diff -r 7e9ccb1670e3 -r da13616d1a92 mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Thu Aug 31 18:35:39 2017 -0700
+++ b/mercurial/cmdutil.py	Fri Sep 01 12:34:36 2017 -0700
@@ -3039,7 +3039,6 @@
     ui.note(_('amending changeset %s\n') % old)
     base = old.p1()
 
-    newid = None
     with repo.wlock(), repo.lock(), repo.transaction('amend'):
         # See if we got a message from -m or -l, if not, open the editor
         # with the message of the changeset to amend
@@ -3164,6 +3163,7 @@
             return old.node()
 
         ph = repo.ui.config('phases', 'new-commit', phases.draft)
+        newid = None
         try:
             if opts.get('secret'):
                 commitphase = 'secret'