Enable clippy lint borrow_as_ptr

[y86-dev]

Clean the tree for any errors that would occur and then enable the clippy lint borrow_as_ptr.

---

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[tamird]

Note that this lint is MSRV-aware. Because &raw syntax was stabilized in 1.82.0, the lint is no-op until we bump the MSRV in our .clippy.toml.

This kind of thing will continue to bite us as long as we use unstable features because the MSRV infrastructure in clippy is not #[feature]-aware. We could request that in clippy but I suspect it'd be a good bit of work to implement.

[y86-dev]

Note that this lint is MSRV-aware. Because &raw syntax was stabilized in 1.82.0, the lint is no-op until we bump the MSRV in our .clippy.toml.

That is a bit annoying... Thanks for noticing it :) Do you know what the advantages of having a msrv in .clippy.toml? (If you don't, maybe @ojeda knows?)

This kind of thing will continue to bite us as long as we use unstable features because the MSRV infrastructure in clippy is not #[feature]-aware. We could request that in clippy but I suspect it'd be a good bit of work to implement.

Since they can't change the current behavior from 1.78-1.85, it won't help us at the moment...

[tamird]

Note that this lint is MSRV-aware. Because &raw syntax was stabilized in 1.82.0, the lint is no-op until we bump the MSRV in our .clippy.toml.

That is a bit annoying... Thanks for noticing it :) Do you know what the advantages of having a msrv in .clippy.toml? (If you don't, maybe @ojeda knows?)

I imagine the intent is that you get more uniform behavior regardless of the rustc version you happen to be using.

This kind of thing will continue to bite us as long as we use unstable features because the MSRV infrastructure in clippy is not #[feature]-aware. We could request that in clippy but I suspect it'd be a good bit of work to implement.

Since they can't change the current behavior from 1.78-1.85, it won't help us at the moment...

True.

[ojeda]

Do you know what the advantages of having a msrv in .clippy.toml? (If you don't, maybe @ojeda knows?)

The justification was on f0915ac ("rust: give Clippy the minimum supported Rust version"), which mentioned the disadvantage -- if we are losing too much we care about, then we could comment it for the time being and then re-enable it e.g. when we bump to the new MSRV.

Since they can't change the current behavior from 1.78-1.85, it won't help us at the moment...

If it worked, then I guess it wouldn't be too bad to have those Clippy lints only working on the newer ones -- we would be in a similar situation like an existing lint catching more cases in a new release, if I understand correctly.

Sadly, 1.85 will likely be the next Debian one. Even if it wasn't, eventually there will be enough developers using only distro versions and thus not seeing all lints anyway, whatever the reason behind it. So we will have to deal with situations like this and do asynchronous cleanups (we already had to, in fact).

Anyway, this is all assuming Clippy would give us something to say "we actually use this particular feature across all our supported versions".

[tamird]

Filed it. rust-lang/rust-clippy#14477

[ojeda]

Thanks! Added a couple notes there and linked back.