Auto merge of #109762 - scottmcm:variantdef-indexvec, r=WaffleLapkin

Update `ty::VariantDef` to use `IndexVec<FieldIdx, FieldDef>`

And while doing the updates for that, also uses `FieldIdx` in `ProjectionKind::Field` and `TypeckResults::field_indices`.

There's more places that could use it (like `rustc_const_eval` and `LayoutS`), but I tried to keep this PR from exploding to *even more* places.

Part 2/? of https://github.com/rust-lang/compiler-team/issues/606

3 files changed, 3 insertions, 1 deletions

diff --git a/compiler/rustc_trait_selection/src/solve/project_goals.rs b/compiler/rustc_trait_selection/src/solve/project_goals.rs
index da713268f11..e0a69438dec 100644
--- a/compiler/rustc_trait_selection/src/solve/project_goals.rs
+++ b/compiler/rustc_trait_selection/src/solve/project_goals.rs
@@ -340,7 +340,7 @@ impl<'tcx> assembly::GoalKind<'tcx> for ProjectionPredicate<'tcx> {
                 }
 
                 ty::Adt(def, substs) if def.is_struct() => {
-                    match def.non_enum_variant().fields.last() {
+                    match def.non_enum_variant().fields.raw.last() {
                         None => tcx.types.unit,
                         Some(field_def) => {
                             let self_ty = field_def.ty(tcx, substs);
diff --git a/compiler/rustc_trait_selection/src/solve/trait_goals.rs b/compiler/rustc_trait_selection/src/solve/trait_goals.rs
index f522a8f7e65..ce3db83d33d 100644
--- a/compiler/rustc_trait_selection/src/solve/trait_goals.rs
+++ b/compiler/rustc_trait_selection/src/solve/trait_goals.rs
@@ -407,6 +407,7 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> {
                     let tail_field = a_def
                         .non_enum_variant()
                         .fields
+                        .raw
                         .last()
                         .expect("expected unsized ADT to have a tail field");
                     let tail_field_ty = tcx.type_of(tail_field.did);
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index eb354bc3f50..5e60bc01bb6 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -1078,6 +1078,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 let tail_field = def
                     .non_enum_variant()
                     .fields
+                    .raw
                     .last()
                     .expect("expected unsized ADT to have a tail field");
                 let tail_field_ty = tcx.type_of(tail_field.did);