Stabilize ptr::slice_from_raw_parts[_mut] #68234
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Hm right let's inform the bots about the review assignee properly I confused it by asking for a group 😅 So I just picked who GitHub recommended r? @oli-obk |
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Centril
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This is two free functions in the pub const fn slice_from_raw_parts<T>(data: *const T, len: usize) -> *const [T] {…}
pub const fn slice_from_raw_parts_mut<T>(data: *mut T, len: usize) -> *mut [T] {…}@rfcbot fcp merge |
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Team member @SimonSapin has proposed to merge this. The next step is review by the rest of the tagged team members: Concerns:
Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up! See this document for info about what commands tagged team members can give me. |
rfcbot
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@rfcbot concern &raw I feel that the usefulness of this feature is tied with that of |
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@Amanieu the reason I want these methods actually has nothing to do with The problem I'm dealing with is pointer provinence. I don't know (in my current generic API setup) whether the raw pointer I'm working with is from a If I use If I use And this is ignoring the case of potentially misaligned or null pointers, which are instant UB to use with the reference functions. Ultimately, I think there are enough reasons to have these functions, even if they aren't strictly required by the memory model (for aligned non-null pointers), because they're a simple helper API when you're working with pointers to begin with that sidestep all of the thorny questions around references in pointer workloads that will remain no matter the specific memory model. TL;DR: these functions are mainly useful when you don't know provenance (dependent on memory model), alignment, or null (definitely UB today). |
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I'm convinced! @rfcbot resolve &raw |
rfcbot
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🔔 This is now entering its final comment period, as per the review above. 🔔 |
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I'm just going to go ahead and cc @rust-lang/wg-unsafe-code-guidelines just in case. This is an FCP-merge with some implication on unsafe guidelines. |
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For the record I think this stabilization makes sense. It doesn't seem to have many deep implications to me -- it is simply saying that one can construct a slice given a |
It still has some uses though -- you still need the raw methods for potentially dangling or out-of-bounds or NULL or unaligned pointers. That seems like a good enough motivation to me. |
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The final comment period, with a disposition to merge, as per the review above, is now complete. As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed. The RFC will be merged soon. |
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@bors r+ |
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📌 Commit 1c0d485 has been approved by |
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Stabilize ptr::slice_from_raw_parts[_mut] Closes #36925, the tracking issue. Initial impl: #60667 r? @rust-lang/libs In addition to stabilizing, I've adjusted the example of `ptr::slice_from_raw_parts` to use `slice_from_raw_parts` instead of `slice_from_raw_parts_mut`, which was unnecessary for the example as written.
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☀️ Test successful - checks-azure |
Closes #36925, the tracking issue.
Initial impl: #60667
r? @rust-lang/libs
In addition to stabilizing, I've adjusted the example of
ptr::slice_from_raw_partsto useslice_from_raw_partsinstead ofslice_from_raw_parts_mut, which was unnecessary for the example as written.