Bug in 78.23

[Gerald R. Barber <JerryB at MIT-AI>]

In System 78.22, ZMail 38.4, microcode 841, 60Hz, on Lisp Machine Four:

Patch 78.23 is introducing a bug into the flavor system that manifests
itself as an infinite loop within GETHASH-EQUAL which is called from
SI:FLAVOR-METHOD-ENTRY. 

To reproduce this load 78.23 and then do (LOAD "AI:ECC;XMEGA LOAD").
Part way through the loading of OMEGA;MMES (which is about the 10th file
loaded) the machine will go into a loop within GETHASH-EQUAL.

This happens in microcode 836 as well as this one.