Merged revisions 69433,69436 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r69433 | mark.dickinson | 2009-02-08 13:58:10 +0000 (Sun, 08 Feb 2009) | 2 lines

  Remove redundant assignment in _PyObject_LengthHint
........
  r69436 | mark.dickinson | 2009-02-08 14:42:28 +0000 (Sun, 08 Feb 2009) | 10 lines

  Issue #789290: make sure that hash(2**63) == hash(2.**63) on 64-bit
  platforms.  The previous code was fragile, depending on the twin
  accidents that:

    (1) in C, casting the double value 2.**63 to long returns the integer
        value -2**63, and
    (2) in Python, hash(-2**63) == hash(2**63).

  There's already a test for this in test_hash.
........

Objects/abstract.c

@@ -123,7 +123,7 @@ _PyObject_LengthHint(PyObject *o, Py_ssize_t defaultvalue)
 		PyErr_Clear();
 		return defaultvalue;
 	}
-	rv = rv = PyLong_Check(ro) ? PyLong_AsSsize_t(ro) : defaultvalue;
+	rv = PyLong_Check(ro) ? PyLong_AsSsize_t(ro) : defaultvalue;
 	Py_DECREF(ro);
 	return rv;
 }

Objects/object.c

@@ -1023,7 +1023,7 @@ _Py_HashDouble(double v)
 	fractpart = modf(v, &intpart);
 	if (fractpart == 0.0) {
 		/* This must return the same hash as an equal int or long. */
-		if (intpart > LONG_MAX || -intpart > LONG_MAX) {
+		if (intpart > LONG_MAX/2 || -intpart > LONG_MAX/2) {
 			/* Convert to long and use its hash. */
 			PyObject *plong;	/* converted to Python long */
 			if (Py_IS_INFINITY(intpart))