Zero-initialize vec![None; n] for Option<&T>, Option<&mut T> and Option<Box<T>>
#64893
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…d `Option<Box<T>>`
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r? @sfackler (rust_highfive has picked a reviewer for you, use r? to override) |
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| @@ -1748,6 +1748,31 @@ unsafe impl<T: ?Sized> IsZero for *mut T { | |||
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| } | |||
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| // `Option<&T>`, `Option<&mut T>` and `Option<Box<T>>` are guaranteed to represent `None` as null. | |||
| // For fat pointers, the bytes that would be the pointer metadata in the `Some` variant | |||
| // are padding in the `None` variant, so ignoring them and zero-initializing instead is ok. | |||
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r? @RalfJung |
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r? @sfackler |
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@bors r+ |
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📌 Commit 6c01c0e has been approved by |
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…ckler Zero-initialize `vec![None; n]` for `Option<&T>`, `Option<&mut T>` and `Option<Box<T>>`
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…ckler Zero-initialize `vec![None; n]` for `Option<&T>`, `Option<&mut T>` and `Option<Box<T>>`
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Rollup of 9 pull requests Successful merges: - #64377 (Add long error explanation for E0493) - #64786 (Use https for curl when building for linux) - #64828 (Graphviz debug output for generic dataflow analysis) - #64838 (Add long error explanation for E0550) - #64891 (Fix `vec![x; n]` with null raw fat pointer zeroing the pointer metadata) - #64893 (Zero-initialize `vec![None; n]` for `Option<&T>`, `Option<&mut T>` and `Option<Box<T>>`) - #64911 (Fixed a misleading documentation issue #64844) - #64921 (Add test for issue-64662) - #64923 (Add missing links for mem::needs_drop) Failed merges: - #64918 (Add long error explanation for E0551) r? @ghost
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