Ways to leak Unmovable type

help
#1

I'm currently playing with with "Unmovable" type taken from this github issue comment (credit @Kimundi). I've ported it to work with modern Rust versions: playground link.

I am trying to think of ways to leak it. So far I've found only one: locking the type in an async block and leaking that block (playground link).

Does anyone know of any other way to leak this Unmovable type?

#2

Well, trivially, you could leak it before it is locked using Box::leak().

#3

ManuallyDrop ala this playground.

#4

Nice! I'm surprised it never crossed my mind to leak it before locking

#5

oh wow. no heap needed at all. nice!

#6

FWIW, this ManuallyDrop escape hatch is precisely what prevented this "idiom" into leading to a function-backed implementation of stack pinning (so close though).

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#7

Also, you can just exit without running destuctors. Or have your thread killed, perhaps implicitly. The latter is probably something like what is happening with your async block.

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