Incorrect conversion of Python object to R, possibly due to integer overflow

[TengMCing]

Hi reticulate developers,

I ran into a weird issue using reticulate: when I compute the sum of squares of a sequence of large numbers and convert it back into R, it seems like an integer overflow occurs. There’s no warning and no automatic conversion to double, which can be confusing. It would be helpful if either a warning was shown or the data was automatically converted to double.

library(reticulate)
py_run_string('def cum_square(n): return sum([x**2 for x in range(n + 1)])')
py$cum_square(10000L)
#> [1] -1624114088

^{Created on 2025-09-10 with reprex v2.1.1}

Session info

sessioninfo::session_info()
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#>  date     2025-09-10
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#> ──────────────────────────────────────────────────────────────────────────────