On Thursday, May 8th, 2025 at 7:23 AM, Clem Cole <clemc@ccc.com> wrote:

> Thanks, Noel. I should have pointed to that paper also. I have always considered the demarcation point when structures were added, but I darned if I knew at what date or time Dennis chose to rename it. Clearly, one day (night, more likely), he realized it nb was really not B anymore and needed a new name.
> ᐧ
>
> On Thu, May 8, 2025 at 10:04 AM Noel Chiappa <jnc@mercury.lcs.mit.edu> wrote:
>
> > > From: Clem Cole
> >
> > > The first "C" compiler wa an ephemeral state some time in the process
> > > of its evolution. Dennis started with his B implementation and began to
> > > add features he needed
> >
> > See:
> >
> > The Development of the C Language
> > https://www.nokia.com/bell-labs/about/dennis-m-ritchie/chist.html
> >
> > for detail on the evolution.
> >
> > Noel

For the record another source of old C compiler code would be in
the s1/s2 tapes here:  https://www.tuhs.org/Archive/Distributions/Research/1972_stuff/

I'm not in a place to dig into them right now but one of the two
tapes is a V2 root filesystem backup, the C compiler should be
in a couple stages in /lib.  Granted, its binary, but with
enough disassembly work and comparison with other sources, it
may be possible to recreate a compelling facsimile of whatever
revision that represents.

Otherwise as others have stated, the historic C compiler
situation has been quite well plundered by this and other
groups, supplemented of course by Dennis Ritchie's foresight to
keep and provide so many artifacts and anecdotes.

- Matt G.