Remove Partial/Ord from BoundRegion

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -1074,7 +1074,8 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             let (sig, reg) = ty::print::FmtPrinter::new(self.tcx, Namespace::TypeNS)
                 .name_all_regions(sig)
                 .unwrap();
-            let lts: Vec<String> = reg.into_values().map(|kind| kind.to_string()).collect();
+            let lts: Vec<String> =
+                reg.into_items().map(|(_, kind)| kind.to_string()).into_sorted_stable_ord();
             (if lts.is_empty() { String::new() } else { format!("for<{}> ", lts.join(", ")) }, sig)
         };
 

compiler/rustc_middle/src/ty/fold.rs

@@ -2,8 +2,6 @@ use crate::ty::{self, Binder, BoundTy, Ty, TyCtxt, TypeVisitableExt};
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_hir::def_id::DefId;
 
-use std::collections::BTreeMap;
-
 pub use rustc_type_ir::fold::{FallibleTypeFolder, TypeFoldable, TypeFolder, TypeSuperFoldable};
 
 ///////////////////////////////////////////////////////////////////////////
@@ -254,12 +252,12 @@ impl<'tcx> TyCtxt<'tcx> {
         self,
         value: Binder<'tcx, T>,
         mut fld_r: F,
-    ) -> (T, BTreeMap<ty::BoundRegion, ty::Region<'tcx>>)
+    ) -> (T, FxIndexMap<ty::BoundRegion, ty::Region<'tcx>>)
     where
         F: FnMut(ty::BoundRegion) -> ty::Region<'tcx>,
         T: TypeFoldable<TyCtxt<'tcx>>,
     {
-        let mut region_map = BTreeMap::new();
+        let mut region_map = FxIndexMap::default();
         let real_fld_r = |br: ty::BoundRegion| *region_map.entry(br).or_insert_with(|| fld_r(br));
         let value = self.instantiate_bound_regions_uncached(value, real_fld_r);
         (value, region_map)

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -10,6 +10,7 @@ use crate::ty::{
 use rustc_apfloat::ieee::{Double, Single};
 use rustc_apfloat::Float;
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
+use rustc_data_structures::unord::UnordMap;
 use rustc_hir as hir;
 use rustc_hir::def::{self, CtorKind, DefKind, Namespace};
 use rustc_hir::def_id::{DefIdMap, DefIdSet, ModDefId, CRATE_DEF_ID, LOCAL_CRATE};
@@ -24,7 +25,6 @@ use rustc_target::spec::abi::Abi;
 use smallvec::SmallVec;
 
 use std::cell::Cell;
-use std::collections::BTreeMap;
 use std::fmt::{self, Write as _};
 use std::iter;
 use std::ops::{Deref, DerefMut};
@@ -2537,7 +2537,7 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
 struct RegionFolder<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     current_index: ty::DebruijnIndex,
-    region_map: BTreeMap<ty::BoundRegion, ty::Region<'tcx>>,
+    region_map: UnordMap<ty::BoundRegion, ty::Region<'tcx>>,
     name: &'a mut (
                 dyn FnMut(
         Option<ty::DebruijnIndex>, // Debruijn index of the folded late-bound region
@@ -2614,7 +2614,7 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
     pub fn name_all_regions<T>(
         &mut self,
         value: &ty::Binder<'tcx, T>,
-    ) -> Result<(T, BTreeMap<ty::BoundRegion, ty::Region<'tcx>>), fmt::Error>
+    ) -> Result<(T, UnordMap<ty::BoundRegion, ty::Region<'tcx>>), fmt::Error>
     where
         T: Print<'tcx, Self> + TypeFoldable<TyCtxt<'tcx>>,
     {
@@ -2691,7 +2691,7 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
                 write!(self, "{var:?}")?;
             }
             start_or_continue(self, "", "> ");
-            (value.clone().skip_binder(), BTreeMap::default())
+            (value.clone().skip_binder(), UnordMap::default())
         } else {
             let tcx = self.tcx;
 
@@ -2763,7 +2763,7 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
                 tcx,
                 current_index: ty::INNERMOST,
                 name: &mut name,
-                region_map: BTreeMap::new(),
+                region_map: UnordMap::default(),
             };
             let new_value = value.clone().skip_binder().fold_with(&mut folder);
             let region_map = folder.region_map;

compiler/rustc_middle/src/ty/region.rs

@@ -358,7 +358,7 @@ impl Atom for RegionVid {
     }
 }
 
-#[derive(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, TyEncodable, TyDecodable, Copy)]
+#[derive(Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable, Copy)]
 #[derive(HashStable)]
 /// The parameter representation of late-bound function parameters, "some region
 /// at least as big as the scope `fr.scope`".
@@ -367,7 +367,7 @@ pub struct LateParamRegion {
     pub bound_region: BoundRegionKind,
 }
 
-#[derive(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, TyEncodable, TyDecodable, Copy)]
+#[derive(Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable, Copy)]
 #[derive(HashStable)]
 pub enum BoundRegionKind {
     /// An anonymous region parameter for a given fn (&T)
@@ -384,7 +384,7 @@ pub enum BoundRegionKind {
     BrEnv,
 }
 
-#[derive(Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable, PartialOrd, Ord)]
+#[derive(Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable)]
 #[derive(HashStable)]
 pub struct BoundRegion {
     pub var: BoundVar,

compiler/rustc_trait_selection/src/traits/util.rs

@@ -431,7 +431,7 @@ pub struct BoundVarReplacer<'me, 'tcx> {
     // These three maps track the bound variable that were replaced by placeholders. It might be
     // nice to remove these since we already have the `kind` in the placeholder; we really just need
     // the `var` (but we *could* bring that into scope if we were to track them as we pass them).
-    mapped_regions: BTreeMap<ty::PlaceholderRegion, ty::BoundRegion>,
+    mapped_regions: FxIndexMap<ty::PlaceholderRegion, ty::BoundRegion>,
     mapped_types: FxIndexMap<ty::PlaceholderType, ty::BoundTy>,
     mapped_consts: BTreeMap<ty::PlaceholderConst, ty::BoundVar>,
     // The current depth relative to *this* folding, *not* the entire normalization. In other words,
@@ -451,11 +451,12 @@ impl<'me, 'tcx> BoundVarReplacer<'me, 'tcx> {
         value: T,
     ) -> (
         T,
-        BTreeMap<ty::PlaceholderRegion, ty::BoundRegion>,
+        FxIndexMap<ty::PlaceholderRegion, ty::BoundRegion>,
         FxIndexMap<ty::PlaceholderType, ty::BoundTy>,
         BTreeMap<ty::PlaceholderConst, ty::BoundVar>,
     ) {
-        let mapped_regions: BTreeMap<ty::PlaceholderRegion, ty::BoundRegion> = BTreeMap::new();
+        let mapped_regions: FxIndexMap<ty::PlaceholderRegion, ty::BoundRegion> =
+            FxIndexMap::default();
         let mapped_types: FxIndexMap<ty::PlaceholderType, ty::BoundTy> = FxIndexMap::default();
         let mapped_consts: BTreeMap<ty::PlaceholderConst, ty::BoundVar> = BTreeMap::new();
 
@@ -574,7 +575,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for BoundVarReplacer<'_, 'tcx> {
 /// The inverse of [`BoundVarReplacer`]: replaces placeholders with the bound vars from which they came.
 pub struct PlaceholderReplacer<'me, 'tcx> {
     infcx: &'me InferCtxt<'tcx>,
-    mapped_regions: BTreeMap<ty::PlaceholderRegion, ty::BoundRegion>,
+    mapped_regions: FxIndexMap<ty::PlaceholderRegion, ty::BoundRegion>,
     mapped_types: FxIndexMap<ty::PlaceholderType, ty::BoundTy>,
     mapped_consts: BTreeMap<ty::PlaceholderConst, ty::BoundVar>,
     universe_indices: &'me [Option<ty::UniverseIndex>],
@@ -584,7 +585,7 @@ pub struct PlaceholderReplacer<'me, 'tcx> {
 impl<'me, 'tcx> PlaceholderReplacer<'me, 'tcx> {
     pub fn replace_placeholders<T: TypeFoldable<TyCtxt<'tcx>>>(
         infcx: &'me InferCtxt<'tcx>,
-        mapped_regions: BTreeMap<ty::PlaceholderRegion, ty::BoundRegion>,
+        mapped_regions: FxIndexMap<ty::PlaceholderRegion, ty::BoundRegion>,
         mapped_types: FxIndexMap<ty::PlaceholderType, ty::BoundTy>,
         mapped_consts: BTreeMap<ty::PlaceholderConst, ty::BoundVar>,
         universe_indices: &'me [Option<ty::UniverseIndex>],

tests/ui/anonymous-higher-ranked-lifetime.stderr

@@ -70,7 +70,7 @@ LL |     f4(|_: (), _: ()| {});
    |     |  found signature defined here
    |     expected due to this
    |
-   = note: expected closure signature `for<'r, 'a> fn(&'a (), &'r ()) -> _`
+   = note: expected closure signature `for<'a, 'r> fn(&'a (), &'r ()) -> _`
               found closure signature `fn((), ()) -> _`
 note: required by a bound in `f4`
   --> $DIR/anonymous-higher-ranked-lifetime.rs:19:25
@@ -217,7 +217,7 @@ LL |     h2(|_: (), _: (), _: (), _: ()| {});
    |     |  found signature defined here
    |     expected due to this
    |
-   = note: expected closure signature `for<'t0, 'a> fn(&'a (), Box<(dyn for<'a> Fn(&'a ()) + 'static)>, &'t0 (), for<'a, 'b> fn(&'a (), &'b ())) -> _`
+   = note: expected closure signature `for<'a, 't0> fn(&'a (), Box<(dyn for<'a> Fn(&'a ()) + 'static)>, &'t0 (), for<'a, 'b> fn(&'a (), &'b ())) -> _`
               found closure signature `fn((), (), (), ()) -> _`
 note: required by a bound in `h2`
   --> $DIR/anonymous-higher-ranked-lifetime.rs:30:25