interpret/validity: reject references to uninhabited types #97116
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Some changes occured to the CTFE / Miri engine cc @rust-lang/miri |
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@bors r+ rollup |
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Rollup of 7 pull requests Successful merges: - rust-lang#96647 (rustdoc-json: Fix HRTBs for WherePredicate::BoundPredicate) - rust-lang#96651 (Omit unnecessary help to add `#[cfg(test)]` when already annotated) - rust-lang#96761 (rustdoc: don't build `rayon` for non-windows targets) - rust-lang#97096 (Types with reachable constructors are reachable) - rust-lang#97097 (Add tmm_reg clobbers) - rust-lang#97113 (Search GUI fixes) - rust-lang#97116 (interpret/validity: reject references to uninhabited types) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
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test for validity of references pointing to uninhabited types The new tests for rust-lang/rust#97116
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According to https://doc.rust-lang.org/reference/behavior-considered-undefined.html, this is definitely UB. And we can check this without actually looking up anything in memory, we just need the reference value and its type, making this a great candidate for a validity invariant IMO and my favorite resolution of rust-lang/unsafe-code-guidelines#77.
With this PR, Miri with
-Zmiri-check-number-validityimplements all my preferred options for what the validity invariants of our types could be. :)CTFE has been doing recursive checking anyway, so this is backwards compatible but might change the error output. I will submit a PR with the new Miri tests soon.
r? @oli-obk