Address concerns of weak-into-raw #71107
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* Rename Weak::as_raw to Weak::as_ptr for consistency with some other types. * The as_ptr for a dangling Weak pointer might return whatever garbage (and takes that advantage to avoid a conditional). * Don't guarantee to be able to do `Weak::from_raw(weak.as_ptr())` (even though it'll still work fine).
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r? @Amanieu |
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cc @RalfJung |
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r=me once the issues with the doc comments are fixed. |
For consistency with Weak
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Thanks. I've forced-pushed it directly, but the only change is the rewording of the comment. |
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@bors r+ rollup |
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📌 Commit f4ded11 has been approved by |
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…anieu Address concerns of weak-into-raw This should address the standing concerns in rust-lang#60728 (comment). I've still left the ability to create a new dangling pointer from `null`, as I feel like this is the natural behaviour to expect, but I'm fine removing that too. I've modified the documentation to allow the `as_ptr` or `into_ptr` to return whatever garbage in case of a dangling pointer. I've also removed the guarantee to be able to do `from_raw(as_ptr)` from the documentation (but it would still work right now). I've renamed the method and added implementations for `Rc`/`Arc`. I've also tried if I can just „enable“ unsized types. I believe the current interface is compatible with them. But the inner implementation will be a bit challenging ‒ I can't use the `data_offset` as is used by `Rc` or `Arc` because it AFAIK „touches“ (creates a reference to) the live value of `T` ‒ and in case of `Weak`, it might be completely bogus or already dead ‒ so that would be UB. `./x.py test tidy` is completely mad on my own system all over the code base :-(. I'll just hope it goes through CI, or will fix as necessary. Is it OK if I ask @Amanieu for review, as the concerns are from you? ~r @Amanieu
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Rollup of 5 pull requests Successful merges: - rust-lang#71107 (Address concerns of weak-into-raw) - rust-lang#71188 (Fixed missing trait method suggests incorrect code (self parameter not named "self"). ) - rust-lang#71300 (Clarify when to use the tracking issue template) - rust-lang#71315 (Add example in the alternative in std::mem::transmute docs) - rust-lang#71319 (Clean up E0522 explanation) Failed merges: r? @ghost
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This should address the standing concerns in #60728 (comment).
I've still left the ability to create a new dangling pointer from
null, as I feel like this is the natural behaviour to expect, but I'm fine removing that too. I've modified the documentation to allow theas_ptrorinto_ptrto return whatever garbage in case of a dangling pointer. I've also removed the guarantee to be able to dofrom_raw(as_ptr)from the documentation (but it would still work right now).I've renamed the method and added implementations for
Rc/Arc.I've also tried if I can just „enable“ unsized types. I believe the current interface is compatible with them. But the inner implementation will be a bit challenging ‒ I can't use the
data_offsetas is used byRcorArcbecause it AFAIK „touches“ (creates a reference to) the live value ofT‒ and in case ofWeak, it might be completely bogus or already dead ‒ so that would be UB../x.py test tidyis completely mad on my own system all over the code base :-(. I'll just hope it goes through CI, or will fix as necessary.Is it OK if I ask @Amanieu for review, as the concerns are from you?
~r @Amanieu