We tasked Opus 4.6 using agent teams to build a C Compiler • Hacker News Board

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#721

Post by sarchertech » Sat, Feb 07, 2026, 12:41 AM UTC

signatoremo wrote: post #714

sarchertech wrote: post #586

Earlier quoted context omitted.

Claude was reverse engineering gcc. It was using it as an oracle and attempting to exactly march its output. That is the definition of reverse engineering. Since Claude was trained on the gcc source code, that’s not a clean room implementation. > By your definition no one can do a clean room implementation if they've taken a recent compilers course at university. Clean room implementation has a very specific definiti…

There is no specific definition of clean room implementation. Please provide source for your claim otherwise. There are many well known examples of clean room implementation. One example that survived lawsuits is Sony v. Connectix: During production, Connectix unsuccessfully attempted a Chinese wall approach to reverse engineer the BIOS, so its engineers disassembled the object code directly. Connectix's successful a…

“clean room implementation” is a term of art with a specific meaning. It has no statutory definition though so you’re technically right. But it is a defense against copyright infringement because you can’t infringe on copyright without knowledge of the material.

>During production, Connectix unsuccessfully attempted a Chinese wall approach to reverse engineer the BIOS, so its engineers disassembled the object code directly.

This doesn’t mean what you think it means. They unsuccessfully attempted a clean room implementation. What they did do was later ruled to be fair use, but it wasn’t a clean room implementation.

Using gcc as an oracle isn’t what makes it not a clean room implementation. Prior knowledge of the source code is what makes it not a clean room implementation. Using gcc as an oracle makes it an attempt to reverse engineer gcc, it says nothing about whether it is a clean room implementation or not.

There is no definition of “clean room implementation” that allows knowledge of source code. Otherwise it’s not a clean room implementation. It’s just reverse engineering/copying.

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#722

Post by sarchertech » Sat, Feb 07, 2026, 1:24 AM UTC

qarl wrote: post #652

rezonant wrote: post #555

Earlier quoted context omitted.

I can't stress enough how much LOC is not a measure of anything .

OK, well, the people in MY software industry use LOC as an informal measure of complexity. LIKE THE WHOLE WORLD DOES. But hey, maybe it's just the extremely high profile projects I've worked on.

As an informal measure of the complexity of the code sure 100k lines are inherently more complex than 10k because there’s just more there to look at. And if you are assuming that 2 projects were made by competent teams, saying that one application is 10k LOC and one is 1 million might be useful as a heuristic for number of man hours spent.

But I can write a 100k LOC compiler where 90k lines are for making error messages look pixel perfect on 10 different operating systems. Or where 90k lines are useless layers upon layers of indirection. That doesn’t mean that someone is willing to pay more for it.

AI frequently does exactly that kind of thing.

So saying my AI made a 100k LOC program that does X, and then comparing the cost to a 100k LOC program written by a human is a nonsense comparison. The only thing that matters is to compare it to how much a company would pay a human to produce a program capable of the same output.

In this case the program is commercially useless. Literally of zero monetary value, so no company would pay any money for it. Therefore there’s nothing to compare it to.

That’s not to say it’s not an interesting and useful experiment. Or that things can’t be different in the future.

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#723

Post by m463 » Sat, Feb 07, 2026, 1:36 AM UTC

ndesaulniers wrote: post #165

I spent a good part of my career (nearly a decade) at Google working on getting Clang to build the linux kernel. https://clangbuiltlinux.github.io/ This LLM did it in (checks notes): > Over nearly 2,000 Claude Code sessions and $20,000 in API costs It may build, but does it boot (was also a significant and distinct next milestone)? (Also, will it blend?). Looks like yes! > The 100,000-line compiler can build a bootab…

> getting Clang to build the linux kernel.

wonder if clang source is part of its model :)

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#724

Post by dgacmu » Sat, Feb 07, 2026, 3:15 AM UTC

icedchai wrote: post #394

qarl wrote: post #383

Earlier quoted context omitted.

A compiler that can build linux. That level of quality should be sufficient. Do you know any low quality programmers that write C compilers in rust THAT CAN BUILD LINUX? No you don't. They do not exist.

Yep. Building a working C compiler that compiles Linux is an impossible task for all but the top 1% of developers. And the ones that could do it have better things to do, plus they’d want a lot more than 20K for the trouble.

Some of the hardest parts of the compiler are optimization and clear error handling/reporting. If you forego those - because you're testing against a codebase that is already free of things that break compilation and have no particular performance requirements for the generated code - it's a substantially simpler task.

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#725

Post by dcre » Sat, Feb 07, 2026, 3:18 AM UTC

thesz wrote: post #707

dcre wrote: post #705

Earlier quoted context omitted.

That is not what No True Scotsman is. I’m pointing out a bad argument with weak evidence.

>>> It is a very contrived under-specified prompt. No True Prompt can be such contrived and underspecified. The article about degradation is a case study (single prompt), weakest of the studies in hierarchy of knowledge. Case studies are basis for further, more rigorous studies. And author took the time to test his assumptions and presented quite clear evidence that such degradation might be present and that we shoul…

We have investigated. Millions of people are investigating all the time and finding that the coding capacity has improved dramatically over that time. A variety of very different benchmarks say the same. This one random guy’s stupid prompt says otherwise. Come on.

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#726

Post by deaux » Sat, Feb 07, 2026, 3:58 AM UTC

HWR_14 wrote: post #599

deaux wrote: post #447

Earlier quoted context omitted.

Completely detached from reality, brainwashed SV VC's who have made dumping the norm in their bubble. I can guarantee you that 90% of successful businesses in the world made a profit their first year.

1 year seems aggressive. Successful restaurants have around the first year as the average break even timeline, with the vast majority between 6 and 18 months. They are making a profit on each sale, but there are fixed costs to running a business.

1 year isn't aggressive because of the modifier "successful". Most businesses that aren't profitable 12 months in go out of business not long after, having remained unsuccessful throughout their lifespan.

Restaurants have comparatively high start up costs and ramp up time. Compare to e.g. a store selling clothes. If for successful restaurants the average time is already a year, then in general for successful businesses it's going to be less.

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#727

Post by polyglotfacto » Sat, Feb 07, 2026, 4:11 AM UTC

conception wrote: post #632

polyglotfacto wrote: post #627

So I do think one can get value from coding agents, but that value is out of proportion compared to the investments made by the AI labs, so now they're pushing this kind of stuff which I find to be a borderline scam. Let me explain why: > the resulting compiled output is over 60kb, far exceeding the 32k code limit enforced by Linux Seems like a failure to me. > I tried (hard!) to fix several of the above limitations…

I don’t understand. This badly done work wasn’t possible at all six months ago. In six more months it will be better. It’s not a mostly static technology for the last twenty plus years.

Point is: it doesn't matter if agents can do it faster and cheaper than a team of humans: it's slop.

It's like writing a novel in a week that no one wants to read. If in six months you can do it in an hour, there is still zero value.

Agents are useful but very limited tools: I treat them a little machines that can translate high-level instructions into detailed code, but where I still need to review the output to make sure they understood what I meant; that's it. Zero autonomy; parallelism just means I can't keep up with the output and quality goes down.

I think the point of this project, like the fastrender slop thing, is to push the parallel agent narrative and have the financial markets believe this will create a lot more demand for inference on these models in the short term.

Example of someone falling for it: https://x.com/DKThomp/status/2019484169915572452

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#728

Post by polyglotfacto » Sat, Feb 07, 2026, 4:37 AM UTC

boring-human wrote: post #642

smithcoin wrote: post #628

Earlier quoted context omitted.

> This is a five-alarm fire if you're a SWE and not retiring in the next couple years. I’m sorry, but this is such a hype beast take. In my opinion this is equivalent to telling people not to learn to drive five years ago because of self driving from Tesla. How is that going? Every single line of code produced is a liability. This idea that you’re going to have “gas town” like agents running and building apps without…

> In my opinion this is equivalent to telling people not to learn to drive five years ago because of self driving Self-driving has different economics. We're reading tea leaves, true, but it's also true that software has zero marginal cost and that $20K pays for an engineer-month in SF. > Every single line of code produced is a liability. Do you have a hard spec and rock-solid test cases? If you do, you have two opti…

So let’s say you fund a single engineer for an open‑source project with $20k. The outcome will be a prototype with some interesting ideas. And yes, with a few hundred bucks' worth of AI assistance that single engineer might get much further than without (but not using any of the techniques presented in this blog). People can coalesce around the project as contributors. A seed was planted and watered a bit.

In this case, the $20k has been burned and produced zero value. Just look at the repo issues: looks like someone trying to get attention by spamming the issue tracker and opening hundreds of PRs. As an open source project, it’s a dead end.

So it doesn’t matter that this is “likely decrease in price over the next few years”? The value is zero, so even if superintelligence can produce this in an instant at zero cost in six months, the outcome is still worth zero.

You’re assuming a kind of inverse relationship between production cost and value.

In terms of quality, to anyone using those coding agents, it should be clear by now that letting them run autonomously and in parallel is a bad idea. That’s not going to change unless you believe LLMs will turn into something entirely different over time.

Note that what works with humans—social interaction creating some emergent properties like innovation—doesn’t translate to LLM agents for a simple reason: they don’t have agency, shared goals, or accountability, so the social dynamics that generate innovation can’t form.

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#729

Post by signatoremo » Sat, Feb 07, 2026, 5:46 AM UTC

sarchertech wrote: post #721

signatoremo wrote: post #714

Earlier quoted context omitted.

There is no specific definition of clean room implementation. Please provide source for your claim otherwise. There are many well known examples of clean room implementation. One example that survived lawsuits is Sony v. Connectix: During production, Connectix unsuccessfully attempted a Chinese wall approach to reverse engineer the BIOS, so its engineers disassembled the object code directly. Connectix's successful a…

“clean room implementation” is a term of art with a specific meaning. It has no statutory definition though so you’re technically right. But it is a defense against copyright infringement because you can’t infringe on copyright without knowledge of the material. >During production, Connectix unsuccessfully attempted a Chinese wall approach to reverse engineer the BIOS, so its engineers disassembled the object code di…

Again, reverse engineering is a valid use case of clean room implementation as I posted above, so you don't have a point there.

> “clean room implementation” is a term of art with a specific meaning.

What is the specific meaning you are talking about? If I set out to do a clean room implementation of some software, what do I need to do specifically so that I will prevail any copyright infringement claims? The answer is that there is no such a surefire guarantee.

Re: Sony v. Connectix, clean room is to protect against copyright infringement, and since Connectix was ruled not infringing on Sony's copyrights, their implementation is practically clean room under the law, despite all the pushbacks. If Connectix prevailed, I'm sure the C compiler in question would have prevailed as well if they got sued.

Finally, take Phoenix vs. IBM re: the former's BIOS implementation of the latter's PC:

Whenever Phoenix found parts of this new BIOS that didn't work like IBM's, the isolated programmer would be given written descriptions of the problems, but not any coded solutions that might have hinted at IBM's original version of the software - [0]

That very much sounds like using GCC as an online known-good compiler oracle to compare against in this case.

[0] - https://books.google.com/books?id=Bwng8NJ5fesC&pg=PA56#v=one...

Re: We tasked Opus 4.6 using agent teams to build a C Compiler

#730

Post by boring-human » Sat, Feb 07, 2026, 5:58 AM UTC

polyglotfacto wrote: post #728

boring-human wrote: post #642

Earlier quoted context omitted.

> In my opinion this is equivalent to telling people not to learn to drive five years ago because of self driving Self-driving has different economics. We're reading tea leaves, true, but it's also true that software has zero marginal cost and that $20K pays for an engineer-month in SF. > Every single line of code produced is a liability. Do you have a hard spec and rock-solid test cases? If you do, you have two opti…

So let’s say you fund a single engineer for an open‑source project with $20k. The outcome will be a prototype with some interesting ideas. And yes, with a few hundred bucks' worth of AI assistance that single engineer might get much further than without (but not using any of the techniques presented in this blog). People can coalesce around the project as contributors. A seed was planted and watered a bit. In this ca…

I agree that there's not a lot of value in your example, but it's the wrong example. AI writing code and humans refining it and maintaining it is probably an inferior proposition, more so if the project is FOSS.

The model I'm referring to is: "if it walks like software and quacks like software, it's software." Its writers and maintainers are AI. It has a commercial purpose. Its value comes from fulfilling its requirements.

There will be human handlers, including some who will occasionally have to dig through the dung and fix AI-idiosyncratic bugs. Fewer Ferrari designers, more Cuban 1956 Buick mechanics. It's an ugly approach, but the conjecture that, economically _or_ technically, there must be something fundamentally broken with it is very hand-wavy and dubious.

I agree that there will be less code-level innovation overall, just like artistic value production took a big hit when we went from portraits to photographs.