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Comment by estebank | Hacker News Reader

In safety critical spaces you need to be able to trace any piece of a binary back to code back to requirements. If a piece of running code is implicit in code, it makes that traceability back to requirements harder. But I'd be surprised if things like bounds checks are really a problem for that kind of analysis.

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I don’t see the issue. The operations which produce a bounds check are traceable back to the code which indexes into something.

What tools do you use for this? PlantUML?

Yeah sounds too clever by half, memory safe languages are less safe because they have bounds checks...maybe I could see it on a space shuttle? Well, only in the most CYA scenarios, I'd imagine.

> maybe I could see it on a space shuttle?

"Airbus confirms that SQLite is being used in the flight software for the A350 XWB family of aircraft."

https://www.sqlite.org/famous.html

Bear in mind that SQLite is used in embedded systems, and I absolutely wouldn’t be surprised to learn it’s in space.

Critical applications like that used to use ADA to get much more sophisticated checking than just bounds. No certified engineer would (should) ever design a safety critical system without multiple “unreachable” fail safe mechanisms

Next they’ll have to tell me about how they had to turn off inlining because it creates copies of code which adds some dead branches. Bounds checks are just normal inlined code. Any bounds checked language worth its salt has that coverage for all that stuff already.

SQLite is used in a lot of hypercritical application areas. I’d almost be surprised if it’s not part of some if not all modern spaceflight stacks.

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