1 files changed, 2 insertions, 2 deletions
diff --git a/actionpack/lib/action_controller/vendor/rack-1.0/rack/deflater.rb b/actionpack/lib/action_controller/vendor/rack-1.0/rack/deflater.rb
index 3e66680092..a42b7477ae 100644
--- a/actionpack/lib/action_controller/vendor/rack-1.0/rack/deflater.rb
+++ b/actionpack/lib/action_controller/vendor/rack-1.0/rack/deflater.rb
@@ -36,12 +36,12 @@ module Rack
         mtime = headers.key?("Last-Modified") ?
           Time.httpdate(headers["Last-Modified"]) : Time.now
         body = self.class.gzip(body, mtime)
-        size = body.respond_to?(:bytesize) ? body.bytesize : body.size
+        size = Rack::Utils.bytesize(body)
         headers = headers.merge("Content-Encoding" => "gzip", "Content-Length" => size.to_s)
         [status, headers, [body]]
       when "deflate"
         body = self.class.deflate(body)
-        size = body.respond_to?(:bytesize) ? body.bytesize : body.size
+        size = Rack::Utils.bytesize(body)
         headers = headers.merge("Content-Encoding" => "deflate", "Content-Length" => size.to_s)
         [status, headers, [body]]
       when "identity"