I understand from the docs that there are still restrictions to the box pointer even if the pointee is a ZST value (the Box doc mentions validity and alignment), which makes sense.
But how expensive is it for the pointee side? Is anything actually heap-allocated?
It's easy to assume not, but I'd like to know just how expensive boxing a ZST value really is.
Nothing gets allocated if you box a zst
The Box itself still occupies normal pointer size though.
@cuviper I expected as much. So ultimately the price paid for boxing a ZST value is the size of a pointer. That's acceptable in this case.
Thanks guys!
A quick code demonstration: https://rust.godbolt.org/z/Y9c8Y7hGr
It just gives a constant pointer.
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