I may have bad news for you on how compilers typically work.
A language or a library might change the implementation of a sorting algorithm once in a few years. An LLM is likely to do it every time you regenerate the code.
It’s not just a matter of non-determinism either, but about how chaotic LLMs are. Compilers can produce different machine code with slightly different inputs, but it’s nothing compared to how wildly different LLM output is with very small differences in input. Adding a single word to your spec file can cause the final code to be far more unrecognizably different than adding a new line to a C file.
If you are only checking in the spec which is the logical conclusion of “this is the new high level language”, everyone you regenerate your code all of the thousands upon thousands of unspecified implementation details will change.
Oops I didn’t think I needed to specify what going to happen when a user tries to do C before A but after B. Yesterday it didn’t seem to do anything but today it resets their account balance to $0. But after the deployment 5 minutes ago it seems to be fixed.
Sometimes users dragging a box across the screen will see the box disappear behind other boxes. I can’t reproduce it though.
I changed one word in my spec and now there’s an extra 500k LOC to implement a hidden asteroids game on the home page that uses 100% of every visitor’s CPU.
This kind of stuff happens now, but the scale with which it will happen if you actually use LLMs as a high level language is unimaginable. The chaos of all the little unspecified implementation details constantly shifting is just insane to contemplate as user or a maintainer.
I think GP was referring to heuristics and PGO.
Two runs of the same programme can produce different machine code from the JIT compiler, unless everything in the universe that happened in first execution run, gets replicated during the second execution.
And the vast, vast majority of the time, adding a new line to the source code will not result in an unrecognizably different output.
With an LLM changing one word can and frequently does cause the out to be so 100% different. Literally no lines are the same in a diff. That’s such a vastly different scope of problem that comparing them is pointless.
Likewise, as long as the agent delivers the same outcome, e.g. an email is sent with a specific subject and body, the observed behaviour remains.
That is not true for an English language prompt like “send and email with this specific subject and body”. There are so many implicit decisions that have to be made in that statement that will be different every time you regenerate the code.
English language specs will always have this ambiguity.
https://microsoftedge.github.io/edgevr/posts/Super-Duper-Sec...
Also the exact sequence of generated machine instructions depends of various factors, the same source can have various outputs, depending on code execution, preset hardware, and heuristics.
And 10 orders is optimistic value - LLMs are random with some probability of solving the real problem (and I think of real systems, not a PoC landing page or 2-3 models CRUD) now. Every month they are now getting visibly better of course.
The „old” world may output different assembly or bytecode everytime, but running it will result in same outputs - maybe slower, maybe faster. LLMs now for same prompt can generate working or non-working or - faking solution.
As always - what a time to be alive!