diff -r 5f0465d0e91e Lib/test/test_xrange.py
--- a/Lib/test/test_xrange.py	Tue Sep 25 02:48:21 2012 -0700
+++ b/Lib/test/test_xrange.py	Tue Sep 25 14:10:46 2012 +0100
@@ -46,6 +46,31 @@
                 self.fail('{}: wrong element at position {};'
                           'expected {}, got {}'.format(test_id, i, y, x))
 
+    def assert_xranges_equivalent(self, x, y):
+        # Check that two xrange objects are equivalent, in the sense of the
+        # associated sequences being the same.  We want to use this for large
+        # xrange objects, so instead of converting to lists and comparing
+        # directly we do a number of indirect checks.
+        if len(x) != len(y):
+            self.fail('{} and {} have different '
+                      'lengths: {} and {} '.format(x, y, len(x), len(y)))
+        # Provided that there's at least one element,
+        # check first and last elements match.
+        if len(x) >= 1:
+            if x[0] != y[0]:
+                self.fail('{} and {} have different initial '
+                          'elements: {} and {} '.format(x, y, x[0], y[0]))
+            if x[-1] != y[-1]:
+                self.fail('{} and {} have different final '
+                          'elements: {} and {} '.format(x, y, x[-1], y[-1]))
+        # If there are at least two elements, check the step.
+        if len(x) >= 2:
+            x_step = x[1] - x[0]
+            y_step = y[1] - y[0]
+            if x_step != y_step:
+                self.fail('{} and {} have different step: '
+                          '{} and {} '.format(x, y, x_step, y_step))
+
     def test_xrange(self):
         self.assertEqual(list(xrange(3)), [0, 1, 2])
         self.assertEqual(list(xrange(1, 5)), [1, 2, 3, 4])
@@ -104,6 +129,60 @@
                 self.assertEqual(list(pickle.loads(pickle.dumps(r, proto))),
                                  list(r))
 
+        M = min(sys.maxint, sys.maxsize)
+        large_testcases = testcases + [
+            (0, M, 1),
+            (M, 0, -1),
+            (0, M, M - 1),
+            (M // 2, M, 1),
+            (0, -M, -1),
+            (0, -M, 1 - M),
+            (-M, M, 2),
+            (-M, M, 1024),
+            (-M, M, 10585),
+            (M, -M, -2),
+            (M, -M, -1024),
+            (M, -M, -10585),
+            ]
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            for t in large_testcases:
+                r = xrange(*t)
+                r_out = pickle.loads(pickle.dumps(r, proto))
+                self.assert_xranges_equivalent(r_out, r)
+
+    def test_repr(self):
+        # Check that repr of an xrange is a valid representation
+        # of that xrange.
+
+        # Valid xranges have at most min(sys.maxint, sys.maxsize) elements.
+        M = min(sys.maxint, sys.maxsize)
+
+        testcases = [
+            (13,),
+            (0, 11),
+            (-22, 10),
+            (20, 3, -1),
+            (13, 21, 3),
+            (-2, 2, 2),
+            (0, M, 1),
+            (M, 0, -1),
+            (0, M, M - 1),
+            (M // 2, M, 1),
+            (0, -M, -1),
+            (0, -M, 1 - M),
+            (-M, M, 2),
+            (-M, M, 1024),
+            (-M, M, 10585),
+            (M, -M, -2),
+            (M, -M, -1024),
+            (M, -M, -10585),
+            ]
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            for t in testcases:
+                r = xrange(*t)
+                r_out = eval(repr(r))
+                self.assert_xranges_equivalent(r, r_out)
+
     def test_range_iterators(self):
         # see issue 7298
         limits = [base + jiggle
diff -r 5f0465d0e91e Objects/rangeobject.c
--- a/Objects/rangeobject.c	Tue Sep 25 02:48:21 2012 -0700
+++ b/Objects/rangeobject.c	Tue Sep 25 14:10:46 2012 +0100
@@ -105,6 +105,29 @@
     return (Py_ssize_t)(r->len);
 }
 
+/* Stop value suitable for use in repr and reduce.
+ *
+ * Computes start + len * step, clipped to the range [LONG_MIN, LONG_MAX].
+ */
+static long
+range_stop(rangeobject *r)
+{
+    long last;
+
+    if (r->len == 0)
+        return r->start;
+
+    /* The tricky bit is avoiding overflow.  Here we first compute the last
+       entry in the xrange (start + (len - 1) * step), which is guaranteed to
+       lie within the range of a long, and then add step to it. */
+    last = (long)(r->start + (unsigned long)(r->len - 1) * r->step);
+    if (r->step > 0)
+        return last > LONG_MAX - r->step ? LONG_MAX : last + r->step;
+    else
+        return last < LONG_MIN - r->step ? LONG_MIN : last + r->step;
+}
+
+
 static PyObject *
 range_repr(rangeobject *r)
 {
@@ -112,17 +135,17 @@
 
     if (r->start == 0 && r->step == 1)
         rtn = PyString_FromFormat("xrange(%ld)",
-                                  r->start + r->len * r->step);
+                                  range_stop(r));
 
     else if (r->step == 1)
         rtn = PyString_FromFormat("xrange(%ld, %ld)",
                                   r->start,
-                                  r->start + r->len * r->step);
+                                  range_stop(r));
 
     else
         rtn = PyString_FromFormat("xrange(%ld, %ld, %ld)",
                                   r->start,
-                                  r->start + r->len * r->step,
+                                  range_stop(r),
                                   r->step);
     return rtn;
 }
@@ -131,9 +154,9 @@
 static PyObject *
 range_reduce(rangeobject *r, PyObject *args)
 {
-    return Py_BuildValue("(O(iii))", Py_TYPE(r),
+    return Py_BuildValue("(O(lll))", Py_TYPE(r),
                          r->start,
-                         r->start + r->len * r->step,
+                         range_stop(r),
                          r->step);
 }