Comment by Groxx
10 days ago
They're particularly bad about concurrent go code, in my experience - it's almost always tutorial-like stuff, over-simplified and missing error and edge case handling to the point that it's downright dangerous to use... but it routinely slips past review because it seems simple and simple is correct, right? Go concurrency is so easy!
And then you point out issues in a review, so the author feeds it back into an LLM, and code that looks like it handles that case gets added... while also introducing a subtle data race and a rare deadlock.
Very nearly every single time. On all models.
> a subtle data race and a rare deadlock
That's a langage problem that humans face as well, which golang could stop having (see C++'s Thread Safety annotations).
For Go, there is https://pkg.go.dev/gvisor.dev/gvisor/tools/checklocks. There are some missing things from C++ Thread Safety annotations, but those could be added.
Go has a pretty good race detector already, and all it (usually) takes to enable it is passing the -race flag to go build/test/run/etc.
No language protects from dead lock.
Not true! There are a fair number of them, and they're even reasonably general-purpose, e.g. https://www.ponylang.io/
Most that can recall achieve this by simply not having any locks at all. That's feasible with some careful design.
Outside proof-oriented languages though, I'm not aware of any that prevent livelocks, much less both. When excluding stuff that's single threaded but might otherwise qualify, e.g. Elm. "Lack of progress" is what most care about though, and yeah that realm is much more "you give up too much to get that guarantee" in nearly all cases (e.g. no turing completeness).
I probably agree that they don't protect you from all deadlocks, but some languages protect you from some dead locks.
You should be using rust... mm kay :\
Doing concurrency in Rust was more complex (though not overly so) than doing it in Golang was, but the fact that the compiler will outright not let me pass mutable refs to each thread does make me feel more comfortable about doing so at all.
Meanwhile I copy-pasted a Python async TaskGroup example from the docs and still found that, despite using a TaskGroup which is specifically designed to await every task and only return once all are done, it returned the instant theloop was completed and tasks were created and then the program exited without having done any of the work.
Concurrency woo~
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So you are trying to explain concurrency to the folks who implemented CSP in both Plan9 and Go. Interesting. I should return "cspbook.pdf" back.
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Good use case for Elixir. Apparently it performs best across all programming languages with LLM completions and its concurrency model is ideal too.
https://autocodebench.github.io/
This is the exact opposite of my experience.
Claude 4.6 has been excellent with Go, and truly incompetent with Elixir, to the point where I would have serious concerns about choosing Elixir for a new project.
Shouldn't you have concerns picking Claude 4.6 for your next project if it produces subpar elixer code? Cheapy shot perhaps, but I have a feeling exotic languages will remain more exotic longer now that LLM aided development is becoming the norm.
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We live in different realities.
Opus and Sonnett practically writes the same idiomatic elixir (phoenix, mind you) code that I would have written myself, with few edits.
It's scary good.
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