diff -Nrup a/job.c b/job.c

--- a/job.c	2016-05-21 16:22:32.000000000 -0400

+++ b/job.c	2017-06-11 09:37:31.964954015 -0400

@@ -2561,7 +2561,11 @@ construct_command_argv_internal (char *l

   /* See if it is safe to parse commands internally.  */

   if (shell == 0)

-    shell = default_shell;

+    {

+      shell = default_shell;

+      if (shellflags == 0)

+	shellflags = "-c";

+    }

 #ifdef WINDOWS32

   else if (strcmp (shell, default_shell))

   {