diff -r 2de806c8b070 Lib/test/test_strftime.py
--- a/Lib/test/test_strftime.py	Wed Nov 06 22:17:39 2013 +1000
+++ b/Lib/test/test_strftime.py	Wed Nov 06 14:58:58 2013 +0000
@@ -177,5 +177,23 @@
                     print("  Expected %s, but got %s" % (e[1], result))
 
 
+@unittest.skipUnless(sys.platform == "win32", "Only applies to Windows")
+class WindowsTests(unittest.TestCase):
+    """A limitation of the MS C runtime library is that it crashes if
+    a date before 1900 is passed with a format string containing "%y"
+    """
+
+    def test_y_before_1900(self):
+        with self.assertRaises(ValueError):
+            time.strftime("%y", (1899, 1, 1, 0, 0, 0, 0, 0, 0))
+
+    def test_y_1900(self):
+        self.assertEquals(
+            time.strftime("%y", (1900, 1, 1, 0, 0, 0, 0, 0, 0)), "00")
+
+    def test_y_after_1900(self):
+        self.assertEquals(
+            time.strftime("%y", (2013, 1, 1, 0, 0, 0, 0, 0, 0)), "13")
+
 if __name__ == '__main__':
     unittest.main()
diff -r 2de806c8b070 Modules/timemodule.c
--- a/Modules/timemodule.c	Wed Nov 06 22:17:39 2013 +1000
+++ b/Modules/timemodule.c	Wed Nov 06 14:58:58 2013 +0000
@@ -642,6 +642,13 @@
             Py_DECREF(format);
             return NULL;
         }
+        if (strchr("y", outbuf[1]) && buf.tm_year < 0)
+        {
+            PyErr_SetString(PyExc_ValueError,
+                        "format %y requires year >= 1900 on Windows");
+            Py_DECREF(format);
+            return NULL;
+        }
     }
 #endif