alt Hacker NewsPoster here. I re-read this paper about once a year. I continue to think that it may be one of the most important papers I've read. As someone who works on high-reliability safety-critical real-time systems (automotive, avionics), being able to work in an environment where I could prove semantic properties of assembly code is pretty close to my dream -- the cost of demonstrating code correct is already so much higher than the cost of writing the code that the incremental cost of going to assembly seems minor, if there's even a small payback in time to demonstrate correctness. In practice, I think my dream language would be a relatively rich macro assembler plus a (guided, greedy) register allocator, designed entirely to simplify and allow semantic proofs. I don't really have a sense as to whether Coq (Rocq) is the right answer today, vs other options; or if there's a newer literature advancing this approach; but I'd truly love to see a deeper focus of making low level languages more useful in this space, rather than moving towards more constrained, higher level languages.
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The second your macro-assembler has a significantly complex syntax, you are done: feature creep for 2042 features then 2043 then 2044... and it mechanically reduces the number the alternative implementations and make the effort required to develop a new more and more unreasonable.
In this end, it is all about the complexity and stability in time for this matter.
During the days I was studying/working with Coq, one visiting professor gave a presentation on defense software design. An example presented was control logic for F-16, which the professor presumably worked on. A student asked how do you prove "correctness", i.e. operability, of a jet fighter and its control logic? I don't think the professor had a satisfying answer.
My question is the same, albeit more technically refined. How do you prove the correctness of a numerical algorithm (operating on a quantized continuum) using type-theoretic/category-theoretic tools like theorem provers like Coq? There are documented tragedies where numerical rounding error of the control logic of a missile costed lives. I have proved mathematical theorems before (Curry-Howard!) but they were mathematical object driven (e.g. sets, groups) not continuous numbers.