[Info-vax] Poulson info from Dave Cantor

[Michael Kraemer]

In article <ic3qtf$9af$1 at news.eternal-september.org>, glen herrmannsfeldt
<gah at ugcs.caltech.edu> writes:
.
> 
> That tends to be a problem with RISC, and even worse with VLIW.

not necessarily. 
I just tried an ancient "edt" built in 1991 for POWER1,
still runs on POWER7, unmodified.
 
> Note that IBM's z/OS running on z/Architecture machines currently
> in production will run object and executables written over 40 years
> ago for OS/360 on S/360 hardware.  There are incompatible changes
> in privileged instructions, but problem state code runs just fine. 

well, we don't know whether POWER will still be around in another 20 years,
but if so, chances are not negligible that the "edt" binary will still run.