[TUHS] History of non-Bell C compilers?

[Phil Budne]

On Thu, 7 Mar 2024 Larry McVoy wrote:
> My memory is BDS C did C just fine, but had a very non standard standard
> I/O library.  I had relearn stdio when I got to Unix.  But I never had a
> problem with it not compiling C.

Early on (originally?) a question asked was "what non-AT&T origin
compilers were used to compile Unix.  Two non-AT&T compilers I
remember wrangling with on U in the 1980's were Green Hills (on the
Encore Multimax), and another compiler on some early flavor of ROMP or
Power based IBM workstation.  Maybe it was xlc?

I remember one of them was unaware that case labels are valid ANYWHERE
inside of a switch statement (the feature Duff applied so cleverly),
something I discovered trying to bring up cfront (the original
C++/C-with-classes compiler, that output C).

On BDS C, I remember chatting with Leor Zolman: he was looking to
contract someone to port BDS (Brain Damage Systems) C to the PC, but
it was written in assembly language, so it wasn't a particularly
attractive job.  I don't recall him having a _particularly_ high
opinion of the code, but I could be misremembering.