ref: 313cf4107eb9ebb2e2b7b6c8f61b93eac0b19a11
parent: c9ff32c97711bc0a0150d3cc03e79aad3c80e381
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Sat Aug 20 23:20:35 EDT 2016
libmp: mptrunc: normalize after mpassign to handle the case b==r (from 9front)