1 files changed, 21 insertions, 5 deletions
diff --git a/compiler/rustc_middle/src/ty/generics.rs b/compiler/rustc_middle/src/ty/generics.rs
index add2df258..0c8bdde9c 100644
--- a/compiler/rustc_middle/src/ty/generics.rs
+++ b/compiler/rustc_middle/src/ty/generics.rs
@@ -1,4 +1,3 @@
-use crate::middle::resolve_lifetime::ObjectLifetimeDefault;
 use crate::ty;
 use crate::ty::subst::{Subst, SubstsRef};
 use crate::ty::EarlyBinder;
@@ -13,7 +12,7 @@ use super::{EarlyBoundRegion, InstantiatedPredicates, ParamConst, ParamTy, Predi
 #[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable)]
 pub enum GenericParamDefKind {
     Lifetime,
-    Type { has_default: bool, object_lifetime_default: ObjectLifetimeDefault, synthetic: bool },
+    Type { has_default: bool, synthetic: bool },
     Const { has_default: bool },
 }
 
@@ -28,8 +27,9 @@ impl GenericParamDefKind {
     pub fn to_ord(&self) -> ast::ParamKindOrd {
         match self {
             GenericParamDefKind::Lifetime => ast::ParamKindOrd::Lifetime,
-            GenericParamDefKind::Type { .. } => ast::ParamKindOrd::Type,
-            GenericParamDefKind::Const { .. } => ast::ParamKindOrd::Const,
+            GenericParamDefKind::Type { .. } | GenericParamDefKind::Const { .. } => {
+                ast::ParamKindOrd::TypeOrConst
+            }
         }
     }
 
@@ -122,6 +122,21 @@ pub struct Generics {
 }
 
 impl<'tcx> Generics {
+    /// Looks through the generics and all parents to find the index of the
+    /// given param def-id. This is in comparison to the `param_def_id_to_index`
+    /// struct member, which only stores information about this item's own
+    /// generics.
+    pub fn param_def_id_to_index(&self, tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<u32> {
+        if let Some(idx) = self.param_def_id_to_index.get(&def_id) {
+            Some(*idx)
+        } else if let Some(parent) = self.parent {
+            let parent = tcx.generics_of(parent);
+            parent.param_def_id_to_index(tcx, def_id)
+        } else {
+            None
+        }
+    }
+
     #[inline]
     pub fn count(&self) -> usize {
         self.parent_count + self.params.len()
@@ -252,7 +267,7 @@ impl<'tcx> Generics {
         // Filter the default arguments.
         //
         // This currently uses structural equality instead
-        // of semantic equivalance. While not ideal, that's
+        // of semantic equivalence. While not ideal, that's
         // good enough for now as this should only be used
         // for diagnostics anyways.
         own_params.end -= self
@@ -314,6 +329,7 @@ impl<'tcx> GenericPredicates<'tcx> {
         }
     }
 
+    #[instrument(level = "debug", skip(self, tcx))]
     fn instantiate_into(
         &self,
         tcx: TyCtxt<'tcx>,