Convert std::vec::raw::{init_elem, copy_memory} to methods, and remove aliasing &[] and &mut[] #10996
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Also, dramatically simplify it with some tasteful raw pointers, rather than treating everything as a nail with `transmute`.
| /// Copies data from `src` to `self` | ||
| /// | ||
| /// Fails if `self` is shorter than `src`. | ||
| #[inline] |
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You saw nothing... :p
(thanks)
docs for copy_memory. &mut [u8] and &[u8] really shouldn't be overlapping at all (part of the uniqueness/aliasing guarantee of &mut), so no point in encouraging it.
It is required that &mut[]s are disjoint from all other &(mut)[]s, so this assumption is ok.
bors
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The removal of the aliasing &mut[] and &[] from `shift_opt` also comes with its simplification. The above also allows the use of `copy_nonoverlapping_memory` in `[].copy_memory` (I did an audit of each use of `.copy_memory` and `std::vec::bytes::copy_memory`, and I believe none of them are called with arguments can ever alias). This changes requires that `unsafe` code using `copy_memory` **needs** to respect the aliasing rules of `&mut[]`.
flip1995
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Lint `mem_forget` if any fields are `Drop` Closes rust-lang#9298 I think this way of doing it (`needs_drop`) should be fine. --- changelog: Enhancement: [`mem_forget`]: Now lints on types with fields that implement `Drop` [rust-lang#10996](rust-lang/rust-clippy#10996)
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The removal of the aliasing &mut[] and &[] from
shift_optalso comes with its simplification.The above also allows the use of
copy_nonoverlapping_memoryin[].copy_memory(I did an audit of each use of.copy_memoryandstd::vec::bytes::copy_memory, and I believe none of them are called with arguments can ever alias). This changes requires thatunsafecode usingcopy_memoryneeds to respect the aliasing rules of&mut[].