[jeff-davis]

The article addresses this: "However - and this is the big, enormous caveat of this section - this would rely on the compiler effectively implementing some kind of unbreakable firewall, to prevent a type that does not implement Leak from ever getting used with pre-2024 code."

[amluto]

What I mean is: instead of having a “firewall” in the compiler, is there a way to interpret pre-2024 code such that it has correct but conservative Leak bounds? Then there would be more confidence that, if a mixed-edition program type-checks, then it’s correct.

[ComputerGuru]

It took me a minute, but the firewall is talking about the reverse direction of preventing post-2024 code without Leak being used in pre-2024 code.