Remove some remnants

Author: jackh726

compiler/rustc_infer/src/infer/canonical/canonicalizer.rs

@@ -303,34 +303,16 @@ struct Canonicalizer<'cx, 'tcx> {
     sub_root_lookup_table: SsoHashMap<ty::TyVid, usize>,
     canonicalize_mode: &'cx dyn CanonicalizeMode,
     needs_canonical_flags: TypeFlags,
-
-    binder_index: ty::DebruijnIndex,
 }
 
 impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
     fn cx(&self) -> TyCtxt<'tcx> {
         self.tcx
     }
 
-    fn fold_binder<T>(&mut self, t: ty::Binder<'tcx, T>) -> ty::Binder<'tcx, T>
-    where
-        T: TypeFoldable<TyCtxt<'tcx>>,
-    {
-        self.binder_index.shift_in(1);
-        let t = t.super_fold_with(self);
-        self.binder_index.shift_out(1);
-        t
-    }
-
     fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> {
         match r.kind() {
-            ty::ReBound(ty::BoundVarIndexKind::Bound(index), ..) => {
-                if index >= self.binder_index {
-                    bug!("escaping late-bound region during canonicalization");
-                } else {
-                    r
-                }
-            }
+            ty::ReBound(ty::BoundVarIndexKind::Bound(_), ..) => r,
 
             ty::ReBound(ty::BoundVarIndexKind::Canonical, _) => {
                 bug!("canonicalized bound var found during canonicalization");
@@ -407,13 +389,7 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                 self.canonicalize_ty_var(CanonicalVarKind::PlaceholderTy(placeholder), t)
             }
 
-            ty::Bound(ty::BoundVarIndexKind::Bound(debruijn), _) => {
-                if debruijn >= self.binder_index {
-                    bug!("escaping bound type during canonicalization")
-                } else {
-                    t
-                }
-            }
+            ty::Bound(ty::BoundVarIndexKind::Bound(_), _) => t,
 
             ty::Bound(ty::BoundVarIndexKind::Canonical, _) => {
                 bug!("canonicalized bound var found during canonicalization");
@@ -487,12 +463,8 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
             ty::ConstKind::Infer(InferConst::Fresh(_)) => {
                 bug!("encountered a fresh const during canonicalization")
             }
-            ty::ConstKind::Bound(ty::BoundVarIndexKind::Bound(debruijn), _) => {
-                if debruijn >= self.binder_index {
-                    bug!("escaping bound const during canonicalization")
-                } else {
-                    return ct;
-                }
+            ty::ConstKind::Bound(ty::BoundVarIndexKind::Bound(_), _) => {
+                return ct;
             }
             ty::ConstKind::Bound(ty::BoundVarIndexKind::Canonical, _) => {
                 bug!("canonicalized bound var found during canonicalization");
@@ -580,7 +552,6 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
             query_state,
             indices: FxHashMap::default(),
             sub_root_lookup_table: Default::default(),
-            binder_index: ty::INNERMOST,
         };
         if canonicalizer.query_state.var_values.spilled() {
             canonicalizer.indices = canonicalizer

compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs

@@ -14,9 +14,7 @@ use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
 use rustc_hir::{self as hir, CoroutineDesugaring, CoroutineKind};
 use rustc_infer::traits::{Obligation, PolyTraitObligation, SelectionError};
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
-use rustc_middle::ty::{
-    self, SizedTraitKind, Ty, TypeFlags, TypeVisitableExt, TypingMode, elaborate,
-};
+use rustc_middle::ty::{self, SizedTraitKind, Ty, TypeVisitableExt, TypingMode, elaborate};
 use rustc_middle::{bug, span_bug};
 use tracing::{debug, instrument, trace};
 
@@ -262,11 +260,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         candidates: &mut SelectionCandidateSet<'tcx>,
     ) -> Result<(), SelectionError<'tcx>> {
         debug!(?stack.obligation);
-        if stack.obligation.param_env.has_type_flags(TypeFlags::HAS_CANONICAL_BOUND) {
-            for b in stack.obligation.param_env.caller_bounds() {
-                assert!(!b.has_type_flags(TypeFlags::HAS_CANONICAL_BOUND), "{:?} as bound vars", b);
-            }
-        }
 
         let bounds = stack
             .obligation