Index: Lib/test/regrtest.py
===================================================================
--- Lib/test/regrtest.py	(revision 76260)
+++ Lib/test/regrtest.py	(working copy)
@@ -344,6 +344,10 @@
             print   # Force a newline (just in case)
             print json.dumps(result)
             sys.exit(0)
+        else:
+            print >>sys.stderr, ("No handler for option {}.  Please "
+                "report this as a bug at http://bugs.python.org.").format(o)
+            sys.exit(1)
     if single and fromfile:
         usage(2, "-s and -f don't go together!")
     if use_mp and trace: