diff -r abb5ec3eb6ce -r ef1eb6df7071 mercurial/simplemerge.py
--- a/mercurial/simplemerge.py	Sun Oct 11 15:04:00 2015 -0700
+++ b/mercurial/simplemerge.py	Fri Oct 09 13:54:52 2015 -0700
@@ -414,6 +414,4 @@
         out.close()
 
     if m3.conflicts and not mode == 'union':
-        if not opts.get('quiet'):
-            ui.warn(_("warning: conflicts during merge.\n"))
         return 1