diff -r b541ecd32115 Doc/library/itertools.rst
--- a/Doc/library/itertools.rst	Fri Feb 07 16:11:17 2014 -0800
+++ b/Doc/library/itertools.rst	Sat Feb 08 18:09:48 2014 +0800
@@ -524,25 +524,34 @@
 
 .. function:: repeat(object[, times])
 
-   Make an iterator that returns *object* over and over again. Runs indefinitely
-   unless the *times* argument is specified. Used as argument to :func:`map` for
-   invariant parameters to the called function.  Also used with :func:`zip` to
-   create an invariant part of a tuple record.  Equivalent to::
+    Return an iterator which yields the object for the specified number of
+    times.  If times is unspecified, yields the object forever.  If times is
+    negative, behave as if times is 0.
 
-      def repeat(object, times=None):
-          # repeat(10, 3) --> 10 10 10
-          if times is None:
-              while True:
-                  yield object
-          else:
-              for i in range(times):
-                  yield object
+    Equivalent to::
 
-   A common use for *repeat* is to supply a stream of constant values to *map*
-   or *zip*::
+        def repeat(object, times=None):
+            # repeat(10, 3) --> 10 10 10
+            if times is None:
+                while True:
+                    yield object
+            else:
+                for i in range(times):
+                    yield object
 
-      >>> list(map(pow, range(10), repeat(2)))
-      [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
+    A common use for repeat is to supply a stream of constant values to map or
+    zip:
+
+        >>> list(map(pow, range(10), repeat(2)))
+        [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
+
+    .. note::
+
+       If "times" is specified using a keyword argument, and provided with a
+       negative value, repeat yields the object forever.  This is a bug, its
+       use is unsupported, and this behavior may be removed in a future version
+       of Python.
+
 
 .. function:: starmap(function, iterable)
 
diff -r b541ecd32115 Lib/test/test_itertools.py
--- a/Lib/test/test_itertools.py	Fri Feb 07 16:11:17 2014 -0800
+++ b/Lib/test/test_itertools.py	Sat Feb 08 18:09:48 2014 +0800
@@ -960,6 +960,10 @@
         list(r)
         self.assertEqual(repr(r), 'repeat((1+0j), 0)')
 
+        # Test negative value times sent via keyword (issue #19145).
+        self.assertEqual(repr(repeat(1, times=-1)), 'repeat(1)')
+        self.assertEqual(repr(repeat(1, times=-2)), 'repeat(1, -2)')
+
         # check copy, deepcopy, pickle
         c = repeat(object='a', times=10)
         self.assertEqual(next(c), 'a')
diff -r b541ecd32115 Modules/itertoolsmodule.c
--- a/Modules/itertoolsmodule.c	Fri Feb 07 16:11:17 2014 -0800
+++ b/Modules/itertoolsmodule.c	Sat Feb 08 18:09:48 2014 +0800
@@ -4097,6 +4097,10 @@
                                      &element, &cnt))
         return NULL;
 
+    /* There is a leak here. If negative value sent to times via keyword, the
+     * cnt will be negative. It should be 0. This bug is preserved because of
+     * backward compatibility concern (issue #19145).
+     */
     if (PyTuple_Size(args) == 2 && cnt < 0)
         cnt = 0;
 
@@ -4175,9 +4179,10 @@
 };
 
 PyDoc_STRVAR(repeat_doc,
-"repeat(object [,times]) -> create an iterator which returns the object\n\
-for the specified number of times.  If not specified, returns the object\n\
-endlessly.");
+"repeat(object [,times]) -> iterator\n\n\
+Return an iterator which yields the object for the specified number of times.\n\
+If times is unspecified, yields the object forever.  If times is negative,\n\
+behave as if times is 0.");
 
 static PyTypeObject repeat_type = {
     PyVarObject_HEAD_INIT(NULL, 0)