unnecessary_semicolon: do not lint if it may cause borrow errors
#14049
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| && for_each_unconsumed_temporary(cx, expr, |temporary_ty| { | ||
| if temporary_ty.has_significant_drop(cx.tcx, cx.typing_env()) | ||
| && temporary_ty | ||
| .walk() | ||
| .any(|arg| matches!(arg.unpack(), GenericArgKind::Lifetime(re) if !re.is_static())) | ||
| { | ||
| ControlFlow::Break(()) | ||
| } else { | ||
| ControlFlow::Continue(()) | ||
| } | ||
| }) | ||
| .is_break() |
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Suggestion: now that there are two lints that need to do this it probably makes sense to move this to clippy_utils/ty, since I can see how we might want to adjust the logic in here a little bit in the future (specifically the has_significant_drop I'm not sure is correct as it excludes some types with drop glue - seems like it should use needs_drop instead but I also can't quite make up a FP example so 🤷 not a problem for this PR)
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Done. The name is a bit of a mouthful, but I reflects what the function is doing (and it is quite a specialized one).
Before edition 2024, some temporaries used in scrutinees in a `match` used as the last expression of a block may outlive some referenced local variables. Prevent those cases from happening by checking that alive temporaries with significant drop do have a static lifetime. The check is performed only for edition 2021 and earlier, and for the last statement if it would become the last expression of the block.
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Before edition 2024, some temporaries used in scrutinees of a
matchused as the last expression of a block may outlive some referenced local variables. Prevent those cases from happening by checking that alive temporaries with significant drop do have a static lifetime.The check is performed only for edition 2021 and earlier, and for the last statement if it would become the last expression of the block.
changelog: [
unnecessary_semicolon]: prevent borrow errors in editions lower than 2024r? @y21