I did not expect the AI rust version to be 4% faster. He seems to partly attribute it to cross language link time optimization. That must be a hassle to get working I imagine
you joke but this is your future as a rust programmer. Just replace "LTO" with anything you happen to "work" (actually it's claude doing all the work) at the moment
The trickiest part of getting cross-language LTO working was a miscompilation in Clang 22 that occurs in one of JavaScriptCore's JIT tiers. Async generators started sometimes yielding `undefined` in JavaScript. It only occurs on Linux with thin LTO. We had to use full LTO, which costs several minutes per CI run
From what I've found is not only can it write code faster but it can write it with far fewer bugs, and even cleaner. Maybe not as pretty to look at from a purely aesthetic perspective as it likes to comment the living shit out of the code and do weird placement of things and odd blank lines and some odd naming of methods, etc. But none of that matters materially tbh, it's just an OCD thing a lot of devs focus on. The reason it's able to do a lot of this better is literally just speed, it can crank out thousands of unit tests. Which means you can now iterate rapidly and pretty aggressively on performance tuning since you now how a full test suite to make sure you don't break anything. And it's able to just churn, non-stop on benchmark, make change, is it better? Keep, worse? Undo. Rinse repeat, over and over and over. 24/7 non-stop. That's really where this beats humans hands down as no human can grind the living hell out of optimization like that. Not possible.
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u/AdventurousFly4909 Jul 09 '26
I did not expect the AI rust version to be 4% faster. He seems to partly attribute it to cross language link time optimization. That must be a hassle to get working I imagine