There's some question about the correctness of the hash function, but
if it's wrong, the 32-bit version is also wrong.

Amul Sul, reviewed by Hironobu Suzuki

Discussion: https://postgr.es/m/CAAJ_b947JjnNr9Cp45iNjSqKf6PA5mCTmKsRwPjows93YwQrmw@mail.gmail.com