diff --git a/src/librustc_middle/arena.rs b/src/librustc_middle/arena.rs
index 2df878c3fb220..9b9207312e8dd 100644
--- a/src/librustc_middle/arena.rs
+++ b/src/librustc_middle/arena.rs
@@ -61,7 +61,7 @@ macro_rules! arena_types {
             [few] privacy_access_levels: rustc_middle::middle::privacy::AccessLevels,
             [few] foreign_module: rustc_middle::middle::cstore::ForeignModule,
             [few] foreign_modules: Vec<rustc_middle::middle::cstore::ForeignModule>,
-            [] upvars: rustc_data_structures::fx::FxIndexMap<rustc_hir::HirId, rustc_hir::Upvar>,
+            [] upvars_mentioned: rustc_data_structures::fx::FxIndexMap<rustc_hir::HirId, rustc_hir::Upvar>,
             [] object_safety_violations: rustc_middle::traits::ObjectSafetyViolation,
             [] codegen_unit: rustc_middle::mir::mono::CodegenUnit<$tcx>,
             [] attribute: rustc_ast::ast::Attribute,
diff --git a/src/librustc_middle/mir/mod.rs b/src/librustc_middle/mir/mod.rs
index 8247338ae0fad..c279213e5bd0e 100644
--- a/src/librustc_middle/mir/mod.rs
+++ b/src/librustc_middle/mir/mod.rs
@@ -2439,7 +2439,7 @@ impl<'tcx> Debug for Rvalue<'tcx> {
                             };
                             let mut struct_fmt = fmt.debug_struct(&name);
 
-                            if let Some(upvars) = tcx.upvars(def_id) {
+                            if let Some(upvars) = tcx.upvars_mentioned(def_id) {
                                 for (&var_id, place) in upvars.keys().zip(places) {
                                     let var_name = tcx.hir().name(var_id);
                                     struct_fmt.field(&var_name.as_str(), place);
@@ -2458,7 +2458,7 @@ impl<'tcx> Debug for Rvalue<'tcx> {
                             let name = format!("[generator@{:?}]", tcx.hir().span(hir_id));
                             let mut struct_fmt = fmt.debug_struct(&name);
 
-                            if let Some(upvars) = tcx.upvars(def_id) {
+                            if let Some(upvars) = tcx.upvars_mentioned(def_id) {
                                 for (&var_id, place) in upvars.keys().zip(places) {
                                     let var_name = tcx.hir().name(var_id);
                                     struct_fmt.field(&var_name.as_str(), place);
diff --git a/src/librustc_middle/query/mod.rs b/src/librustc_middle/query/mod.rs
index f7f5c5df8d67b..2445d484754d0 100644
--- a/src/librustc_middle/query/mod.rs
+++ b/src/librustc_middle/query/mod.rs
@@ -1040,7 +1040,7 @@ rustc_queries! {
             desc { "generating a postorder list of CrateNums" }
         }
 
-        query upvars(_: DefId) -> Option<&'tcx FxIndexMap<hir::HirId, hir::Upvar>> {
+        query upvars_mentioned(_: DefId) -> Option<&'tcx FxIndexMap<hir::HirId, hir::Upvar>> {
             eval_always
         }
         query maybe_unused_trait_import(def_id: LocalDefId) -> bool {
diff --git a/src/librustc_middle/ty/print/pretty.rs b/src/librustc_middle/ty/print/pretty.rs
index f03d91aa64b78..031ce6629bf4d 100644
--- a/src/librustc_middle/ty/print/pretty.rs
+++ b/src/librustc_middle/ty/print/pretty.rs
@@ -610,7 +610,7 @@ pub trait PrettyPrinter<'tcx>:
                         let mut sep = " ";
                         for (&var_id, upvar_ty) in self
                             .tcx()
-                            .upvars(did)
+                            .upvars_mentioned(did)
                             .as_ref()
                             .iter()
                             .flat_map(|v| v.keys())
@@ -659,7 +659,7 @@ pub trait PrettyPrinter<'tcx>:
                         let mut sep = " ";
                         for (&var_id, upvar_ty) in self
                             .tcx()
-                            .upvars(did)
+                            .upvars_mentioned(did)
                             .as_ref()
                             .iter()
                             .flat_map(|v| v.keys())
diff --git a/src/librustc_mir/borrow_check/diagnostics/mod.rs b/src/librustc_mir/borrow_check/diagnostics/mod.rs
index c218e3906fff2..ca8e54ea28649 100644
--- a/src/librustc_mir/borrow_check/diagnostics/mod.rs
+++ b/src/librustc_mir/borrow_check/diagnostics/mod.rs
@@ -377,11 +377,16 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     self.describe_field_from_ty(&ty, field, variant_index)
                 }
                 ty::Closure(def_id, _) | ty::Generator(def_id, _, _) => {
-                    // `tcx.upvars(def_id)` returns an `Option`, which is `None` in case
+                    // `tcx.upvars_mentioned(def_id)` returns an `Option`, which is `None` in case
                     // the closure comes from another crate. But in that case we wouldn't
                     // be borrowck'ing it, so we can just unwrap:
-                    let (&var_id, _) =
-                        self.infcx.tcx.upvars(def_id).unwrap().get_index(field.index()).unwrap();
+                    let (&var_id, _) = self
+                        .infcx
+                        .tcx
+                        .upvars_mentioned(def_id)
+                        .unwrap()
+                        .get_index(field.index())
+                        .unwrap();
 
                     self.infcx.tcx.hir().name(var_id).to_string()
                 }
@@ -809,7 +814,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let expr = &self.infcx.tcx.hir().expect_expr(hir_id).kind;
         debug!("closure_span: hir_id={:?} expr={:?}", hir_id, expr);
         if let hir::ExprKind::Closure(.., body_id, args_span, _) = expr {
-            for (upvar, place) in self.infcx.tcx.upvars(def_id)?.values().zip(places) {
+            for (upvar, place) in self.infcx.tcx.upvars_mentioned(def_id)?.values().zip(places) {
                 match place {
                     Operand::Copy(place) | Operand::Move(place)
                         if target_place == place.as_ref() =>
diff --git a/src/librustc_mir_build/hair/cx/expr.rs b/src/librustc_mir_build/hair/cx/expr.rs
index 99b59d16029ff..114bf5710402f 100644
--- a/src/librustc_mir_build/hair/cx/expr.rs
+++ b/src/librustc_mir_build/hair/cx/expr.rs
@@ -386,7 +386,7 @@ fn make_mirror_unadjusted<'a, 'tcx>(
             };
             let upvars = cx
                 .tcx
-                .upvars(def_id)
+                .upvars_mentioned(def_id)
                 .iter()
                 .flat_map(|upvars| upvars.iter())
                 .zip(substs.upvar_tys())
diff --git a/src/librustc_passes/liveness.rs b/src/librustc_passes/liveness.rs
index 2d7562ac1c34d..ece78d0251281 100644
--- a/src/librustc_passes/liveness.rs
+++ b/src/librustc_passes/liveness.rs
@@ -463,7 +463,7 @@ fn visit_expr<'tcx>(ir: &mut IrMaps<'tcx>, expr: &'tcx Expr<'tcx>) {
         hir::ExprKind::Path(hir::QPath::Resolved(_, ref path)) => {
             debug!("expr {}: path that leads to {:?}", expr.hir_id, path.res);
             if let Res::Local(var_hir_id) = path.res {
-                let upvars = ir.tcx.upvars(ir.body_owner);
+                let upvars = ir.tcx.upvars_mentioned(ir.body_owner);
                 if !upvars.map_or(false, |upvars| upvars.contains_key(&var_hir_id)) {
                     ir.add_live_node_for_node(expr.hir_id, ExprNode(expr.span));
                 }
@@ -481,8 +481,8 @@ fn visit_expr<'tcx>(ir: &mut IrMaps<'tcx>, expr: &'tcx Expr<'tcx>) {
             // construction site.
             let mut call_caps = Vec::new();
             let closure_def_id = ir.tcx.hir().local_def_id(expr.hir_id);
-            if let Some(upvars) = ir.tcx.upvars(closure_def_id) {
-                let parent_upvars = ir.tcx.upvars(ir.body_owner);
+            if let Some(upvars) = ir.tcx.upvars_mentioned(closure_def_id) {
+                let parent_upvars = ir.tcx.upvars_mentioned(ir.body_owner);
                 call_caps.extend(upvars.iter().filter_map(|(&var_id, upvar)| {
                     let has_parent =
                         parent_upvars.map_or(false, |upvars| upvars.contains_key(&var_id));
@@ -1364,7 +1364,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
     ) -> LiveNode {
         match path.res {
             Res::Local(hid) => {
-                let upvars = self.ir.tcx.upvars(self.ir.body_owner);
+                let upvars = self.ir.tcx.upvars_mentioned(self.ir.body_owner);
                 if !upvars.map_or(false, |upvars| upvars.contains_key(&hid)) {
                     self.access_var(hir_id, hid, succ, acc, path.span)
                 } else {
@@ -1529,7 +1529,7 @@ impl<'tcx> Liveness<'_, 'tcx> {
         match expr.kind {
             hir::ExprKind::Path(hir::QPath::Resolved(_, ref path)) => {
                 if let Res::Local(var_hid) = path.res {
-                    let upvars = self.ir.tcx.upvars(self.ir.body_owner);
+                    let upvars = self.ir.tcx.upvars_mentioned(self.ir.body_owner);
                     if !upvars.map_or(false, |upvars| upvars.contains_key(&var_hid)) {
                         // Assignment to an immutable variable or argument: only legal
                         // if there is no later assignment. If this local is actually
diff --git a/src/librustc_passes/upvars.rs b/src/librustc_passes/upvars.rs
index fb986caa415c9..99b4ef9d12fcd 100644
--- a/src/librustc_passes/upvars.rs
+++ b/src/librustc_passes/upvars.rs
@@ -10,7 +10,7 @@ use rustc_middle::ty::TyCtxt;
 use rustc_span::Span;
 
 pub fn provide(providers: &mut Providers<'_>) {
-    providers.upvars = |tcx, def_id| {
+    providers.upvars_mentioned = |tcx, def_id| {
         if !tcx.is_closure(def_id) {
             return None;
         }
@@ -89,7 +89,7 @@ impl Visitor<'tcx> for CaptureCollector<'a, 'tcx> {
     fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
         if let hir::ExprKind::Closure(..) = expr.kind {
             let closure_def_id = self.tcx.hir().local_def_id(expr.hir_id);
-            if let Some(upvars) = self.tcx.upvars(closure_def_id) {
+            if let Some(upvars) = self.tcx.upvars_mentioned(closure_def_id) {
                 // Every capture of a closure expression is a local in scope,
                 // that is moved/copied/borrowed into the closure value, and
                 // for this analysis they are like any other access to a local.
diff --git a/src/librustc_trait_selection/traits/error_reporting/suggestions.rs b/src/librustc_trait_selection/traits/error_reporting/suggestions.rs
index 5c85855535e38..31992f298080e 100644
--- a/src/librustc_trait_selection/traits/error_reporting/suggestions.rs
+++ b/src/librustc_trait_selection/traits/error_reporting/suggestions.rs
@@ -1380,7 +1380,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
         let mut interior_or_upvar_span = None;
         let mut interior_extra_info = None;
 
-        if let Some(upvars) = self.tcx.upvars(generator_did) {
+        if let Some(upvars) = self.tcx.upvars_mentioned(generator_did) {
             interior_or_upvar_span = upvars.iter().find_map(|(upvar_id, upvar)| {
                 let upvar_ty = tables.node_type(*upvar_id);
                 let upvar_ty = self.resolve_vars_if_possible(&upvar_ty);
diff --git a/src/librustc_typeck/check/closure.rs b/src/librustc_typeck/check/closure.rs
index 8fa901d8a984a..af93f9bc8c0a7 100644
--- a/src/librustc_typeck/check/closure.rs
+++ b/src/librustc_typeck/check/closure.rs
@@ -90,18 +90,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             base_substs.extend_to(self.tcx, expr_def_id.to_def_id(), |param, _| match param.kind {
                 GenericParamDefKind::Lifetime => span_bug!(expr.span, "closure has lifetime param"),
                 GenericParamDefKind::Type { .. } => if param.index as usize == tupled_upvars_idx {
-                    self.tcx.mk_tup(self.tcx.upvars(expr_def_id).iter().flat_map(|upvars| {
-                        upvars.iter().map(|(&var_hir_id, _)| {
-                            // Create type variables (for now) to represent the transformed
-                            // types of upvars. These will be unified during the upvar
-                            // inference phase (`upvar.rs`).
-                            self.infcx.next_ty_var(TypeVariableOrigin {
-                                // FIXME(eddyb) distinguish upvar inference variables from the rest.
-                                kind: TypeVariableOriginKind::ClosureSynthetic,
-                                span: self.tcx.hir().span(var_hir_id),
+                    self.tcx.mk_tup(self.tcx.upvars_mentioned(expr_def_id).iter().flat_map(
+                        |upvars| {
+                            upvars.iter().map(|(&var_hir_id, _)| {
+                                // Create type variables (for now) to represent the transformed
+                                // types of upvars. These will be unified during the upvar
+                                // inference phase (`upvar.rs`).
+                                self.infcx.next_ty_var(TypeVariableOrigin {
+                                    // FIXME(eddyb) distinguish upvar inference variables from the rest.
+                                    kind: TypeVariableOriginKind::ClosureSynthetic,
+                                    span: self.tcx.hir().span(var_hir_id),
+                                })
                             })
-                        })
-                    }))
+                        },
+                    ))
                 } else {
                     // Create type variables (for now) to represent the various
                     // pieces of information kept in `{Closure,Generic}Substs`.
diff --git a/src/librustc_typeck/check/upvar.rs b/src/librustc_typeck/check/upvar.rs
index 6aa8242193d5f..8707e4fe84a22 100644
--- a/src/librustc_typeck/check/upvar.rs
+++ b/src/librustc_typeck/check/upvar.rs
@@ -111,7 +111,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             None
         };
 
-        if let Some(upvars) = self.tcx.upvars(closure_def_id) {
+        if let Some(upvars) = self.tcx.upvars_mentioned(closure_def_id) {
             let mut upvar_list: FxIndexMap<hir::HirId, ty::UpvarId> =
                 FxIndexMap::with_capacity_and_hasher(upvars.len(), Default::default());
             for (&var_hir_id, _) in upvars.iter() {
@@ -218,7 +218,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let tcx = self.tcx;
         let closure_def_id = tcx.hir().local_def_id(closure_id);
 
-        tcx.upvars(closure_def_id)
+        tcx.upvars_mentioned(closure_def_id)
             .iter()
             .flat_map(|upvars| {
                 upvars.iter().map(|(&var_hir_id, _)| {
diff --git a/src/librustc_typeck/expr_use_visitor.rs b/src/librustc_typeck/expr_use_visitor.rs
index 9ba00faec4978..53973eba22940 100644
--- a/src/librustc_typeck/expr_use_visitor.rs
+++ b/src/librustc_typeck/expr_use_visitor.rs
@@ -539,7 +539,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
         debug!("walk_captures({:?})", closure_expr);
 
         let closure_def_id = self.tcx().hir().local_def_id(closure_expr.hir_id);
-        if let Some(upvars) = self.tcx().upvars(closure_def_id) {
+        if let Some(upvars) = self.tcx().upvars_mentioned(closure_def_id) {
             for &var_id in upvars.keys() {
                 let upvar_id = ty::UpvarId {
                     var_path: ty::UpvarPath { hir_id: var_id },
diff --git a/src/librustc_typeck/mem_categorization.rs b/src/librustc_typeck/mem_categorization.rs
index 71f3e2d03c9ff..93d01ccd66f1e 100644
--- a/src/librustc_typeck/mem_categorization.rs
+++ b/src/librustc_typeck/mem_categorization.rs
@@ -159,7 +159,7 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> {
             infcx,
             param_env,
             body_owner,
-            upvars: infcx.tcx.upvars(body_owner),
+            upvars: infcx.tcx.upvars_mentioned(body_owner),
         }
     }