don't completely reset HeadUsages
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don't completely reset `HeadUsages` This is really subtle ☠️ I've actually went and added testing for `search_graph.ignore_candidate_head_usages` to https://github.com/lcnr/search_graph_fuzz now. I should have done that when I originally implemented but didn't quite know how to do so back then. The search graph is far too subtle to think through it manually. I've added the affected proof tree to https://github.com/rust-lang/trait-system-refactor-initiative/blob/main/notes/next-solver/search-graph/general.md#keeping-provisional-cache-entries-on-rerun. It's - A - B - C (depends on B and gets dropped when rerunning) - D (does not depend on B so we keep it around when rerunning) - C (irrevant candidate) - A - B - D - C (irrevant candidate) - D - A - rerun - C (use provisional cache entry which doesn't depend on B) - D (use provisional cache entry which doesn't depend on B) Fixes the ICE in rust-lang/trait-system-refactor-initiative#246 (comment). I think this issue is brittle enough that adding that as a test isn't really useful. Any small change to the search graph will prevent it from testing this. We do test this fix via the fuzzer. r? `@BoxyUwU`
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Rollup of 15 pull requests Successful merges: - #147404 (Fix issue with callsite inline attribute not being applied sometimes.) - #147534 (Implement SIMD funnel shifts in const-eval/Miri) - #147686 (update isolate_highest_one for NonZero<T>) - #148020 (Show backtrace on allocation failures when possible) - #148204 (Modify contributor email entries in .mailmap) - #148230 (rustdoc: Properly highlight shebang, frontmatter & weak keywords in source code pages and code blocks) - #148555 (Fix rust-by-example spanish translation) - #148556 (Fix suggestion for returning async closures) - #148585 ([rustdoc] Replace `print` methods with functions to improve code readability) - #148600 (re-use `self.get_all_attrs` result for pass indirectly attribute) - #148612 (Add note for identifier with attempted hygiene violation) - #148613 (Switch hexagon targets to rust-lld) - #148644 ([bootstrap] Make `--open` option work with `doc src/tools/error_index_generator`) - #148649 (don't completely reset `HeadUsages`) - #148675 (Remove eslint-js from npm dependencies) r? `@ghost` `@rustbot` modify labels: rollup
jhpratt
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don't completely reset `HeadUsages` This is really subtle ☠️ I've actually went and added testing for `search_graph.ignore_candidate_head_usages` to https://github.com/lcnr/search_graph_fuzz now. I should have done that when I originally implemented but didn't quite know how to do so back then. The search graph is far too subtle to think through it manually. I've added the affected proof tree to https://github.com/rust-lang/trait-system-refactor-initiative/blob/main/notes/next-solver/search-graph/general.md#keeping-provisional-cache-entries-on-rerun. It's - A - B - C (depends on B and gets dropped when rerunning) - D (does not depend on B so we keep it around when rerunning) - C (irrevant candidate) - A - B - D - C (irrevant candidate) - D - A - rerun - C (use provisional cache entry which doesn't depend on B) - D (use provisional cache entry which doesn't depend on B) Fixes the ICE in rust-lang/trait-system-refactor-initiative#246 (comment). I think this issue is brittle enough that adding that as a test isn't really useful. Any small change to the search graph will prevent it from testing this. We do test this fix via the fuzzer. r? ``@BoxyUwU``
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This is really subtle ☠️ I've actually went and added testing for
search_graph.ignore_candidate_head_usagesto https://github.com/lcnr/search_graph_fuzz now. I should have done that when I originally implemented but didn't quite know how to do so back then.The search graph is far too subtle to think through it manually. I've added the affected proof tree to https://github.com/rust-lang/trait-system-refactor-initiative/blob/main/notes/next-solver/search-graph/general.md#keeping-provisional-cache-entries-on-rerun. It's
Fixes the ICE in rust-lang/trait-system-refactor-initiative#246 (comment). I think this issue is brittle enough that adding that as a test isn't really useful. Any small change to the search graph will prevent it from testing this. We do test this fix via the fuzzer.
r? @BoxyUwU