And speaking of ALGOL

Paul Koning paulkoning at
Tue Aug 11 09:52:12 CDT 2015

> On Aug 11, 2015, at 1:16 AM, Chuck Guzis <cclist at> wrote:
> On 08/10/2015 07:07 PM, Mark Kahrs wrote:
>> One could always implement a KDF9 emulator and then port Randall and
>> Russell code (from the book).
>> And r.e. ALGOL68, Peter Hibbard had some sort of ALGOL68 system
>> working on the PDP11s at CMU I believe.
> Why all this DEC stuff about Algol?  Go to the source--the Burroughs B5500 (or if you want, the B5000).  A piece of engineering much advanced for its time.

Yes, that was a pretty nice system.  Certainly not the first ALGOL system, but a decent one even though they did put a bunch of Fortran-like ugliness into the I/O.  

PDP11 DECUS ALGOL was clearly inspired by that, it’s a subset of Burroughs ALGOL and the generated code looks like a 16-bit variant of B5500 machine code.

Note though that some of the discussion was about Algol 68, which is a rather different language.  I don’t know that Burroughs ever did anything with it, but some other companies did (CDC for one).
> Did DEC ever produce a machine that ate Algol as its native programming language?

“native” in what sense?  There are plenty of machines, from many companies, that support block structured languages well.  The PDP11 and VAX are among those, as are the Burroughs mainframes, the Electrologica EL-X8, and many others.  If so, they will do well at Algol, Pascal, C, Modula, Ada, and so on.

Some other machines don’t make stack operations and recursive functions easy, and as such could be called “Fortran machines” — CDC 6000 series, IBM 360, and PDP-8 are examples.  Still, with a bit of extra work those too can handle Algol and other block-structured languages.  After all, the first Pascal was implemented on the CDC 6600 (by ETH Zürich).  And CDC shipped both Algol 60 and Algol 68 compilers.  IBM had an Algol 60 for OS/360, as I recall, though I’ve never used it.

If you mean “native” in the sense of an instruction set tailored for running Algol programs, no — in that sense, Burroughs was rather unusual, though you might point at the Electrologica EL-X8 as another example.


More information about the cctech mailing list