1 files changed, 11 insertions, 0 deletions

diff --git a/lisp/vc-svn.el b/lisp/vc-svn.el
index ddecb89d77c..0b34c30f630 100644
--- a/lisp/vc-svn.el
+++ b/lisp/vc-svn.el
@@ -399,6 +399,17 @@ The changes are between FIRST-VERSION and SECOND-VERSION."
 
 (defun vc-svn-diff (files &optional oldvers newvers buffer)
   "Get a difference report using SVN between two versions of fileset FILES."
+  (and oldvers
+       (catch 'no
+         (dolist (f files)
+           (or (equal oldvers (vc-workfile-version f))
+               (throw 'no nil)))
+         t)
+       ;; Use nil rather than the current revision because svn handles
+       ;; it better (i.e. locally).  Note that if _any_ of the files
+       ;; has a different revision, we fetch the lot, which is
+       ;; obviously sub-optimal.
+       (setq oldvers nil))
   (let* ((switches
             (if vc-svn-diff-switches
                 (vc-switches 'SVN 'diff)