Remove the precise_pointer_size_matching feature gate
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tests/ui/feature-gates/feature-gate-precise_pointer_size_matching.stderr
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…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#117922 (Tweak unclosed generics errors) - rust-lang#118471 (Fix typos in README.md) - rust-lang#118594 (Remove mention of rust to make the error message generic.) - rust-lang#118598 (Remove the `precise_pointer_size_matching` feature gate) - rust-lang#118606 (Fix `x` not to quit after `x` prints `settings.json`) - rust-lang#118608 (Use default params until effects in desugaring) - rust-lang#118614 (Update books) - rust-lang#118637 (rustc_symbol_mangling,rustc_interface,rustc_driver_impl: Enforce `rustc::potential_query_instability` lint) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#118598 - Nadrieril:remove_precise_pointer_size_matching, r=davidtwco Remove the `precise_pointer_size_matching` feature gate `usize` and `isize` are special for pattern matching because their range might depend on the platform. To make code portable across platforms, the following is never considered exhaustive: ```rust let x: usize = ...; match x { 0..=18446744073709551615 => {} } ``` Because of how rust handles constants, this also unfortunately counts `0..=usize::MAX` as non-exhaustive. The [`precise_pointer_size_matching`](rust-lang#56354) feature gate was introduced both for this convenience and for the possibility that the lang team could decide to allow the above. Since then, [half-open range patterns](rust-lang#67264) have been implemented, and since rust-lang#116692 they correctly support `usize`/`isize`: ```rust match 0usize { // exhaustive! 0..5 => {} 5.. => {} } ``` I believe this subsumes all the use cases of the feature gate. Moreover no attempt has been made to stabilize it in the 5 years of its existence. I therefore propose we retire this feature gate. Closes rust-lang#56354
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usizeandisizeare special for pattern matching because their range might depend on the platform. To make code portable across platforms, the following is never considered exhaustive:Because of how rust handles constants, this also unfortunately counts
0..=usize::MAXas non-exhaustive. Theprecise_pointer_size_matchingfeature gate was introduced both for this convenience and for the possibility that the lang team could decide to allow the above.Since then, half-open range patterns have been implemented, and since #116692 they correctly support
usize/isize:I believe this subsumes all the use cases of the feature gate. Moreover no attempt has been made to stabilize it in the 5 years of its existence. I therefore propose we retire this feature gate.
Closes #56354