Expand addr_of[_mut] UB documentation #95117
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| /// Note, however, that the `expr` in `addr_of!(expr)` is still subject to other rules: | ||
| /// * A [dangling] pointer cannot be dereferenced. In particular, `addr_of!(*ptr::null_mut())` | ||
| /// is undefined behavior because it dereferences a null pointer. | ||
| /// * An unaligned pointer cannot be dereferenced. For example, `addr_of!((*an_unaligned_ptr).field)` |
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does unaligned deserve a link to a better description / example or will everyone that reads this have that context already?
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Good call, I've added a link there to the Type layout reference page.
Explicitly list the things you aren't allowed to do with `expr`, and add a link to the exact definition of a dangling pointer. Fixes rust-lang#94473
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| /// Note, however, that the `expr` in `addr_of!(expr)` is still subject to all | ||
| /// the usual rules. In particular, `addr_of!(*ptr::null())` is Undefined | ||
| /// Behavior because it dereferences a null pointer. | ||
| /// Note, however, that the `expr` in `addr_of!(expr)` is still subject to other rules: |
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I think it would be a good idea to make it clear that these are just the normal rules for all expr in place context, and not something specific to addr_of!.
For example, addr_of!(unsafe { unreachable_unchecked() }) is also still UB, of course. We don't want to list all language UB again here.
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ping from triage: FYI: when a PR is ready for review, send a message containing |
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closing this due to inactivity |
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Explicitly list the things you aren't allowed to do with
expr, and adda link to the exact definition of a dangling pointer.
Fixes #94473