diff -r 874712506b07 -r c31ce080eb75 hgext/infinitepush/__init__.py
--- a/hgext/infinitepush/__init__.py	Fri Sep 21 21:14:27 2018 -0400
+++ b/hgext/infinitepush/__init__.py	Sun Sep 23 00:47:04 2018 -0400
@@ -1182,5 +1182,6 @@
         cmdline = [util.hgexecutable(), 'debugfillinfinitepushmetadata',
                    '-R', root] + nodesargs
         # Process will run in background. We don't care about the return code
-        subprocess.Popen(cmdline, close_fds=True, shell=False,
+        subprocess.Popen(pycompat.rapply(procutil.tonativestr, cmdline),
+                         close_fds=True, shell=False,
                          stdin=devnull, stdout=devnull, stderr=devnull)