Complex Arithmetic Bug: Exponentiation

[aerusso]

The following cython file should emit -1/32 twice (up to a zero imaginary component). My machine produces a nan+nanj for the second.

print((-0.5)**5,(-0.5+0j)**5)

This is present in the Debian packaging of Cython3 0.25.2. I have not tested mainline cython3.

[robertwb]

Thanks for finding this.