Fixing weird COMPLR bug fixes SI:INVALIDATED loss too?

[Jon L White <JONL at MIT-MC>]

    Date: 20 November 1981 00:13-EST
    From: Alan Bawden <ALAN at MIT-MC>
    I reported a bug several months back and left a test case in
    ALAN;LOSS >. . . 
    (This is the (foo x <hairy-expression>) bug again, remember?)
This bug is now fixed in COMPLR 1130.  It resulted from a bad
interaction between "optimizing" COND compilations and PROGN
compilations, and only occured in quite contorted situations.

This problem is probalby responsible for the lossage noted by WGD 
and EB previously when some displaced macro got munged; since the 
munging was not due to any bug in DEFMAX, it would have to be some 
bug like this one (or, horrors, a GC bug).  Probaly EB and WGD should 
recompile their macro files, and report any future SI:INVALIDATED 
comments to bug-complr too.  (The SI:INVALIDATED note ocurs when
displaced macro call gets randomly RPLAC'd, which could certainly
happen when "foo" in alan's example is the call to DISPLACE for
macro displacement).