I’m further looking into BCPL / B / C family compilers on 16-bit mini-computers prior to 1979.

Lot’s of interesting stuff. BCPL was extended with structures at least twice and plenty struggle with (un)scaled pointers. It seems that the Nova was a much easier target than the PDP-11, with a simpler code generator sufficing to generate quality code. I’ll report more fully when I’m further along with my review.

On May 8, 2024, at 5:51 PM, Clem Cole <clemc@ccc.com> wrote:

IIRC, Mike Malcom and the team built a true B compiler so they could develop Thoth.   As the 11/40 was one of the original Thoth target systems,  I would have expected that to exist, but I have never used it.

Yes, they did. I’m working through the various papers on Thoth and the Eh / Zed compilers (essentially B with tweaks). I’ve requested pdf’s of two theses that are only on micro-fiche from the Uni of Waterloo library, hopefully this is possible. The original target machines were Honeywell 6060, DG Nova, Microdata 1600/30 and TI-990. The latter is close enough to a PDP-11. This compiler is from 1976.

I’ve browsed around for surviving Thoth source code, but it would seem to be lost. Does anyone know of surviving Thoth bits?