[TUHS] "Notes on the IBM C Compiler" by Mike Lesk

[John R Levine via TUHS]

On Sun, 12 Jul 2026, Clem Cole wrote:
> BLISS was CMU's system programming language, designed by Bill Wulf and his
> students in the late 1960s/early 1970s. The original compiler was a PDP-10
> target (the urban legend is that it was bootstrapped using TECO macros, but
> I don't believe that).  BLISS-11 followed a few years later; it was a
> cross-compiler that ran on TOPS-10 (it could not self-host).  Compared to
> Dennis's C compiler, a contemporary development, the code it generates makes
> the UNIX C compiler seem almost like a toy (although C could self-host,
> unlike BLISS-11).

We used PDP-10 BLISS a lot when I was a grad student at Yale in the 1970s. 
We were aware of BLISS-11 but didn't use it, first because Ned Irons was 
working on his extensible IMP-72, and in 1976 I installed Unix on our 
PDP-11 and that's what we used.  BLISS was a strange language due to 
everything being an expression and no implicit dereferencing (A=B would 
put the address of B into A, A = .B gets the contents of B) but once you 
got used to it, it was a very usable language.

BLISS-11 did excellent optimization but it's my impression that on a 
PDP-11 if you wrote C code with reasonable register declarations, the code 
wasn't much worse even though the compiler was much less clever.

> The CMU BLISS compiler is discussed in
> the "Green Book," and after that experiment, quickly became the "how-to
> manual" for compiler code generation/optimization:

Yes, I have a copy.  A few decades back I talked to Wulf about putting it 
back in print but we found it was available from a print-on-demand 
publisher, I think one that usually handled PhD theses.  These days you 
can download it:

https://archive.org/details/wulf-the-design-of-an-optimizing-compiler-1975

> As for the IBM 360 family, at some point, one of Gary Kildall's (of CP/M
> fame - remember he was a compiler researcher, not an OS one) students at
> the Naval Postgraduate School wrote a 360 ISA target; but I don't remember
> the OS target for the original 360 compiler.  ....

Someone who knows the details should add that to the Wikipedia article on 
BLISS.

R's,
John