diff options
| -rw-r--r-- | compiler/rustc_infer/src/infer/higher_ranked/mod.rs | 6 | ||||
| -rw-r--r-- | compiler/rustc_typeck/src/bounds.rs | 24 | ||||
| -rw-r--r-- | compiler/rustc_typeck/src/check/method/probe.rs | 13 | ||||
| -rw-r--r-- | compiler/rustc_typeck/src/check/writeback.rs | 2 |
4 files changed, 20 insertions, 25 deletions
diff --git a/compiler/rustc_infer/src/infer/higher_ranked/mod.rs b/compiler/rustc_infer/src/infer/higher_ranked/mod.rs index 9d9ecf5b384..39043980dc4 100644 --- a/compiler/rustc_infer/src/infer/higher_ranked/mod.rs +++ b/compiler/rustc_infer/src/infer/higher_ranked/mod.rs @@ -24,9 +24,9 @@ impl<'a, 'tcx> CombineFields<'a, 'tcx> { // as-is, we need to do some extra work here in order to make sure // that function subtyping works correctly with respect to regions // - // Note: this is a subtle algorithm. For a full explanation, - // please see the large comment at the end of the file in the (inlined) module - // `doc`. + // Note: this is a subtle algorithm. For a full explanation, please see + // the rustc dev guide: + // <https://rustc-dev-guide.rust-lang.org/borrow_check/region_inference/placeholders_and_universes.html> let span = self.trace.cause.span; diff --git a/compiler/rustc_typeck/src/bounds.rs b/compiler/rustc_typeck/src/bounds.rs index 683707470f4..497754f20e4 100644 --- a/compiler/rustc_typeck/src/bounds.rs +++ b/compiler/rustc_typeck/src/bounds.rs @@ -67,22 +67,18 @@ impl<'tcx> Bounds<'tcx> { sized_predicate .into_iter() + .chain(self.region_bounds.iter().map(|&(region_bound, span)| { + let outlives = ty::OutlivesPredicate(param_ty, region_bound); + (ty::Binder::bind(outlives).to_predicate(tcx), span) + })) + .chain(self.trait_bounds.iter().map(|&(bound_trait_ref, span, constness)| { + let predicate = bound_trait_ref.with_constness(constness).to_predicate(tcx); + (predicate, span) + })) .chain( - self.region_bounds + self.projection_bounds .iter() - .map(|&(region_bound, span)| { - let outlives = ty::OutlivesPredicate(param_ty, region_bound); - (ty::Binder::bind(outlives).to_predicate(tcx), span) - }) - .chain(self.trait_bounds.iter().map(|&(bound_trait_ref, span, constness)| { - let predicate = bound_trait_ref.with_constness(constness).to_predicate(tcx); - (predicate, span) - })) - .chain( - self.projection_bounds - .iter() - .map(|&(projection, span)| (projection.to_predicate(tcx), span)), - ), + .map(|&(projection, span)| (projection.to_predicate(tcx), span)), ) .collect() } diff --git a/compiler/rustc_typeck/src/check/method/probe.rs b/compiler/rustc_typeck/src/check/method/probe.rs index 39a79893b64..891dd8b2f02 100644 --- a/compiler/rustc_typeck/src/check/method/probe.rs +++ b/compiler/rustc_typeck/src/check/method/probe.rs @@ -765,13 +765,12 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> { ) }); - // It is illegal to invoke a method on a trait instance that - // refers to the `Self` type. An error will be reported by - // `enforce_object_limitations()` if the method refers to the - // `Self` type anywhere other than the receiver. Here, we use - // a substitution that replaces `Self` with the object type - // itself. Hence, a `&self` method will wind up with an - // argument type like `&Trait`. + // It is illegal to invoke a method on a trait instance that refers to + // the `Self` type. An [`ObjectSafetyViolation::SupertraitSelf`] error + // will be reported by `object_safety.rs` if the method refers to the + // `Self` type anywhere other than the receiver. Here, we use a + // substitution that replaces `Self` with the object type itself. Hence, + // a `&self` method will wind up with an argument type like `&Trait`. let trait_ref = principal.with_self_ty(self.tcx, self_ty); self.elaborate_bounds(iter::once(trait_ref), |this, new_trait_ref, item| { let new_trait_ref = this.erase_late_bound_regions(new_trait_ref); diff --git a/compiler/rustc_typeck/src/check/writeback.rs b/compiler/rustc_typeck/src/check/writeback.rs index d1ada123c0d..68b85a4da34 100644 --- a/compiler/rustc_typeck/src/check/writeback.rs +++ b/compiler/rustc_typeck/src/check/writeback.rs @@ -88,7 +88,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } /////////////////////////////////////////////////////////////////////////// -// The Writeback context. This visitor walks the AST, checking the +// The Writeback context. This visitor walks the HIR, checking the // fn-specific typeck results to find references to types or regions. It // resolves those regions to remove inference variables and writes the // final result back into the master typeck results in the tcx. Here and |