Dan Cross: I seem to recall that LCC was also used, at least on 10th Ed. Am I imagining things, or was that real? === Some of the earliest work on lcc was done in 1127; Chris Fraser worked for the Labs for some years, Dave Hanson collaborated from his appointment at Princeton. I believe there was a /usr/bin/lcc. Some programs used it, either because they needed some part of the ISO syntax (pcc2 was pre-ISO) or just because. I don't think that version of lcc used Reiser's c2 optimizer; it generated reasonably good code by itself, including emitting auto-increment/decrement instructions. Later versions of lcc (such as that I later adopted as cc in my personal V10 world) couldn't do that any more, so I had to keep c2, and in fact to modify it to turn addl3 a,b,(p) mova 4(p),p into addl3 a,b,(p)+ (or maybe it was addl2 $4,p, I forget) But that's another story which I'll tell only if asked, and nothing to do with the original question.