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by yakaccount4 1261 days ago
> A panic that comes from a memory model violation (as one example) can change the value of anything in the memory space of the program ... This isn't a doom and gloom, sky-is-falling prognostication, it's literally what is defined by the spec and memory model of the language.

I do not think you are correct. Go has a class of unrecoverable panics for this specific reason. Go also runs deferred functions after a recoverable panic, so the notion that it's unsafe to handle it, or continue executiona after doesn't hold at all - it is literally a first-class feature of the language.

I have not seen an instance of a recoverable panic that is raised _after_ such a fatal operation. If you have an example of such, I would love to see it.
1 comments
preseinger 1261 days ago
What are unrecoverable panics vs. recoverable panics? Where is that distinction defined?
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yakaccount4 1261 days ago
There seems to not be any standard list of unrecoverable panics/aborts, but this Stackoverflow post [1] has a list of a few.

As far as the user/developers are concerned, it doesn't matter too much, since you have no option to recover them, but it would be nice if it was explained if defers are still ran. I'm assuming they are not.

1. https://stackoverflow.com/questions/57486620/are-all-runtime...

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preseinger 1261 days ago
If there is no way for callers to reliably distinguish recoverable panics from unrecoverable panics, then this distinction doesn't really exist, does it? Panics are panics.
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yakaccount4 1261 days ago
I'm not sure what point you are trying to make anymore.

Of course you cannot distinguish between unrecoverable and recoverable panics, because by definition an unrecoverable panic is not recoverable. There is no caller to distinguish between it - it is killed.

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preseinger 1260 days ago
Oh. You're using the word panic to describe a superset of actual panics and other even more serious errors. Those things you call unrecoverable panics are not actually panics.

The point I'm trying to make is that panics are not errors by another name, and they are not safe to recover from in general.

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