TestDatetimeIndex.test_reindex_with_same_tz 32-bit CI failing in MacPython

[TomAugspurger]

https://dev.azure.com/pandas-dev/pandas-wheels/_build/results?buildId=34375&view=logs&j=517fe804-fa30-5dc2-1413-330699242c05&t=2e128ad5-2f7f-5333-3f34-c85b8fbc7250&l=1267

=================================== FAILURES ===================================
_________________ TestDatetimeIndex.test_reindex_with_same_tz __________________
[gw1] linux -- Python 3.7.0 /venv/bin/python

        rng_a = date_range("2010-01-01", "2010-01-02", periods=24, tz="utc")
        rng_b = date_range("2010-01-01", "2010-01-02", periods=23, tz="utc")
        result1, result2 = rng_a.reindex(
            rng_b, method="nearest", tolerance=timedelta(seconds=20)
        )
        expected_list1 = [
            "2010-01-01 00:00:00",
            "2010-01-01 01:05:27.272727272",
            "2010-01-01 02:10:54.545454545",
            "2010-01-01 03:16:21.818181818",
            "2010-01-01 04:21:49.090909090",
            "2010-01-01 05:27:16.363636363",
            "2010-01-01 06:32:43.636363636",
            "2010-01-01 07:38:10.909090909",
            "2010-01-01 08:43:38.181818181",
            "2010-01-01 09:49:05.454545454",
            "2010-01-01 10:54:32.727272727",
            "2010-01-01 12:00:00",
            "2010-01-01 13:05:27.272727272",
            "2010-01-01 14:10:54.545454545",
            "2010-01-01 15:16:21.818181818",
            "2010-01-01 16:21:49.090909090",
            "2010-01-01 17:27:16.363636363",
            "2010-01-01 18:32:43.636363636",
            "2010-01-01 19:38:10.909090909",
            "2010-01-01 20:43:38.181818181",
            "2010-01-01 21:49:05.454545454",
            "2010-01-01 22:54:32.727272727",
            "2010-01-02 00:00:00",
        ]
        expected1 = DatetimeIndex(
            expected_list1, dtype="datetime64[ns, UTC]", freq=None,
        )
        expected2 = np.array([0] + [-1] * 21 + [23], dtype=np.int64,)
        tm.assert_index_equal(result1, expected1)
>       tm.assert_numpy_array_equal(result2, expected2)
E       AssertionError: numpy array are different
E       
E       Attribute "dtype" are different
E       [left]:  int32
E       [right]: int64

[TomAugspurger]

Git blame maybe points to #33265. cc @BenjaminLiuPenrose.

@jreback do you know what the expected dtype of the indexer return value from Index.reindex is? Is it the platform int? If so, maybe just need to change that np.int64 to np.dtype('int').