = "def #{name}=(value) @#{name} = value end"
-        class_eval body, __FILE__, __LINE__ - 1
-      end
+      attr_writer name if instance_writer
     end
   end
 end