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| author | lcnr <rust@lcnr.de> | 2022-11-23 17:39:51 +0100 |
|---|---|---|
| committer | lcnr <rust@lcnr.de> | 2022-11-25 11:59:08 +0100 |
| commit | 84e97907c64646b6ad960f6721aafc0a1c1c0503 (patch) | |
| tree | 312307d66a85c60811d845492df28723374245dd | |
| parent | 31431ccda9bbedccb09381d05700b8171eae3ae7 (diff) | |
| download | rust-84e97907c64646b6ad960f6721aafc0a1c1c0503.tar.gz rust-84e97907c64646b6ad960f6721aafc0a1c1c0503.zip | |
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| -rw-r--r-- | compiler/rustc_middle/src/traits/select.rs | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/compiler/rustc_middle/src/traits/select.rs b/compiler/rustc_middle/src/traits/select.rs index 5bb8842ebe9..ec69864c951 100644 --- a/compiler/rustc_middle/src/traits/select.rs +++ b/compiler/rustc_middle/src/traits/select.rs @@ -105,6 +105,12 @@ pub type EvaluationCache<'tcx> = Cache< /// parameter environment. #[derive(PartialEq, Eq, Debug, Clone, TypeFoldable, TypeVisitable)] pub enum SelectionCandidate<'tcx> { + /// A builtin implementation for some specific traits, used in cases + /// where we cannot rely an ordinary library implementations. + /// + /// The most notable examples are `sized`, `Copy` and `Clone`. This is also + /// used for the `DiscriminantKind` and `Pointee` trait, both of which have + /// an associated type. BuiltinCandidate { /// `false` if there are no *further* obligations. has_nested: bool, |