Document (and test) a problem with Clone/Copy deriving.
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@bors r+ rollup Read the Zulip thread. I feel like I've heard of this problem before, but maybe just once. |
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| // | ||
| // FIXME(#124794): unfortunately this doesn't work with `#[derive(Clone)] #[derive(Copy)]`. | ||
| // When the `Clone` impl is generated the `#[derive(Copy)]` hasn't been processed and | ||
| // `has_derive_copy` hasn't been set yet. |
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This should be done as a MIR pass, or something similar, IMO, instead of having a special hack in resolve.
The current optimization is a terrible hack, that is a best effort attempt to improve on the previous similar optimization hack that was both terrible and incorrect.
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Rollup of 13 pull requests Successful merges: - #148694 (std: support `RwLock` and thread parking on TEEOS) - #148712 (Port `cfg_select!` to the new attribute parsing system) - #148760 (rustc_target: hide TargetOptions::vendor) - #148771 (IAT: Reinstate early bailout) - #148775 (Fix a typo in the documentation for the strict_shr function) - #148779 (Implement DynSend and DynSync for std::panic::Location.) - #148781 ([rustdoc] Remove unneeded `allow(rustc::potential_query_instability)`) - #148783 (add test for assoc type norm wf check) - #148785 (Replace `master` branch references with `main`) - #148791 (fix "is_closure_like" doc comment) - #148792 (Prefer to use file.stable_id over file.name from source map) - #148805 (rustc-dev-guide subtree update) - #148807 (Document (and test) a problem with `Clone`/`Copy` deriving.) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #148807 - nnethercote:doc-Copy-Clone-problem, r=saethlin Document (and test) a problem with `Clone`/`Copy` deriving. I think this is useful information. I have worked on `derive` impls quite a bit and didn't know about this issue until today. r? `@saethlin`
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Rollup of 13 pull requests Successful merges: - rust-lang/rust#148694 (std: support `RwLock` and thread parking on TEEOS) - rust-lang/rust#148712 (Port `cfg_select!` to the new attribute parsing system) - rust-lang/rust#148760 (rustc_target: hide TargetOptions::vendor) - rust-lang/rust#148771 (IAT: Reinstate early bailout) - rust-lang/rust#148775 (Fix a typo in the documentation for the strict_shr function) - rust-lang/rust#148779 (Implement DynSend and DynSync for std::panic::Location.) - rust-lang/rust#148781 ([rustdoc] Remove unneeded `allow(rustc::potential_query_instability)`) - rust-lang/rust#148783 (add test for assoc type norm wf check) - rust-lang/rust#148785 (Replace `master` branch references with `main`) - rust-lang/rust#148791 (fix "is_closure_like" doc comment) - rust-lang/rust#148792 (Prefer to use file.stable_id over file.name from source map) - rust-lang/rust#148805 (rustc-dev-guide subtree update) - rust-lang/rust#148807 (Document (and test) a problem with `Clone`/`Copy` deriving.) r? `@ghost` `@rustbot` modify labels: rollup
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I think this is useful information. I have worked on
deriveimpls quite a bit and didn't know about this issue until today.r? @saethlin