See https://github.com/mpmath/mpmath/issues/1013. Probably it's PyPy issue, gmpy backend (gmpy2) is also affected. Edit: Upstream bug (maybe): https://github.com/pypy/pypy/issues/4946
See mpmath/mpmath#1013. Probably it's PyPy issue, gmpy backend (gmpy2) is also affected.
Edit:
Upstream bug (maybe): pypy/pypy#4946