--- a/Doc/using/cmdline.rst	Fri Jan 20 11:23:02 2012 +0000
+++ b/Doc/using/cmdline.rst	Mon Jan 30 12:29:09 2012 -0500
@@ -21,7 +21,7 @@
 
 When invoking Python, you may specify any of these options::
 
-    python [-bBdEhiOsSuvVWx?] [-c command | -m module-name | script | - ] [args]
+    python [-bBdEhiORsSuvVWx?] [-c command | -m module-name | script | - ] [args]
 
 The most common use case is, of course, a simple invocation of a script::
 
@@ -215,6 +215,30 @@
    Discard docstrings in addition to the :option:`-O` optimizations.
 
 
+.. cmdoption:: -R
+
+   Turn on "hash randomization, so that the :meth:`__hash__` values of str,
+   bytes and datetime objects are "salted" with an unpredictable random value.
+   Although they remain constant within an individual Python process, they
+   are not predictable between repeated invocations of Python.
+
+   This is intended to provide protection against a denial-of-service
+   caused by carefully-chosen inputs that exploit the worst case performance
+   of a dict lookup, O(n^2) complexity.  See:
+
+       http://www.ocert.org/advisories/ocert-2011-003.html
+
+   for details.
+
+   Changing hash values affects the order in which keys are retrieved from
+   a dict.  Although Python has never made guarantees about this ordering
+   (and it typically varies between 32-bit and 64-bit builds), enough
+   real-world code implicitly relies on this non-guaranteed behavior that
+   the randomization is disabled by default.
+
+   See also :envvar:`PYTHONHASHRANDOMIZATION`.
+
+
 .. cmdoption:: -s
 
    Don't add user site directory to sys.path
@@ -435,6 +459,24 @@
    import of source modules.
 
 
+.. envvar:: PYTHONHASHRANDOMIZATION
+
+   If this is set to a non-empty string it is equivalent to specifying the
+   :option:`-R` option.
+
+
+.. envvar:: PYTHONHASHSEED
+
+   If this is set, it is used as a fixed seed for generating the hash() of
+   the types covered by the :option:`-R` option (or its equivalent,
+   :envvar:`PYTHONHASHRANDOMIZATION`.
+
+   Its purpose is for use in selftests for the interpreter.
+
+   It should be a decimal number in the range [0; 4294967295].  Specifying
+   the value 0 overrides the other setting, disabling the hash random salt.
+
+
 .. envvar:: PYTHONIOENCODING
 
    Overrides the encoding used for stdin/stdout/stderr, in the syntax