incorrectly prefer builtin dyn impls :3 #141347
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rustbot added S-waiting-on-review 
compiler-errors changed the title dyn impls :3 
compiler-errors approved these changes May 21, 2025
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| good enough @bors r+ rollup |
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bors added a commit to rust-lang-ci/rust that referenced this pull request May 21, 2025
builtin dyn impl no guide inference cc rust-lang#141347 we can already slightly restrict this behavior in the old solver, so why not do so. Needs crater and an FCP. r? `@compiler-errors`
bors added a commit to rust-lang-ci/rust that referenced this pull request May 21, 2025
…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#140526 (docs: Specify that common sort functions sort in an ascending direction) - rust-lang#141230 (std: fix doctest and explain for `as_slices` and `as_mut_slices` in `VecDeque`) - rust-lang#141341 (limit impls of `VaArgSafe` to just types that are actually safe) - rust-lang#141347 (incorrectly prefer builtin `dyn` impls :3) - rust-lang#141351 (Move -Zcrate-attr injection to just after crate root parsing) - rust-lang#141356 (lower bodies' params to thir before the body's value) - rust-lang#141357 (`unpretty=thir-tree`: don't require the final expr to be the body's value) - rust-lang#141363 (Document why we allow escaping bound vars in LTA norm) r? `@ghost` `@rustbot` modify labels: rollup
rust-timer added a commit to rust-lang-ci/rust that referenced this pull request May 22, 2025
Rollup merge of rust-lang#141347 - lcnr:lets-make-it-unsound-3, r=compiler-errors incorrectly prefer builtin `dyn` impls :3 This makes rust-lang#57893 slightly more exploitable with the new solver. It's still strictly better than the old solver and the underlying unsoundness persists in the new one even without this preference. Properly fixing rust-lang#57893 is something we've been looking at more deeply recently and discussed at the [Types Meetup during the All-Hands](https://hackmd.io/rz-4ghMzTb2wXOkdLKHaHw#Dyn-traits). Whatever approach we'll end up deciding on will likely require a fairly long transition period and some significant further design work. This should not block `-Znext-solver`. fixes rust-lang/trait-system-refactor-initiative#183 r? `@compiler-errors` cc `@rust-lang/types`
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workingjubilee added a commit to workingjubilee/rustc that referenced this pull request Jun 14, 2025
…iler-errors builtin dyn impl no guide inference cc rust-lang#141347 we can already slightly restrict this behavior in the old solver, so why not do so. Needs crater and an FCP. r? `@compiler-errors`
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This makes #57893 slightly more exploitable with the new solver. It's still strictly better than the old solver and the underlying unsoundness persists in the new one even without this preference.
Properly fixing #57893 is something we've been looking at more deeply recently and discussed at the Types Meetup during the All-Hands. Whatever approach we'll end up deciding on will likely require a fairly long transition period and some significant further design work. This should not block
-Znext-solver.fixes rust-lang/trait-system-refactor-initiative#183
r? @compiler-errors cc @rust-lang/types