alt Hacker Newslongjmp, setjmp, setcontext, getcontext, makecontext, and swapcontext and whatever have no bearing on safety, memory or otherwise. What you have to deal with is what is represented by sigaction(2) and only and much later then by what you use to drive the context switch, be it io, or preemptive.
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anitil • today at 1:49 AM
The article mentions that you typically have to longjmp within the same function as setjump (or a descendant function) otherwise your stack gets cleared and you longjmp to a garbage stack. I believe this counts as memory safety? Though I don't quite understand your comment about sigaction, so maybe there's some context I'm missing.
Edit: The extra context- https://usenix.org/legacy/publications/library/proceedings/u...
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These functions can easily be misused to corrupt memory, so they very much have something to do with safety. Fil-C goes to great lengths to prevent your use of those functions leading to memory corruption or any violation of the capability model.
Fil-C also makes sigaction memory safe. That protection does allow for signal handlers to longjmp or setcontext or swapcontext