diff -r 37c7f9fb7040 -r a9ccd9af48ef mercurial/transaction.py
--- a/mercurial/transaction.py	Mon Jun 13 05:11:56 2016 +0900
+++ b/mercurial/transaction.py	Mon Jun 13 05:11:56 2016 +0900
@@ -72,7 +72,7 @@
                 filepath = vfs.join(f)
                 backuppath = vfs.join(b)
                 try:
-                    util.copyfile(backuppath, filepath)
+                    util.copyfile(backuppath, filepath, checkambig=True)
                     backupfiles.append(b)
                 except IOError:
                     report(_("failed to recover %s\n") % f)