Stop creating anonymous late lifetimes.

5 files changed, 4 insertions, 85 deletions

diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/find_anon_type.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/find_anon_type.rs
index e5ae835e813..c1b201da691 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/find_anon_type.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/find_anon_type.rs
@@ -100,23 +100,6 @@ impl<'tcx> Visitor<'tcx> for FindNestedTypeVisitor<'tcx> {
                 // the lifetime of the TyRptr
                 let hir_id = lifetime.hir_id;
                 match (self.tcx.named_region(hir_id), self.bound_region) {
-                    // Find the index of the anonymous region that was part of the
-                    // error. We will then search the function parameters for a bound
-                    // region at the right depth with the same index
-                    (
-                        Some(rl::Region::LateBoundAnon(debruijn_index, _, anon_index)),
-                        ty::BrAnon(br_index),
-                    ) => {
-                        debug!(
-                            "LateBoundAnon depth = {:?} anon_index = {:?} br_index={:?}",
-                            debruijn_index, anon_index, br_index
-                        );
-                        if debruijn_index == self.current_index && anon_index == br_index {
-                            self.found_type = Some(arg);
-                            return; // we can stop visiting now
-                        }
-                    }
-
                     // Find the index of the named region that was part of the
                     // error. We will then search the function parameters for a bound
                     // region at the right depth with the same index
@@ -151,8 +134,7 @@ impl<'tcx> Visitor<'tcx> for FindNestedTypeVisitor<'tcx> {
                             rl::Region::Static
                             | rl::Region::Free(_, _)
                             | rl::Region::EarlyBound(_, _)
-                            | rl::Region::LateBound(_, _, _)
-                            | rl::Region::LateBoundAnon(_, _, _),
+                            | rl::Region::LateBound(_, _, _),
                         )
                         | None,
                         _,
@@ -206,16 +188,6 @@ impl<'tcx> Visitor<'tcx> for TyPathVisitor<'tcx> {
     fn visit_lifetime(&mut self, lifetime: &hir::Lifetime) {
         match (self.tcx.named_region(lifetime.hir_id), self.bound_region) {
             // the lifetime of the TyPath!
-            (
-                Some(rl::Region::LateBoundAnon(debruijn_index, _, anon_index)),
-                ty::BrAnon(br_index),
-            ) => {
-                if debruijn_index == self.current_index && anon_index == br_index {
-                    self.found_it = true;
-                    return;
-                }
-            }
-
             (Some(rl::Region::EarlyBound(_, id)), ty::BrNamed(def_id, _)) => {
                 debug!("EarlyBound id={:?} def_id={:?}", id, def_id);
                 if id == def_id {
@@ -239,7 +211,6 @@ impl<'tcx> Visitor<'tcx> for TyPathVisitor<'tcx> {
                     rl::Region::Static
                     | rl::Region::EarlyBound(_, _)
                     | rl::Region::LateBound(_, _, _)
-                    | rl::Region::LateBoundAnon(_, _, _)
                     | rl::Region::Free(_, _),
                 )
                 | None,
diff --git a/compiler/rustc_middle/src/middle/resolve_lifetime.rs b/compiler/rustc_middle/src/middle/resolve_lifetime.rs
index c71ba7b1753..9b2f4456705 100644
--- a/compiler/rustc_middle/src/middle/resolve_lifetime.rs
+++ b/compiler/rustc_middle/src/middle/resolve_lifetime.rs
@@ -12,7 +12,6 @@ pub enum Region {
     Static,
     EarlyBound(/* index */ u32, /* lifetime decl */ DefId),
     LateBound(ty::DebruijnIndex, /* late-bound index */ u32, /* lifetime decl */ DefId),
-    LateBoundAnon(ty::DebruijnIndex, /* late-bound index */ u32, /* anon index */ u32),
     Free(DefId, /* lifetime decl */ DefId),
 }
 
diff --git a/compiler/rustc_resolve/src/late/lifetimes.rs b/compiler/rustc_resolve/src/late/lifetimes.rs
index 7b751c663d2..1d83d57fe38 100644
--- a/compiler/rustc_resolve/src/late/lifetimes.rs
+++ b/compiler/rustc_resolve/src/late/lifetimes.rs
@@ -24,7 +24,6 @@ use rustc_span::def_id::DefId;
 use rustc_span::symbol::{sym, Ident};
 use rustc_span::Span;
 use std::borrow::Cow;
-use std::cell::Cell;
 use std::fmt;
 use std::mem::take;
 
@@ -33,8 +32,6 @@ trait RegionExt {
 
     fn late(index: u32, hir_map: Map<'_>, param: &GenericParam<'_>) -> (LocalDefId, Region);
 
-    fn late_anon(named_late_bound_vars: u32, index: &Cell<u32>) -> Region;
-
     fn id(&self) -> Option<DefId>;
 
     fn shifted(self, amount: u32) -> Region;
@@ -65,16 +62,9 @@ impl RegionExt for Region {
         (def_id, Region::LateBound(depth, idx, def_id.to_def_id()))
     }
 
-    fn late_anon(named_late_bound_vars: u32, index: &Cell<u32>) -> Region {
-        let i = index.get();
-        index.set(i + 1);
-        let depth = ty::INNERMOST;
-        Region::LateBoundAnon(depth, named_late_bound_vars + i, i)
-    }
-
     fn id(&self) -> Option<DefId> {
         match *self {
-            Region::Static | Region::LateBoundAnon(..) => None,
+            Region::Static => None,
 
             Region::EarlyBound(_, id) | Region::LateBound(_, _, id) | Region::Free(_, id) => {
                 Some(id)
@@ -87,9 +77,6 @@ impl RegionExt for Region {
             Region::LateBound(debruijn, idx, id) => {
                 Region::LateBound(debruijn.shifted_in(amount), idx, id)
             }
-            Region::LateBoundAnon(debruijn, index, anon_index) => {
-                Region::LateBoundAnon(debruijn.shifted_in(amount), index, anon_index)
-            }
             _ => self,
         }
     }
@@ -99,9 +86,6 @@ impl RegionExt for Region {
             Region::LateBound(debruijn, index, id) => {
                 Region::LateBound(debruijn.shifted_out_to_binder(binder), index, id)
             }
-            Region::LateBoundAnon(debruijn, index, anon_index) => {
-                Region::LateBoundAnon(debruijn.shifted_out_to_binder(binder), index, anon_index)
-            }
             _ => self,
         }
     }
@@ -193,10 +177,6 @@ enum Scope<'a> {
 
         s: ScopeRef<'a>,
 
-        /// In some cases not allowing late bounds allows us to avoid ICEs.
-        /// This is almost ways set to true.
-        allow_late_bound: bool,
-
         /// If this binder comes from a where clause, specify how it was created.
         /// This is used to diagnose inaccessible lifetimes in APIT:
         /// ```ignore (illustrative)
@@ -272,7 +252,6 @@ impl<'a> fmt::Debug for TruncatedScopeDebug<'a> {
                 opaque_type_parent,
                 scope_type,
                 hir_id,
-                allow_late_bound,
                 where_bound_origin,
                 s: _,
             } => f
@@ -282,7 +261,6 @@ impl<'a> fmt::Debug for TruncatedScopeDebug<'a> {
                 .field("opaque_type_parent", opaque_type_parent)
                 .field("scope_type", scope_type)
                 .field("hir_id", hir_id)
-                .field("allow_late_bound", allow_late_bound)
                 .field("where_bound_origin", where_bound_origin)
                 .field("s", &"..")
                 .finish(),
@@ -468,9 +446,6 @@ fn late_region_as_bound_region<'tcx>(tcx: TyCtxt<'tcx>, region: &Region) -> ty::
             let name = tcx.hir().name(tcx.hir().local_def_id_to_hir_id(def_id.expect_local()));
             ty::BoundVariableKind::Region(ty::BrNamed(*def_id, name))
         }
-        Region::LateBoundAnon(_, _, anon_idx) => {
-            ty::BoundVariableKind::Region(ty::BrAnon(*anon_idx))
-        }
         _ => bug!("{:?} is not a late region", region),
     }
 }
@@ -605,7 +580,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                 next_early_index,
                 opaque_type_parent: false,
                 scope_type: BinderScopeType::Normal,
-                allow_late_bound: true,
                 where_bound_origin: None,
             };
 
@@ -724,7 +698,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     opaque_type_parent: true,
                     scope_type: BinderScopeType::Normal,
                     s: ROOT_SCOPE,
-                    allow_late_bound: false,
                     where_bound_origin: None,
                 };
                 self.with(scope, |this| {
@@ -777,7 +750,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     next_early_index,
                     opaque_type_parent: false,
                     scope_type: BinderScopeType::Normal,
-                    allow_late_bound: true,
                     where_bound_origin: None,
                 };
                 self.with(scope, |this| {
@@ -942,7 +914,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     s: self.scope,
                     opaque_type_parent: false,
                     scope_type: BinderScopeType::Normal,
-                    allow_late_bound: false,
                     where_bound_origin: None,
                 };
                 self.with(scope, |this| {
@@ -997,7 +968,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     s: self.scope,
                     opaque_type_parent: true,
                     scope_type: BinderScopeType::Normal,
-                    allow_late_bound: false,
                     where_bound_origin: None,
                 };
                 self.with(scope, |this| {
@@ -1059,7 +1029,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     s: self.scope,
                     opaque_type_parent: true,
                     scope_type: BinderScopeType::Normal,
-                    allow_late_bound: true,
                     where_bound_origin: None,
                 };
                 self.with(scope, |this| {
@@ -1173,7 +1142,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                             next_early_index,
                             opaque_type_parent: false,
                             scope_type: BinderScopeType::Normal,
-                            allow_late_bound: true,
                             where_bound_origin: Some(origin),
                         };
                         this.with(scope, |this| {
@@ -1246,7 +1214,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     next_early_index: self.next_early_index(),
                     opaque_type_parent: false,
                     scope_type,
-                    allow_late_bound: true,
                     where_bound_origin: None,
                 };
                 self.with(scope, |this| {
@@ -1297,7 +1264,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
             next_early_index,
             opaque_type_parent: false,
             scope_type,
-            allow_late_bound: true,
             where_bound_origin: None,
         };
         self.with(scope, |this| {
@@ -1551,7 +1517,6 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
             s: self.scope,
             opaque_type_parent: true,
             scope_type: BinderScopeType::Normal,
-            allow_late_bound: true,
             where_bound_origin: None,
         };
         self.with(scope, walk);
diff --git a/compiler/rustc_typeck/src/astconv/mod.rs b/compiler/rustc_typeck/src/astconv/mod.rs
index 58f4f02052f..08e8e6f7d0f 100644
--- a/compiler/rustc_typeck/src/astconv/mod.rs
+++ b/compiler/rustc_typeck/src/astconv/mod.rs
@@ -221,14 +221,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 tcx.mk_region(ty::ReLateBound(debruijn, br))
             }
 
-            Some(rl::Region::LateBoundAnon(debruijn, index, anon_index)) => {
-                let br = ty::BoundRegion {
-                    var: ty::BoundVar::from_u32(index),
-                    kind: ty::BrAnon(anon_index),
-                };
-                tcx.mk_region(ty::ReLateBound(debruijn, br))
-            }
-
             Some(rl::Region::EarlyBound(index, id)) => {
                 let name = lifetime_name(id.expect_local());
                 tcx.mk_region(ty::ReEarlyBound(ty::EarlyBoundRegion { def_id: id, index, name }))
diff --git a/compiler/rustc_typeck/src/collect.rs b/compiler/rustc_typeck/src/collect.rs
index 0fcbfa734f8..d725c9d28ac 100644
--- a/compiler/rustc_typeck/src/collect.rs
+++ b/compiler/rustc_typeck/src/collect.rs
@@ -1346,16 +1346,8 @@ fn has_late_bound_regions<'tcx>(tcx: TyCtxt<'tcx>, node: Node<'tcx>) -> Option<S
 
             match self.tcx.named_region(lt.hir_id) {
                 Some(rl::Region::Static | rl::Region::EarlyBound(..)) => {}
-                Some(
-                    rl::Region::LateBound(debruijn, _, _)
-                    | rl::Region::LateBoundAnon(debruijn, _, _),
-                ) if debruijn < self.outer_index => {}
-                Some(
-                    rl::Region::LateBound(..)
-                    | rl::Region::LateBoundAnon(..)
-                    | rl::Region::Free(..),
-                )
-                | None => {
+                Some(rl::Region::LateBound(debruijn, _, _)) if debruijn < self.outer_index => {}
+                Some(rl::Region::LateBound(..) | rl::Region::Free(..)) | None => {
                     self.has_late_bound_regions = Some(lt.span);
                 }
             }