WIP

Author: amandasystems

compiler/rustc_borrowck/src/handle_placeholders.rs

@@ -20,7 +20,7 @@ use crate::constraints::{ConstraintSccIndex, OutlivesConstraintSet};
 use crate::consumers::OutlivesConstraint;
 use crate::diagnostics::{RegionErrorKind, RegionErrors, UniverseInfo};
 use crate::member_constraints::MemberConstraintSet;
-use crate::region_infer::values::{LivenessValues, PlaceholderIndices};
+use crate::region_infer::values::LivenessValues;
 use crate::region_infer::{ConstraintSccs, RegionDefinition, Representative, TypeTest};
 use crate::ty::VarianceDiagInfo;
 use crate::type_check::free_region_relations::UniversalRegionRelations;
@@ -39,7 +39,6 @@ pub(crate) struct LoweredConstraints<'tcx> {
     pub(crate) type_tests: Vec<TypeTest<'tcx>>,
     pub(crate) liveness_constraints: LivenessValues,
     pub(crate) universe_causes: FxIndexMap<UniverseIndex, UniverseInfo<'tcx>>,
-    pub(crate) placeholder_indices: PlaceholderIndices,
 }
 
 impl<'d, 'tcx, A: scc::Annotation> SccAnnotations<'d, 'tcx, A> {
@@ -340,7 +339,7 @@ pub(crate) fn compute_sccs_applying_placeholder_outlives_constraints<'tcx>(
     let (definitions, has_placeholders) = region_definitions(universal_regions, infcx);
 
     let MirTypeckRegionConstraints {
-        placeholder_indices,
+        placeholder_indices: _,
         placeholder_index_to_region: _,
         liveness_constraints,
         mut outlives_constraints,
@@ -388,7 +387,6 @@ pub(crate) fn compute_sccs_applying_placeholder_outlives_constraints<'tcx>(
             outlives_constraints: Frozen::freeze(outlives_constraints),
             liveness_constraints,
             universe_causes,
-            placeholder_indices,
         };
     }
     debug!("Placeholders present; activating placeholder handling logic!");
@@ -431,7 +429,6 @@ pub(crate) fn compute_sccs_applying_placeholder_outlives_constraints<'tcx>(
         type_tests,
         liveness_constraints,
         universe_causes,
-        placeholder_indices,
     }
 }
 

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -362,13 +362,11 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             type_tests,
             mut liveness_constraints,
             universe_causes,
-            placeholder_indices,
             member_constraints,
         } = lowered_constraints;
 
         debug!("universal_regions: {:#?}", universal_region_relations.universal_regions);
         debug!("outlives constraints: {:#?}", outlives_constraints);
-        debug!("placeholder_indices: {:#?}", placeholder_indices);
         debug!("type tests: {:#?}", type_tests);
 
         let constraint_graph = Frozen::freeze(outlives_constraints.graph(definitions.len()));

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -238,17 +238,14 @@ pub(crate) struct MirTypeckResults<'tcx> {
 pub(crate) struct MirTypeckRegionConstraints<'tcx> {
     /// Maps from a `ty::Placeholder` to the corresponding
     /// `PlaceholderIndex` bit that we will use for it.
-    ///
-    /// To keep everything in sync, do not insert this set
-    /// directly. Instead, use the `placeholder_region` helper.
-    pub(crate) placeholder_indices: PlaceholderIndices,
+    pub placeholder_indices: PlaceholderIndices,
 
     /// Each time we add a placeholder to `placeholder_indices`, we
     /// also create a corresponding "representative" region vid for
     /// that wraps it. This vector tracks those. This way, when we
     /// convert the same `ty::RePlaceholder(p)` twice, we can map to
     /// the same underlying `RegionVid`.
-    pub(crate) placeholder_index_to_region: IndexVec<PlaceholderIndex, ty::Region<'tcx>>,
+    pub placeholder_index_to_region: IndexVec<PlaceholderIndex, ty::Region<'tcx>>,
 
     /// In general, the type-checker is not responsible for enforcing
     /// liveness constraints; this job falls to the region inferencer,