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Double-frees are prevented by Vale's single ownership (in the C++ sense), generational references make it so use-after-frees are safely detected. If we try to access released memory via a reference, we should predictably+safely get either a segmentation fault or an assertion failure (and a future improvement involving remapping virtual space will make it so we get no segmentation faults, which I'm pretty excited for). Hope that helps!

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> Double-frees are prevented by Vale's single ownership (in the C++ sense)

...wouldn't that also be prevented by the generation-check even if there is no single-ownership? Because once the referenced item is destroyed (and thus bumping that "memory slot's" generation counter) that item reference becomes invalid because the generation no longer matches, so the next attempt to release the item with that same reference should also fail?

One nice property of generational-indices is that they can be shared without compromising memory safety. As soon as the item is destroyed, all shared references in the wild automatically become invalid. But I guess single-ownership still makes a lot of sense for thread-safety :)

How is Vale's memory safety approach different than CCured?

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