--- a/mercurial/exchange.py	Tue Sep 12 15:12:27 2017 -0700
+++ b/mercurial/exchange.py	Tue Sep 12 09:13:02 2017 -0700
@@ -1632,8 +1632,9 @@
                 raise ValueError(_('no common changegroup version'))
             version = max(cgversions)
         outgoing = _computeoutgoing(repo, heads, common)
-        cgstream = changegroup.makestream(repo, outgoing, version, source,
-                                          bundlecaps=bundlecaps)
+        if outgoing.missing:
+            cgstream = changegroup.makestream(repo, outgoing, version, source,
+                                              bundlecaps=bundlecaps)
 
     if cgstream:
         part = bundler.newpart('changegroup', data=cgstream)