Still-further-specializable projections are ambiguous in new solver #109619
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Some changes occurred to the core trait solver cc @rust-lang/initiative-trait-system-refactor |
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…urther-specializable, r=BoxyUwU Still-further-specializable projections are ambiguous in new solver Fixes https://github.com/rust-lang/rust/pull/108896/files#r1148450781 r? `@BoxyUwU` (though feel free to re-roll) --- This can be used to create an unsound transmute function with the new solver: ```rust #![feature(specialization)] trait Default { type Id; fn intu(&self) -> &Self::Id; } impl<T> Default for T { default type Id = T; fn intu(&self) -> &Self::Id { self } } fn transmute<T: Default<Id = U>, U: Copy>(t: T) -> U { *t.intu() } use std::num::NonZeroU8; fn main() { let s = transmute::<u8, Option<NonZeroU8>>(0); assert_eq!(s, None); } ```
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…iaskrgr Rollup of 6 pull requests Successful merges: - rust-lang#109007 (rustdoc: skip `// some variants omitted` if enum is `#[non_exhaustive]`) - rust-lang#109593 (Rustdoc Book refer to rustdoc::missing_doc_code_examples. Fixes rust-lang#109592.) - rust-lang#109595 (Improve "Auto-hide trait implementation documentation" GUI test) - rust-lang#109619 (Still-further-specializable projections are ambiguous in new solver) - rust-lang#109620 (Correct typo (`back_box` -> `black_box`)) - rust-lang#109621 (Refactor: `VariantIdx::from_u32(0)` -> `FIRST_VARIANT`) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
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Fixes https://github.com/rust-lang/rust/pull/108896/files#r1148450781
r? @BoxyUwU (though feel free to re-roll)
This can be used to create an unsound transmute function with the new solver: