compare modifyed workspace with Head SVN revison

Hi.
After build, I need to check what changes build made comparing with last revision.
As i understood, plugin retrieve revision from workspace and then compare it with specified revision?
Or it compare workspace with specified revision, and I use it wrong?

Why I need it.
Before I deploy release to production, I need to check if was made some hot fixes directly on production without committing them in SVN.
What I think to do.
I will download that changes using RSync to Jenkins workspace and check modification with Last Changes Plugin. If all is OK I will deploy release to production.