BUG: Sum on large integers incorrect after rolling timewindow

[snthibaud]

• I have checked that this issue has not already been reported.

• I have confirmed this bug exists on the latest version of pandas.

• (optional) I have confirmed this bug exists on the master branch of pandas.

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Code Sample, a copy-pastable example

import pandas as pd
from datetime import datetime, timedelta

s1 = pd.Series([138, 2377900603251717750], index=pd.Index([datetime(year=1970, month=1, day=1), datetime(year=1970, month=1, day=1)+timedelta(microseconds=1)]))
s2 = s1.rolling("1D").sum()
print(s2.sum() >= s1.sum())

Problem description

The sum of the rolling window should be higher or equal to the original series because only positive values are in it. However, 'False' is printed.

Expected Output

True

Output of pd.show_versions()

INSTALLED VERSIONS ------------------ commit : 7d32926 python : 3.7.10.final.0 python-bits : 64 OS : Darwin OS-release : 20.3.0 Version : Darwin Kernel Version 20.3.0: Thu Jan 21 00:07:06 PST 2021; root:xnu-7195.81.3~1/RELEASE_X86_64 machine : x86_64 processor : i386 byteorder : little LC_ALL : None LANG : None LOCALE : None.UTF-8 pandas : 1.2.2 numpy : 1.19.4 pytz : 2020.1 dateutil : 2.8.1 pip : 21.0.1 setuptools : 49.6.0.post20210108 Cython : None pytest : 6.2.2 hypothesis : 6.3.1 sphinx : None blosc : None feather : None xlsxwriter : None lxml.etree : 4.5.2 html5lib : None pymysql : 1.0.2 psycopg2 : None jinja2 : 2.11.2 IPython : 7.20.0 pandas_datareader: None bs4 : 4.7.1 bottleneck : None fsspec : None fastparquet : None gcsfs : None matplotlib : 3.2.2 numexpr : None odfpy : None openpyxl : 3.0.6 pandas_gbq : None pyarrow : 3.0.0 pyxlsb : None s3fs : None scipy : 1.6.0 sqlalchemy : 1.3.23 tables : None tabulate : None xarray : None xlrd : None xlwt : None numba : None

[phofl]

This is probably because this is internally cast to float, because the cython implementation expects floats.

This is probably a duplicate of #11446

[phofl]

closing as duplicate