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made the language around immutable target of references more direct
julian-graf
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Jan 13, 2026
| verifying that references don't escape the scope of their referent. That's | ||
| because ensuring pointers are always valid is much more complicated than this. | ||
| Of course, Rust's story around ownership is much more complicated than simply | ||
| gauranteeing that references cannot outlive their target. That is |
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Suggested change
| gauranteeing that references cannot outlive their target. That is | |
| guaranteeing that references cannot outlive their target. That is |
| referent and its owners. | ||
| a naive scope analysis would be insufficient to prevent this bug because `data` | ||
| does indeed live as long as required. However, `data` is *changed* by `push(4)` | ||
| and now may have been realocated to accommodate the new value. |
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| and now may have been realocated to accommodate the new value. | |
| and now may have been reallocated to accommodate the new value. |
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| Consequently, `x` may now be referring to the old | ||
| value or memory already put to use in another process (pre-emptive multi-tasking). |
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Going into detail this far (another process & preemptive multitasking) is misleading in multiple ways:
- the actual issue of accessing free'd memory is not mentioned
- accessing free'd memory is UB
- another process & preemptive multitasking is not a requirement
Suggested change
| Consequently, `x` may now be referring to the old | |
| value or memory already put to use in another process (pre-emptive multi-tasking). | |
| Consequently, the memory location pointed to by `x` may now be free'd and therefore any attempt to dereference `x` is UB. |
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made the language around immutable target of references more direct