add def_id and substs to ConstraintCategory::CallArgument

10 files changed, 77 insertions, 45 deletions

diff --git a/compiler/rustc_borrowck/src/constraints/mod.rs b/compiler/rustc_borrowck/src/constraints/mod.rs
index 6d5466c0c41..a504d0c9122 100644
--- a/compiler/rustc_borrowck/src/constraints/mod.rs
+++ b/compiler/rustc_borrowck/src/constraints/mod.rs
@@ -95,7 +95,7 @@ pub struct OutlivesConstraint<'tcx> {
     pub span: Span,
 
     /// What caused this constraint?
-    pub category: ConstraintCategory,
+    pub category: ConstraintCategory<'tcx>,
 
     /// Variance diagnostic information
     pub variance_info: VarianceDiagInfo<'tcx>,
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index da5f56704d4..191574d7a8f 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -788,7 +788,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         err: &mut Diagnostic,
         location: Location,
         issued_borrow: &BorrowData<'tcx>,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) {
         let used_in_call = matches!(
             explanation,
@@ -1088,7 +1088,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 BorrowExplanation::MustBeValidFor {
                     category:
                         category @ (ConstraintCategory::Return(_)
-                        | ConstraintCategory::CallArgument
+                        | ConstraintCategory::CallArgument(_)
                         | ConstraintCategory::OpaqueType),
                     from_closure: false,
                     ref region_name,
@@ -1147,7 +1147,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         borrow: &BorrowData<'tcx>,
         drop_span: Span,
         borrow_spans: UseSpans<'tcx>,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
         debug!(
             "report_local_value_does_not_live_long_enough(\
@@ -1352,7 +1352,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         drop_span: Span,
         borrow_spans: UseSpans<'tcx>,
         proper_span: Span,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
         debug!(
             "report_temporary_value_does_not_live_long_enough(\
@@ -1410,7 +1410,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         borrow: &BorrowData<'tcx>,
         borrow_span: Span,
         return_span: Span,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         opt_place_desc: Option<&String>,
     ) -> Option<DiagnosticBuilder<'cx, ErrorGuaranteed>> {
         let return_kind = match category {
@@ -1508,7 +1508,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         use_span: UseSpans<'tcx>,
         var_span: Span,
         fr_name: &RegionName,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         constraint_span: Span,
         captured_var: &str,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
@@ -1559,7 +1559,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 let msg = format!("{} is returned here", kind);
                 err.span_note(constraint_span, &msg);
             }
-            ConstraintCategory::CallArgument => {
+            ConstraintCategory::CallArgument(_) => {
                 fr_name.highlight_region_name(&mut err);
                 if matches!(use_span.generator_kind(), Some(GeneratorKind::Async(_))) {
                     err.note(
diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index 0b6be453b92..5d9e5907dff 100644
--- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -24,7 +24,7 @@ use crate::{
 use super::{find_use, RegionName, UseSpans};
 
 #[derive(Debug)]
-pub(crate) enum BorrowExplanation {
+pub(crate) enum BorrowExplanation<'tcx> {
     UsedLater(LaterUseKind, Span, Option<Span>),
     UsedLaterInLoop(LaterUseKind, Span, Option<Span>),
     UsedLaterWhenDropped {
@@ -33,7 +33,7 @@ pub(crate) enum BorrowExplanation {
         should_note_order: bool,
     },
     MustBeValidFor {
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         from_closure: bool,
         span: Span,
         region_name: RegionName,
@@ -51,11 +51,11 @@ pub(crate) enum LaterUseKind {
     Other,
 }
 
-impl BorrowExplanation {
+impl<'tcx> BorrowExplanation<'tcx> {
     pub(crate) fn is_explained(&self) -> bool {
         !matches!(self, BorrowExplanation::Unexplained)
     }
-    pub(crate) fn add_explanation_to_diagnostic<'tcx>(
+    pub(crate) fn add_explanation_to_diagnostic(
         &self,
         tcx: TyCtxt<'tcx>,
         body: &Body<'tcx>,
@@ -276,7 +276,7 @@ impl BorrowExplanation {
     pub(crate) fn add_lifetime_bound_suggestion_to_diagnostic(
         &self,
         err: &mut Diagnostic,
-        category: &ConstraintCategory,
+        category: &ConstraintCategory<'tcx>,
         span: Span,
         region_name: &RegionName,
     ) {
@@ -305,7 +305,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         &self,
         borrow_region: RegionVid,
         outlived_region: RegionVid,
-    ) -> (ConstraintCategory, bool, Span, Option<RegionName>) {
+    ) -> (ConstraintCategory<'tcx>, bool, Span, Option<RegionName>) {
         let BlameConstraint { category, from_closure, cause, variance_info: _ } =
             self.regioncx.best_blame_constraint(
                 &self.body,
@@ -337,7 +337,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         location: Location,
         borrow: &BorrowData<'tcx>,
         kind_place: Option<(WriteKind, Place<'tcx>)>,
-    ) -> BorrowExplanation {
+    ) -> BorrowExplanation<'tcx> {
         debug!(
             "explain_why_borrow_contains_point(location={:?}, borrow={:?}, kind_place={:?})",
             location, borrow, kind_place
diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs
index dc6337c54ed..2c460bcb72d 100644
--- a/compiler/rustc_borrowck/src/region_infer/mod.rs
+++ b/compiler/rustc_borrowck/src/region_infer/mod.rs
@@ -87,7 +87,7 @@ pub struct RegionInferenceContext<'tcx> {
 
     /// Map closure bounds to a `Span` that should be used for error reporting.
     closure_bounds_mapping:
-        FxHashMap<Location, FxHashMap<(RegionVid, RegionVid), (ConstraintCategory, Span)>>,
+        FxHashMap<Location, FxHashMap<(RegionVid, RegionVid), (ConstraintCategory<'tcx>, Span)>>,
 
     /// Map universe indexes to information on why we created it.
     universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
@@ -259,7 +259,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         member_constraints_in: MemberConstraintSet<'tcx, RegionVid>,
         closure_bounds_mapping: FxHashMap<
             Location,
-            FxHashMap<(RegionVid, RegionVid), (ConstraintCategory, Span)>,
+            FxHashMap<(RegionVid, RegionVid), (ConstraintCategory<'tcx>, Span)>,
         >,
         universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
         type_tests: Vec<TypeTest<'tcx>>,
@@ -1772,7 +1772,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         fr1: RegionVid,
         fr1_origin: NllRegionVariableOrigin,
         fr2: RegionVid,
-    ) -> (ConstraintCategory, ObligationCause<'tcx>) {
+    ) -> (ConstraintCategory<'tcx>, ObligationCause<'tcx>) {
         let BlameConstraint { category, cause, .. } =
             self.best_blame_constraint(body, fr1, fr1_origin, |r| {
                 self.provides_universal_region(r, fr1, fr2)
@@ -2270,7 +2270,7 @@ impl<'tcx> ClosureRegionRequirementsExt<'tcx> for ClosureRegionRequirements<'tcx
 
 #[derive(Clone, Debug)]
 pub struct BlameConstraint<'tcx> {
-    pub category: ConstraintCategory,
+    pub category: ConstraintCategory<'tcx>,
     pub from_closure: bool,
     pub cause: ObligationCause<'tcx>,
     pub variance_info: ty::VarianceDiagInfo<'tcx>,
diff --git a/compiler/rustc_borrowck/src/type_check/canonical.rs b/compiler/rustc_borrowck/src/type_check/canonical.rs
index 3856b7f4a4b..55c0bf05b48 100644
--- a/compiler/rustc_borrowck/src/type_check/canonical.rs
+++ b/compiler/rustc_borrowck/src/type_check/canonical.rs
@@ -28,7 +28,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
     pub(super) fn fully_perform_op<R, Op>(
         &mut self,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         op: Op,
     ) -> Fallible<R>
     where
@@ -83,11 +83,12 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         instantiated
     }
 
+    #[instrument(skip(self), level = "debug")]
     pub(super) fn prove_trait_ref(
         &mut self,
         trait_ref: ty::TraitRef<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         self.prove_predicates(
             Some(ty::Binder::dummy(ty::PredicateKind::Trait(ty::TraitPredicate {
@@ -113,6 +114,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             .into_iter()
             .zip(instantiated_predicates.spans.into_iter())
         {
+            debug!(?predicate);
             let predicate = self.normalize(predicate, locations);
             self.prove_predicate(predicate, locations, ConstraintCategory::Predicate(span));
         }
@@ -122,7 +124,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         &mut self,
         predicates: impl IntoIterator<Item = impl ToPredicate<'tcx>>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         for predicate in predicates {
             let predicate = predicate.to_predicate(self.tcx());
@@ -137,7 +139,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         &mut self,
         predicate: ty::Predicate<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         let param_env = self.param_env;
         self.fully_perform_op(
diff --git a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
index f11a94d7ddd..3c9e3870aea 100644
--- a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
+++ b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
@@ -27,7 +27,7 @@ pub(crate) struct ConstraintConversion<'a, 'tcx> {
     param_env: ty::ParamEnv<'tcx>,
     locations: Locations,
     span: Span,
-    category: ConstraintCategory,
+    category: ConstraintCategory<'tcx>,
     constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
 }
 
@@ -40,7 +40,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
         param_env: ty::ParamEnv<'tcx>,
         locations: Locations,
         span: Span,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
     ) -> Self {
         Self {
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index 34bc87b20c7..bf52b1be678 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -162,6 +162,8 @@ pub(crate) fn type_check<'mir, 'tcx>(
         &mut constraints,
     );
 
+    debug!(?normalized_inputs_and_output);
+
     for u in ty::UniverseIndex::ROOT..infcx.universe() {
         let info = UniverseInfo::other();
         constraints.universe_causes.insert(u, info);
@@ -185,6 +187,7 @@ pub(crate) fn type_check<'mir, 'tcx>(
         implicit_region_bound,
         &mut borrowck_context,
         |mut cx| {
+            debug!("inside extra closure of type_check_internal");
             cx.equate_inputs_and_outputs(&body, universal_regions, &normalized_inputs_and_output);
             liveness::generate(
                 &mut cx,
@@ -257,6 +260,7 @@ fn type_check_internal<'a, 'tcx, R>(
     borrowck_context: &'a mut BorrowCheckContext<'a, 'tcx>,
     extra: impl FnOnce(TypeChecker<'a, 'tcx>) -> R,
 ) -> R {
+    debug!("body: {:#?}", body);
     let mut checker = TypeChecker::new(
         infcx,
         body,
@@ -934,8 +938,8 @@ pub(crate) struct MirTypeckRegionConstraints<'tcx> {
 
     pub(crate) member_constraints: MemberConstraintSet<'tcx, RegionVid>,
 
-    pub(crate) closure_bounds_mapping:
-        FxHashMap<Location, FxHashMap<(RegionVid, RegionVid), (ConstraintCategory, Span)>>,
+    crate closure_bounds_mapping:
+        FxHashMap<Location, FxHashMap<(RegionVid, RegionVid), (ConstraintCategory<'tcx>, Span)>>,
 
     pub(crate) universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
 
@@ -1125,7 +1129,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
     fn push_region_constraints(
         &mut self,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         data: &QueryRegionConstraints<'tcx>,
     ) {
         debug!("constraints generated: {:#?}", data);
@@ -1150,7 +1154,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         sub: Ty<'tcx>,
         sup: Ty<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         // Use this order of parameters because the sup type is usually the
         // "expected" type in diagnostics.
@@ -1163,7 +1167,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         expected: Ty<'tcx>,
         found: Ty<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         self.relate_types(expected, ty::Variance::Invariant, found, locations, category)
     }
@@ -1175,7 +1179,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         v: ty::Variance,
         user_ty: &UserTypeProjection,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         let annotated_type = self.user_type_annotations[user_ty.base].inferred_ty;
         let mut curr_projected_ty = PlaceTy::from_ty(annotated_type);
@@ -1212,6 +1216,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
     #[instrument(skip(self, body, location), level = "debug")]
     fn check_stmt(&mut self, body: &Body<'tcx>, stmt: &Statement<'tcx>, location: Location) {
         let tcx = self.tcx();
+        debug!("stmt kind: {:?}", stmt.kind);
         match stmt.kind {
             StatementKind::Assign(box (ref place, ref rv)) => {
                 // Assignments to temporaries are not "interesting";
@@ -1251,9 +1256,13 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 );
 
                 let place_ty = place.ty(body, tcx).ty;
+                debug!(?place_ty);
                 let place_ty = self.normalize(place_ty, location);
+                debug!("place_ty normalized: {:?}", place_ty);
                 let rv_ty = rv.ty(body, tcx);
+                debug!(?rv_ty);
                 let rv_ty = self.normalize(rv_ty, location);
+                debug!("normalized rv_ty: {:?}", rv_ty);
                 if let Err(terr) =
                     self.sub_types(rv_ty, place_ty, location.to_locations(), category)
                 {
@@ -1347,6 +1356,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         term_location: Location,
     ) {
         let tcx = self.tcx();
+        debug!("terminator kind: {:?}", term.kind);
         match term.kind {
             TerminatorKind::Goto { .. }
             | TerminatorKind::Resume
@@ -1404,7 +1414,12 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 // FIXME: check the values
             }
             TerminatorKind::Call {
-                ref func, ref args, destination, target, from_hir_call, ..
+                ref func,
+                ref args,
+                ref destination,
+                from_hir_call,
+                fn_span,
+                ..
             } => {
                 self.check_operand(func, term_location);
                 for arg in args {
@@ -1413,6 +1428,8 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
 
                 let func_ty = func.ty(body, tcx);
                 debug!("check_terminator: call, func_ty={:?}", func_ty);
+                debug!("func_ty.kind: {:?}", func_ty.kind());
+                debug!(?fn_span);
                 let sig = match func_ty.kind() {
                     ty::FnDef(..) | ty::FnPtr(_) => func_ty.fn_sig(tcx),
                     _ => {
@@ -1425,6 +1442,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     LateBoundRegionConversionTime::FnCall,
                     sig,
                 );
+                debug!(?sig);
                 let sig = self.normalize(sig, term_location);
                 self.check_call_dest(body, term, &sig, destination, target, term_location);
 
@@ -1585,11 +1603,25 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         if args.len() < sig.inputs().len() || (args.len() > sig.inputs().len() && !sig.c_variadic) {
             span_mirbug!(self, term, "call to {:?} with wrong # of args", sig);
         }
+
+        let call_arg = if let TerminatorKind::Call { func, .. } = &term.kind {
+            let func_ty = func.ty(body, self.infcx.tcx);
+            if let ty::FnDef(fn_did, substs) = func_ty.kind() {
+                Some((*fn_did, *substs))
+            } else {
+                None
+            }
+        } else {
+            None
+        };
+        debug!(?call_arg);
+
         for (n, (fn_arg, op_arg)) in iter::zip(sig.inputs(), args).enumerate() {
             let op_arg_ty = op_arg.ty(body, self.tcx());
+
             let op_arg_ty = self.normalize(op_arg_ty, term_location);
             let category = if from_hir_call {
-                ConstraintCategory::CallArgument
+                ConstraintCategory::CallArgument(call_arg)
             } else {
                 ConstraintCategory::Boring
             };
@@ -1841,6 +1873,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         }
     }
 
+    #[instrument(skip(self, body), level = "debug")]
     fn check_rvalue(&mut self, body: &Body<'tcx>, rvalue: &Rvalue<'tcx>, location: Location) {
         let tcx = self.tcx();
 
diff --git a/compiler/rustc_borrowck/src/type_check/relate_tys.rs b/compiler/rustc_borrowck/src/type_check/relate_tys.rs
index f98d2c3128c..c45850c6d84 100644
--- a/compiler/rustc_borrowck/src/type_check/relate_tys.rs
+++ b/compiler/rustc_borrowck/src/type_check/relate_tys.rs
@@ -28,7 +28,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         v: ty::Variance,
         b: Ty<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         TypeRelating::new(
             self.infcx,
@@ -47,7 +47,7 @@ struct NllTypeRelatingDelegate<'me, 'bccx, 'tcx> {
     locations: Locations,
 
     /// What category do we assign the resulting `'a: 'b` relationships?
-    category: ConstraintCategory,
+    category: ConstraintCategory<'tcx>,
 
     /// Information so that error reporting knows what types we are relating
     /// when reporting a bound region error.
@@ -58,7 +58,7 @@ impl<'me, 'bccx, 'tcx> NllTypeRelatingDelegate<'me, 'bccx, 'tcx> {
     fn new(
         type_checker: &'me mut TypeChecker<'bccx, 'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         universe_info: UniverseInfo<'tcx>,
     ) -> Self {
         Self { type_checker, locations, category, universe_info }
diff --git a/compiler/rustc_middle/src/mir/query.rs b/compiler/rustc_middle/src/mir/query.rs
index 7f7b8bdfc14..4f71e3a8234 100644
--- a/compiler/rustc_middle/src/mir/query.rs
+++ b/compiler/rustc_middle/src/mir/query.rs
@@ -1,7 +1,7 @@
 //! Values computed by queries that use MIR.
 
 use crate::mir::{self, Body, Promoted};
-use crate::ty::{self, OpaqueHiddenType, Ty, TyCtxt};
+use crate::ty::{self, subst::SubstsRef, OpaqueHiddenType, Ty, TyCtxt};
 use rustc_data_structures::stable_map::FxHashMap;
 use rustc_data_structures::vec_map::VecMap;
 use rustc_errors::ErrorGuaranteed;
@@ -338,12 +338,9 @@ pub struct ClosureOutlivesRequirement<'tcx> {
     pub blame_span: Span,
 
     // ... due to this reason.
-    pub category: ConstraintCategory,
+    pub category: ConstraintCategory<'tcx>,
 }
 
-// Make sure this enum doesn't unintentionally grow
-rustc_data_structures::static_assert_size!(ConstraintCategory, 12);
-
 /// Outlives-constraints can be categorized to determine whether and why they
 /// are interesting (for error reporting). Order of variants indicates sort
 /// order of the category, thereby influencing diagnostic output.
@@ -351,7 +348,7 @@ rustc_data_structures::static_assert_size!(ConstraintCategory, 12);
 /// See also `rustc_const_eval::borrow_check::constraints`.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Hash)]
 #[derive(TyEncodable, TyDecodable, HashStable)]
-pub enum ConstraintCategory {
+pub enum ConstraintCategory<'tcx> {
     Return(ReturnConstraint),
     Yield,
     UseAsConst,
@@ -363,7 +360,7 @@ pub enum ConstraintCategory {
     ///
     /// We try to get the category that the closure used when reporting this.
     ClosureBounds,
-    CallArgument,
+    CallArgument(Option<(DefId, SubstsRef<'tcx>)>),
     CopyBound,
     SizedBound,
     Assignment,
diff --git a/compiler/rustc_middle/src/ty/impls_ty.rs b/compiler/rustc_middle/src/ty/impls_ty.rs
index 65c9b1aed05..d6b5e9ddfbd 100644
--- a/compiler/rustc_middle/src/ty/impls_ty.rs
+++ b/compiler/rustc_middle/src/ty/impls_ty.rs
@@ -135,8 +135,8 @@ impl<'a> HashStable<StableHashingContext<'a>> for ty::RegionKind {
             ty::RePlaceholder(p) => {
                 p.hash_stable(hcx, hasher);
             }
-            ty::ReVar(..) => {
-                bug!("StableHasher: unexpected region {:?}", *self)
+            ty::ReVar(reg_vid) => {
+                reg_vid.hash_stable(hcx, hasher);
             }
         }
     }