Completely remove ConstnessAnd

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -31,7 +31,7 @@ use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::subst::{GenericArgKind, SubstsRef, UserSubsts};
 use rustc_middle::ty::{
     self, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations, OpaqueTypeKey, RegionVid,
-    ToPredicate, Ty, TyCtxt, UserType, UserTypeAnnotationIndex, WithConstness,
+    ToPredicate, Ty, TyCtxt, UserType, UserTypeAnnotationIndex,
 };
 use rustc_span::def_id::CRATE_DEF_ID;
 use rustc_span::{Span, DUMMY_SP};

compiler/rustc_infer/src/traits/engine.rs

@@ -2,7 +2,7 @@ use crate::infer::InferCtxt;
 use crate::traits::Obligation;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir::def_id::DefId;
-use rustc_middle::ty::{self, ToPredicate, Ty, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty};
 
 use super::FulfillmentError;
 use super::{ObligationCause, PredicateObligation};

compiler/rustc_infer/src/traits/util.rs

@@ -3,7 +3,7 @@ use smallvec::smallvec;
 use crate::infer::outlives::components::{push_outlives_components, Component};
 use crate::traits::{Obligation, ObligationCause, PredicateObligation};
 use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
-use rustc_middle::ty::{self, ToPredicate, TyCtxt, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, TyCtxt};
 use rustc_span::symbol::Ident;
 use rustc_span::Span;
 

compiler/rustc_middle/src/ty/mod.rs

@@ -846,20 +846,6 @@ impl ToPredicate<'tcx> for Binder<'tcx, PredicateKind<'tcx>> {
     }
 }
 
-impl<'tcx> ToPredicate<'tcx> for ConstnessAnd<PolyTraitRef<'tcx>> {
-    fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> {
-        self.value
-            .map_bound(|trait_ref| {
-                PredicateKind::Trait(ty::TraitPredicate {
-                    trait_ref,
-                    constness: self.constness,
-                    polarity: ty::ImplPolarity::Positive,
-                })
-            })
-            .to_predicate(tcx)
-    }
-}
-
 impl<'tcx> ToPredicate<'tcx> for PolyTraitPredicate<'tcx> {
     fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> {
         self.map_bound(PredicateKind::Trait).to_predicate(tcx)
@@ -1391,33 +1377,23 @@ impl<'tcx> ParamEnv<'tcx> {
     }
 }
 
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TypeFoldable)]
-pub struct ConstnessAnd<T> {
-    pub constness: BoundConstness,
-    pub value: T,
-}
-
 // FIXME(ecstaticmorse): Audit all occurrences of `without_const().to_predicate(tcx)` to ensure that
 // the constness of trait bounds is being propagated correctly.
-pub trait WithConstness: Sized {
+impl PolyTraitRef<'tcx> {
     #[inline]
-    fn with_constness(self, constness: BoundConstness) -> ConstnessAnd<Self> {
-        ConstnessAnd { constness, value: self }
+    pub fn with_constness(self, constness: BoundConstness) -> PolyTraitPredicate<'tcx> {
+        self.map_bound(|trait_ref| ty::TraitPredicate {
+            trait_ref,
+            constness,
+            polarity: ty::ImplPolarity::Positive,
+        })
     }
-
     #[inline]
-    fn with_const_if_const(self) -> ConstnessAnd<Self> {
-        self.with_constness(BoundConstness::ConstIfConst)
-    }
-
-    #[inline]
-    fn without_const(self) -> ConstnessAnd<Self> {
+    pub fn without_const(self) -> PolyTraitPredicate<'tcx> {
         self.with_constness(BoundConstness::NotConst)
     }
 }
 
-impl<T> WithConstness for T {}
-
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TypeFoldable)]
 pub struct ParamEnvAnd<'tcx, T> {
     pub param_env: ParamEnv<'tcx>,

compiler/rustc_middle/src/ty/relate.rs

@@ -218,19 +218,6 @@ impl<'tcx> Relate<'tcx> for ty::BoundConstness {
     }
 }
 
-impl<'tcx, T: Relate<'tcx>> Relate<'tcx> for ty::ConstnessAnd<T> {
-    fn relate<R: TypeRelation<'tcx>>(
-        relation: &mut R,
-        a: ty::ConstnessAnd<T>,
-        b: ty::ConstnessAnd<T>,
-    ) -> RelateResult<'tcx, ty::ConstnessAnd<T>> {
-        Ok(ty::ConstnessAnd {
-            constness: relation.relate(a.constness, b.constness)?,
-            value: relation.relate(a.value, b.value)?,
-        })
-    }
-}
-
 impl<'tcx> Relate<'tcx> for ast::Unsafety {
     fn relate<R: TypeRelation<'tcx>>(
         relation: &mut R,

compiler/rustc_middle/src/ty/sty.rs

@@ -8,9 +8,7 @@ use crate::infer::canonical::Canonical;
 use crate::ty::fold::ValidateBoundVars;
 use crate::ty::subst::{GenericArg, InternalSubsts, Subst, SubstsRef};
 use crate::ty::InferTy::{self, *};
-use crate::ty::{
-    self, AdtDef, DefIdTree, Discr, Ty, TyCtxt, TypeFlags, TypeFoldable, WithConstness,
-};
+use crate::ty::{self, AdtDef, DefIdTree, Discr, Ty, TyCtxt, TypeFlags, TypeFoldable};
 use crate::ty::{DelaySpanBugEmitted, List, ParamEnv, TyS};
 use polonius_engine::Atom;
 use rustc_data_structures::captures::Captures;

compiler/rustc_trait_selection/src/autoderef.rs

@@ -3,7 +3,7 @@ use crate::traits::{self, TraitEngine};
 use rustc_errors::struct_span_err;
 use rustc_hir as hir;
 use rustc_infer::infer::InferCtxt;
-use rustc_middle::ty::{self, TraitRef, Ty, TyCtxt, WithConstness};
+use rustc_middle::ty::{self, TraitRef, Ty, TyCtxt};
 use rustc_middle::ty::{ToPredicate, TypeFoldable};
 use rustc_session::{DiagnosticMessageId, Limit};
 use rustc_span::def_id::LOCAL_CRATE;

compiler/rustc_trait_selection/src/infer.rs

@@ -9,7 +9,6 @@ use rustc_middle::infer::canonical::{Canonical, CanonicalizedQueryResponse, Quer
 use rustc_middle::traits::query::Fallible;
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::ToPredicate;
-use rustc_middle::ty::WithConstness;
 use rustc_middle::ty::{self, Ty, TypeFoldable};
 use rustc_span::{Span, DUMMY_SP};
 

compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs

@@ -24,7 +24,7 @@ use rustc_middle::ty::error::ExpectedFound;
 use rustc_middle::ty::fold::TypeFolder;
 use rustc_middle::ty::{
     self, fast_reject, AdtKind, SubtypePredicate, ToPolyTraitRef, ToPredicate, Ty, TyCtxt,
-    TypeFoldable, WithConstness,
+    TypeFoldable,
 };
 use rustc_session::DiagnosticMessageId;
 use rustc_span::symbol::{kw, sym};

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -21,7 +21,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_hir::{AsyncGeneratorKind, GeneratorKind, Node};
 use rustc_middle::ty::{
     self, suggest_arbitrary_trait_bound, suggest_constraining_type_param, AdtKind, DefIdTree,
-    Infer, InferTy, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness,
+    Infer, InferTy, ToPredicate, Ty, TyCtxt, TypeFoldable,
 };
 use rustc_middle::ty::{TypeAndMut, TypeckResults};
 use rustc_session::Limit;

compiler/rustc_trait_selection/src/traits/mod.rs

@@ -33,8 +33,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::subst::{InternalSubsts, SubstsRef};
 use rustc_middle::ty::{
-    self, GenericParamDefKind, ToPredicate, Ty, TyCtxt, VtblEntry, WithConstness,
-    COMMON_VTABLE_ENTRIES,
+    self, GenericParamDefKind, ToPredicate, Ty, TyCtxt, VtblEntry, COMMON_VTABLE_ENTRIES,
 };
 use rustc_span::{sym, Span};
 use smallvec::SmallVec;

compiler/rustc_trait_selection/src/traits/object_safety.rs

@@ -18,7 +18,7 @@ use rustc_errors::FatalError;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::subst::{GenericArg, InternalSubsts, Subst};
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeVisitor, WithConstness};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeVisitor};
 use rustc_middle::ty::{Predicate, ToPredicate};
 use rustc_session::lint::builtin::WHERE_CLAUSES_OBJECT_SAFETY;
 use rustc_span::symbol::Symbol;

compiler/rustc_trait_selection/src/traits/project.rs

@@ -27,7 +27,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_infer::infer::resolve::OpportunisticRegionResolver;
 use rustc_middle::ty::fold::{TypeFoldable, TypeFolder};
 use rustc_middle::ty::subst::Subst;
-use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt};
 use rustc_span::symbol::sym;
 
 use std::collections::BTreeMap;

compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs

@@ -11,7 +11,7 @@ use rustc_infer::traits::TraitEngine;
 use rustc_infer::traits::{Obligation, SelectionError, TraitObligation};
 use rustc_lint_defs::builtin::DEREF_INTO_DYN_SUPERTRAIT;
 use rustc_middle::ty::print::with_no_trimmed_paths;
-use rustc_middle::ty::{self, ToPredicate, Ty, TypeFoldable, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty, TypeFoldable};
 use rustc_target::spec::abi::Abi;
 
 use crate::traits;

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -13,7 +13,7 @@ use rustc_infer::infer::InferOk;
 use rustc_infer::infer::LateBoundRegionConversionTime::HigherRankedType;
 use rustc_middle::ty::subst::{GenericArg, GenericArgKind, Subst, SubstsRef};
 use rustc_middle::ty::{self, Ty};
-use rustc_middle::ty::{ToPolyTraitRef, ToPredicate, WithConstness};
+use rustc_middle::ty::{ToPolyTraitRef, ToPredicate};
 use rustc_span::def_id::DefId;
 
 use crate::traits::project::{normalize_with_depth, normalize_with_depth_to};

compiler/rustc_trait_selection/src/traits/util.rs

@@ -6,7 +6,7 @@ use smallvec::SmallVec;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::subst::{GenericArg, Subst, SubstsRef};
-use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, TypeFoldable};
 
 use super::{Normalized, Obligation, ObligationCause, PredicateObligation, SelectionContext};
 pub use rustc_infer::traits::{self, util::*};

compiler/rustc_trait_selection/src/traits/wf.rs

@@ -6,7 +6,7 @@ use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::lang_items::LangItem;
 use rustc_middle::ty::subst::{GenericArg, GenericArgKind, SubstsRef};
-use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, TypeFoldable};
 use rustc_span::Span;
 
 use std::iter;

compiler/rustc_ty_utils/src/ty.rs

@@ -2,9 +2,7 @@ use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_middle::ty::subst::Subst;
-use rustc_middle::ty::{
-    self, Binder, Predicate, PredicateKind, ToPredicate, Ty, TyCtxt, WithConstness,
-};
+use rustc_middle::ty::{self, Binder, Predicate, PredicateKind, ToPredicate, Ty, TyCtxt};
 use rustc_span::Span;
 use rustc_trait_selection::traits;
 

compiler/rustc_typeck/src/bounds.rs

@@ -1,7 +1,7 @@
 //! Bounds are restrictions applied to some types after they've been converted into the
 //! `ty` form from the HIR.
 
-use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt};
 use rustc_span::Span;
 
 /// Collects together a list of type bounds. These lists of bounds occur in many places

compiler/rustc_typeck/src/check/method/mod.rs

@@ -22,7 +22,7 @@ use rustc_infer::infer::{self, InferOk};
 use rustc_middle::ty::subst::Subst;
 use rustc_middle::ty::subst::{InternalSubsts, SubstsRef};
 use rustc_middle::ty::GenericParamDefKind;
-use rustc_middle::ty::{self, ToPredicate, Ty, TypeFoldable, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty, TypeFoldable};
 use rustc_span::symbol::Ident;
 use rustc_span::Span;
 use rustc_trait_selection::traits;

compiler/rustc_typeck/src/check/method/probe.rs

@@ -21,7 +21,7 @@ use rustc_infer::infer::{self, InferOk, TyCtxtInferExt};
 use rustc_middle::middle::stability;
 use rustc_middle::ty::subst::{InternalSubsts, Subst, SubstsRef};
 use rustc_middle::ty::GenericParamDefKind;
-use rustc_middle::ty::{self, ParamEnvAnd, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
+use rustc_middle::ty::{self, ParamEnvAnd, ToPredicate, Ty, TyCtxt, TypeFoldable};
 use rustc_session::lint;
 use rustc_span::def_id::LocalDefId;
 use rustc_span::lev_distance::{find_best_match_for_name, lev_distance};

compiler/rustc_typeck/src/check/method/suggest.rs

@@ -12,7 +12,7 @@ use rustc_hir::{ExprKind, Node, QPath};
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_middle::ty::fast_reject::simplify_type;
 use rustc_middle::ty::print::with_crate_prefix;
-use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
+use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, TypeFoldable};
 use rustc_span::lev_distance;
 use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{source_map, FileName, MultiSpan, Span, Symbol};

compiler/rustc_typeck/src/check/wfcheck.rs

@@ -21,7 +21,6 @@ use rustc_middle::ty::subst::{GenericArgKind, InternalSubsts, Subst};
 use rustc_middle::ty::trait_def::TraitSpecializationKind;
 use rustc_middle::ty::{
     self, AdtKind, GenericParamDefKind, ToPredicate, Ty, TyCtxt, TypeFoldable, TypeVisitor,
-    WithConstness,
 };
 use rustc_session::parse::feature_err;
 use rustc_span::symbol::{sym, Ident, Symbol};

compiler/rustc_typeck/src/collect.rs

@@ -41,7 +41,7 @@ use rustc_middle::ty::subst::InternalSubsts;
 use rustc_middle::ty::util::Discr;
 use rustc_middle::ty::util::IntTypeExt;
 use rustc_middle::ty::{self, AdtKind, Const, DefIdTree, Ty, TyCtxt};
-use rustc_middle::ty::{ReprOptions, ToPredicate, WithConstness};
+use rustc_middle::ty::{ReprOptions, ToPredicate};
 use rustc_session::lint;
 use rustc_session::parse::feature_err;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};