1 files changed, 7 insertions, 15 deletions
diff --git a/compiler/rustc_infer/src/infer/opaque_types.rs b/compiler/rustc_infer/src/infer/opaque_types.rs
index d5c824d4c..3a0a0494a 100644
--- a/compiler/rustc_infer/src/infer/opaque_types.rs
+++ b/compiler/rustc_infer/src/infer/opaque_types.rs
@@ -1,11 +1,12 @@
+use super::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
+use super::{DefineOpaqueTypes, InferResult};
 use crate::errors::OpaqueHiddenTypeDiag;
 use crate::infer::{DefiningAnchor, InferCtxt, InferOk};
 use crate::traits;
-use hir::def::DefKind;
 use hir::def_id::{DefId, LocalDefId};
 use hir::OpaqueTyOrigin;
+use rustc_data_structures::fx::FxIndexMap;
 use rustc_data_structures::sync::Lrc;
-use rustc_data_structures::vec_map::VecMap;
 use rustc_hir as hir;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
@@ -16,18 +17,13 @@ use rustc_middle::ty::{
     TypeVisitable, TypeVisitableExt, TypeVisitor,
 };
 use rustc_span::Span;
-
 use std::ops::ControlFlow;
 
-pub type OpaqueTypeMap<'tcx> = VecMap<OpaqueTypeKey<'tcx>, OpaqueTypeDecl<'tcx>>;
-
 mod table;
 
+pub type OpaqueTypeMap<'tcx> = FxIndexMap<OpaqueTypeKey<'tcx>, OpaqueTypeDecl<'tcx>>;
 pub use table::{OpaqueTypeStorage, OpaqueTypeTable};
 
-use super::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
-use super::InferResult;
-
 /// Information about the opaque types whose values we
 /// are inferring in this function (these are the `impl Trait` that
 /// appear in the return type).
@@ -481,9 +477,7 @@ where
                 }
             }
 
-            ty::Alias(ty::Projection, proj)
-                if self.tcx.def_kind(proj.def_id) == DefKind::ImplTraitPlaceholder =>
-            {
+            ty::Alias(ty::Projection, proj) if self.tcx.is_impl_trait_in_trait(proj.def_id) => {
                 // Skip lifetime parameters that are not captures.
                 let variances = self.tcx.variances_of(proj.def_id);
 
@@ -547,8 +541,7 @@ impl<'tcx> InferCtxt<'tcx> {
         if let Some(prev) = prev {
             obligations = self
                 .at(&cause, param_env)
-                .define_opaque_types(true)
-                .eq_exp(a_is_expected, prev, hidden_ty)?
+                .eq_exp(DefineOpaqueTypes::Yes, a_is_expected, prev, hidden_ty)?
                 .obligations;
         }
 
@@ -563,8 +556,7 @@ impl<'tcx> InferCtxt<'tcx> {
                     // FIXME(RPITIT): Don't replace RPITITs with inference vars.
                     ty::Alias(ty::Projection, projection_ty)
                         if !projection_ty.has_escaping_bound_vars()
-                            && tcx.def_kind(projection_ty.def_id)
-                                != DefKind::ImplTraitPlaceholder =>
+                            && !tcx.is_impl_trait_in_trait(projection_ty.def_id) =>
                     {
                         self.infer_projection(
                             param_env,