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Dennis Ritchie’s first C compiler (c. 1972)

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Re: Dennis Ritchie’s first C compiler (c. 1972)

#11

Post by retrac »

systemvoltage wrote: post #10
retrac wrote: post #9

Earlier quoted context omitted.

It was written in B. And B was written in B. To trace the bootstrap up into the high level, you have to go further back than the PDP-11. To bootstrap B on the PDP-7 and GE-635 machines he had access too, Ritchie wrote the minimum subset required to compile a compiler in B, in a language known as TMG (in the vein of, and a big influence on, Yacc and similar). This minimal bootstrap was then used to compile a B compile…

When people say bootstrapping, is this how all computer languages came to be? Or there has been multiple attempts at bootstrapping? What I’m getting at is whether all languages have a single root.

Yes, bootstrapping with regard to languages is the trick of getting that first compiler running so you can compile the rest of the compiler.

It has been done many times. The first assemblers were written directly in machine language. The first compilers were written in assembly. Many implementations of FORTRAN, ALGOL, COBOL, etc. As late as the 1970s it was not unknown to write a new high level language directly in machine code. Steve Woz's BASIC for the Apple II was "hand-assembled", as he put it.

So, taken literally, certainly not. People still do it today as a hobby or educational project.

But if we take the question in a looser sense? Yes kind of, at least in the UNIXish world. No one has implemented a serious high level systems language, except in a high level systems language, for a long time now. Rust, for example, was initially implemented in Ocaml. And normally that's what would be called the first Rust bootstrap. But OCaml was implemented in C, probably compiled by Clang or GCC. GCC was written in C and... so on.

Often one finds it does lead back to DMR at a PDP-7. On the other hand, I strongly suspect something like IBM's COBOL compiler for their mainframes (still supported and maintained today!) would not have such a heritage.

Re: Dennis Ritchie’s first C compiler (c. 1972)

#12

Post by systemvoltage »

retrac wrote: post #11
systemvoltage wrote: post #10

Earlier quoted context omitted.

When people say bootstrapping, is this how all computer languages came to be? Or there has been multiple attempts at bootstrapping? What I’m getting at is whether all languages have a single root.

Yes, bootstrapping with regard to languages is the trick of getting that first compiler running so you can compile the rest of the compiler. It has been done many times. The first assemblers were written directly in machine language. The first compilers were written in assembly. Many implementations of FORTRAN, ALGOL, COBOL, etc. As late as the 1970s it was not unknown to write a new high level language directly in m…

Fascinating and inspiring, thank you for taking the time to distill it so clearly.

Re: Dennis Ritchie’s first C compiler (c. 1972)

#13

Post by musicale »

retrac wrote: post #11
systemvoltage wrote: post #10

Earlier quoted context omitted.

When people say bootstrapping, is this how all computer languages came to be? Or there has been multiple attempts at bootstrapping? What I’m getting at is whether all languages have a single root.

Yes, bootstrapping with regard to languages is the trick of getting that first compiler running so you can compile the rest of the compiler. It has been done many times. The first assemblers were written directly in machine language. The first compilers were written in assembly. Many implementations of FORTRAN, ALGOL, COBOL, etc. As late as the 1970s it was not unknown to write a new high level language directly in m…

> Steve Woz's BASIC for the Apple II was "hand-assembled", as he put it.

Very cool - so basically (haha) Woz's integer BASIC was bootstrapped by writing it in assembly language and translating it into machine code by hand.

I wonder if someone (Woz?) has written a 6502 assembler in integer BASIC to allow it to bootstrap itself?

Re: Dennis Ritchie’s first C compiler (c. 1972)

#14

Post by macksd »

EGreg wrote: post #8
0x003 wrote: post #6

Earlier quoted context omitted.

I think it was written in B as Ritchie extended B for the PDP-11. By that point the B compiler was written in B https://sci-hub.do/10.1145/155360.155580

Real programmers use butterflies

A reference to https://xkcd.com/378/, for those wondering.

Re: Dennis Ritchie’s first C compiler (c. 1972)

#15

Post by musicale »

systemvoltage wrote: post #10
retrac wrote: post #9

Earlier quoted context omitted.

It was written in B. And B was written in B. To trace the bootstrap up into the high level, you have to go further back than the PDP-11. To bootstrap B on the PDP-7 and GE-635 machines he had access too, Ritchie wrote the minimum subset required to compile a compiler in B, in a language known as TMG (in the vein of, and a big influence on, Yacc and similar). This minimal bootstrap was then used to compile a B compile…

When people say bootstrapping, is this how all computer languages came to be? Or there has been multiple attempts at bootstrapping? What I’m getting at is whether all languages have a single root.

Interesting article on how the original CDC 6000 Pascal compilers were bootstrapped (including the scanned source code listings as PDFs!?!):

http://pascal.hansotten.com/niklaus-wirth/cdc-6000-pascal-co...

"The method used to create the first Pascal compiler, described by U. Ammann in The Zurich Implementation, was to write the compiler in a subset of unrevised Pascal itself, then hand-translate the code to SCALLOP, a CDC specific language. The compiler was then bootstrapped, or compiled using the Pascal source code and the SCALLOP based compiler, to get a working compiler that was written in Pascal itself. Then, the compiler was extended to accept the full unrevised Pascal language."

Re: Dennis Ritchie’s first C compiler (c. 1972)

#16

Post by [deleted] »

systemvoltage wrote: post #12
retrac wrote: post #11

Earlier quoted context omitted.

Yes, bootstrapping with regard to languages is the trick of getting that first compiler running so you can compile the rest of the compiler. It has been done many times. The first assemblers were written directly in machine language. The first compilers were written in assembly. Many implementations of FORTRAN, ALGOL, COBOL, etc. As late as the 1970s it was not unknown to write a new high level language directly in m…

Fascinating and inspiring, thank you for taking the time to distill it so clearly.

[deleted]

Re: Dennis Ritchie’s first C compiler (c. 1972)

#17

Post by brianpan »

systemvoltage wrote: post #10
retrac wrote: post #9

Earlier quoted context omitted.

It was written in B. And B was written in B. To trace the bootstrap up into the high level, you have to go further back than the PDP-11. To bootstrap B on the PDP-7 and GE-635 machines he had access too, Ritchie wrote the minimum subset required to compile a compiler in B, in a language known as TMG (in the vein of, and a big influence on, Yacc and similar). This minimal bootstrap was then used to compile a B compile…

When people say bootstrapping, is this how all computer languages came to be? Or there has been multiple attempts at bootstrapping? What I’m getting at is whether all languages have a single root.

I don't know if I'm stating the obvious, but you only need to bootstrap if you're writing a compiler in the language it's compiling. So any language compiler written in a different language isn't bootstrapped.

Even if you're using a loose definition of "root" as in a parent language is any language involved in writing another language, I doubt there is one root. There are certainly have been languages and computer architectures (with assembly languages) that are independent islands.

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