Rename `OpportunisticTypeResolver` to `OpportunisticVarResolver`

src/librustc/infer/error_reporting/mod.rs

@@ -652,7 +652,7 @@ fn note_error_origin(
                         for sp in prior_arms {
                             err.span_label(*sp, format!(
                                 "this is found to be of type `{}`",
-                                self.resolve_type_vars_if_possible(&last_ty),
+                                self.resolve_vars_if_possible(&last_ty),
                             ));
                         }
                     } else if let Some(sp) = prior_arms.last() {
@@ -1278,7 +1278,7 @@ fn expected_found_str_ty(
         &self,
         exp_found: &ty::error::ExpectedFound<Ty<'tcx>>,
     ) -> Option<(DiagnosticStyledString, DiagnosticStyledString)> {
-        let exp_found = self.resolve_type_vars_if_possible(exp_found);
+        let exp_found = self.resolve_vars_if_possible(exp_found);
         if exp_found.references_error() {
             return None;
         }
@@ -1291,7 +1291,7 @@ fn expected_found_str<T: fmt::Display + TypeFoldable<'tcx>>(
         &self,
         exp_found: &ty::error::ExpectedFound<T>,
     ) -> Option<(DiagnosticStyledString, DiagnosticStyledString)> {
-        let exp_found = self.resolve_type_vars_if_possible(exp_found);
+        let exp_found = self.resolve_vars_if_possible(exp_found);
         if exp_found.references_error() {
             return None;
         }

src/librustc/infer/error_reporting/need_type_info.rs

@@ -24,7 +24,7 @@ fn node_matches_type(&mut self, hir_id: HirId) -> bool {
         });
         match ty_opt {
             Some(ty) => {
-                let ty = self.infcx.resolve_type_vars_if_possible(&ty);
+                let ty = self.infcx.resolve_vars_if_possible(&ty);
                 ty.walk().any(|inner_ty| {
                     inner_ty == self.target_ty || match (&inner_ty.sty, &self.target_ty.sty) {
                         (&Infer(TyVar(a_vid)), &Infer(TyVar(b_vid))) => {
@@ -94,7 +94,7 @@ pub fn need_type_info_err(
         span: Span,
         ty: Ty<'tcx>
     ) -> DiagnosticBuilder<'gcx> {
-        let ty = self.resolve_type_vars_if_possible(&ty);
+        let ty = self.resolve_vars_if_possible(&ty);
         let name = self.extract_type_name(&ty, None);
 
         let mut err_span = span;
@@ -166,7 +166,7 @@ pub fn need_type_info_err_in_generator(
         span: Span,
         ty: Ty<'tcx>
     ) -> DiagnosticBuilder<'gcx> {
-        let ty = self.resolve_type_vars_if_possible(&ty);
+        let ty = self.resolve_vars_if_possible(&ty);
         let name = self.extract_type_name(&ty, None);
 
         let mut err = struct_span_err!(self.tcx.sess,

src/librustc/infer/error_reporting/nice_region_error/placeholder_error.rs

@@ -210,11 +210,11 @@ fn try_report_placeholders_trait(
             _ => (),
         }
 
-        let expected_trait_ref = self.infcx.resolve_type_vars_if_possible(&ty::TraitRef {
+        let expected_trait_ref = self.infcx.resolve_vars_if_possible(&ty::TraitRef {
             def_id: trait_def_id,
             substs: expected_substs,
         });
-        let actual_trait_ref = self.infcx.resolve_type_vars_if_possible(&ty::TraitRef {
+        let actual_trait_ref = self.infcx.resolve_vars_if_possible(&ty::TraitRef {
             def_id: trait_def_id,
             substs: actual_substs,
         });

src/librustc/infer/fudge.rs

@@ -74,7 +74,7 @@ pub fn fudge_inference_if_ok<T, E, F>(
         let (mut fudger, value) = self.probe(|snapshot| {
             match f() {
                 Ok(value) => {
-                    let value = self.resolve_type_vars_if_possible(&value);
+                    let value = self.resolve_vars_if_possible(&value);
 
                     // At this point, `value` could in principle refer
                     // to inference variables that have been created during

src/librustc/infer/mod.rs

@@ -1174,7 +1174,7 @@ pub fn set_tainted_by_errors(&self) {
     /// Process the region constraints and report any errors that
     /// result. After this, no more unification operations should be
     /// done -- or the compiler will panic -- but it is legal to use
-    /// `resolve_type_vars_if_possible` as well as `fully_resolve`.
+    /// `resolve_vars_if_possible` as well as `fully_resolve`.
     pub fn resolve_regions_and_report_errors(
         &self,
         region_context: DefId,
@@ -1262,7 +1262,7 @@ pub fn take_region_var_origins(&self) -> VarInfos {
     }
 
     pub fn ty_to_string(&self, t: Ty<'tcx>) -> String {
-        self.resolve_type_vars_if_possible(&t).to_string()
+        self.resolve_vars_if_possible(&t).to_string()
     }
 
     pub fn tys_to_string(&self, ts: &[Ty<'tcx>]) -> String {
@@ -1271,7 +1271,7 @@ pub fn tys_to_string(&self, ts: &[Ty<'tcx>]) -> String {
     }
 
     pub fn trait_ref_to_string(&self, t: &ty::TraitRef<'tcx>) -> String {
-        self.resolve_type_vars_if_possible(t).to_string()
+        self.resolve_vars_if_possible(t).to_string()
     }
 
     /// If `TyVar(vid)` resolves to a type, return that type. Else, return the
@@ -1297,20 +1297,20 @@ pub fn root_var(&self, var: ty::TyVid) -> ty::TyVid {
         self.type_variables.borrow_mut().root_var(var)
     }
 
-    /// Where possible, replaces type/int/float variables in
+    /// Where possible, replaces type/const variables in
     /// `value` with their final value. Note that region variables
-    /// are unaffected. If a type variable has not been unified, it
+    /// are unaffected. If a type/const variable has not been unified, it
     /// is left as is. This is an idempotent operation that does
     /// not affect inference state in any way and so you can do it
     /// at will.
-    pub fn resolve_type_vars_if_possible<T>(&self, value: &T) -> T
+    pub fn resolve_vars_if_possible<T>(&self, value: &T) -> T
     where
         T: TypeFoldable<'tcx>,
     {
         if !value.needs_infer() {
             return value.clone(); // avoid duplicated subst-folding
         }
-        let mut r = resolve::OpportunisticTypeResolver::new(self);
+        let mut r = resolve::OpportunisticVarResolver::new(self);
         value.fold_with(&mut r)
     }
 
@@ -1318,7 +1318,7 @@ pub fn resolve_type_vars_if_possible<T>(&self, value: &T) -> T
     /// process of visiting `T`, this will resolve (where possible)
     /// type variables in `T`, but it never constructs the final,
     /// resolved type, so it's more efficient than
-    /// `resolve_type_vars_if_possible()`.
+    /// `resolve_vars_if_possible()`.
     pub fn unresolved_type_vars<T>(&self, value: &T) -> Option<(Ty<'tcx>, Option<Span>)>
     where
         T: TypeFoldable<'tcx>,
@@ -1389,7 +1389,7 @@ pub fn type_error_struct_with_diag<M>(
     where
         M: FnOnce(String) -> DiagnosticBuilder<'tcx>,
     {
-        let actual_ty = self.resolve_type_vars_if_possible(&actual_ty);
+        let actual_ty = self.resolve_vars_if_possible(&actual_ty);
         debug!("type_error_struct_with_diag({:?}, {:?})", sp, actual_ty);
 
         // Don't report an error if actual type is `Error`.
@@ -1446,7 +1446,7 @@ pub fn type_is_copy_modulo_regions(
         ty: Ty<'tcx>,
         span: Span,
     ) -> bool {
-        let ty = self.resolve_type_vars_if_possible(&ty);
+        let ty = self.resolve_vars_if_possible(&ty);
 
         // Even if the type may have no inference variables, during
         // type-checking closure types are in local tables only.

src/librustc/infer/opaque_types/mod.rs

@@ -284,9 +284,7 @@ pub fn constrain_opaque_type<FRR: FreeRegionRelations<'tcx>>(
         debug!("constrain_opaque_type: def_id={:?}", def_id);
         debug!("constrain_opaque_type: opaque_defn={:#?}", opaque_defn);
 
-        let tcx = self.tcx;
-
-        let concrete_ty = self.resolve_type_vars_if_possible(&opaque_defn.concrete_ty);
+        let concrete_ty = self.resolve_vars_if_possible(&opaque_defn.concrete_ty);
 
         debug!("constrain_opaque_type: concrete_ty={:?}", concrete_ty);
 

src/librustc/infer/outlives/env.rs

@@ -168,7 +168,7 @@ pub fn add_implied_bounds(
         debug!("add_implied_bounds()");
 
         for &ty in fn_sig_tys {
-            let ty = infcx.resolve_type_vars_if_possible(&ty);
+            let ty = infcx.resolve_vars_if_possible(&ty);
             debug!("add_implied_bounds: ty = {}", ty);
             let implied_bounds = infcx.implied_outlives_bounds(self.param_env, body_id, ty, span);
             self.add_outlives_bounds(Some(infcx), implied_bounds)

src/librustc/infer/outlives/obligations.rs

@@ -177,7 +177,7 @@ pub fn process_registered_region_obligations(
                 sup_type, sub_region, origin
             );
 
-            let sup_type = self.resolve_type_vars_if_possible(&sup_type);
+            let sup_type = self.resolve_vars_if_possible(&sup_type);
 
             if let Some(region_bound_pairs) = region_bound_pairs_map.get(&body_id) {
                 let outlives = &mut TypeOutlives::new(
@@ -215,7 +215,7 @@ pub fn type_must_outlive(
             implicit_region_bound,
             param_env,
         );
-        let ty = self.resolve_type_vars_if_possible(&ty);
+        let ty = self.resolve_vars_if_possible(&ty);
         outlives.type_must_outlive(origin, ty, region);
     }
 }

src/librustc/infer/resolve.rs

@@ -4,25 +4,25 @@
 use crate::ty::fold::{TypeFolder, TypeVisitor};
 
 ///////////////////////////////////////////////////////////////////////////
-// OPPORTUNISTIC TYPE RESOLVER
+// OPPORTUNISTIC KIND RESOLVER
 
-/// The opportunistic type resolver can be used at any time. It simply replaces
-/// type variables that have been unified with the things they have
+/// The opportunistic kind resolver can be used at any time. It simply replaces
+/// type/const variables that have been unified with the things they have
 /// been unified with (similar to `shallow_resolve`, but deep). This is
 /// useful for printing messages etc but also required at various
 /// points for correctness.
-pub struct OpportunisticTypeResolver<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
+pub struct OpportunisticVarResolver<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
     infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
 }
 
-impl<'a, 'gcx, 'tcx> OpportunisticTypeResolver<'a, 'gcx, 'tcx> {
+impl<'a, 'gcx, 'tcx> OpportunisticVarResolver<'a, 'gcx, 'tcx> {
     #[inline]
     pub fn new(infcx: &'a InferCtxt<'a, 'gcx, 'tcx>) -> Self {
-        OpportunisticTypeResolver { infcx }
+        OpportunisticVarResolver { infcx }
     }
 }
 
-impl<'a, 'gcx, 'tcx> TypeFolder<'gcx, 'tcx> for OpportunisticTypeResolver<'a, 'gcx, 'tcx> {
+impl<'a, 'gcx, 'tcx> TypeFolder<'gcx, 'tcx> for OpportunisticVarResolver<'a, 'gcx, 'tcx> {
     fn tcx<'b>(&'b self) -> TyCtxt<'b, 'gcx, 'tcx> {
         self.infcx.tcx
     }

src/librustc/middle/mem_categorization.rs

@@ -458,10 +458,10 @@ pub fn type_is_copy_modulo_regions(
             .unwrap_or(true)
     }
 
-    fn resolve_type_vars_if_possible<T>(&self, value: &T) -> T
+    fn resolve_vars_if_possible<T>(&self, value: &T) -> T
         where T: TypeFoldable<'tcx>
     {
-        self.infcx.map(|infcx| infcx.resolve_type_vars_if_possible(value))
+        self.infcx.map(|infcx| infcx.resolve_vars_if_possible(value))
             .unwrap_or_else(|| value.clone())
     }
 
@@ -475,7 +475,7 @@ fn resolve_type_vars_or_error(&self,
                                   -> McResult<Ty<'tcx>> {
         match ty {
             Some(ty) => {
-                let ty = self.resolve_type_vars_if_possible(&ty);
+                let ty = self.resolve_vars_if_possible(&ty);
                 if ty.references_error() || ty.is_ty_var() {
                     debug!("resolve_type_vars_or_error: error from {:?}", ty);
                     Err(())
@@ -602,7 +602,7 @@ fn cat_expr_adjusted_with<F>(&self, expr: &hir::Expr,
         where F: FnOnce() -> McResult<cmt_<'tcx>>
     {
         debug!("cat_expr_adjusted_with({:?}): {:?}", adjustment, expr);
-        let target = self.resolve_type_vars_if_possible(&adjustment.target);
+        let target = self.resolve_vars_if_possible(&adjustment.target);
         match adjustment.kind {
             adjustment::Adjust::Deref(overloaded) => {
                 // Equivalent to *expr or something similar.

src/librustc/traits/auto_trait.rs

@@ -307,9 +307,9 @@ fn evaluate_predicates<'b, 'gcx, 'c>(
                 continue;
             }
 
-            // Call infcx.resolve_type_vars_if_possible to see if we can
+            // Call infcx.resolve_vars_if_possible to see if we can
             // get rid of any inference variables.
-            let obligation = infcx.resolve_type_vars_if_possible(
+            let obligation = infcx.resolve_vars_if_possible(
                 &Obligation::new(dummy_cause.clone(), new_env, pred)
             );
             let result = select.select(&obligation);
@@ -642,7 +642,7 @@ fn evaluate_nested_obligations<
                 fresh_preds.insert(self.clean_pred(select.infcx(), predicate));
 
             // Resolve any inference variables that we can, to help selection succeed
-            predicate = select.infcx().resolve_type_vars_if_possible(&predicate);
+            predicate = select.infcx().resolve_vars_if_possible(&predicate);
 
             // We only add a predicate as a user-displayable bound if
             // it involves a generic parameter, and doesn't contain

src/librustc/traits/chalk_fulfill.rs

@@ -33,7 +33,7 @@ fn in_environment(
     obligation: PredicateObligation<'tcx>
 ) -> InEnvironment<'tcx, PredicateObligation<'tcx>> {
     assert!(!infcx.is_in_snapshot());
-    let obligation = infcx.resolve_type_vars_if_possible(&obligation);
+    let obligation = infcx.resolve_vars_if_possible(&obligation);
 
     let environment = match obligation.param_env.def_id {
         Some(def_id) => infcx.tcx.environment(def_id),

src/librustc/traits/codegen/mod.rs

@@ -153,7 +153,7 @@ fn drain_fulfillment_cx_or_panic<T>(&self,
             bug!("Encountered errors `{:?}` resolving bounds after type-checking", errors);
         }
 
-        let result = self.resolve_type_vars_if_possible(result);
+        let result = self.resolve_vars_if_possible(result);
         let result = self.tcx.erase_regions(&result);
 
         self.tcx.lift_to_global(&result).unwrap_or_else(||

src/librustc/traits/coherence.rs

@@ -155,7 +155,7 @@ fn overlap_within_probe(
         a_impl_header.predicates
                      .iter()
                      .chain(&b_impl_header.predicates)
-                     .map(|p| infcx.resolve_type_vars_if_possible(p))
+                     .map(|p| infcx.resolve_vars_if_possible(p))
                      .map(|p| Obligation { cause: ObligationCause::dummy(),
                                            param_env,
                                            recursion_depth: 0,
@@ -171,7 +171,7 @@ fn overlap_within_probe(
         return None
     }
 
-    let impl_header = selcx.infcx().resolve_type_vars_if_possible(&a_impl_header);
+    let impl_header = selcx.infcx().resolve_vars_if_possible(&a_impl_header);
     let intercrate_ambiguity_causes = selcx.take_intercrate_ambiguity_causes();
     debug!("overlap: intercrate_ambiguity_causes={:#?}", intercrate_ambiguity_causes);
 

src/librustc/traits/error_reporting.rs

@@ -186,7 +186,7 @@ fn report_projection_error(&self,
                                error: &MismatchedProjectionTypes<'tcx>)
     {
         let predicate =
-            self.resolve_type_vars_if_possible(&obligation.predicate);
+            self.resolve_vars_if_possible(&obligation.predicate);
 
         if predicate.references_error() {
             return
@@ -531,7 +531,7 @@ pub fn report_overflow_error<T>(&self,
         where T: fmt::Display + TypeFoldable<'tcx>
     {
         let predicate =
-            self.resolve_type_vars_if_possible(&obligation.predicate);
+            self.resolve_vars_if_possible(&obligation.predicate);
         let mut err = struct_span_err!(self.tcx.sess, obligation.cause.span, E0275,
                                        "overflow evaluating the requirement `{}`",
                                        predicate);
@@ -553,7 +553,7 @@ pub fn report_overflow_error<T>(&self,
     /// we do not suggest increasing the overflow limit, which is not
     /// going to help).
     pub fn report_overflow_error_cycle(&self, cycle: &[PredicateObligation<'tcx>]) -> ! {
-        let cycle = self.resolve_type_vars_if_possible(&cycle.to_owned());
+        let cycle = self.resolve_vars_if_possible(&cycle.to_owned());
         assert!(cycle.len() > 0);
 
         debug!("report_overflow_error_cycle: cycle={:?}", cycle);
@@ -589,7 +589,7 @@ pub fn report_extra_impl_obligation(&self,
     fn get_parent_trait_ref(&self, code: &ObligationCauseCode<'tcx>) -> Option<String> {
         match code {
             &ObligationCauseCode::BuiltinDerivedObligation(ref data) => {
-                let parent_trait_ref = self.resolve_type_vars_if_possible(
+                let parent_trait_ref = self.resolve_vars_if_possible(
                     &data.parent_trait_ref);
                 match self.get_parent_trait_ref(&data.parent_code) {
                     Some(t) => Some(t),
@@ -625,7 +625,7 @@ pub fn report_selection_error(
                 match obligation.predicate {
                     ty::Predicate::Trait(ref trait_predicate) => {
                         let trait_predicate =
-                            self.resolve_type_vars_if_possible(trait_predicate);
+                            self.resolve_vars_if_possible(trait_predicate);
 
                         if self.tcx.sess.has_errors() && trait_predicate.references_error() {
                             return;
@@ -749,7 +749,7 @@ pub fn report_selection_error(
                     }
 
                     ty::Predicate::RegionOutlives(ref predicate) => {
-                        let predicate = self.resolve_type_vars_if_possible(predicate);
+                        let predicate = self.resolve_vars_if_possible(predicate);
                         let err = self.region_outlives_predicate(&obligation.cause,
                                                                  &predicate).err().unwrap();
                         struct_span_err!(
@@ -761,7 +761,7 @@ pub fn report_selection_error(
 
                     ty::Predicate::Projection(..) | ty::Predicate::TypeOutlives(..) => {
                         let predicate =
-                            self.resolve_type_vars_if_possible(&obligation.predicate);
+                            self.resolve_vars_if_possible(&obligation.predicate);
                         struct_span_err!(self.tcx.sess, span, E0280,
                             "the requirement `{}` is not satisfied",
                             predicate)
@@ -852,8 +852,8 @@ pub fn report_selection_error(
             }
 
             OutputTypeParameterMismatch(ref found_trait_ref, ref expected_trait_ref, _) => {
-                let found_trait_ref = self.resolve_type_vars_if_possible(&*found_trait_ref);
-                let expected_trait_ref = self.resolve_type_vars_if_possible(&*expected_trait_ref);
+                let found_trait_ref = self.resolve_vars_if_possible(&*found_trait_ref);
+                let expected_trait_ref = self.resolve_vars_if_possible(&*expected_trait_ref);
 
                 if expected_trait_ref.self_ty().references_error() {
                     return;
@@ -1345,7 +1345,7 @@ fn maybe_report_ambiguity(&self, obligation: &PredicateObligation<'tcx>,
         // ambiguous impls. The latter *ought* to be a
         // coherence violation, so we don't report it here.
 
-        let predicate = self.resolve_type_vars_if_possible(&obligation.predicate);
+        let predicate = self.resolve_vars_if_possible(&obligation.predicate);
         let span = obligation.cause.span;
 
         debug!("maybe_report_ambiguity(predicate={:?}, obligation={:?})",
@@ -1617,7 +1617,7 @@ fn note_obligation_cause_code<T>(&self,
                 err.note("shared static variables must have a type that implements `Sync`");
             }
             ObligationCauseCode::BuiltinDerivedObligation(ref data) => {
-                let parent_trait_ref = self.resolve_type_vars_if_possible(&data.parent_trait_ref);
+                let parent_trait_ref = self.resolve_vars_if_possible(&data.parent_trait_ref);
                 let ty = parent_trait_ref.skip_binder().self_ty();
                 err.note(&format!("required because it appears within the type `{}`", ty));
                 obligated_types.push(ty);
@@ -1631,7 +1631,7 @@ fn note_obligation_cause_code<T>(&self,
                 }
             }
             ObligationCauseCode::ImplDerivedObligation(ref data) => {
-                let parent_trait_ref = self.resolve_type_vars_if_possible(&data.parent_trait_ref);
+                let parent_trait_ref = self.resolve_vars_if_possible(&data.parent_trait_ref);
                 err.note(
                     &format!("required because of the requirements on the impl of `{}` for `{}`",
                              parent_trait_ref,
@@ -1672,7 +1672,7 @@ fn is_recursive_obligation(&self,
                                obligated_types: &mut Vec<&ty::TyS<'tcx>>,
                                cause_code: &ObligationCauseCode<'tcx>) -> bool {
         if let ObligationCauseCode::BuiltinDerivedObligation(ref data) = cause_code {
-            let parent_trait_ref = self.resolve_type_vars_if_possible(&data.parent_trait_ref);
+            let parent_trait_ref = self.resolve_vars_if_possible(&data.parent_trait_ref);
 
             if obligated_types.iter().any(|ot| ot == &parent_trait_ref.skip_binder().self_ty()) {
                 return true;

src/librustc/traits/fulfill.rs

@@ -178,7 +178,7 @@ fn register_predicate_obligation<'a, 'gcx>(&mut self,
     {
         // this helps to reduce duplicate errors, as well as making
         // debug output much nicer to read and so on.
-        let obligation = infcx.resolve_type_vars_if_possible(&obligation);
+        let obligation = infcx.resolve_vars_if_possible(&obligation);
 
         debug!("register_predicate_obligation(obligation={:?})", obligation);
 
@@ -261,7 +261,7 @@ fn process_obligation(&mut self,
             }) {
                 debug!("process_predicate: pending obligation {:?} still stalled on {:?}",
                        self.selcx.infcx()
-                           .resolve_type_vars_if_possible(&pending_obligation.obligation),
+                           .resolve_vars_if_possible(&pending_obligation.obligation),
                        pending_obligation.stalled_on);
                 return ProcessResult::Unchanged;
             }
@@ -272,7 +272,7 @@ fn process_obligation(&mut self,
 
         if obligation.predicate.has_infer_types() {
             obligation.predicate =
-                self.selcx.infcx().resolve_type_vars_if_possible(&obligation.predicate);
+                self.selcx.infcx().resolve_vars_if_possible(&obligation.predicate);
         }
 
         debug!("process_obligation: obligation = {:?}", obligation);
@@ -318,7 +318,7 @@ fn process_obligation(&mut self,
                             trait_ref_type_vars(self.selcx, data.to_poly_trait_ref());
 
                         debug!("process_predicate: pending obligation {:?} now stalled on {:?}",
-                               self.selcx.infcx().resolve_type_vars_if_possible(obligation),
+                               self.selcx.infcx().resolve_vars_if_possible(obligation),
                                pending_obligation.stalled_on);
 
                         ProcessResult::Unchanged
@@ -519,7 +519,7 @@ fn trait_ref_type_vars<'a, 'gcx, 'tcx>(selcx: &mut SelectionContext<'a, 'gcx, 't
 {
     t.skip_binder() // ok b/c this check doesn't care about regions
      .input_types()
-     .map(|t| selcx.infcx().resolve_type_vars_if_possible(&t))
+     .map(|t| selcx.infcx().resolve_vars_if_possible(&t))
      .filter(|t| t.has_infer_types())
      .flat_map(|t| t.walk())
      .filter(|t| match t.sty { ty::Infer(_) => true, _ => false })

src/librustc/traits/mod.rs

@@ -927,7 +927,7 @@ pub fn fully_normalize<'a, 'gcx, 'tcx, T>(
     debug!("fully_normalize: select_all_or_error start");
     fulfill_cx.select_all_or_error(infcx)?;
     debug!("fully_normalize: select_all_or_error complete");
-    let resolved_value = infcx.resolve_type_vars_if_possible(&normalized_value);
+    let resolved_value = infcx.resolve_vars_if_possible(&normalized_value);
     debug!("fully_normalize: resolved_value={:?}", resolved_value);
     Ok(resolved_value)
 }

src/librustc/traits/project.rs

@@ -312,7 +312,7 @@ fn new(selcx: &'a mut SelectionContext<'b, 'gcx, 'tcx>,
     }
 
     fn fold<T:TypeFoldable<'tcx>>(&mut self, value: &T) -> T {
-        let value = self.selcx.infcx().resolve_type_vars_if_possible(value);
+        let value = self.selcx.infcx().resolve_vars_if_possible(value);
 
         if !value.has_projections() {
             value
@@ -508,7 +508,7 @@ fn opt_normalize_projection_type<'a, 'b, 'gcx, 'tcx>(
 {
     let infcx = selcx.infcx();
 
-    let projection_ty = infcx.resolve_type_vars_if_possible(&projection_ty);
+    let projection_ty = infcx.resolve_vars_if_possible(&projection_ty);
     let cache_key = ProjectionCacheKey { ty: projection_ty };
 
     debug!("opt_normalize_projection_type(\
@@ -1614,7 +1614,7 @@ pub fn from_poly_projection_predicate(selcx: &mut SelectionContext<'cx, 'gcx, 't
                 // from a specific call to `opt_normalize_projection_type` - if
                 // there's no precise match, the original cache entry is "stranded"
                 // anyway.
-                ty: infcx.resolve_type_vars_if_possible(&predicate.projection_ty)
+                ty: infcx.resolve_vars_if_possible(&predicate.projection_ty)
             })
     }
 }

src/librustc/traits/query/dropck_outlives.rs

@@ -54,7 +54,7 @@ pub fn dropck_outlives(&self, ty: Ty<'tcx>) -> InferOk<'tcx, Vec<Kind<'tcx>>> {
                     &orig_values,
                     result)
                 {
-                    let ty = self.infcx.resolve_type_vars_if_possible(&ty);
+                    let ty = self.infcx.resolve_vars_if_possible(&ty);
                     let kinds = value.into_kinds_reporting_overflows(tcx, span, ty);
                     return InferOk {
                         value: kinds,

src/librustc/traits/query/type_op/custom.rs

@@ -97,7 +97,7 @@ fn scrape_region_constraints<'gcx, 'tcx, R>(
         region_obligations
             .iter()
             .map(|(_, r_o)| (r_o.sup_type, r_o.sub_region))
-            .map(|(ty, r)| (infcx.resolve_type_vars_if_possible(&ty), r)),
+            .map(|(ty, r)| (infcx.resolve_vars_if_possible(&ty), r)),
         &region_constraint_data,
     );
 

src/librustc/traits/select.rs

@@ -1463,7 +1463,7 @@ fn is_knowable<'o>(&mut self, stack: &TraitObligationStack<'o, 'tcx>) -> Option<
 
         let obligation = &stack.obligation;
         let predicate = self.infcx()
-            .resolve_type_vars_if_possible(&obligation.predicate);
+            .resolve_vars_if_possible(&obligation.predicate);
 
         // OK to skip binder because of the nature of the
         // trait-ref-is-knowable check, which does not care about
@@ -1621,7 +1621,7 @@ fn assemble_candidates<'o>(
             cause: obligation.cause.clone(),
             recursion_depth: obligation.recursion_depth,
             predicate: self.infcx()
-                .resolve_type_vars_if_possible(&obligation.predicate),
+                .resolve_vars_if_possible(&obligation.predicate),
         };
 
         if obligation.predicate.skip_binder().self_ty().is_ty_var() {
@@ -1737,7 +1737,7 @@ fn match_projection_obligation_against_definition_bounds(
         snapshot: &CombinedSnapshot<'_, 'tcx>,
     ) -> bool {
         let poly_trait_predicate = self.infcx()
-            .resolve_type_vars_if_possible(&obligation.predicate);
+            .resolve_vars_if_possible(&obligation.predicate);
         let (placeholder_trait_predicate, placeholder_map) = self.infcx()
             .replace_bound_vars_with_placeholders(&poly_trait_predicate);
         debug!(

src/librustc/traits/specialize/mod.rs

@@ -278,7 +278,7 @@ fn fulfill_implication<'a, 'gcx, 'tcx>(infcx: &InferCtxt<'a, 'gcx, 'tcx>,
 
                 // Now resolve the *substitution* we built for the target earlier, replacing
                 // the inference variables inside with whatever we got from fulfillment.
-                Ok(infcx.resolve_type_vars_if_possible(&target_substs))
+                Ok(infcx.resolve_vars_if_possible(&target_substs))
             }
         }
     })

src/librustc_mir/borrow_check/nll/type_check/mod.rs

@@ -1263,7 +1263,7 @@ fn eq_opaque_type_and_type(
                         debug!(
                             "eq_opaque_type_and_type: concrete_ty={:?}={:?} opaque_defn_ty={:?}",
                             opaque_decl.concrete_ty,
-                            infcx.resolve_type_vars_if_possible(&opaque_decl.concrete_ty),
+                            infcx.resolve_vars_if_possible(&opaque_decl.concrete_ty),
                             opaque_defn_ty
                         );
                         obligations.add(infcx

src/librustc_traits/chalk_context/mod.rs

@@ -411,7 +411,7 @@ fn instantiate_binders_existentially(
     }
 
     fn debug_ex_clause(&mut self, value: &'v ChalkExClause<'tcx>) -> Box<dyn Debug + 'v> {
-        let string = format!("{:?}", self.infcx.resolve_type_vars_if_possible(value));
+        let string = format!("{:?}", self.infcx.resolve_vars_if_possible(value));
         Box::new(string)
     }
 

src/librustc_traits/chalk_context/program_clauses/mod.rs

@@ -57,7 +57,7 @@ pub(super) fn program_clauses_impl(
         use rustc::traits::WhereClause::*;
         use rustc::infer::canonical::OriginalQueryValues;
 
-        let goal = self.infcx.resolve_type_vars_if_possible(goal);
+        let goal = self.infcx.resolve_vars_if_possible(goal);
 
         debug!("program_clauses(goal = {:?})", goal);
 

src/librustc_traits/chalk_context/resolvent_ops.rs

@@ -111,8 +111,8 @@ fn apply_answer_subst(
     ) -> Fallible<ChalkExClause<'tcx>> {
         debug!(
             "apply_answer_subst(ex_clause = {:?}, selected_goal = {:?})",
-            self.infcx.resolve_type_vars_if_possible(&ex_clause),
-            self.infcx.resolve_type_vars_if_possible(selected_goal)
+            self.infcx.resolve_vars_if_possible(&ex_clause),
+            self.infcx.resolve_vars_if_possible(selected_goal)
         );
 
         let (answer_subst, _) = self.infcx.instantiate_canonical_with_fresh_inference_vars(

src/librustc_traits/implied_outlives_bounds.rs

@@ -121,7 +121,7 @@ fn compute_implied_outlives_bounds<'tcx>(
                 ty::Predicate::TypeOutlives(ref data) => match data.no_bound_vars() {
                     None => vec![],
                     Some(ty::OutlivesPredicate(ty_a, r_b)) => {
-                        let ty_a = infcx.resolve_type_vars_if_possible(&ty_a);
+                        let ty_a = infcx.resolve_vars_if_possible(&ty_a);
                         let mut components = smallvec![];
                         tcx.push_outlives_components(ty_a, &mut components);
                         implied_bounds_from_components(r_b, components)

src/librustc_traits/normalize_erasing_regions.rs

@@ -36,7 +36,7 @@ fn normalize_ty_after_erasing_regions<'tcx>(
                     None,
                 );
 
-                let normalized_value = infcx.resolve_type_vars_if_possible(&normalized_value);
+                let normalized_value = infcx.resolve_vars_if_possible(&normalized_value);
                 let normalized_value = infcx.tcx.erase_regions(&normalized_value);
                 tcx.lift_to_global(&normalized_value).unwrap()
             }

src/librustc_typeck/check/_match.rs

@@ -226,7 +226,7 @@ pub fn check_pat_walk(
 
                 // Now that we know the types can be unified we find the unified type and use
                 // it to type the entire expression.
-                let common_type = self.resolve_type_vars_if_possible(&lhs_ty);
+                let common_type = self.resolve_vars_if_possible(&lhs_ty);
 
                 // subtyping doesn't matter here, as the value is some kind of scalar
                 self.demand_eqtype_pat(pat.span, expected, lhs_ty, discrim_span);

src/librustc_typeck/check/autoderef.rs

@@ -98,7 +98,7 @@ pub fn new(infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
             body_id,
             param_env,
             steps: vec![],
-            cur_ty: infcx.resolve_type_vars_if_possible(&base_ty),
+            cur_ty: infcx.resolve_vars_if_possible(&base_ty),
             obligations: vec![],
             at_start: true,
             include_raw_pointers: false,
@@ -152,7 +152,7 @@ fn overloaded_deref_ty(&mut self, ty: Ty<'tcx>) -> Option<Ty<'tcx>> {
                ty, normalized_ty, obligations);
         self.obligations.extend(obligations);
 
-        Some(self.infcx.resolve_type_vars_if_possible(&normalized_ty))
+        Some(self.infcx.resolve_vars_if_possible(&normalized_ty))
     }
 
     /// Returns the final type, generating an error if it is an
@@ -164,7 +164,7 @@ pub fn unambiguous_final_ty(&self, fcx: &FnCtxt<'a, 'gcx, 'tcx>) -> Ty<'tcx> {
     /// Returns the final type we ended up with, which may well be an
     /// inference variable (we will resolve it first, if possible).
     pub fn maybe_ambiguous_final_ty(&self) -> Ty<'tcx> {
-        self.infcx.resolve_type_vars_if_possible(&self.cur_ty)
+        self.infcx.resolve_vars_if_possible(&self.cur_ty)
     }
 
     pub fn step_count(&self) -> usize {

src/librustc_typeck/check/cast.rs

@@ -82,7 +82,7 @@ fn pointer_kind(&self, t: Ty<'tcx>, span: Span) ->
     {
         debug!("pointer_kind({:?}, {:?})", t, span);
 
-        let t = self.resolve_type_vars_if_possible(&t);
+        let t = self.resolve_vars_if_possible(&t);
 
         if t.references_error() {
             return Err(ErrorReported);
@@ -334,7 +334,7 @@ fn report_cast_to_unsized_type(&self, fcx: &FnCtxt<'a, 'gcx, 'tcx>) {
         let tstr = fcx.ty_to_string(self.cast_ty);
         let mut err = type_error_struct!(fcx.tcx.sess, self.span, self.expr_ty, E0620,
                                          "cast to unsized type: `{}` as `{}`",
-                                         fcx.resolve_type_vars_if_possible(&self.expr_ty),
+                                         fcx.resolve_vars_if_possible(&self.expr_ty),
                                          tstr);
         match self.expr_ty.sty {
             ty::Ref(_, _, mt) => {

src/librustc_typeck/check/closure.rs

@@ -282,7 +282,7 @@ fn deduce_sig_from_projection(
 
         let input_tys = if is_fn {
             let arg_param_ty = trait_ref.skip_binder().substs.type_at(1);
-            let arg_param_ty = self.resolve_type_vars_if_possible(&arg_param_ty);
+            let arg_param_ty = self.resolve_vars_if_possible(&arg_param_ty);
             debug!("deduce_sig_from_projection: arg_param_ty={:?}", arg_param_ty);
 
             match arg_param_ty.sty {
@@ -295,7 +295,7 @@ fn deduce_sig_from_projection(
         };
 
         let ret_param_ty = projection.skip_binder().ty;
-        let ret_param_ty = self.resolve_type_vars_if_possible(&ret_param_ty);
+        let ret_param_ty = self.resolve_vars_if_possible(&ret_param_ty);
         debug!("deduce_sig_from_projection: ret_param_ty={:?}", ret_param_ty);
 
         let sig = self.tcx.mk_fn_sig(

src/librustc_typeck/check/coercion.rs

@@ -575,7 +575,7 @@ fn coerce_unsized(&self, source: Ty<'tcx>, target: Ty<'tcx>) -> CoerceResult<'tc
                 // Uncertain or unimplemented.
                 Ok(None) => {
                     if trait_ref.def_id() == unsize_did {
-                        let trait_ref = self.resolve_type_vars_if_possible(&trait_ref);
+                        let trait_ref = self.resolve_vars_if_possible(&trait_ref);
                         let self_ty = trait_ref.skip_binder().self_ty();
                         let unsize_ty = trait_ref.skip_binder().input_types().nth(1).unwrap();
                         debug!("coerce_unsized: ambiguous unsize case for {:?}", trait_ref);

src/librustc_typeck/check/generator_interior.rs

@@ -48,7 +48,7 @@ fn record(&mut self,
         });
 
         if let Some(yield_span) = live_across_yield {
-            let ty = self.fcx.resolve_type_vars_if_possible(&ty);
+            let ty = self.fcx.resolve_vars_if_possible(&ty);
 
             debug!("type in expr = {:?}, scope = {:?}, type = {:?}, count = {}, yield_span = {:?}",
                    expr, scope, ty, self.expr_count, yield_span);

src/librustc_typeck/check/method/confirm.rs

@@ -511,7 +511,7 @@ fn convert_place_op_to_mutable(&self,
 
         let base_ty = self.tables.borrow().expr_adjustments(base_expr).last()
             .map_or_else(|| self.node_ty(expr.hir_id), |adj| adj.target);
-        let base_ty = self.resolve_type_vars_if_possible(&base_ty);
+        let base_ty = self.resolve_vars_if_possible(&base_ty);
 
         // Need to deref because overloaded place ops take self by-reference.
         let base_ty = base_ty.builtin_deref(false)

src/librustc_typeck/check/method/mod.rs

@@ -253,7 +253,7 @@ fn lookup_probe(&self,
                     scope: ProbeScope)
                     -> probe::PickResult<'tcx> {
         let mode = probe::Mode::MethodCall;
-        let self_ty = self.resolve_type_vars_if_possible(&self_ty);
+        let self_ty = self.resolve_vars_if_possible(&self_ty);
         self.probe_for_name(span, mode, method_name, IsSuggestion(false),
                             self_ty, call_expr.hir_id, scope)
     }

src/librustc_typeck/check/method/probe.rs

@@ -1338,7 +1338,7 @@ fn consider_probe(&self,
                             // and point at it rather than reporting the entire
                             // trait-ref?
                             result = ProbeResult::NoMatch;
-                            let trait_ref = self.resolve_type_vars_if_possible(&trait_ref);
+                            let trait_ref = self.resolve_vars_if_possible(&trait_ref);
                             possibly_unsatisfied_predicates.push(trait_ref);
                         }
                     }
@@ -1351,7 +1351,7 @@ fn consider_probe(&self,
 
             // Evaluate those obligations to see if they might possibly hold.
             for o in candidate_obligations.into_iter().chain(sub_obligations) {
-                let o = self.resolve_type_vars_if_possible(&o);
+                let o = self.resolve_vars_if_possible(&o);
                 if !self.predicate_may_hold(&o) {
                     result = ProbeResult::NoMatch;
                     if let &ty::Predicate::Trait(ref pred) = &o.predicate {
@@ -1364,7 +1364,7 @@ fn consider_probe(&self,
                 if let (Some(return_ty), Some(xform_ret_ty)) =
                     (self.return_type, probe.xform_ret_ty)
                 {
-                    let xform_ret_ty = self.resolve_type_vars_if_possible(&xform_ret_ty);
+                    let xform_ret_ty = self.resolve_vars_if_possible(&xform_ret_ty);
                     debug!("comparing return_ty {:?} with xform ret ty {:?}",
                            return_ty,
                            probe.xform_ret_ty);

src/librustc_typeck/check/method/suggest.rs

@@ -196,7 +196,7 @@ pub fn report_method_error<'b>(
             }) => {
                 let tcx = self.tcx;
 
-                let actual = self.resolve_type_vars_if_possible(&rcvr_ty);
+                let actual = self.resolve_vars_if_possible(&rcvr_ty);
                 let ty_str = self.ty_to_string(actual);
                 let is_method = mode == Mode::MethodCall;
                 let item_kind = if is_method {

src/librustc_typeck/check/mod.rs

@@ -330,13 +330,13 @@ fn resolve(self, fcx: &FnCtxt<'a, 'gcx, 'tcx>) -> Expectation<'tcx> {
         match self {
             NoExpectation => NoExpectation,
             ExpectCastableToType(t) => {
-                ExpectCastableToType(fcx.resolve_type_vars_if_possible(&t))
+                ExpectCastableToType(fcx.resolve_vars_if_possible(&t))
             }
             ExpectHasType(t) => {
-                ExpectHasType(fcx.resolve_type_vars_if_possible(&t))
+                ExpectHasType(fcx.resolve_vars_if_possible(&t))
             }
             ExpectRvalueLikeUnsized(t) => {
-                ExpectRvalueLikeUnsized(fcx.resolve_type_vars_if_possible(&t))
+                ExpectRvalueLikeUnsized(fcx.resolve_vars_if_possible(&t))
             }
         }
     }
@@ -2067,7 +2067,7 @@ pub fn misc(&self, span: Span) -> ObligationCause<'tcx> {
     }
 
     /// Resolves type variables in `ty` if possible. Unlike the infcx
-    /// version (resolve_type_vars_if_possible), this version will
+    /// version (resolve_vars_if_possible), this version will
     /// also select obligations if it seems useful, in an effort
     /// to get more type information.
     fn resolve_type_vars_with_obligations(&self, mut ty: Ty<'tcx>) -> Ty<'tcx> {
@@ -2080,7 +2080,7 @@ fn resolve_type_vars_with_obligations(&self, mut ty: Ty<'tcx>) -> Ty<'tcx> {
         }
 
         // If `ty` is a type variable, see whether we already know what it is.
-        ty = self.resolve_type_vars_if_possible(&ty);
+        ty = self.resolve_vars_if_possible(&ty);
         if !ty.has_infer_types() {
             debug!("resolve_type_vars_with_obligations: ty={:?}", ty);
             return ty;
@@ -2091,7 +2091,7 @@ fn resolve_type_vars_with_obligations(&self, mut ty: Ty<'tcx>) -> Ty<'tcx> {
         // indirect dependencies that don't seem worth tracking
         // precisely.
         self.select_obligations_where_possible(false);
-        ty = self.resolve_type_vars_if_possible(&ty);
+        ty = self.resolve_vars_if_possible(&ty);
 
         debug!("resolve_type_vars_with_obligations: ty={:?}", ty);
         ty
@@ -2127,7 +2127,7 @@ pub fn local_ty(&self, span: Span, nid: hir::HirId) -> LocalTy<'tcx> {
     #[inline]
     pub fn write_ty(&self, id: hir::HirId, ty: Ty<'tcx>) {
         debug!("write_ty({:?}, {:?}) in fcx {}",
-               id, self.resolve_type_vars_if_possible(&ty), self.tag());
+               id, self.resolve_vars_if_possible(&ty), self.tag());
         self.tables.borrow_mut().node_types_mut().insert(id, ty);
 
         if ty.references_error() {
@@ -2950,9 +2950,9 @@ fn check_argument_types(&self,
         } else {
             // is the missing argument of type `()`?
             let sugg_unit = if expected_arg_tys.len() == 1 && supplied_arg_count == 0 {
-                self.resolve_type_vars_if_possible(&expected_arg_tys[0]).is_unit()
+                self.resolve_vars_if_possible(&expected_arg_tys[0]).is_unit()
             } else if fn_inputs.len() == 1 && supplied_arg_count == 0 {
-                self.resolve_type_vars_if_possible(&fn_inputs[0]).is_unit()
+                self.resolve_vars_if_possible(&fn_inputs[0]).is_unit()
             } else {
                 false
             };
@@ -3063,7 +3063,7 @@ fn variadic_error<'tcx>(s: &Session, span: Span, t: Ty<'tcx>, cast_ty: &str) {
                     }
                     ty::FnDef(..) => {
                         let ptr_ty = self.tcx.mk_fn_ptr(arg_ty.fn_sig(self.tcx));
-                        let ptr_ty = self.resolve_type_vars_if_possible(&ptr_ty);
+                        let ptr_ty = self.resolve_vars_if_possible(&ptr_ty);
                         variadic_error(tcx.sess, arg.span, arg_ty, &ptr_ty.to_string());
                     }
                     _ => {}
@@ -3253,7 +3253,7 @@ fn expected_inputs_for_expected_output(&self,
             // Record all the argument types, with the substitutions
             // produced from the above subtyping unification.
             Ok(formal_args.iter().map(|ty| {
-                self.resolve_type_vars_if_possible(ty)
+                self.resolve_vars_if_possible(ty)
             }).collect())
         }).unwrap_or_default();
         debug!("expected_inputs_for_expected_output(formal={:?} -> {:?}, expected={:?} -> {:?})",
@@ -4333,9 +4333,9 @@ fn check_expr_kind(
                 // Find the type of `e`. Supply hints based on the type we are casting to,
                 // if appropriate.
                 let t_cast = self.to_ty_saving_user_provided_ty(t);
-                let t_cast = self.resolve_type_vars_if_possible(&t_cast);
+                let t_cast = self.resolve_vars_if_possible(&t_cast);
                 let t_expr = self.check_expr_with_expectation(e, ExpectCastableToType(t_cast));
-                let t_cast = self.resolve_type_vars_if_possible(&t_cast);
+                let t_cast = self.resolve_vars_if_possible(&t_cast);
 
                 // Eagerly check for some obvious errors.
                 if t_expr.references_error() || t_cast.references_error() {

src/librustc_typeck/check/op.rs

@@ -618,7 +618,7 @@ pub fn check_user_unop(&self,
                 method.sig.output()
             }
             Err(()) => {
-                let actual = self.resolve_type_vars_if_possible(&operand_ty);
+                let actual = self.resolve_vars_if_possible(&operand_ty);
                 if !actual.references_error() {
                     let mut err = struct_span_err!(self.tcx.sess, ex.span, E0600,
                                      "cannot apply unary operator `{}` to type `{}`",

src/librustc_typeck/check/regionck.rs

@@ -270,7 +270,7 @@ fn set_repeating_scope(&mut self, scope: hir::HirId) -> hir::HirId {
     /// of b will be `&<R0>.i32` and then `*b` will require that `<R0>` be bigger than the let and
     /// the `*b` expression, so we will effectively resolve `<R0>` to be the block B.
     pub fn resolve_type(&self, unresolved_ty: Ty<'tcx>) -> Ty<'tcx> {
-        self.resolve_type_vars_if_possible(&unresolved_ty)
+        self.resolve_vars_if_possible(&unresolved_ty)
     }
 
     /// Try to resolve the type for the given node.

src/librustc_typeck/check/writeback.rs

@@ -138,7 +138,7 @@ fn fix_scalar_builtin_expr(&mut self, e: &hir::Expr) {
             hir::ExprKind::Unary(hir::UnNeg, ref inner)
             | hir::ExprKind::Unary(hir::UnNot, ref inner) => {
                 let inner_ty = self.fcx.node_ty(inner.hir_id);
-                let inner_ty = self.fcx.resolve_type_vars_if_possible(&inner_ty);
+                let inner_ty = self.fcx.resolve_vars_if_possible(&inner_ty);
 
                 if inner_ty.is_scalar() {
                     let mut tables = self.fcx.tables.borrow_mut();
@@ -149,10 +149,10 @@ fn fix_scalar_builtin_expr(&mut self, e: &hir::Expr) {
             hir::ExprKind::Binary(ref op, ref lhs, ref rhs)
             | hir::ExprKind::AssignOp(ref op, ref lhs, ref rhs) => {
                 let lhs_ty = self.fcx.node_ty(lhs.hir_id);
-                let lhs_ty = self.fcx.resolve_type_vars_if_possible(&lhs_ty);
+                let lhs_ty = self.fcx.resolve_vars_if_possible(&lhs_ty);
 
                 let rhs_ty = self.fcx.node_ty(rhs.hir_id);
-                let rhs_ty = self.fcx.resolve_type_vars_if_possible(&rhs_ty);
+                let rhs_ty = self.fcx.resolve_vars_if_possible(&rhs_ty);
 
                 if lhs_ty.is_scalar() && rhs_ty.is_scalar() {
                     let mut tables = self.fcx.tables.borrow_mut();
@@ -192,7 +192,7 @@ fn fix_index_builtin_expr(&mut self, e: &hir::Expr) {
             // All valid indexing looks like this; might encounter non-valid indexes at this point
             if let ty::Ref(_, base_ty, _) = tables.expr_ty_adjusted(&base).sty {
                 let index_ty = tables.expr_ty_adjusted(&index);
-                let index_ty = self.fcx.resolve_type_vars_if_possible(&index_ty);
+                let index_ty = self.fcx.resolve_vars_if_possible(&index_ty);
 
                 if base_ty.builtin_index().is_some() && index_ty == self.fcx.tcx.types.usize {
                     // Remove the method call record