Use MaybeUninit to avoid aliasing Vec and String while they can be moved.
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Vec and String while they are being moved.Vec and String while they are being moved.
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Vec and String while they are being moved.MaybeUninit to avoid aliasing Vec and String while they can be moved.
This avoids having a real reference to the source data, which should avoid UB from aliasing the `String`/`Vec`.
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The idea is: by storing the wrapped
Templateheld byTemplateBufinMaybeUninit, we're not really storing a reference to the source data. Or at-least not as far as the compiler is aware.Instead, we "recreate" the
Templatewith reference to the source data when we useMaybeUninit::assume_init_ref().I'm not 100% sure this is totally sound, but
miriaccepts it. The PR also addscargo miri testto the CI workflow.The PR also switches to
Pin<String>andPin<Vec<u8>>, although that currently doesn't actually do anything about aliasing rules.Pinmay have different aliasing rules in the future, which will likely be more appropriate.