Auto merge of #113303 - compiler-errors:yeet-chalk, r=lcnr

Remove chalk support from the compiler

Removes chalk (`-Ztrait-solver=chalk`) from the compiler and prunes any dead code resulting from this, mainly:
* Remove the chalk compatibility layer in `compiler/rustc_traits/src/chalk`
* Remove the chalk flag `-Ztrait-solver=chalk` and its `TraitEngine` implementation
* Remove `TypeWellFormedFromEnv` (and its many `bug!()` match arms)
* Remove the chalk migration mode from compiletest
* Remove the `chalkify` UI tests (do we want to keep any of these, but migrate them to `-Ztrait-solver=next`??)

Fulfills rust-lang/types-team#93.

r? `@jackh726`

89 files changed, 35 insertions, 3864 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 95db335ac52..cdf6a4cc2de 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -434,60 +434,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "chalk-derive"
-version = "0.92.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ff5053a8a42dbff5279a82423946fc56dc1253b76cf211b2b3c14b3aad4e1281"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.8",
- "synstructure 0.13.0",
-]
-
-[[package]]
-name = "chalk-engine"
-version = "0.92.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b9d0e18f29b8b0f4dcf7d31fe00c884af67719699e381e8dcc9d9624b1621c60"
-dependencies = [
- "chalk-derive",
- "chalk-ir",
- "chalk-solve",
- "rustc-hash",
- "tracing",
-]
-
-[[package]]
-name = "chalk-ir"
-version = "0.92.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a56de2146a8ed0fcd54f4bd50db852f1de4eac9e1efe568494f106c21b77d2a"
-dependencies = [
- "bitflags 1.3.2",
- "chalk-derive",
- "lazy_static",
-]
-
-[[package]]
-name = "chalk-solve"
-version = "0.92.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b392e02b4c81ec76d3748da839fc70a5539b83d27c9030668463d34d5110b860"
-dependencies = [
- "chalk-derive",
- "chalk-ir",
- "ena",
- "indexmap 1.9.3",
- "itertools",
- "petgraph",
- "rustc-hash",
- "tracing",
- "tracing-subscriber",
- "tracing-tree",
-]
-
-[[package]]
 name = "chrono"
 version = "0.4.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1169,12 +1115,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "fixedbitset"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37ab347416e802de484e4d03c7316c48f1ecb56574dfd4a46a80f173ce1de04d"
-
-[[package]]
 name = "flate2"
 version = "1.0.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2467,16 +2407,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "petgraph"
-version = "0.5.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "467d164a6de56270bd7c4d070df81d07beace25012d5103ced4e9ff08d6afdb7"
-dependencies = [
- "fixedbitset",
- "indexmap 1.9.3",
-]
-
-[[package]]
 name = "phf"
 version = "0.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -3675,7 +3605,6 @@ name = "rustc_middle"
 version = "0.0.0"
 dependencies = [
  "bitflags 1.3.2",
- "chalk-ir",
  "derive_more",
  "either",
  "field-offset",
@@ -4102,9 +4031,6 @@ dependencies = [
 name = "rustc_traits"
 version = "0.0.0"
 dependencies = [
- "chalk-engine",
- "chalk-ir",
- "chalk-solve",
  "rustc_ast",
  "rustc_data_structures",
  "rustc_hir",
@@ -5033,7 +4959,6 @@ dependencies = [
  "thread_local",
  "tracing",
  "tracing-core",
- "tracing-log",
 ]
 
 [[package]]
diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs
index 9b5ff3240ed..1d5e4ac55f8 100644
--- a/compiler/rustc_hir_analysis/src/astconv/mod.rs
+++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs
@@ -983,8 +983,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 ty::ClauseKind::RegionOutlives(_)
                 | ty::ClauseKind::ConstArgHasType(..)
                 | ty::ClauseKind::WellFormed(_)
-                | ty::ClauseKind::ConstEvaluatable(_)
-                | ty::ClauseKind::TypeWellFormedFromEnv(_) => {
+                | ty::ClauseKind::ConstEvaluatable(_) => {
                     bug!()
                 }
             }
diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
index 67800dbd2a2..c64fb469bb2 100644
--- a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
+++ b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
@@ -551,7 +551,6 @@ fn trait_predicate_kind<'tcx>(
         | ty::PredicateKind::ClosureKind(..)
         | ty::PredicateKind::Clause(ty::ClauseKind::ConstEvaluatable(..))
         | ty::PredicateKind::ConstEquate(..)
-        | ty::PredicateKind::Ambiguous
-        | ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => None,
+        | ty::PredicateKind::Ambiguous => None,
     }
 }
diff --git a/compiler/rustc_hir_analysis/src/outlives/explicit.rs b/compiler/rustc_hir_analysis/src/outlives/explicit.rs
index 3a04c3336ca..a7fca41f86a 100644
--- a/compiler/rustc_hir_analysis/src/outlives/explicit.rs
+++ b/compiler/rustc_hir_analysis/src/outlives/explicit.rs
@@ -53,8 +53,7 @@ impl<'tcx> ExplicitPredicatesMap<'tcx> {
                     | ty::ClauseKind::Projection(_)
                     | ty::ClauseKind::ConstArgHasType(_, _)
                     | ty::ClauseKind::WellFormed(_)
-                    | ty::ClauseKind::ConstEvaluatable(_)
-                    | ty::ClauseKind::TypeWellFormedFromEnv(_) => {}
+                    | ty::ClauseKind::ConstEvaluatable(_) => {}
                 }
             }
 
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
index d9d91b0f6be..adf1b8e351f 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
@@ -685,7 +685,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // inference variable.
                 | ty::PredicateKind::ClosureKind(..)
                 | ty::PredicateKind::Ambiguous
-                | ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => None,
+                 => None,
             },
         )
     }
diff --git a/compiler/rustc_hir_typeck/src/method/probe.rs b/compiler/rustc_hir_typeck/src/method/probe.rs
index 4c41fa38012..5e28ad5fd58 100644
--- a/compiler/rustc_hir_typeck/src/method/probe.rs
+++ b/compiler/rustc_hir_typeck/src/method/probe.rs
@@ -847,8 +847,7 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
                 | ty::ClauseKind::Projection(_)
                 | ty::ClauseKind::ConstArgHasType(_, _)
                 | ty::ClauseKind::WellFormed(_)
-                | ty::ClauseKind::ConstEvaluatable(_)
-                | ty::ClauseKind::TypeWellFormedFromEnv(_) => None,
+                | ty::ClauseKind::ConstEvaluatable(_) => None,
             }
         });
 
diff --git a/compiler/rustc_infer/src/infer/outlives/mod.rs b/compiler/rustc_infer/src/infer/outlives/mod.rs
index c998c923760..cb92fc6ddb6 100644
--- a/compiler/rustc_infer/src/infer/outlives/mod.rs
+++ b/compiler/rustc_infer/src/infer/outlives/mod.rs
@@ -31,8 +31,7 @@ pub fn explicit_outlives_bounds<'tcx>(
             | ty::ClauseKind::Projection(_)
             | ty::ClauseKind::ConstArgHasType(_, _)
             | ty::ClauseKind::WellFormed(_)
-            | ty::ClauseKind::ConstEvaluatable(_)
-            | ty::ClauseKind::TypeWellFormedFromEnv(_) => None,
+            | ty::ClauseKind::ConstEvaluatable(_) => None,
         })
 }
 
diff --git a/compiler/rustc_infer/src/traits/util.rs b/compiler/rustc_infer/src/traits/util.rs
index 66389cf5995..3aeed93baf2 100644
--- a/compiler/rustc_infer/src/traits/util.rs
+++ b/compiler/rustc_infer/src/traits/util.rs
@@ -370,9 +370,6 @@ impl<'tcx, O: Elaboratable<'tcx>> Elaborator<'tcx, O> {
                         }),
                 );
             }
-            ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                // Nothing to elaborate
-            }
             ty::PredicateKind::Ambiguous => {}
             ty::PredicateKind::AliasRelate(..) => {
                 // No
diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs
index 0f5dba1df14..09141afd137 100644
--- a/compiler/rustc_interface/src/tests.rs
+++ b/compiler/rustc_interface/src/tests.rs
@@ -841,7 +841,7 @@ fn test_unstable_options_tracking_hash() {
     tracked!(thir_unsafeck, true);
     tracked!(tiny_const_eval_limit, true);
     tracked!(tls_model, Some(TlsModel::GeneralDynamic));
-    tracked!(trait_solver, TraitSolver::Chalk);
+    tracked!(trait_solver, TraitSolver::NextCoherence);
     tracked!(translate_remapped_path_to_local_path, false);
     tracked!(trap_unreachable, Some(false));
     tracked!(treat_err_as_bug, NonZeroUsize::new(1));
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 3a177038ca8..c24760263bf 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -1606,8 +1606,7 @@ impl<'tcx> LateLintPass<'tcx> for TrivialConstraints {
                     // Ignore bounds that a user can't type
                     | ClauseKind::WellFormed(..)
                     // FIXME(generic_const_exprs): `ConstEvaluatable` can be written
-                    | ClauseKind::ConstEvaluatable(..)
-                    | ClauseKind::TypeWellFormedFromEnv(_)  => continue,
+                    | ClauseKind::ConstEvaluatable(..)  => continue,
                 };
                 if predicate.is_global() {
                     cx.emit_spanned_lint(
diff --git a/compiler/rustc_middle/Cargo.toml b/compiler/rustc_middle/Cargo.toml
index 07ab3ba4e8a..4c238308fe8 100644
--- a/compiler/rustc_middle/Cargo.toml
+++ b/compiler/rustc_middle/Cargo.toml
@@ -7,7 +7,6 @@ edition = "2021"
 
 [dependencies]
 bitflags = "1.2.1"
-chalk-ir = "0.92.0"
 derive_more = "0.99.17"
 either = "1.5.0"
 gsgdt = "0.1.2"
diff --git a/compiler/rustc_middle/src/query/erase.rs b/compiler/rustc_middle/src/query/erase.rs
index e8f4fca147b..2c481745d98 100644
--- a/compiler/rustc_middle/src/query/erase.rs
+++ b/compiler/rustc_middle/src/query/erase.rs
@@ -315,7 +315,6 @@ tcx_lifetime! {
     rustc_middle::mir::interpret::ConstValue,
     rustc_middle::mir::interpret::GlobalId,
     rustc_middle::mir::interpret::LitToConstInput,
-    rustc_middle::traits::ChalkEnvironmentAndGoal,
     rustc_middle::traits::query::MethodAutoderefStepsResult,
     rustc_middle::traits::query::type_op::AscribeUserType,
     rustc_middle::traits::query::type_op::Eq,
diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
index a8cdf8286fe..6f942e0bc86 100644
--- a/compiler/rustc_middle/src/query/mod.rs
+++ b/compiler/rustc_middle/src/query/mod.rs
@@ -39,8 +39,8 @@ use crate::traits::query::{
 };
 use crate::traits::specialization_graph;
 use crate::traits::{
-    CanonicalChalkEnvironmentAndGoal, CodegenObligationError, EvaluationResult, ImplSource,
-    ObjectSafetyViolation, ObligationCause, OverflowError, WellFormedLoc,
+    CodegenObligationError, EvaluationResult, ImplSource, ObjectSafetyViolation, ObligationCause,
+    OverflowError, WellFormedLoc,
 };
 use crate::ty::fast_reject::SimplifiedType;
 use crate::ty::layout::ValidityRequirement;
@@ -1971,15 +1971,6 @@ rustc_queries! {
         desc { "evaluating trait selection obligation `{}`", goal.value.value }
     }
 
-    query evaluate_goal(
-        goal: CanonicalChalkEnvironmentAndGoal<'tcx>
-    ) -> Result<
-        &'tcx Canonical<'tcx, canonical::QueryResponse<'tcx, ()>>,
-        NoSolution
-    > {
-        desc { "evaluating trait selection obligation `{}`", goal.value }
-    }
-
     /// Do not call this query directly: part of the `Eq` type-op
     query type_op_ascribe_user_type(
         goal: CanonicalTypeOpAscribeUserTypeGoal<'tcx>
diff --git a/compiler/rustc_middle/src/traits/chalk.rs b/compiler/rustc_middle/src/traits/chalk.rs
deleted file mode 100644
index 6e3d2d91ae9..00000000000
--- a/compiler/rustc_middle/src/traits/chalk.rs
+++ /dev/null
@@ -1,396 +0,0 @@
-//! Types required for Chalk-related queries
-//!
-//! The primary purpose of this file is defining an implementation for the
-//! `chalk_ir::interner::Interner` trait. The primary purpose of this trait, as
-//! its name suggest, is to provide an abstraction boundary for creating
-//! interned Chalk types.
-
-use rustc_middle::ty::{self, AdtDef, TyCtxt};
-
-use rustc_hir::def_id::DefId;
-use rustc_target::spec::abi::Abi;
-
-use std::cmp::Ordering;
-use std::fmt;
-use std::hash::{Hash, Hasher};
-
-#[derive(Copy, Clone)]
-pub struct RustInterner<'tcx> {
-    pub tcx: TyCtxt<'tcx>,
-}
-
-/// We don't ever actually need this. It's only required for derives.
-impl<'tcx> Hash for RustInterner<'tcx> {
-    fn hash<H: Hasher>(&self, _state: &mut H) {}
-}
-
-/// We don't ever actually need this. It's only required for derives.
-impl<'tcx> Ord for RustInterner<'tcx> {
-    fn cmp(&self, _other: &Self) -> Ordering {
-        Ordering::Equal
-    }
-}
-
-/// We don't ever actually need this. It's only required for derives.
-impl<'tcx> PartialOrd for RustInterner<'tcx> {
-    fn partial_cmp(&self, _other: &Self) -> Option<Ordering> {
-        None
-    }
-}
-
-/// We don't ever actually need this. It's only required for derives.
-impl<'tcx> PartialEq for RustInterner<'tcx> {
-    fn eq(&self, _other: &Self) -> bool {
-        false
-    }
-}
-
-/// We don't ever actually need this. It's only required for derives.
-impl<'tcx> Eq for RustInterner<'tcx> {}
-
-impl fmt::Debug for RustInterner<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "RustInterner")
-    }
-}
-
-// Right now, there is no interning at all. I was running into problems with
-// adding interning in `ty/context.rs` for Chalk types with
-// `parallel-compiler = true`. -jackh726
-impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
-    type InternedType = Box<chalk_ir::TyData<Self>>;
-    type InternedLifetime = Box<chalk_ir::LifetimeData<Self>>;
-    type InternedConst = Box<chalk_ir::ConstData<Self>>;
-    type InternedConcreteConst = ty::ValTree<'tcx>;
-    type InternedGenericArg = Box<chalk_ir::GenericArgData<Self>>;
-    type InternedGoal = Box<chalk_ir::GoalData<Self>>;
-    type InternedGoals = Vec<chalk_ir::Goal<Self>>;
-    type InternedSubstitution = Vec<chalk_ir::GenericArg<Self>>;
-    type InternedProgramClause = Box<chalk_ir::ProgramClauseData<Self>>;
-    type InternedProgramClauses = Vec<chalk_ir::ProgramClause<Self>>;
-    type InternedQuantifiedWhereClauses = Vec<chalk_ir::QuantifiedWhereClause<Self>>;
-    type InternedVariableKinds = Vec<chalk_ir::VariableKind<Self>>;
-    type InternedCanonicalVarKinds = Vec<chalk_ir::CanonicalVarKind<Self>>;
-    type InternedVariances = Vec<chalk_ir::Variance>;
-    type InternedConstraints = Vec<chalk_ir::InEnvironment<chalk_ir::Constraint<Self>>>;
-    type DefId = DefId;
-    type InternedAdtId = AdtDef<'tcx>;
-    type Identifier = ();
-    type FnAbi = Abi;
-
-    fn debug_program_clause_implication(
-        pci: &chalk_ir::ProgramClauseImplication<Self>,
-        fmt: &mut fmt::Formatter<'_>,
-    ) -> Option<fmt::Result> {
-        let mut write = || {
-            write!(fmt, "{:?}", pci.consequence)?;
-
-            let conditions = pci.conditions.interned();
-            let constraints = pci.constraints.interned();
-
-            let conds = conditions.len();
-            let consts = constraints.len();
-            if conds == 0 && consts == 0 {
-                return Ok(());
-            }
-
-            write!(fmt, " :- ")?;
-
-            if conds != 0 {
-                for cond in &conditions[..conds - 1] {
-                    write!(fmt, "{:?}, ", cond)?;
-                }
-                write!(fmt, "{:?}", conditions[conds - 1])?;
-            }
-
-            if conds != 0 && consts != 0 {
-                write!(fmt, " ; ")?;
-            }
-
-            if consts != 0 {
-                for constraint in &constraints[..consts - 1] {
-                    write!(fmt, "{:?}, ", constraint)?;
-                }
-                write!(fmt, "{:?}", constraints[consts - 1])?;
-            }
-
-            Ok(())
-        };
-        Some(write())
-    }
-
-    fn debug_substitution(
-        substitution: &chalk_ir::Substitution<Self>,
-        fmt: &mut fmt::Formatter<'_>,
-    ) -> Option<fmt::Result> {
-        Some(write!(fmt, "{:?}", substitution.interned()))
-    }
-
-    fn debug_separator_trait_ref(
-        separator_trait_ref: &chalk_ir::SeparatorTraitRef<'_, Self>,
-        fmt: &mut fmt::Formatter<'_>,
-    ) -> Option<fmt::Result> {
-        let substitution = &separator_trait_ref.trait_ref.substitution;
-        let parameters = substitution.interned();
-        Some(write!(
-            fmt,
-            "{:?}{}{:?}{:?}",
-            parameters[0],
-            separator_trait_ref.separator,
-            separator_trait_ref.trait_ref.trait_id,
-            chalk_ir::debug::Angle(&parameters[1..])
-        ))
-    }
-
-    fn debug_quantified_where_clauses(
-        clauses: &chalk_ir::QuantifiedWhereClauses<Self>,
-        fmt: &mut fmt::Formatter<'_>,
-    ) -> Option<fmt::Result> {
-        Some(write!(fmt, "{:?}", clauses.interned()))
-    }
-
-    fn debug_ty(ty: &chalk_ir::Ty<Self>, fmt: &mut fmt::Formatter<'_>) -> Option<fmt::Result> {
-        match &ty.interned().kind {
-            chalk_ir::TyKind::Ref(chalk_ir::Mutability::Not, lifetime, ty) => {
-                Some(write!(fmt, "(&{:?} {:?})", lifetime, ty))
-            }
-            chalk_ir::TyKind::Ref(chalk_ir::Mutability::Mut, lifetime, ty) => {
-                Some(write!(fmt, "(&{:?} mut {:?})", lifetime, ty))
-            }
-            chalk_ir::TyKind::Array(ty, len) => Some(write!(fmt, "[{:?}; {:?}]", ty, len)),
-            chalk_ir::TyKind::Slice(ty) => Some(write!(fmt, "[{:?}]", ty)),
-            chalk_ir::TyKind::Tuple(len, substs) => Some(
-                try {
-                    write!(fmt, "(")?;
-                    for (idx, substitution) in substs.interned().iter().enumerate() {
-                        if idx == *len && *len != 1 {
-                            // Don't add a trailing comma if the tuple has more than one element
-                            write!(fmt, "{:?}", substitution)?;
-                        } else {
-                            write!(fmt, "{:?},", substitution)?;
-                        }
-                    }
-                    write!(fmt, ")")?;
-                },
-            ),
-            _ => None,
-        }
-    }
-
-    fn debug_alias(
-        alias_ty: &chalk_ir::AliasTy<Self>,
-        fmt: &mut fmt::Formatter<'_>,
-    ) -> Option<fmt::Result> {
-        match alias_ty {
-            chalk_ir::AliasTy::Projection(projection_ty) => {
-                Self::debug_projection_ty(projection_ty, fmt)
-            }
-            chalk_ir::AliasTy::Opaque(opaque_ty) => Self::debug_opaque_ty(opaque_ty, fmt),
-        }
-    }
-
-    fn debug_projection_ty(
-        projection_ty: &chalk_ir::ProjectionTy<Self>,
-        fmt: &mut fmt::Formatter<'_>,
-    ) -> Option<fmt::Result> {
-        Some(write!(
-            fmt,
-            "projection: {:?} {:?}",
-            projection_ty.associated_ty_id, projection_ty.substitution,
-        ))
-    }
-
-    fn debug_opaque_ty(
-        opaque_ty: &chalk_ir::OpaqueTy<Self>,
-        fmt: &mut fmt::Formatter<'_>,
-    ) -> Option<fmt::Result> {
-        Some(write!(fmt, "{:?}", opaque_ty.opaque_ty_id))
-    }
-
-    fn intern_ty(self, ty: chalk_ir::TyKind<Self>) -> Self::InternedType {
-        let flags = ty.compute_flags(self);
-        Box::new(chalk_ir::TyData { kind: ty, flags: flags })
-    }
-
-    fn ty_data(self, ty: &Self::InternedType) -> &chalk_ir::TyData<Self> {
-        ty
-    }
-
-    fn intern_lifetime(self, lifetime: chalk_ir::LifetimeData<Self>) -> Self::InternedLifetime {
-        Box::new(lifetime)
-    }
-
-    fn lifetime_data(self, lifetime: &Self::InternedLifetime) -> &chalk_ir::LifetimeData<Self> {
-        &lifetime
-    }
-
-    fn intern_const(self, constant: chalk_ir::ConstData<Self>) -> Self::InternedConst {
-        Box::new(constant)
-    }
-
-    fn const_data(self, constant: &Self::InternedConst) -> &chalk_ir::ConstData<Self> {
-        &constant
-    }
-
-    fn const_eq(
-        self,
-        _ty: &Self::InternedType,
-        c1: &Self::InternedConcreteConst,
-        c2: &Self::InternedConcreteConst,
-    ) -> bool {
-        c1 == c2
-    }
-
-    fn intern_generic_arg(self, data: chalk_ir::GenericArgData<Self>) -> Self::InternedGenericArg {
-        Box::new(data)
-    }
-
-    fn generic_arg_data(self, data: &Self::InternedGenericArg) -> &chalk_ir::GenericArgData<Self> {
-        &data
-    }
-
-    fn intern_goal(self, goal: chalk_ir::GoalData<Self>) -> Self::InternedGoal {
-        Box::new(goal)
-    }
-
-    fn goal_data(self, goal: &Self::InternedGoal) -> &chalk_ir::GoalData<Self> {
-        &goal
-    }
-
-    fn intern_goals<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::Goal<Self>, E>>,
-    ) -> Result<Self::InternedGoals, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn goals_data(self, goals: &Self::InternedGoals) -> &[chalk_ir::Goal<Self>] {
-        goals
-    }
-
-    fn intern_substitution<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::GenericArg<Self>, E>>,
-    ) -> Result<Self::InternedSubstitution, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn substitution_data(
-        self,
-        substitution: &Self::InternedSubstitution,
-    ) -> &[chalk_ir::GenericArg<Self>] {
-        substitution
-    }
-
-    fn intern_program_clause(
-        self,
-        data: chalk_ir::ProgramClauseData<Self>,
-    ) -> Self::InternedProgramClause {
-        Box::new(data)
-    }
-
-    fn program_clause_data(
-        self,
-        clause: &Self::InternedProgramClause,
-    ) -> &chalk_ir::ProgramClauseData<Self> {
-        &clause
-    }
-
-    fn intern_program_clauses<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::ProgramClause<Self>, E>>,
-    ) -> Result<Self::InternedProgramClauses, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn program_clauses_data(
-        self,
-        clauses: &Self::InternedProgramClauses,
-    ) -> &[chalk_ir::ProgramClause<Self>] {
-        clauses
-    }
-
-    fn intern_quantified_where_clauses<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::QuantifiedWhereClause<Self>, E>>,
-    ) -> Result<Self::InternedQuantifiedWhereClauses, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn quantified_where_clauses_data(
-        self,
-        clauses: &Self::InternedQuantifiedWhereClauses,
-    ) -> &[chalk_ir::QuantifiedWhereClause<Self>] {
-        clauses
-    }
-
-    fn intern_generic_arg_kinds<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::VariableKind<Self>, E>>,
-    ) -> Result<Self::InternedVariableKinds, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn variable_kinds_data(
-        self,
-        parameter_kinds: &Self::InternedVariableKinds,
-    ) -> &[chalk_ir::VariableKind<Self>] {
-        parameter_kinds
-    }
-
-    fn intern_canonical_var_kinds<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::CanonicalVarKind<Self>, E>>,
-    ) -> Result<Self::InternedCanonicalVarKinds, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn canonical_var_kinds_data(
-        self,
-        canonical_var_kinds: &Self::InternedCanonicalVarKinds,
-    ) -> &[chalk_ir::CanonicalVarKind<Self>] {
-        canonical_var_kinds
-    }
-
-    fn intern_constraints<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::InEnvironment<chalk_ir::Constraint<Self>>, E>>,
-    ) -> Result<Self::InternedConstraints, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn constraints_data(
-        self,
-        constraints: &Self::InternedConstraints,
-    ) -> &[chalk_ir::InEnvironment<chalk_ir::Constraint<Self>>] {
-        constraints
-    }
-
-    fn intern_variances<E>(
-        self,
-        data: impl IntoIterator<Item = Result<chalk_ir::Variance, E>>,
-    ) -> Result<Self::InternedVariances, E> {
-        data.into_iter().collect::<Result<Vec<_>, _>>()
-    }
-
-    fn variances_data(self, variances: &Self::InternedVariances) -> &[chalk_ir::Variance] {
-        variances
-    }
-}
-
-impl<'tcx> chalk_ir::interner::HasInterner for RustInterner<'tcx> {
-    type Interner = Self;
-}
-
-/// A chalk environment and goal.
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, HashStable, TypeFoldable, TypeVisitable)]
-pub struct ChalkEnvironmentAndGoal<'tcx> {
-    pub environment: &'tcx ty::List<ty::Clause<'tcx>>,
-    pub goal: ty::Predicate<'tcx>,
-}
-
-impl<'tcx> fmt::Display for ChalkEnvironmentAndGoal<'tcx> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "environment: {:?}, goal: {}", self.environment, self.goal)
-    }
-}
diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs
index a333fbbb506..69d826bbe7a 100644
--- a/compiler/rustc_middle/src/traits/mod.rs
+++ b/compiler/rustc_middle/src/traits/mod.rs
@@ -2,7 +2,6 @@
 //!
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/traits/resolution.html
 
-mod chalk;
 pub mod query;
 pub mod select;
 pub mod solve;
@@ -30,12 +29,8 @@ use std::hash::{Hash, Hasher};
 
 pub use self::select::{EvaluationCache, EvaluationResult, OverflowError, SelectionCache};
 
-pub type CanonicalChalkEnvironmentAndGoal<'tcx> = Canonical<'tcx, ChalkEnvironmentAndGoal<'tcx>>;
-
 pub use self::ObligationCauseCode::*;
 
-pub use self::chalk::{ChalkEnvironmentAndGoal, RustInterner as ChalkRustInterner};
-
 /// Depending on the stage of compilation, we want projection to be
 /// more or less conservative.
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash, HashStable, Encodable, Decodable)]
diff --git a/compiler/rustc_middle/src/ty/flags.rs b/compiler/rustc_middle/src/ty/flags.rs
index 06a8e34cbab..ff391794703 100644
--- a/compiler/rustc_middle/src/ty/flags.rs
+++ b/compiler/rustc_middle/src/ty/flags.rs
@@ -287,9 +287,6 @@ impl FlagComputation {
                 self.add_const(expected);
                 self.add_const(found);
             }
-            ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(ty)) => {
-                self.add_ty(ty);
-            }
             ty::PredicateKind::Ambiguous => {}
             ty::PredicateKind::AliasRelate(t1, t2, _) => {
                 self.add_term(t1);
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index 7bd49ad07ea..48388be2f46 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -554,8 +554,7 @@ impl<'tcx> Predicate<'tcx> {
             | PredicateKind::Coerce(_)
             | PredicateKind::Clause(ClauseKind::ConstEvaluatable(_))
             | PredicateKind::ConstEquate(_, _)
-            | PredicateKind::Ambiguous
-            | PredicateKind::Clause(ClauseKind::TypeWellFormedFromEnv(_)) => true,
+            | PredicateKind::Ambiguous => true,
         }
     }
 }
@@ -661,11 +660,6 @@ pub enum ClauseKind<'tcx> {
 
     /// Constant initializer must evaluate successfully.
     ConstEvaluatable(ty::Const<'tcx>),
-
-    /// Represents a type found in the environment that we can use for implied bounds.
-    ///
-    /// Only used for Chalk.
-    TypeWellFormedFromEnv(Ty<'tcx>),
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, Hash, TyEncodable, TyDecodable)]
@@ -1424,8 +1418,7 @@ impl<'tcx> Predicate<'tcx> {
             | PredicateKind::Clause(ClauseKind::TypeOutlives(..))
             | PredicateKind::Clause(ClauseKind::ConstEvaluatable(..))
             | PredicateKind::ConstEquate(..)
-            | PredicateKind::Ambiguous
-            | PredicateKind::Clause(ClauseKind::TypeWellFormedFromEnv(..)) => None,
+            | PredicateKind::Ambiguous => None,
         }
     }
 
@@ -1445,8 +1438,7 @@ impl<'tcx> Predicate<'tcx> {
             | PredicateKind::Clause(ClauseKind::TypeOutlives(..))
             | PredicateKind::Clause(ClauseKind::ConstEvaluatable(..))
             | PredicateKind::ConstEquate(..)
-            | PredicateKind::Ambiguous
-            | PredicateKind::Clause(ClauseKind::TypeWellFormedFromEnv(..)) => None,
+            | PredicateKind::Ambiguous => None,
         }
     }
 
@@ -1466,8 +1458,7 @@ impl<'tcx> Predicate<'tcx> {
             | PredicateKind::ClosureKind(..)
             | PredicateKind::Clause(ClauseKind::ConstEvaluatable(..))
             | PredicateKind::ConstEquate(..)
-            | PredicateKind::Ambiguous
-            | PredicateKind::Clause(ClauseKind::TypeWellFormedFromEnv(..)) => None,
+            | PredicateKind::Ambiguous => None,
         }
     }
 
diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs
index dcc8247937d..f912ff04496 100644
--- a/compiler/rustc_middle/src/ty/print/pretty.rs
+++ b/compiler/rustc_middle/src/ty/print/pretty.rs
@@ -2888,9 +2888,6 @@ define_print_and_forward_display! {
             ty::ClauseKind::ConstEvaluatable(ct) => {
                 p!("the constant `", print(ct), "` can be evaluated")
             }
-            ty::ClauseKind::TypeWellFormedFromEnv(ty) => {
-                p!("the type `", print(ty), "` is found in the environment")
-            }
         }
     }
 
diff --git a/compiler/rustc_middle/src/ty/structural_impls.rs b/compiler/rustc_middle/src/ty/structural_impls.rs
index 113328de176..f195b062a62 100644
--- a/compiler/rustc_middle/src/ty/structural_impls.rs
+++ b/compiler/rustc_middle/src/ty/structural_impls.rs
@@ -189,9 +189,6 @@ impl<'tcx> fmt::Debug for ty::ClauseKind<'tcx> {
             ty::ClauseKind::ConstEvaluatable(ct) => {
                 write!(f, "ConstEvaluatable({ct:?})")
             }
-            ty::ClauseKind::TypeWellFormedFromEnv(ty) => {
-                write!(f, "TypeWellFormedFromEnv({:?})", ty)
-            }
         }
     }
 }
diff --git a/compiler/rustc_privacy/src/lib.rs b/compiler/rustc_privacy/src/lib.rs
index 055006373ef..4fcee9396ed 100644
--- a/compiler/rustc_privacy/src/lib.rs
+++ b/compiler/rustc_privacy/src/lib.rs
@@ -174,7 +174,6 @@ where
             }
             ty::ClauseKind::ConstEvaluatable(ct) => ct.visit_with(self),
             ty::ClauseKind::WellFormed(arg) => arg.visit_with(self),
-            ty::ClauseKind::TypeWellFormedFromEnv(_) => bug!("unexpected clause: {clause}"),
         }
     }
 
diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index 2fe7a6f511b..43846e65bca 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -737,8 +737,6 @@ pub enum PrintRequest {
 pub enum TraitSolver {
     /// Classic trait solver in `rustc_trait_selection::traits::select`
     Classic,
-    /// Chalk trait solver
-    Chalk,
     /// Experimental trait solver in `rustc_trait_selection::solve`
     Next,
     /// Use the new trait solver during coherence
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index 16a4c2a8b3d..05d3e71074a 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -386,7 +386,7 @@ mod desc {
     pub const parse_unpretty: &str = "`string` or `string=string`";
     pub const parse_treat_err_as_bug: &str = "either no value or a number bigger than 0";
     pub const parse_trait_solver: &str =
-        "one of the supported solver modes (`classic`, `chalk`, or `next`)";
+        "one of the supported solver modes (`classic`, `next`, or `next-coherence`)";
     pub const parse_lto: &str =
         "either a boolean (`yes`, `no`, `on`, `off`, etc), `thin`, `fat`, or omitted";
     pub const parse_linker_plugin_lto: &str =
@@ -983,7 +983,6 @@ mod parse {
     pub(crate) fn parse_trait_solver(slot: &mut TraitSolver, v: Option<&str>) -> bool {
         match v {
             Some("classic") => *slot = TraitSolver::Classic,
-            Some("chalk") => *slot = TraitSolver::Chalk,
             Some("next") => *slot = TraitSolver::Next,
             Some("next-coherence") => *slot = TraitSolver::NextCoherence,
             // default trait solver is subject to change..
diff --git a/compiler/rustc_trait_selection/src/solve/eval_ctxt.rs b/compiler/rustc_trait_selection/src/solve/eval_ctxt.rs
index 3b0c5849099..6b7be73b631 100644
--- a/compiler/rustc_trait_selection/src/solve/eval_ctxt.rs
+++ b/compiler/rustc_trait_selection/src/solve/eval_ctxt.rs
@@ -435,9 +435,6 @@ impl<'a, 'tcx> EvalCtxt<'a, 'tcx> {
                 ty::PredicateKind::ConstEquate(_, _) => {
                     bug!("ConstEquate should not be emitted when `-Ztrait-solver=next` is active")
                 }
-                ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                    bug!("TypeWellFormedFromEnv is only used for Chalk")
-                }
                 ty::PredicateKind::AliasRelate(lhs, rhs, direction) => self
                     .compute_alias_relate_goal(Goal {
                         param_env,
diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
index fb6bf7211b9..cb42281152d 100644
--- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs
+++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
@@ -836,9 +836,6 @@ impl<'tcx> AutoTraitFinder<'tcx> {
                 // FIXME(generic_const_exprs): you can absolutely add this as a where clauses
                 | ty::PredicateKind::Clause(ty::ClauseKind::ConstEvaluatable(..))
                 | ty::PredicateKind::Coerce(..) => {}
-                ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                    bug!("predicate should only exist in the environment: {bound_predicate:?}")
-                }
                 ty::PredicateKind::Ambiguous => return false,
             };
         }
diff --git a/compiler/rustc_trait_selection/src/traits/chalk_fulfill.rs b/compiler/rustc_trait_selection/src/traits/chalk_fulfill.rs
deleted file mode 100644
index 3ecae429c59..00000000000
--- a/compiler/rustc_trait_selection/src/traits/chalk_fulfill.rs
+++ /dev/null
@@ -1,149 +0,0 @@
-//! Defines a Chalk-based `TraitEngine`
-
-use crate::infer::canonical::OriginalQueryValues;
-use crate::infer::InferCtxt;
-use crate::traits::query::NoSolution;
-use crate::traits::{
-    ChalkEnvironmentAndGoal, FulfillmentError, FulfillmentErrorCode, PredicateObligation,
-    SelectionError, TraitEngine,
-};
-use rustc_data_structures::fx::FxIndexSet;
-use rustc_middle::ty::TypeVisitableExt;
-
-pub struct FulfillmentContext<'tcx> {
-    obligations: FxIndexSet<PredicateObligation<'tcx>>,
-
-    /// The snapshot in which this context was created. Using the context
-    /// outside of this snapshot leads to subtle bugs if the snapshot
-    /// gets rolled back. Because of this we explicitly check that we only
-    /// use the context in exactly this snapshot.
-    usable_in_snapshot: usize,
-}
-
-impl<'tcx> FulfillmentContext<'tcx> {
-    pub(super) fn new(infcx: &InferCtxt<'tcx>) -> Self {
-        FulfillmentContext {
-            obligations: FxIndexSet::default(),
-            usable_in_snapshot: infcx.num_open_snapshots(),
-        }
-    }
-}
-
-impl<'tcx> TraitEngine<'tcx> for FulfillmentContext<'tcx> {
-    fn register_predicate_obligation(
-        &mut self,
-        infcx: &InferCtxt<'tcx>,
-        obligation: PredicateObligation<'tcx>,
-    ) {
-        assert_eq!(self.usable_in_snapshot, infcx.num_open_snapshots());
-        let obligation = infcx.resolve_vars_if_possible(obligation);
-
-        self.obligations.insert(obligation);
-    }
-
-    fn collect_remaining_errors(
-        &mut self,
-        _infcx: &InferCtxt<'tcx>,
-    ) -> Vec<FulfillmentError<'tcx>> {
-        // any remaining obligations are errors
-        self.obligations
-            .iter()
-            .map(|obligation| FulfillmentError {
-                obligation: obligation.clone(),
-                code: FulfillmentErrorCode::CodeAmbiguity { overflow: false },
-                // FIXME - does Chalk have a notation of 'root obligation'?
-                // This is just for diagnostics, so it's okay if this is wrong
-                root_obligation: obligation.clone(),
-            })
-            .collect()
-    }
-
-    fn select_where_possible(&mut self, infcx: &InferCtxt<'tcx>) -> Vec<FulfillmentError<'tcx>> {
-        assert_eq!(self.usable_in_snapshot, infcx.num_open_snapshots());
-
-        let mut errors = Vec::new();
-        let mut next_round = FxIndexSet::default();
-        let mut making_progress;
-
-        loop {
-            making_progress = false;
-
-            // We iterate over all obligations, and record if we are able
-            // to unambiguously prove at least one obligation.
-            for obligation in self.obligations.drain(..) {
-                let obligation = infcx.resolve_vars_if_possible(obligation);
-                let environment = obligation.param_env.caller_bounds();
-                let goal = ChalkEnvironmentAndGoal { environment, goal: obligation.predicate };
-                let mut orig_values = OriginalQueryValues::default();
-                if goal.references_error() {
-                    continue;
-                }
-
-                let canonical_goal =
-                    infcx.canonicalize_query_preserving_universes(goal, &mut orig_values);
-
-                match infcx.tcx.evaluate_goal(canonical_goal) {
-                    Ok(response) => {
-                        if response.is_proven() {
-                            making_progress = true;
-
-                            match infcx.instantiate_query_response_and_region_obligations(
-                                &obligation.cause,
-                                obligation.param_env,
-                                &orig_values,
-                                &response,
-                            ) {
-                                Ok(infer_ok) => {
-                                    next_round.extend(infer_ok.obligations.into_iter().map(
-                                        |obligation| infcx.resolve_vars_if_possible(obligation),
-                                    ))
-                                }
-
-                                Err(_err) => errors.push(FulfillmentError {
-                                    obligation: obligation.clone(),
-                                    code: FulfillmentErrorCode::CodeSelectionError(
-                                        SelectionError::Unimplemented,
-                                    ),
-                                    // FIXME - does Chalk have a notation of 'root obligation'?
-                                    // This is just for diagnostics, so it's okay if this is wrong
-                                    root_obligation: obligation,
-                                }),
-                            }
-                        } else {
-                            // Ambiguous: retry at next round.
-                            next_round.insert(obligation);
-                        }
-                    }
-
-                    Err(NoSolution) => errors.push(FulfillmentError {
-                        obligation: obligation.clone(),
-                        code: FulfillmentErrorCode::CodeSelectionError(
-                            SelectionError::Unimplemented,
-                        ),
-                        // FIXME - does Chalk have a notation of 'root obligation'?
-                        // This is just for diagnostics, so it's okay if this is wrong
-                        root_obligation: obligation,
-                    }),
-                }
-            }
-            next_round = std::mem::replace(&mut self.obligations, next_round);
-
-            if !making_progress {
-                break;
-            }
-        }
-
-        errors
-    }
-
-    fn drain_unstalled_obligations(
-        &mut self,
-        _: &InferCtxt<'tcx>,
-    ) -> Vec<PredicateObligation<'tcx>> {
-        unimplemented!()
-    }
-
-    fn pending_obligations(&self) -> Vec<PredicateObligation<'tcx>> {
-        self.obligations.iter().cloned().collect()
-    }
-}
diff --git a/compiler/rustc_trait_selection/src/traits/engine.rs b/compiler/rustc_trait_selection/src/traits/engine.rs
index 19dd4ce06b0..61f693e1bd1 100644
--- a/compiler/rustc_trait_selection/src/traits/engine.rs
+++ b/compiler/rustc_trait_selection/src/traits/engine.rs
@@ -1,8 +1,8 @@
 use std::cell::RefCell;
 use std::fmt::Debug;
 
+use super::FulfillmentContext;
 use super::TraitEngine;
-use super::{ChalkFulfillmentContext, FulfillmentContext};
 use crate::solve::FulfillmentCtxt as NextFulfillmentCtxt;
 use crate::traits::error_reporting::TypeErrCtxtExt;
 use crate::traits::NormalizeExt;
@@ -39,7 +39,6 @@ impl<'tcx> TraitEngineExt<'tcx> for dyn TraitEngine<'tcx> {
             (TraitSolver::Next | TraitSolver::NextCoherence, true) => {
                 Box::new(NextFulfillmentCtxt::new(infcx))
             }
-            (TraitSolver::Chalk, false) => Box::new(ChalkFulfillmentContext::new(infcx)),
             _ => bug!(
                 "incompatible combination of -Ztrait-solver flag ({:?}) and InferCtxt::next_trait_solver ({:?})",
                 infcx.tcx.sess.opts.unstable_opts.trait_solver,
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
index f7670d51bdc..5fff645dd22 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
@@ -1059,7 +1059,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 // (which may fail).
                                 span_bug!(span, "WF predicate not satisfied for {:?}", ty);
                             }
-                            TraitSolver::Chalk | TraitSolver::Next | TraitSolver::NextCoherence => {
+                            TraitSolver::Next | TraitSolver::NextCoherence => {
                                 // FIXME: we'll need a better message which takes into account
                                 // which bounds actually failed to hold.
                                 self.tcx.sess.struct_span_err(
@@ -1094,13 +1094,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
 
                     ty::PredicateKind::Ambiguous => span_bug!(span, "ambiguous"),
 
-                    ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                        span_bug!(
-                            span,
-                            "TypeWellFormedFromEnv predicate should only exist in the environment"
-                        )
-                    }
-
                     ty::PredicateKind::AliasRelate(..) => span_bug!(
                         span,
                         "AliasRelate predicate should never be the predicate cause of a SelectionError"
diff --git a/compiler/rustc_trait_selection/src/traits/fulfill.rs b/compiler/rustc_trait_selection/src/traits/fulfill.rs
index e3472a1c4c1..3d96c422256 100644
--- a/compiler/rustc_trait_selection/src/traits/fulfill.rs
+++ b/compiler/rustc_trait_selection/src/traits/fulfill.rs
@@ -359,9 +359,6 @@ impl<'a, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'tcx> {
                     ProcessResult::Changed(mk_pending(vec![obligation.with(infcx.tcx, pred)]))
                 }
                 ty::PredicateKind::Ambiguous => ProcessResult::Unchanged,
-                ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                    bug!("TypeWellFormedFromEnv is only used for Chalk")
-                }
                 ty::PredicateKind::AliasRelate(..) => {
                     bug!("AliasRelate is only used for new solver")
                 }
@@ -627,9 +624,6 @@ impl<'a, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'tcx> {
                     }
                 }
                 ty::PredicateKind::Ambiguous => ProcessResult::Unchanged,
-                ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                    bug!("TypeWellFormedFromEnv is only used for Chalk")
-                }
                 ty::PredicateKind::AliasRelate(..) => {
                     bug!("AliasRelate is only used for new solver")
                 }
diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs
index 720998a51e0..e2ee347b639 100644
--- a/compiler/rustc_trait_selection/src/traits/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/mod.rs
@@ -3,7 +3,6 @@
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/traits/resolution.html
 
 pub mod auto_trait;
-mod chalk_fulfill;
 pub(crate) mod coherence;
 pub mod const_evaluatable;
 mod engine;
@@ -74,8 +73,6 @@ pub use self::util::{
 pub use self::util::{expand_trait_aliases, TraitAliasExpander};
 pub use self::util::{get_vtable_index_of_object_method, impl_item_is_final, upcast_choices};
 
-pub use self::chalk_fulfill::FulfillmentContext as ChalkFulfillmentContext;
-
 pub use rustc_infer::traits::*;
 
 /// Whether to skip the leak check, as part of a future compatibility warning step.
diff --git a/compiler/rustc_trait_selection/src/traits/object_safety.rs b/compiler/rustc_trait_selection/src/traits/object_safety.rs
index 78270b7d535..08be60c65d4 100644
--- a/compiler/rustc_trait_selection/src/traits/object_safety.rs
+++ b/compiler/rustc_trait_selection/src/traits/object_safety.rs
@@ -311,7 +311,7 @@ fn predicate_references_self<'tcx>(
         | ty::ClauseKind::RegionOutlives(..)
         // FIXME(generic_const_exprs): this can mention `Self`
         | ty::ClauseKind::ConstEvaluatable(..)
-        | ty::ClauseKind::TypeWellFormedFromEnv(_) => None,
+         => None,
     }
 }
 
@@ -351,8 +351,7 @@ fn generics_require_sized_self(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
         | ty::ClauseKind::Projection(_)
         | ty::ClauseKind::ConstArgHasType(_, _)
         | ty::ClauseKind::WellFormed(_)
-        | ty::ClauseKind::ConstEvaluatable(_)
-        | ty::ClauseKind::TypeWellFormedFromEnv(_) => false,
+        | ty::ClauseKind::ConstEvaluatable(_) => false,
     })
 }
 
diff --git a/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs
index 83d536c9ca5..42c2c37eca2 100644
--- a/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs
@@ -134,7 +134,7 @@ pub fn compute_implied_outlives_bounds_inner<'tcx>(
                 | ty::PredicateKind::ConstEquate(..)
                 | ty::PredicateKind::Ambiguous
                 | ty::PredicateKind::AliasRelate(..)
-                | ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {}
+                 => {}
 
                 // We need to search through *all* WellFormed predicates
                 ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(arg)) => {
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index cc6521f3b50..f45d348fa96 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -16,7 +16,6 @@ use rustc_middle::ty::{
     self, Binder, GenericParamDefKind, InternalSubsts, SubstsRef, ToPolyTraitRef, ToPredicate,
     TraitPredicate, TraitRef, Ty, TyCtxt, TypeVisitableExt,
 };
-use rustc_session::config::TraitSolver;
 use rustc_span::def_id::DefId;
 
 use crate::traits::project::{normalize_with_depth, normalize_with_depth_to};
@@ -830,13 +829,10 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
         debug!(?closure_def_id, ?trait_ref, ?nested, "confirm closure candidate obligations");
 
-        // FIXME: Chalk
-        if self.tcx().sess.opts.unstable_opts.trait_solver != TraitSolver::Chalk {
-            nested.push(obligation.with(
-                self.tcx(),
-                ty::Binder::dummy(ty::PredicateKind::ClosureKind(closure_def_id, substs, kind)),
-            ));
-        }
+        nested.push(obligation.with(
+            self.tcx(),
+            ty::Binder::dummy(ty::PredicateKind::ClosureKind(closure_def_id, substs, kind)),
+        ));
 
         Ok(nested)
     }
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index c12d92b9012..eb11163de42 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -972,9 +972,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                         }
                     }
                 }
-                ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                    bug!("TypeWellFormedFromEnv is only used for chalk")
-                }
                 ty::PredicateKind::AliasRelate(..) => {
                     bug!("AliasRelate is only used for new solver")
                 }
diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs
index 8bb4288f80d..86c7fc45ff7 100644
--- a/compiler/rustc_trait_selection/src/traits/wf.rs
+++ b/compiler/rustc_trait_selection/src/traits/wf.rs
@@ -184,8 +184,7 @@ pub fn predicate_obligations<'tcx>(
         | ty::PredicateKind::Coerce(..)
         | ty::PredicateKind::ConstEquate(..)
         | ty::PredicateKind::Ambiguous
-        | ty::PredicateKind::AliasRelate(..)
-        | ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
+        | ty::PredicateKind::AliasRelate(..) => {
             bug!("We should only wf check where clauses, unexpected predicate: {predicate:?}")
         }
     }
@@ -1005,8 +1004,7 @@ pub(crate) fn required_region_bounds<'tcx>(
                 | ty::ClauseKind::Projection(_)
                 | ty::ClauseKind::ConstArgHasType(_, _)
                 | ty::ClauseKind::WellFormed(_)
-                | ty::ClauseKind::ConstEvaluatable(_)
-                | ty::ClauseKind::TypeWellFormedFromEnv(_) => None,
+                | ty::ClauseKind::ConstEvaluatable(_) => None,
             }
         })
         .collect()
diff --git a/compiler/rustc_traits/Cargo.toml b/compiler/rustc_traits/Cargo.toml
index 189f72d478e..37e00c0e4bc 100644
--- a/compiler/rustc_traits/Cargo.toml
+++ b/compiler/rustc_traits/Cargo.toml
@@ -11,9 +11,6 @@ rustc_hir = { path = "../rustc_hir" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
-chalk-ir = "0.92.0"
-chalk-engine = "0.92.0"
-chalk-solve = "0.92.0"
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
 rustc_infer = { path = "../rustc_infer" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
diff --git a/compiler/rustc_traits/src/chalk/db.rs b/compiler/rustc_traits/src/chalk/db.rs
deleted file mode 100644
index 0435cd63e80..00000000000
--- a/compiler/rustc_traits/src/chalk/db.rs
+++ /dev/null
@@ -1,796 +0,0 @@
-//! Provides the `RustIrDatabase` implementation for `chalk-solve`
-//!
-//! The purpose of the `chalk_solve::RustIrDatabase` is to get data about
-//! specific types, such as bounds, where clauses, or fields. This file contains
-//! the minimal logic to assemble the types for `chalk-solve` by calling out to
-//! either the `TyCtxt` (for information about types) or
-//! `crate::chalk::lowering` (to lower rustc types into Chalk types).
-
-use rustc_middle::traits::ChalkRustInterner as RustInterner;
-use rustc_middle::ty::{self, AssocKind, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable};
-use rustc_middle::ty::{InternalSubsts, SubstsRef};
-use rustc_target::abi::{Integer, IntegerType};
-
-use rustc_ast::ast;
-
-use rustc_hir::def_id::DefId;
-
-use rustc_span::symbol::sym;
-
-use std::fmt;
-use std::sync::Arc;
-
-use crate::chalk::lowering::LowerInto;
-
-pub struct RustIrDatabase<'tcx> {
-    pub(crate) interner: RustInterner<'tcx>,
-}
-
-impl fmt::Debug for RustIrDatabase<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "RustIrDatabase")
-    }
-}
-
-impl<'tcx> RustIrDatabase<'tcx> {
-    fn where_clauses_for(
-        &self,
-        def_id: DefId,
-        bound_vars: SubstsRef<'tcx>,
-    ) -> Vec<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>> {
-        self.interner
-            .tcx
-            .predicates_defined_on(def_id)
-            .instantiate_own(self.interner.tcx, bound_vars)
-            .filter_map(|(wc, _)| LowerInto::lower_into(wc.as_predicate(), self.interner))
-            .collect()
-    }
-
-    fn bounds_for<T>(&self, def_id: DefId, bound_vars: SubstsRef<'tcx>) -> Vec<T>
-    where
-        ty::Predicate<'tcx>: LowerInto<'tcx, std::option::Option<T>>,
-    {
-        self.interner
-            .tcx
-            .explicit_item_bounds(def_id)
-            .subst_iter_copied(self.interner.tcx, &bound_vars)
-            .filter_map(|(bound, _)| {
-                LowerInto::<Option<_>>::lower_into(bound.as_predicate(), self.interner)
-            })
-            .collect()
-    }
-}
-
-impl<'tcx> chalk_solve::RustIrDatabase<RustInterner<'tcx>> for RustIrDatabase<'tcx> {
-    fn interner(&self) -> RustInterner<'tcx> {
-        self.interner
-    }
-
-    fn associated_ty_data(
-        &self,
-        assoc_type_id: chalk_ir::AssocTypeId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::AssociatedTyDatum<RustInterner<'tcx>>> {
-        let def_id = assoc_type_id.0;
-        let assoc_item = self.interner.tcx.associated_item(def_id);
-        let Some(trait_def_id) = assoc_item.trait_container(self.interner.tcx) else {
-            unimplemented!("Not possible??");
-        };
-        match assoc_item.kind {
-            AssocKind::Type => {}
-            _ => unimplemented!("Not possible??"),
-        }
-        let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
-        let binders = binders_for(self.interner, bound_vars);
-
-        let where_clauses = self.where_clauses_for(def_id, bound_vars);
-        let bounds = self.bounds_for(def_id, bound_vars);
-
-        Arc::new(chalk_solve::rust_ir::AssociatedTyDatum {
-            trait_id: chalk_ir::TraitId(trait_def_id),
-            id: assoc_type_id,
-            name: (),
-            binders: chalk_ir::Binders::new(
-                binders,
-                chalk_solve::rust_ir::AssociatedTyDatumBound { bounds, where_clauses },
-            ),
-        })
-    }
-
-    fn trait_datum(
-        &self,
-        trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::TraitDatum<RustInterner<'tcx>>> {
-        use chalk_solve::rust_ir::WellKnownTrait::*;
-
-        let def_id = trait_id.0;
-        let trait_def = self.interner.tcx.trait_def(def_id);
-
-        let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
-        let binders = binders_for(self.interner, bound_vars);
-
-        let where_clauses = self.where_clauses_for(def_id, bound_vars);
-
-        let associated_ty_ids: Vec<_> = self
-            .interner
-            .tcx
-            .associated_items(def_id)
-            .in_definition_order()
-            .filter(|i| i.kind == AssocKind::Type)
-            .map(|i| chalk_ir::AssocTypeId(i.def_id))
-            .collect();
-
-        let lang_items = self.interner.tcx.lang_items();
-        let well_known = if lang_items.sized_trait() == Some(def_id) {
-            Some(Sized)
-        } else if lang_items.copy_trait() == Some(def_id) {
-            Some(Copy)
-        } else if lang_items.clone_trait() == Some(def_id) {
-            Some(Clone)
-        } else if lang_items.drop_trait() == Some(def_id) {
-            Some(Drop)
-        } else if lang_items.fn_trait() == Some(def_id) {
-            Some(Fn)
-        } else if lang_items.fn_once_trait() == Some(def_id) {
-            Some(FnOnce)
-        } else if lang_items.fn_mut_trait() == Some(def_id) {
-            Some(FnMut)
-        } else if lang_items.unsize_trait() == Some(def_id) {
-            Some(Unsize)
-        } else if lang_items.unpin_trait() == Some(def_id) {
-            Some(Unpin)
-        } else if lang_items.coerce_unsized_trait() == Some(def_id) {
-            Some(CoerceUnsized)
-        } else if lang_items.dispatch_from_dyn_trait() == Some(def_id) {
-            Some(DispatchFromDyn)
-        } else if lang_items.tuple_trait() == Some(def_id) {
-            Some(Tuple)
-        } else {
-            None
-        };
-        Arc::new(chalk_solve::rust_ir::TraitDatum {
-            id: trait_id,
-            binders: chalk_ir::Binders::new(
-                binders,
-                chalk_solve::rust_ir::TraitDatumBound { where_clauses },
-            ),
-            flags: chalk_solve::rust_ir::TraitFlags {
-                auto: trait_def.has_auto_impl,
-                marker: trait_def.is_marker,
-                upstream: !def_id.is_local(),
-                fundamental: self.interner.tcx.has_attr(def_id, sym::fundamental),
-                non_enumerable: true,
-                coinductive: false,
-            },
-            associated_ty_ids,
-            well_known,
-        })
-    }
-
-    fn adt_datum(
-        &self,
-        adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::AdtDatum<RustInterner<'tcx>>> {
-        let adt_def = adt_id.0;
-
-        let bound_vars = bound_vars_for_item(self.interner.tcx, adt_def.did());
-        let binders = binders_for(self.interner, bound_vars);
-
-        let where_clauses = self.where_clauses_for(adt_def.did(), bound_vars);
-
-        let variants: Vec<_> = adt_def
-            .variants()
-            .iter()
-            .map(|variant| chalk_solve::rust_ir::AdtVariantDatum {
-                fields: variant
-                    .fields
-                    .iter()
-                    .map(|field| field.ty(self.interner.tcx, bound_vars).lower_into(self.interner))
-                    .collect(),
-            })
-            .collect();
-        Arc::new(chalk_solve::rust_ir::AdtDatum {
-            id: adt_id,
-            binders: chalk_ir::Binders::new(
-                binders,
-                chalk_solve::rust_ir::AdtDatumBound { variants, where_clauses },
-            ),
-            flags: chalk_solve::rust_ir::AdtFlags {
-                upstream: !adt_def.did().is_local(),
-                fundamental: adt_def.is_fundamental(),
-                phantom_data: adt_def.is_phantom_data(),
-            },
-            kind: match adt_def.adt_kind() {
-                ty::AdtKind::Struct => chalk_solve::rust_ir::AdtKind::Struct,
-                ty::AdtKind::Union => chalk_solve::rust_ir::AdtKind::Union,
-                ty::AdtKind::Enum => chalk_solve::rust_ir::AdtKind::Enum,
-            },
-        })
-    }
-
-    fn adt_repr(
-        &self,
-        adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::AdtRepr<RustInterner<'tcx>>> {
-        let adt_def = adt_id.0;
-        let int = |i| chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Int(i)).intern(self.interner);
-        let uint = |i| chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Uint(i)).intern(self.interner);
-        Arc::new(chalk_solve::rust_ir::AdtRepr {
-            c: adt_def.repr().c(),
-            packed: adt_def.repr().packed(),
-            int: adt_def.repr().int.map(|i| match i {
-                IntegerType::Pointer(true) => int(chalk_ir::IntTy::Isize),
-                IntegerType::Pointer(false) => uint(chalk_ir::UintTy::Usize),
-                IntegerType::Fixed(i, true) => match i {
-                    Integer::I8 => int(chalk_ir::IntTy::I8),
-                    Integer::I16 => int(chalk_ir::IntTy::I16),
-                    Integer::I32 => int(chalk_ir::IntTy::I32),
-                    Integer::I64 => int(chalk_ir::IntTy::I64),
-                    Integer::I128 => int(chalk_ir::IntTy::I128),
-                },
-                IntegerType::Fixed(i, false) => match i {
-                    Integer::I8 => uint(chalk_ir::UintTy::U8),
-                    Integer::I16 => uint(chalk_ir::UintTy::U16),
-                    Integer::I32 => uint(chalk_ir::UintTy::U32),
-                    Integer::I64 => uint(chalk_ir::UintTy::U64),
-                    Integer::I128 => uint(chalk_ir::UintTy::U128),
-                },
-            }),
-        })
-    }
-
-    fn adt_size_align(
-        &self,
-        adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::AdtSizeAlign> {
-        let tcx = self.interner.tcx;
-        let did = adt_id.0.did();
-
-        // Grab the ADT and the param we might need to calculate its layout
-        let param_env = tcx.param_env(did);
-        let adt_ty = tcx.type_of(did).subst_identity();
-
-        // The ADT is a 1-zst if it's a ZST and its alignment is 1.
-        // Mark the ADT as _not_ a 1-zst if there was a layout error.
-        let one_zst = if let Ok(layout) = tcx.layout_of(param_env.and(adt_ty)) {
-            layout.is_zst() && layout.align.abi.bytes() == 1
-        } else {
-            false
-        };
-
-        Arc::new(chalk_solve::rust_ir::AdtSizeAlign::from_one_zst(one_zst))
-    }
-
-    fn fn_def_datum(
-        &self,
-        fn_def_id: chalk_ir::FnDefId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::FnDefDatum<RustInterner<'tcx>>> {
-        let def_id = fn_def_id.0;
-        let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
-        let binders = binders_for(self.interner, bound_vars);
-
-        let where_clauses = self.where_clauses_for(def_id, bound_vars);
-
-        let sig = self.interner.tcx.fn_sig(def_id);
-        let (inputs_and_output, iobinders, _) = crate::chalk::lowering::collect_bound_vars(
-            self.interner,
-            self.interner.tcx,
-            sig.map_bound(|s| s.inputs_and_output()).subst(self.interner.tcx, bound_vars),
-        );
-
-        let argument_types = inputs_and_output[..inputs_and_output.len() - 1]
-            .iter()
-            .map(|t| sig.rebind(*t).subst(self.interner.tcx, &bound_vars).lower_into(self.interner))
-            .collect();
-
-        let return_type = sig
-            .rebind(inputs_and_output[inputs_and_output.len() - 1])
-            .subst(self.interner.tcx, &bound_vars)
-            .lower_into(self.interner);
-
-        let bound = chalk_solve::rust_ir::FnDefDatumBound {
-            inputs_and_output: chalk_ir::Binders::new(
-                iobinders,
-                chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
-            ),
-            where_clauses,
-        };
-        Arc::new(chalk_solve::rust_ir::FnDefDatum {
-            id: fn_def_id,
-            sig: sig.skip_binder().lower_into(self.interner),
-            binders: chalk_ir::Binders::new(binders, bound),
-        })
-    }
-
-    fn impl_datum(
-        &self,
-        impl_id: chalk_ir::ImplId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::ImplDatum<RustInterner<'tcx>>> {
-        let def_id = impl_id.0;
-        let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
-        let binders = binders_for(self.interner, bound_vars);
-
-        let trait_ref = self.interner.tcx.impl_trait_ref(def_id).expect("not an impl");
-        let trait_ref = trait_ref.subst(self.interner.tcx, bound_vars);
-
-        let where_clauses = self.where_clauses_for(def_id, bound_vars);
-
-        let value = chalk_solve::rust_ir::ImplDatumBound {
-            trait_ref: trait_ref.lower_into(self.interner),
-            where_clauses,
-        };
-
-        let associated_ty_value_ids: Vec<_> = self
-            .interner
-            .tcx
-            .associated_items(def_id)
-            .in_definition_order()
-            .filter(|i| i.kind == AssocKind::Type)
-            .map(|i| chalk_solve::rust_ir::AssociatedTyValueId(i.def_id))
-            .collect();
-
-        Arc::new(chalk_solve::rust_ir::ImplDatum {
-            polarity: self.interner.tcx.impl_polarity(def_id).lower_into(self.interner),
-            binders: chalk_ir::Binders::new(binders, value),
-            impl_type: chalk_solve::rust_ir::ImplType::Local,
-            associated_ty_value_ids,
-        })
-    }
-
-    fn impls_for_trait(
-        &self,
-        trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
-        parameters: &[chalk_ir::GenericArg<RustInterner<'tcx>>],
-        _binders: &chalk_ir::CanonicalVarKinds<RustInterner<'tcx>>,
-    ) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
-        let def_id = trait_id.0;
-
-        // FIXME(chalk): use TraitDef::for_each_relevant_impl, but that will
-        // require us to be able to interconvert `Ty<'tcx>`, and we're
-        // not there yet.
-
-        let all_impls = self.interner.tcx.all_impls(def_id);
-        let matched_impls = all_impls.filter(|impl_def_id| {
-            use chalk_ir::could_match::CouldMatch;
-            let trait_ref = self.interner.tcx.impl_trait_ref(*impl_def_id).unwrap();
-            let bound_vars = bound_vars_for_item(self.interner.tcx, *impl_def_id);
-
-            let self_ty = trait_ref.map_bound(|t| t.self_ty());
-            let self_ty = self_ty.subst(self.interner.tcx, bound_vars);
-            let lowered_ty = self_ty.lower_into(self.interner);
-
-            parameters[0].assert_ty_ref(self.interner).could_match(
-                self.interner,
-                self.unification_database(),
-                &lowered_ty,
-            )
-        });
-
-        let impls = matched_impls.map(chalk_ir::ImplId).collect();
-        impls
-    }
-
-    fn impl_provided_for(
-        &self,
-        auto_trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
-        chalk_ty: &chalk_ir::TyKind<RustInterner<'tcx>>,
-    ) -> bool {
-        use chalk_ir::Scalar::*;
-        use chalk_ir::TyKind::*;
-
-        let trait_def_id = auto_trait_id.0;
-        let all_impls = self.interner.tcx.all_impls(trait_def_id);
-        for impl_def_id in all_impls {
-            let trait_ref = self.interner.tcx.impl_trait_ref(impl_def_id).unwrap().subst_identity();
-            let self_ty = trait_ref.self_ty();
-            let provides = match (self_ty.kind(), chalk_ty) {
-                (&ty::Adt(impl_adt_def, ..), Adt(id, ..)) => impl_adt_def.did() == id.0.did(),
-                (_, AssociatedType(_ty_id, ..)) => {
-                    // FIXME(chalk): See https://github.com/rust-lang/rust/pull/77152#discussion_r494484774
-                    false
-                }
-                (ty::Bool, Scalar(Bool)) => true,
-                (ty::Char, Scalar(Char)) => true,
-                (ty::Int(ty1), Scalar(Int(ty2))) => matches!(
-                    (ty1, ty2),
-                    (ty::IntTy::Isize, chalk_ir::IntTy::Isize)
-                        | (ty::IntTy::I8, chalk_ir::IntTy::I8)
-                        | (ty::IntTy::I16, chalk_ir::IntTy::I16)
-                        | (ty::IntTy::I32, chalk_ir::IntTy::I32)
-                        | (ty::IntTy::I64, chalk_ir::IntTy::I64)
-                        | (ty::IntTy::I128, chalk_ir::IntTy::I128)
-                ),
-                (ty::Uint(ty1), Scalar(Uint(ty2))) => matches!(
-                    (ty1, ty2),
-                    (ty::UintTy::Usize, chalk_ir::UintTy::Usize)
-                        | (ty::UintTy::U8, chalk_ir::UintTy::U8)
-                        | (ty::UintTy::U16, chalk_ir::UintTy::U16)
-                        | (ty::UintTy::U32, chalk_ir::UintTy::U32)
-                        | (ty::UintTy::U64, chalk_ir::UintTy::U64)
-                        | (ty::UintTy::U128, chalk_ir::UintTy::U128)
-                ),
-                (ty::Float(ty1), Scalar(Float(ty2))) => matches!(
-                    (ty1, ty2),
-                    (ty::FloatTy::F32, chalk_ir::FloatTy::F32)
-                        | (ty::FloatTy::F64, chalk_ir::FloatTy::F64)
-                ),
-                (&ty::Tuple(substs), Tuple(len, _)) => substs.len() == *len,
-                (&ty::Array(..), Array(..)) => true,
-                (&ty::Slice(..), Slice(..)) => true,
-                (&ty::RawPtr(type_and_mut), Raw(mutability, _)) => {
-                    match (type_and_mut.mutbl, mutability) {
-                        (ast::Mutability::Mut, chalk_ir::Mutability::Mut) => true,
-                        (ast::Mutability::Mut, chalk_ir::Mutability::Not) => false,
-                        (ast::Mutability::Not, chalk_ir::Mutability::Mut) => false,
-                        (ast::Mutability::Not, chalk_ir::Mutability::Not) => true,
-                    }
-                }
-                (&ty::Ref(.., mutability1), Ref(mutability2, ..)) => {
-                    match (mutability1, mutability2) {
-                        (ast::Mutability::Mut, chalk_ir::Mutability::Mut) => true,
-                        (ast::Mutability::Mut, chalk_ir::Mutability::Not) => false,
-                        (ast::Mutability::Not, chalk_ir::Mutability::Mut) => false,
-                        (ast::Mutability::Not, chalk_ir::Mutability::Not) => true,
-                    }
-                }
-                (
-                    &ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }),
-                    OpaqueType(opaque_ty_id, ..),
-                ) => def_id == opaque_ty_id.0,
-                (&ty::FnDef(def_id, ..), FnDef(fn_def_id, ..)) => def_id == fn_def_id.0,
-                (&ty::Str, Str) => true,
-                (&ty::Never, Never) => true,
-                (&ty::Closure(def_id, ..), Closure(closure_id, _)) => def_id == closure_id.0,
-                (&ty::Foreign(def_id), Foreign(foreign_def_id)) => def_id == foreign_def_id.0,
-                (&ty::Error(..), Error) => false,
-                _ => false,
-            };
-            if provides {
-                return true;
-            }
-        }
-        false
-    }
-
-    fn associated_ty_value(
-        &self,
-        associated_ty_id: chalk_solve::rust_ir::AssociatedTyValueId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::AssociatedTyValue<RustInterner<'tcx>>> {
-        let def_id = associated_ty_id.0;
-        let assoc_item = self.interner.tcx.associated_item(def_id);
-        let impl_id = assoc_item.container_id(self.interner.tcx);
-        match assoc_item.kind {
-            AssocKind::Type => {}
-            _ => unimplemented!("Not possible??"),
-        }
-
-        let trait_item_id = assoc_item.trait_item_def_id.expect("assoc_ty with no trait version");
-        let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
-        let binders = binders_for(self.interner, bound_vars);
-        let ty = self
-            .interner
-            .tcx
-            .type_of(def_id)
-            .subst(self.interner.tcx, bound_vars)
-            .lower_into(self.interner);
-
-        Arc::new(chalk_solve::rust_ir::AssociatedTyValue {
-            impl_id: chalk_ir::ImplId(impl_id),
-            associated_ty_id: chalk_ir::AssocTypeId(trait_item_id),
-            value: chalk_ir::Binders::new(
-                binders,
-                chalk_solve::rust_ir::AssociatedTyValueBound { ty },
-            ),
-        })
-    }
-
-    fn custom_clauses(&self) -> Vec<chalk_ir::ProgramClause<RustInterner<'tcx>>> {
-        vec![]
-    }
-
-    fn local_impls_to_coherence_check(
-        &self,
-        _trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
-    ) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
-        unimplemented!()
-    }
-
-    fn opaque_ty_data(
-        &self,
-        opaque_ty_id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::OpaqueTyDatum<RustInterner<'tcx>>> {
-        let bound_vars = ty::fold::shift_vars(
-            self.interner.tcx,
-            bound_vars_for_item(self.interner.tcx, opaque_ty_id.0),
-            1,
-        );
-        let where_clauses = self.where_clauses_for(opaque_ty_id.0, bound_vars);
-
-        let identity_substs = InternalSubsts::identity_for_item(self.interner.tcx, opaque_ty_id.0);
-
-        let explicit_item_bounds = self.interner.tcx.explicit_item_bounds(opaque_ty_id.0);
-        let bounds =
-            explicit_item_bounds
-                .subst_iter_copied(self.interner.tcx, &bound_vars)
-                .map(|(bound, _)| {
-                    bound.fold_with(&mut ReplaceOpaqueTyFolder {
-                        tcx: self.interner.tcx,
-                        opaque_ty_id,
-                        identity_substs,
-                        binder_index: ty::INNERMOST,
-                    })
-                })
-                .filter_map(|bound| {
-                    LowerInto::<
-                    Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>
-                >::lower_into(bound.as_predicate(), self.interner)
-                })
-                .collect();
-
-        // Binder for the bound variable representing the concrete impl Trait type.
-        let existential_binder = chalk_ir::VariableKinds::from1(
-            self.interner,
-            chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General),
-        );
-
-        let value = chalk_solve::rust_ir::OpaqueTyDatumBound {
-            bounds: chalk_ir::Binders::new(existential_binder.clone(), bounds),
-            where_clauses: chalk_ir::Binders::new(existential_binder, where_clauses),
-        };
-
-        let binders = binders_for(self.interner, bound_vars);
-        Arc::new(chalk_solve::rust_ir::OpaqueTyDatum {
-            opaque_ty_id,
-            bound: chalk_ir::Binders::new(binders, value),
-        })
-    }
-
-    fn program_clauses_for_env(
-        &self,
-        environment: &chalk_ir::Environment<RustInterner<'tcx>>,
-    ) -> chalk_ir::ProgramClauses<RustInterner<'tcx>> {
-        chalk_solve::program_clauses_for_env(self, environment)
-    }
-
-    fn well_known_trait_id(
-        &self,
-        well_known_trait: chalk_solve::rust_ir::WellKnownTrait,
-    ) -> Option<chalk_ir::TraitId<RustInterner<'tcx>>> {
-        use chalk_solve::rust_ir::WellKnownTrait::*;
-        let lang_items = self.interner.tcx.lang_items();
-        let def_id = match well_known_trait {
-            Sized => lang_items.sized_trait(),
-            Copy => lang_items.copy_trait(),
-            Clone => lang_items.clone_trait(),
-            Drop => lang_items.drop_trait(),
-            Fn => lang_items.fn_trait(),
-            FnMut => lang_items.fn_mut_trait(),
-            FnOnce => lang_items.fn_once_trait(),
-            Generator => lang_items.gen_trait(),
-            Unsize => lang_items.unsize_trait(),
-            Unpin => lang_items.unpin_trait(),
-            CoerceUnsized => lang_items.coerce_unsized_trait(),
-            DiscriminantKind => lang_items.discriminant_kind_trait(),
-            DispatchFromDyn => lang_items.dispatch_from_dyn_trait(),
-            Tuple => lang_items.tuple_trait(),
-            Pointee => lang_items.pointee_trait(),
-            FnPtr => lang_items.fn_ptr_trait(),
-        };
-        def_id.map(chalk_ir::TraitId)
-    }
-
-    fn is_object_safe(&self, trait_id: chalk_ir::TraitId<RustInterner<'tcx>>) -> bool {
-        self.interner.tcx.check_is_object_safe(trait_id.0)
-    }
-
-    fn hidden_opaque_type(
-        &self,
-        _id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
-    ) -> chalk_ir::Ty<RustInterner<'tcx>> {
-        // FIXME(chalk): actually get hidden ty
-        self.interner.tcx.types.unit.lower_into(self.interner)
-    }
-
-    fn closure_kind(
-        &self,
-        _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
-        substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
-    ) -> chalk_solve::rust_ir::ClosureKind {
-        let kind = &substs.as_slice(self.interner)[substs.len(self.interner) - 3];
-        match kind.assert_ty_ref(self.interner).kind(self.interner) {
-            chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Int(int_ty)) => match int_ty {
-                chalk_ir::IntTy::I8 => chalk_solve::rust_ir::ClosureKind::Fn,
-                chalk_ir::IntTy::I16 => chalk_solve::rust_ir::ClosureKind::FnMut,
-                chalk_ir::IntTy::I32 => chalk_solve::rust_ir::ClosureKind::FnOnce,
-                _ => bug!("bad closure kind"),
-            },
-            _ => bug!("bad closure kind"),
-        }
-    }
-
-    fn closure_inputs_and_output(
-        &self,
-        _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
-        substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
-    ) -> chalk_ir::Binders<chalk_solve::rust_ir::FnDefInputsAndOutputDatum<RustInterner<'tcx>>>
-    {
-        let sig = &substs.as_slice(self.interner)[substs.len(self.interner) - 2];
-        match sig.assert_ty_ref(self.interner).kind(self.interner) {
-            chalk_ir::TyKind::Function(f) => {
-                let substitution = f.substitution.0.as_slice(self.interner);
-                let return_type = substitution.last().unwrap().assert_ty_ref(self.interner).clone();
-                // Closure arguments are tupled
-                let argument_tuple = substitution[0].assert_ty_ref(self.interner);
-                let argument_types = match argument_tuple.kind(self.interner) {
-                    chalk_ir::TyKind::Tuple(_len, substitution) => substitution
-                        .iter(self.interner)
-                        .map(|arg| arg.assert_ty_ref(self.interner))
-                        .cloned()
-                        .collect(),
-                    _ => bug!("Expecting closure FnSig args to be tupled."),
-                };
-
-                chalk_ir::Binders::new(
-                    chalk_ir::VariableKinds::from_iter(
-                        self.interner,
-                        (0..f.num_binders).map(|_| chalk_ir::VariableKind::Lifetime),
-                    ),
-                    chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
-                )
-            }
-            _ => panic!("Invalid sig."),
-        }
-    }
-
-    fn closure_upvars(
-        &self,
-        _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
-        substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
-    ) -> chalk_ir::Binders<chalk_ir::Ty<RustInterner<'tcx>>> {
-        let inputs_and_output = self.closure_inputs_and_output(_closure_id, substs);
-        let tuple = substs.as_slice(self.interner).last().unwrap().assert_ty_ref(self.interner);
-        inputs_and_output.map_ref(|_| tuple.clone())
-    }
-
-    fn closure_fn_substitution(
-        &self,
-        _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
-        substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
-    ) -> chalk_ir::Substitution<RustInterner<'tcx>> {
-        let substitution = &substs.as_slice(self.interner)[0..substs.len(self.interner) - 3];
-        chalk_ir::Substitution::from_iter(self.interner, substitution)
-    }
-
-    fn generator_datum(
-        &self,
-        _generator_id: chalk_ir::GeneratorId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::GeneratorDatum<RustInterner<'tcx>>> {
-        unimplemented!()
-    }
-
-    fn generator_witness_datum(
-        &self,
-        _generator_id: chalk_ir::GeneratorId<RustInterner<'tcx>>,
-    ) -> Arc<chalk_solve::rust_ir::GeneratorWitnessDatum<RustInterner<'tcx>>> {
-        unimplemented!()
-    }
-
-    fn unification_database(&self) -> &dyn chalk_ir::UnificationDatabase<RustInterner<'tcx>> {
-        self
-    }
-
-    fn discriminant_type(
-        &self,
-        _: chalk_ir::Ty<RustInterner<'tcx>>,
-    ) -> chalk_ir::Ty<RustInterner<'tcx>> {
-        unimplemented!()
-    }
-}
-
-impl<'tcx> chalk_ir::UnificationDatabase<RustInterner<'tcx>> for RustIrDatabase<'tcx> {
-    fn fn_def_variance(
-        &self,
-        def_id: chalk_ir::FnDefId<RustInterner<'tcx>>,
-    ) -> chalk_ir::Variances<RustInterner<'tcx>> {
-        let variances = self.interner.tcx.variances_of(def_id.0);
-        chalk_ir::Variances::from_iter(
-            self.interner,
-            variances.iter().map(|v| v.lower_into(self.interner)),
-        )
-    }
-
-    fn adt_variance(
-        &self,
-        adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
-    ) -> chalk_ir::Variances<RustInterner<'tcx>> {
-        let variances = self.interner.tcx.variances_of(adt_id.0.did());
-        chalk_ir::Variances::from_iter(
-            self.interner,
-            variances.iter().map(|v| v.lower_into(self.interner)),
-        )
-    }
-}
-
-/// Creates an `InternalSubsts` that maps each generic parameter to a higher-ranked
-/// var bound at index `0`. For types, we use a `BoundVar` index equal to
-/// the type parameter index. For regions, we use the `BoundRegionKind::BrNamed`
-/// variant (which has a `DefId`).
-fn bound_vars_for_item(tcx: TyCtxt<'_>, def_id: DefId) -> SubstsRef<'_> {
-    InternalSubsts::for_item(tcx, def_id, |param, substs| match param.kind {
-        ty::GenericParamDefKind::Type { .. } => tcx
-            .mk_bound(
-                ty::INNERMOST,
-                ty::BoundTy {
-                    var: ty::BoundVar::from(param.index),
-                    kind: ty::BoundTyKind::Param(param.def_id, param.name),
-                },
-            )
-            .into(),
-
-        ty::GenericParamDefKind::Lifetime => {
-            let br = ty::BoundRegion {
-                var: ty::BoundVar::from_usize(substs.len()),
-                kind: ty::BrAnon(None),
-            };
-            ty::Region::new_late_bound(tcx, ty::INNERMOST, br).into()
-        }
-
-        ty::GenericParamDefKind::Const { .. } => tcx
-            .mk_const(
-                ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from(param.index)),
-                tcx.type_of(param.def_id).subst_identity(),
-            )
-            .into(),
-    })
-}
-
-fn binders_for<'tcx>(
-    interner: RustInterner<'tcx>,
-    bound_vars: SubstsRef<'tcx>,
-) -> chalk_ir::VariableKinds<RustInterner<'tcx>> {
-    chalk_ir::VariableKinds::from_iter(
-        interner,
-        bound_vars.iter().map(|arg| match arg.unpack() {
-            ty::subst::GenericArgKind::Lifetime(_re) => chalk_ir::VariableKind::Lifetime,
-            ty::subst::GenericArgKind::Type(_ty) => {
-                chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General)
-            }
-            ty::subst::GenericArgKind::Const(c) => {
-                chalk_ir::VariableKind::Const(c.ty().lower_into(interner))
-            }
-        }),
-    )
-}
-
-struct ReplaceOpaqueTyFolder<'tcx> {
-    tcx: TyCtxt<'tcx>,
-    opaque_ty_id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
-    identity_substs: SubstsRef<'tcx>,
-    binder_index: ty::DebruijnIndex,
-}
-
-impl<'tcx> ty::TypeFolder<TyCtxt<'tcx>> for ReplaceOpaqueTyFolder<'tcx> {
-    fn interner(&self) -> TyCtxt<'tcx> {
-        self.tcx
-    }
-
-    fn fold_binder<T: TypeFoldable<TyCtxt<'tcx>>>(
-        &mut self,
-        t: ty::Binder<'tcx, T>,
-    ) -> ty::Binder<'tcx, T> {
-        self.binder_index.shift_in(1);
-        let t = t.super_fold_with(self);
-        self.binder_index.shift_out(1);
-        t
-    }
-
-    fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-        if let ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs, .. }) = *ty.kind() {
-            if def_id == self.opaque_ty_id.0 && substs == self.identity_substs {
-                return self
-                    .tcx
-                    .mk_bound(self.binder_index, ty::BoundTy::from(ty::BoundVar::from_u32(0)));
-            }
-        }
-        ty
-    }
-}
diff --git a/compiler/rustc_traits/src/chalk/lowering.rs b/compiler/rustc_traits/src/chalk/lowering.rs
deleted file mode 100644
index b7db56d3db8..00000000000
--- a/compiler/rustc_traits/src/chalk/lowering.rs
+++ /dev/null
@@ -1,1234 +0,0 @@
-//! Contains the logic to lower rustc types into Chalk types
-//!
-//! In many cases there is a 1:1 relationship between a rustc type and a Chalk type.
-//! For example, a `SubstsRef` maps almost directly to a `Substitution`. In some
-//! other cases, such as `Param`s, there is no Chalk type, so we have to handle
-//! accordingly.
-//!
-//! ## `Ty` lowering
-//! Much of the `Ty` lowering is 1:1 with Chalk. (Or will be eventually). A
-//! helpful table for what types lower to what can be found in the
-//! [Chalk book](https://rust-lang.github.io/chalk/book/types/rust_types.html).
-//! The most notable difference lies with `Param`s. To convert from rustc to
-//! Chalk, we eagerly and deeply convert `Param`s to placeholders (in goals) or
-//! bound variables (for clause generation through functions in `db`).
-//!
-//! ## `Region` lowering
-//! Regions are handled in rustc and Chalk is quite differently. In rustc, there
-//! is a difference between "early bound" and "late bound" regions, where only
-//! the late bound regions have a `DebruijnIndex`. Moreover, in Chalk all
-//! regions (Lifetimes) have an associated index. In rustc, only `BrAnon`s have
-//! an index, whereas `BrNamed` don't. In order to lower regions to Chalk, we
-//! convert all regions into `BrAnon` late-bound regions.
-//!
-//! ## `Const` lowering
-//! Chalk doesn't handle consts currently, so consts are currently lowered to
-//! an empty tuple.
-//!
-//! ## Bound variable collection
-//! Another difference between rustc and Chalk lies in the handling of binders.
-//! Chalk requires that we store the bound parameter kinds, whereas rustc does
-//! not. To lower anything wrapped in a `Binder`, we first deeply find any bound
-//! variables from the current `Binder`.
-
-use rustc_ast::ast;
-use rustc_middle::traits::{ChalkEnvironmentAndGoal, ChalkRustInterner as RustInterner};
-use rustc_middle::ty::subst::{GenericArg, GenericArgKind, SubstsRef};
-use rustc_middle::ty::{
-    self, Binder, Region, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable,
-    TypeSuperVisitable, TypeVisitable, TypeVisitor,
-};
-use rustc_span::def_id::DefId;
-
-use chalk_ir::{FnSig, ForeignDefId};
-use rustc_hir::Unsafety;
-use std::collections::btree_map::{BTreeMap, Entry};
-use std::ops::ControlFlow;
-
-/// Essentially an `Into` with a `&RustInterner` parameter
-pub(crate) trait LowerInto<'tcx, T> {
-    /// Lower a rustc construct (e.g., `ty::TraitPredicate`) to a chalk type, consuming `self`.
-    fn lower_into(self, interner: RustInterner<'tcx>) -> T;
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::Substitution<RustInterner<'tcx>>> for SubstsRef<'tcx> {
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> chalk_ir::Substitution<RustInterner<'tcx>> {
-        chalk_ir::Substitution::from_iter(interner, self.iter().map(|s| s.lower_into(interner)))
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::Substitution<RustInterner<'tcx>>>
-    for &'tcx ty::List<Ty<'tcx>>
-{
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> chalk_ir::Substitution<RustInterner<'tcx>> {
-        chalk_ir::Substitution::from_iter(
-            interner,
-            self.iter().map(|ty| GenericArg::from(ty).lower_into(interner)),
-        )
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, SubstsRef<'tcx>> for &chalk_ir::Substitution<RustInterner<'tcx>> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> SubstsRef<'tcx> {
-        interner
-            .tcx
-            .mk_substs_from_iter(self.iter(interner).map(|subst| subst.lower_into(interner)))
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::InEnvironment<chalk_ir::Goal<RustInterner<'tcx>>>>
-    for ChalkEnvironmentAndGoal<'tcx>
-{
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> chalk_ir::InEnvironment<chalk_ir::Goal<RustInterner<'tcx>>> {
-        let clauses = self.environment.into_iter().map(|predicate| {
-            let (predicate, binders, _named_regions) =
-                collect_bound_vars(interner, interner.tcx, predicate.kind());
-            let consequence = match predicate {
-                ty::ClauseKind::TypeWellFormedFromEnv(ty) => {
-                    chalk_ir::DomainGoal::FromEnv(chalk_ir::FromEnv::Ty(ty.lower_into(interner)))
-                }
-                ty::ClauseKind::Trait(predicate) => chalk_ir::DomainGoal::FromEnv(
-                    chalk_ir::FromEnv::Trait(predicate.trait_ref.lower_into(interner)),
-                ),
-                ty::ClauseKind::RegionOutlives(predicate) => chalk_ir::DomainGoal::Holds(
-                    chalk_ir::WhereClause::LifetimeOutlives(chalk_ir::LifetimeOutlives {
-                        a: predicate.0.lower_into(interner),
-                        b: predicate.1.lower_into(interner),
-                    }),
-                ),
-                ty::ClauseKind::TypeOutlives(predicate) => chalk_ir::DomainGoal::Holds(
-                    chalk_ir::WhereClause::TypeOutlives(chalk_ir::TypeOutlives {
-                        ty: predicate.0.lower_into(interner),
-                        lifetime: predicate.1.lower_into(interner),
-                    }),
-                ),
-                ty::ClauseKind::Projection(predicate) => chalk_ir::DomainGoal::Holds(
-                    chalk_ir::WhereClause::AliasEq(predicate.lower_into(interner)),
-                ),
-                ty::ClauseKind::WellFormed(arg) => match arg.unpack() {
-                    ty::GenericArgKind::Type(ty) => chalk_ir::DomainGoal::WellFormed(
-                        chalk_ir::WellFormed::Ty(ty.lower_into(interner)),
-                    ),
-                    // FIXME(chalk): we need to change `WellFormed` in Chalk to take a `GenericArg`
-                    _ => chalk_ir::DomainGoal::WellFormed(chalk_ir::WellFormed::Ty(
-                        interner.tcx.types.unit.lower_into(interner),
-                    )),
-                },
-                ty::ClauseKind::ConstArgHasType(..) | ty::ClauseKind::ConstEvaluatable(_) => {
-                    bug!("unexpected predicate {}", predicate)
-                }
-            };
-            let value = chalk_ir::ProgramClauseImplication {
-                consequence,
-                conditions: chalk_ir::Goals::empty(interner),
-                priority: chalk_ir::ClausePriority::High,
-                constraints: chalk_ir::Constraints::empty(interner),
-            };
-            chalk_ir::ProgramClauseData(chalk_ir::Binders::new(binders, value)).intern(interner)
-        });
-
-        let goal: chalk_ir::GoalData<RustInterner<'tcx>> = self.goal.lower_into(interner);
-        chalk_ir::InEnvironment {
-            environment: chalk_ir::Environment {
-                clauses: chalk_ir::ProgramClauses::from_iter(interner, clauses),
-            },
-            goal: goal.intern(interner),
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::GoalData<RustInterner<'tcx>>> for ty::Predicate<'tcx> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::GoalData<RustInterner<'tcx>> {
-        let (predicate, binders, _named_regions) =
-            collect_bound_vars(interner, interner.tcx, self.kind());
-
-        let value = match predicate {
-            ty::PredicateKind::Clause(ty::ClauseKind::Trait(predicate)) => {
-                chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::Holds(
-                    chalk_ir::WhereClause::Implemented(predicate.trait_ref.lower_into(interner)),
-                ))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::RegionOutlives(predicate)) => {
-                chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::Holds(
-                    chalk_ir::WhereClause::LifetimeOutlives(chalk_ir::LifetimeOutlives {
-                        a: predicate.0.lower_into(interner),
-                        b: predicate.1.lower_into(interner),
-                    }),
-                ))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::TypeOutlives(predicate)) => {
-                chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::Holds(
-                    chalk_ir::WhereClause::TypeOutlives(chalk_ir::TypeOutlives {
-                        ty: predicate.0.lower_into(interner),
-                        lifetime: predicate.1.lower_into(interner),
-                    }),
-                ))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::Projection(predicate)) => {
-                chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::Holds(
-                    chalk_ir::WhereClause::AliasEq(predicate.lower_into(interner)),
-                ))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(arg)) => match arg.unpack() {
-                GenericArgKind::Type(ty) => match ty.kind() {
-                    // FIXME(chalk): In Chalk, a placeholder is WellFormed if it
-                    // `FromEnv`. However, when we "lower" Params, we don't update
-                    // the environment.
-                    ty::Placeholder(..) => {
-                        chalk_ir::GoalData::All(chalk_ir::Goals::empty(interner))
-                    }
-
-                    _ => chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::WellFormed(
-                        chalk_ir::WellFormed::Ty(ty.lower_into(interner)),
-                    )),
-                },
-                // FIXME(chalk): handle well formed consts
-                GenericArgKind::Const(..) => {
-                    chalk_ir::GoalData::All(chalk_ir::Goals::empty(interner))
-                }
-                GenericArgKind::Lifetime(lt) => bug!("unexpected well formed predicate: {:?}", lt),
-            },
-
-            ty::PredicateKind::ObjectSafe(t) => chalk_ir::GoalData::DomainGoal(
-                chalk_ir::DomainGoal::ObjectSafe(chalk_ir::TraitId(t)),
-            ),
-
-            ty::PredicateKind::Subtype(ty::SubtypePredicate { a, b, a_is_expected: _ }) => {
-                chalk_ir::GoalData::SubtypeGoal(chalk_ir::SubtypeGoal {
-                    a: a.lower_into(interner),
-                    b: b.lower_into(interner),
-                })
-            }
-
-            // FIXME(chalk): other predicates
-            //
-            // We can defer this, but ultimately we'll want to express
-            // some of these in terms of chalk operations.
-            ty::PredicateKind::ClosureKind(..)
-            | ty::PredicateKind::Clause(ty::ClauseKind::ConstArgHasType(..))
-            | ty::PredicateKind::AliasRelate(..)
-            | ty::PredicateKind::Coerce(..)
-            | ty::PredicateKind::Clause(ty::ClauseKind::ConstEvaluatable(..))
-            | ty::PredicateKind::Ambiguous
-            | ty::PredicateKind::ConstEquate(..) => {
-                chalk_ir::GoalData::All(chalk_ir::Goals::empty(interner))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(ty)) => {
-                chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::FromEnv(
-                    chalk_ir::FromEnv::Ty(ty.lower_into(interner)),
-                ))
-            }
-        };
-
-        chalk_ir::GoalData::Quantified(
-            chalk_ir::QuantifierKind::ForAll,
-            chalk_ir::Binders::new(binders, value.intern(interner)),
-        )
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::TraitRef<RustInterner<'tcx>>>
-    for rustc_middle::ty::TraitRef<'tcx>
-{
-    fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::TraitRef<RustInterner<'tcx>> {
-        chalk_ir::TraitRef {
-            trait_id: chalk_ir::TraitId(self.def_id),
-            substitution: self.substs.lower_into(interner),
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::AliasEq<RustInterner<'tcx>>>
-    for rustc_middle::ty::ProjectionPredicate<'tcx>
-{
-    fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::AliasEq<RustInterner<'tcx>> {
-        // FIXME(associated_const_equality): teach chalk about terms for alias eq.
-        chalk_ir::AliasEq {
-            ty: self.term.ty().unwrap().lower_into(interner),
-            alias: chalk_ir::AliasTy::Projection(chalk_ir::ProjectionTy {
-                associated_ty_id: chalk_ir::AssocTypeId(self.projection_ty.def_id),
-                substitution: self.projection_ty.substs.lower_into(interner),
-            }),
-        }
-    }
-}
-
-/*
-// FIXME(...): Where do I add this to Chalk? I can't find it in the rustc repo anywhere.
-impl<'tcx> LowerInto<'tcx, chalk_ir::Term<RustInterner<'tcx>>> for rustc_middle::ty::Term<'tcx> {
-  fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::Term<RustInterner<'tcx>> {
-    match self {
-      ty::Term::Ty(ty) => ty.lower_into(interner).into(),
-      ty::Term::Const(c) => c.lower_into(interner).into(),
-    }
-  }
-}
-*/
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::Ty<RustInterner<'tcx>>> for Ty<'tcx> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::Ty<RustInterner<'tcx>> {
-        let int = |i| chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Int(i));
-        let uint = |i| chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Uint(i));
-        let float = |f| chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Float(f));
-
-        match *self.kind() {
-            ty::Bool => chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Bool),
-            ty::Char => chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Char),
-            ty::Int(ty) => match ty {
-                ty::IntTy::Isize => int(chalk_ir::IntTy::Isize),
-                ty::IntTy::I8 => int(chalk_ir::IntTy::I8),
-                ty::IntTy::I16 => int(chalk_ir::IntTy::I16),
-                ty::IntTy::I32 => int(chalk_ir::IntTy::I32),
-                ty::IntTy::I64 => int(chalk_ir::IntTy::I64),
-                ty::IntTy::I128 => int(chalk_ir::IntTy::I128),
-            },
-            ty::Uint(ty) => match ty {
-                ty::UintTy::Usize => uint(chalk_ir::UintTy::Usize),
-                ty::UintTy::U8 => uint(chalk_ir::UintTy::U8),
-                ty::UintTy::U16 => uint(chalk_ir::UintTy::U16),
-                ty::UintTy::U32 => uint(chalk_ir::UintTy::U32),
-                ty::UintTy::U64 => uint(chalk_ir::UintTy::U64),
-                ty::UintTy::U128 => uint(chalk_ir::UintTy::U128),
-            },
-            ty::Float(ty) => match ty {
-                ty::FloatTy::F32 => float(chalk_ir::FloatTy::F32),
-                ty::FloatTy::F64 => float(chalk_ir::FloatTy::F64),
-            },
-            ty::Adt(def, substs) => {
-                chalk_ir::TyKind::Adt(chalk_ir::AdtId(def), substs.lower_into(interner))
-            }
-            ty::Foreign(def_id) => chalk_ir::TyKind::Foreign(ForeignDefId(def_id)),
-            ty::Str => chalk_ir::TyKind::Str,
-            ty::Array(ty, len) => {
-                chalk_ir::TyKind::Array(ty.lower_into(interner), len.lower_into(interner))
-            }
-            ty::Slice(ty) => chalk_ir::TyKind::Slice(ty.lower_into(interner)),
-
-            ty::RawPtr(ptr) => {
-                chalk_ir::TyKind::Raw(ptr.mutbl.lower_into(interner), ptr.ty.lower_into(interner))
-            }
-            ty::Ref(region, ty, mutability) => chalk_ir::TyKind::Ref(
-                mutability.lower_into(interner),
-                region.lower_into(interner),
-                ty.lower_into(interner),
-            ),
-            ty::FnDef(def_id, substs) => {
-                chalk_ir::TyKind::FnDef(chalk_ir::FnDefId(def_id), substs.lower_into(interner))
-            }
-            ty::FnPtr(sig) => {
-                let (inputs_and_outputs, binders, _named_regions) =
-                    collect_bound_vars(interner, interner.tcx, sig.inputs_and_output());
-                chalk_ir::TyKind::Function(chalk_ir::FnPointer {
-                    num_binders: binders.len(interner),
-                    sig: sig.lower_into(interner),
-                    substitution: chalk_ir::FnSubst(chalk_ir::Substitution::from_iter(
-                        interner,
-                        inputs_and_outputs.iter().map(|ty| {
-                            chalk_ir::GenericArgData::Ty(ty.lower_into(interner)).intern(interner)
-                        }),
-                    )),
-                })
-            }
-            // FIXME(dyn-star): handle the dynamic kind (dyn or dyn*)
-            ty::Dynamic(predicates, region, _kind) => chalk_ir::TyKind::Dyn(chalk_ir::DynTy {
-                bounds: predicates.lower_into(interner),
-                lifetime: region.lower_into(interner),
-            }),
-            ty::Closure(def_id, substs) => {
-                chalk_ir::TyKind::Closure(chalk_ir::ClosureId(def_id), substs.lower_into(interner))
-            }
-            ty::Generator(def_id, substs, _) => chalk_ir::TyKind::Generator(
-                chalk_ir::GeneratorId(def_id),
-                substs.lower_into(interner),
-            ),
-            ty::GeneratorWitness(_) => unimplemented!(),
-            ty::GeneratorWitnessMIR(..) => unimplemented!(),
-            ty::Never => chalk_ir::TyKind::Never,
-            ty::Tuple(types) => chalk_ir::TyKind::Tuple(types.len(), types.lower_into(interner)),
-            ty::Alias(ty::Projection, ty::AliasTy { def_id, substs, .. }) => {
-                chalk_ir::TyKind::Alias(chalk_ir::AliasTy::Projection(chalk_ir::ProjectionTy {
-                    associated_ty_id: chalk_ir::AssocTypeId(def_id),
-                    substitution: substs.lower_into(interner),
-                }))
-            }
-            ty::Alias(ty::Weak, ty::AliasTy { .. }) => unimplemented!(),
-            ty::Alias(ty::Inherent, _) => unimplemented!(),
-            ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs, .. }) => {
-                chalk_ir::TyKind::Alias(chalk_ir::AliasTy::Opaque(chalk_ir::OpaqueTy {
-                    opaque_ty_id: chalk_ir::OpaqueTyId(def_id),
-                    substitution: substs.lower_into(interner),
-                }))
-            }
-            // This should have been done eagerly prior to this, and all Params
-            // should have been substituted to placeholders
-            ty::Param(_) => panic!("Lowering Param when not expected."),
-            ty::Bound(db, bound) => chalk_ir::TyKind::BoundVar(chalk_ir::BoundVar::new(
-                chalk_ir::DebruijnIndex::new(db.as_u32()),
-                bound.var.index(),
-            )),
-            ty::Placeholder(_placeholder) => {
-                chalk_ir::TyKind::Placeholder(chalk_ir::PlaceholderIndex {
-                    ui: chalk_ir::UniverseIndex { counter: _placeholder.universe.as_usize() },
-                    idx: _placeholder.bound.var.as_usize(),
-                })
-            }
-            ty::Infer(_infer) => unimplemented!(),
-            ty::Error(_) => chalk_ir::TyKind::Error,
-        }
-        .intern(interner)
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, Ty<'tcx>> for &chalk_ir::Ty<RustInterner<'tcx>> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> Ty<'tcx> {
-        use chalk_ir::TyKind;
-
-        let kind = match self.kind(interner) {
-            TyKind::Adt(struct_id, substitution) => {
-                ty::Adt(struct_id.0, substitution.lower_into(interner))
-            }
-            TyKind::Scalar(scalar) => match scalar {
-                chalk_ir::Scalar::Bool => ty::Bool,
-                chalk_ir::Scalar::Char => ty::Char,
-                chalk_ir::Scalar::Int(int_ty) => match int_ty {
-                    chalk_ir::IntTy::Isize => ty::Int(ty::IntTy::Isize),
-                    chalk_ir::IntTy::I8 => ty::Int(ty::IntTy::I8),
-                    chalk_ir::IntTy::I16 => ty::Int(ty::IntTy::I16),
-                    chalk_ir::IntTy::I32 => ty::Int(ty::IntTy::I32),
-                    chalk_ir::IntTy::I64 => ty::Int(ty::IntTy::I64),
-                    chalk_ir::IntTy::I128 => ty::Int(ty::IntTy::I128),
-                },
-                chalk_ir::Scalar::Uint(int_ty) => match int_ty {
-                    chalk_ir::UintTy::Usize => ty::Uint(ty::UintTy::Usize),
-                    chalk_ir::UintTy::U8 => ty::Uint(ty::UintTy::U8),
-                    chalk_ir::UintTy::U16 => ty::Uint(ty::UintTy::U16),
-                    chalk_ir::UintTy::U32 => ty::Uint(ty::UintTy::U32),
-                    chalk_ir::UintTy::U64 => ty::Uint(ty::UintTy::U64),
-                    chalk_ir::UintTy::U128 => ty::Uint(ty::UintTy::U128),
-                },
-                chalk_ir::Scalar::Float(float_ty) => match float_ty {
-                    chalk_ir::FloatTy::F32 => ty::Float(ty::FloatTy::F32),
-                    chalk_ir::FloatTy::F64 => ty::Float(ty::FloatTy::F64),
-                },
-            },
-            TyKind::Array(ty, c) => {
-                let ty = ty.lower_into(interner);
-                let c = c.lower_into(interner);
-                ty::Array(ty, c)
-            }
-            TyKind::FnDef(id, substitution) => ty::FnDef(id.0, substitution.lower_into(interner)),
-            TyKind::Closure(closure, substitution) => {
-                ty::Closure(closure.0, substitution.lower_into(interner))
-            }
-            TyKind::Generator(generator, substitution) => ty::Generator(
-                generator.0,
-                substitution.lower_into(interner),
-                ast::Movability::Static,
-            ),
-            TyKind::GeneratorWitness(..) => unimplemented!(),
-            TyKind::Never => ty::Never,
-            TyKind::Tuple(_len, substitution) => {
-                ty::Tuple(substitution.lower_into(interner).into_type_list(interner.tcx))
-            }
-            TyKind::Slice(ty) => ty::Slice(ty.lower_into(interner)),
-            TyKind::Raw(mutbl, ty) => ty::RawPtr(ty::TypeAndMut {
-                ty: ty.lower_into(interner),
-                mutbl: mutbl.lower_into(interner),
-            }),
-            TyKind::Ref(mutbl, lifetime, ty) => ty::Ref(
-                lifetime.lower_into(interner),
-                ty.lower_into(interner),
-                mutbl.lower_into(interner),
-            ),
-            TyKind::Str => ty::Str,
-            TyKind::OpaqueType(opaque_ty, substitution) => ty::Alias(
-                ty::Opaque,
-                interner.tcx.mk_alias_ty(opaque_ty.0, substitution.lower_into(interner)),
-            ),
-            TyKind::AssociatedType(assoc_ty, substitution) => ty::Alias(
-                ty::Projection,
-                interner.tcx.mk_alias_ty(assoc_ty.0, substitution.lower_into(interner)),
-            ),
-            TyKind::Foreign(def_id) => ty::Foreign(def_id.0),
-            TyKind::Error => return interner.tcx.ty_error_misc(),
-            TyKind::Alias(alias_ty) => match alias_ty {
-                chalk_ir::AliasTy::Projection(projection) => ty::Alias(
-                    ty::Projection,
-                    interner.tcx.mk_alias_ty(
-                        projection.associated_ty_id.0,
-                        projection.substitution.lower_into(interner),
-                    ),
-                ),
-                chalk_ir::AliasTy::Opaque(opaque) => ty::Alias(
-                    ty::Opaque,
-                    interner.tcx.mk_alias_ty(
-                        opaque.opaque_ty_id.0,
-                        opaque.substitution.lower_into(interner),
-                    ),
-                ),
-            },
-            TyKind::Function(_quantified_ty) => unimplemented!(),
-            TyKind::BoundVar(bound) => ty::Bound(
-                ty::DebruijnIndex::from_usize(bound.debruijn.depth() as usize),
-                ty::BoundTy {
-                    var: ty::BoundVar::from_usize(bound.index),
-                    kind: ty::BoundTyKind::Anon,
-                },
-            ),
-            TyKind::Placeholder(placeholder) => ty::Placeholder(ty::Placeholder {
-                universe: ty::UniverseIndex::from_usize(placeholder.ui.counter),
-                bound: ty::BoundTy {
-                    var: ty::BoundVar::from_usize(placeholder.idx),
-                    kind: ty::BoundTyKind::Anon,
-                },
-            }),
-            TyKind::InferenceVar(_, _) => unimplemented!(),
-            TyKind::Dyn(_) => unimplemented!(),
-        };
-        interner.tcx.mk_ty_from_kind(kind)
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::Lifetime<RustInterner<'tcx>>> for Region<'tcx> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::Lifetime<RustInterner<'tcx>> {
-        match *self {
-            ty::ReEarlyBound(_) => {
-                panic!("Should have already been substituted.");
-            }
-            ty::ReError(_) => {
-                panic!("Error lifetime should not have already been lowered.");
-            }
-            ty::ReLateBound(db, br) => chalk_ir::LifetimeData::BoundVar(chalk_ir::BoundVar::new(
-                chalk_ir::DebruijnIndex::new(db.as_u32()),
-                br.var.as_usize(),
-            ))
-            .intern(interner),
-            ty::ReFree(_) => unimplemented!(),
-            ty::ReStatic => chalk_ir::LifetimeData::Static.intern(interner),
-            ty::ReVar(_) => unimplemented!(),
-            ty::RePlaceholder(placeholder_region) => {
-                chalk_ir::LifetimeData::Placeholder(chalk_ir::PlaceholderIndex {
-                    ui: chalk_ir::UniverseIndex { counter: placeholder_region.universe.index() },
-                    idx: 0, // FIXME: This `idx: 0` is sus.
-                })
-                .intern(interner)
-            }
-            ty::ReErased => chalk_ir::LifetimeData::Erased.intern(interner),
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, Region<'tcx>> for &chalk_ir::Lifetime<RustInterner<'tcx>> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> Region<'tcx> {
-        let tcx = interner.tcx;
-        match self.data(interner) {
-            chalk_ir::LifetimeData::BoundVar(var) => ty::Region::new_late_bound(
-                tcx,
-                ty::DebruijnIndex::from_u32(var.debruijn.depth()),
-                ty::BoundRegion {
-                    var: ty::BoundVar::from_usize(var.index),
-                    kind: ty::BrAnon(None),
-                },
-            ),
-            chalk_ir::LifetimeData::InferenceVar(_var) => unimplemented!(),
-            chalk_ir::LifetimeData::Placeholder(p) => ty::Region::new_placeholder(
-                tcx,
-                ty::Placeholder {
-                    universe: ty::UniverseIndex::from_usize(p.ui.counter),
-                    bound: ty::BoundRegion {
-                        var: ty::BoundVar::from_usize(p.idx),
-                        kind: ty::BoundRegionKind::BrAnon(None),
-                    },
-                },
-            ),
-            chalk_ir::LifetimeData::Static => tcx.lifetimes.re_static,
-            chalk_ir::LifetimeData::Erased => tcx.lifetimes.re_erased,
-            chalk_ir::LifetimeData::Phantom(void, _) => match *void {},
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::Const<RustInterner<'tcx>>> for ty::Const<'tcx> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::Const<RustInterner<'tcx>> {
-        let ty = self.ty().lower_into(interner);
-        let value = match self.kind() {
-            ty::ConstKind::Value(val) => {
-                chalk_ir::ConstValue::Concrete(chalk_ir::ConcreteConst { interned: val })
-            }
-            ty::ConstKind::Bound(db, bound) => chalk_ir::ConstValue::BoundVar(
-                chalk_ir::BoundVar::new(chalk_ir::DebruijnIndex::new(db.as_u32()), bound.index()),
-            ),
-            _ => unimplemented!("Const not implemented. {:?}", self),
-        };
-        chalk_ir::ConstData { ty, value }.intern(interner)
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, ty::Const<'tcx>> for &chalk_ir::Const<RustInterner<'tcx>> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> ty::Const<'tcx> {
-        let data = self.data(interner);
-        let ty = data.ty.lower_into(interner);
-        let kind = match data.value {
-            chalk_ir::ConstValue::BoundVar(var) => ty::ConstKind::Bound(
-                ty::DebruijnIndex::from_u32(var.debruijn.depth()),
-                ty::BoundVar::from_u32(var.index as u32),
-            ),
-            chalk_ir::ConstValue::InferenceVar(_var) => unimplemented!(),
-            chalk_ir::ConstValue::Placeholder(_p) => unimplemented!(),
-            chalk_ir::ConstValue::Concrete(c) => ty::ConstKind::Value(c.interned),
-        };
-        interner.tcx.mk_const(kind, ty)
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::GenericArg<RustInterner<'tcx>>> for GenericArg<'tcx> {
-    fn lower_into(self, interner: RustInterner<'tcx>) -> chalk_ir::GenericArg<RustInterner<'tcx>> {
-        match self.unpack() {
-            ty::subst::GenericArgKind::Type(ty) => {
-                chalk_ir::GenericArgData::Ty(ty.lower_into(interner))
-            }
-            ty::subst::GenericArgKind::Lifetime(lifetime) => {
-                chalk_ir::GenericArgData::Lifetime(lifetime.lower_into(interner))
-            }
-            ty::subst::GenericArgKind::Const(c) => {
-                chalk_ir::GenericArgData::Const(c.lower_into(interner))
-            }
-        }
-        .intern(interner)
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, ty::subst::GenericArg<'tcx>>
-    for &chalk_ir::GenericArg<RustInterner<'tcx>>
-{
-    fn lower_into(self, interner: RustInterner<'tcx>) -> ty::subst::GenericArg<'tcx> {
-        match self.data(interner) {
-            chalk_ir::GenericArgData::Ty(ty) => {
-                let t: Ty<'tcx> = ty.lower_into(interner);
-                t.into()
-            }
-            chalk_ir::GenericArgData::Lifetime(lifetime) => {
-                let r: Region<'tcx> = lifetime.lower_into(interner);
-                r.into()
-            }
-            chalk_ir::GenericArgData::Const(c) => {
-                let c: ty::Const<'tcx> = c.lower_into(interner);
-                c.into()
-            }
-        }
-    }
-}
-
-// We lower into an Option here since there are some predicates which Chalk
-// doesn't have a representation for yet (as a `WhereClause`), but are so common
-// that we just are accepting the unsoundness for now. The `Option` will
-// eventually be removed.
-impl<'tcx> LowerInto<'tcx, Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>
-    for ty::Predicate<'tcx>
-{
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>> {
-        let (predicate, binders, _named_regions) =
-            collect_bound_vars(interner, interner.tcx, self.kind());
-        let value = match predicate {
-            ty::PredicateKind::Clause(ty::ClauseKind::Trait(predicate)) => {
-                Some(chalk_ir::WhereClause::Implemented(predicate.trait_ref.lower_into(interner)))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::RegionOutlives(predicate)) => {
-                Some(chalk_ir::WhereClause::LifetimeOutlives(chalk_ir::LifetimeOutlives {
-                    a: predicate.0.lower_into(interner),
-                    b: predicate.1.lower_into(interner),
-                }))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::TypeOutlives(predicate)) => {
-                Some(chalk_ir::WhereClause::TypeOutlives(chalk_ir::TypeOutlives {
-                    ty: predicate.0.lower_into(interner),
-                    lifetime: predicate.1.lower_into(interner),
-                }))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::Projection(predicate)) => {
-                Some(chalk_ir::WhereClause::AliasEq(predicate.lower_into(interner)))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(_ty)) => None,
-            ty::PredicateKind::Clause(ty::ClauseKind::ConstArgHasType(..)) => None,
-
-            ty::PredicateKind::ObjectSafe(..)
-            | ty::PredicateKind::AliasRelate(..)
-            | ty::PredicateKind::ClosureKind(..)
-            | ty::PredicateKind::Subtype(..)
-            | ty::PredicateKind::Coerce(..)
-            | ty::PredicateKind::Clause(ty::ClauseKind::ConstEvaluatable(..))
-            | ty::PredicateKind::ConstEquate(..)
-            | ty::PredicateKind::Ambiguous
-            | ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                bug!("unexpected predicate {self}")
-            }
-        };
-        value.map(|value| chalk_ir::Binders::new(binders, value))
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::Binders<chalk_ir::QuantifiedWhereClauses<RustInterner<'tcx>>>>
-    for &'tcx ty::List<ty::PolyExistentialPredicate<'tcx>>
-{
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> chalk_ir::Binders<chalk_ir::QuantifiedWhereClauses<RustInterner<'tcx>>> {
-        // `Self` has one binder:
-        // Binder<&'tcx ty::List<ty::ExistentialPredicate<'tcx>>>
-        // The return type has two:
-        // Binders<&[Binders<WhereClause<I>>]>
-        // This means that any variables that are escaping `self` need to be
-        // shifted in by one so that they are still escaping.
-        let predicates = ty::fold::shift_vars(interner.tcx, self, 1);
-
-        let self_ty = interner.tcx.mk_bound(
-            // This is going to be wrapped in a binder
-            ty::DebruijnIndex::from_usize(1),
-            ty::BoundTy { var: ty::BoundVar::from_usize(0), kind: ty::BoundTyKind::Anon },
-        );
-        let where_clauses = predicates.into_iter().map(|predicate| {
-            let (predicate, binders, _named_regions) =
-                collect_bound_vars(interner, interner.tcx, predicate);
-            match predicate {
-                ty::ExistentialPredicate::Trait(ty::ExistentialTraitRef { def_id, substs }) => {
-                    chalk_ir::Binders::new(
-                        binders.clone(),
-                        chalk_ir::WhereClause::Implemented(chalk_ir::TraitRef {
-                            trait_id: chalk_ir::TraitId(def_id),
-                            substitution: interner
-                                .tcx
-                                .mk_substs_trait(self_ty, substs)
-                                .lower_into(interner),
-                        }),
-                    )
-                }
-                ty::ExistentialPredicate::Projection(predicate) => chalk_ir::Binders::new(
-                    binders.clone(),
-                    chalk_ir::WhereClause::AliasEq(chalk_ir::AliasEq {
-                        alias: chalk_ir::AliasTy::Projection(chalk_ir::ProjectionTy {
-                            associated_ty_id: chalk_ir::AssocTypeId(predicate.def_id),
-                            substitution: interner
-                                .tcx
-                                .mk_substs_trait(self_ty, predicate.substs)
-                                .lower_into(interner),
-                        }),
-                        // FIXME(associated_const_equality): teach chalk about terms for alias eq.
-                        ty: predicate.term.ty().unwrap().lower_into(interner),
-                    }),
-                ),
-                ty::ExistentialPredicate::AutoTrait(def_id) => chalk_ir::Binders::new(
-                    binders.clone(),
-                    chalk_ir::WhereClause::Implemented(chalk_ir::TraitRef {
-                        trait_id: chalk_ir::TraitId(def_id),
-                        substitution: interner
-                            .tcx
-                            .mk_substs_trait(self_ty, [])
-                            .lower_into(interner),
-                    }),
-                ),
-            }
-        });
-
-        // Binder for the bound variable representing the concrete underlying type.
-        let existential_binder = chalk_ir::VariableKinds::from1(
-            interner,
-            chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General),
-        );
-        let value = chalk_ir::QuantifiedWhereClauses::from_iter(interner, where_clauses);
-        chalk_ir::Binders::new(existential_binder, value)
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::FnSig<RustInterner<'tcx>>>
-    for ty::Binder<'tcx, ty::FnSig<'tcx>>
-{
-    fn lower_into(self, _interner: RustInterner<'_>) -> FnSig<RustInterner<'tcx>> {
-        chalk_ir::FnSig {
-            abi: self.abi(),
-            safety: match self.unsafety() {
-                Unsafety::Normal => chalk_ir::Safety::Safe,
-                Unsafety::Unsafe => chalk_ir::Safety::Unsafe,
-            },
-            variadic: self.c_variadic(),
-        }
-    }
-}
-
-// We lower into an Option here since there are some predicates which Chalk
-// doesn't have a representation for yet (as an `InlineBound`). The `Option` will
-// eventually be removed.
-impl<'tcx> LowerInto<'tcx, Option<chalk_solve::rust_ir::QuantifiedInlineBound<RustInterner<'tcx>>>>
-    for ty::Predicate<'tcx>
-{
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> Option<chalk_solve::rust_ir::QuantifiedInlineBound<RustInterner<'tcx>>> {
-        let (predicate, binders, _named_regions) =
-            collect_bound_vars(interner, interner.tcx, self.kind());
-        match predicate {
-            ty::PredicateKind::Clause(ty::ClauseKind::Trait(predicate)) => {
-                Some(chalk_ir::Binders::new(
-                    binders,
-                    chalk_solve::rust_ir::InlineBound::TraitBound(
-                        predicate.trait_ref.lower_into(interner),
-                    ),
-                ))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::Projection(predicate)) => {
-                Some(chalk_ir::Binders::new(
-                    binders,
-                    chalk_solve::rust_ir::InlineBound::AliasEqBound(predicate.lower_into(interner)),
-                ))
-            }
-            ty::PredicateKind::Clause(ty::ClauseKind::TypeOutlives(_predicate)) => None,
-            ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(_ty)) => None,
-            ty::PredicateKind::Clause(ty::ClauseKind::ConstArgHasType(..)) => None,
-
-            ty::PredicateKind::Clause(ty::ClauseKind::RegionOutlives(..))
-            | ty::PredicateKind::AliasRelate(..)
-            | ty::PredicateKind::ObjectSafe(..)
-            | ty::PredicateKind::ClosureKind(..)
-            | ty::PredicateKind::Subtype(..)
-            | ty::PredicateKind::Coerce(..)
-            | ty::PredicateKind::Clause(ty::ClauseKind::ConstEvaluatable(..))
-            | ty::PredicateKind::ConstEquate(..)
-            | ty::PredicateKind::Ambiguous
-            | ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {
-                bug!("unexpected predicate {}", &self)
-            }
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_solve::rust_ir::TraitBound<RustInterner<'tcx>>>
-    for ty::TraitRef<'tcx>
-{
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> chalk_solve::rust_ir::TraitBound<RustInterner<'tcx>> {
-        chalk_solve::rust_ir::TraitBound {
-            trait_id: chalk_ir::TraitId(self.def_id),
-            args_no_self: self.substs[1..].iter().map(|arg| arg.lower_into(interner)).collect(),
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_ir::Mutability> for ast::Mutability {
-    fn lower_into(self, _interner: RustInterner<'tcx>) -> chalk_ir::Mutability {
-        match self {
-            rustc_ast::Mutability::Mut => chalk_ir::Mutability::Mut,
-            rustc_ast::Mutability::Not => chalk_ir::Mutability::Not,
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, ast::Mutability> for chalk_ir::Mutability {
-    fn lower_into(self, _interner: RustInterner<'tcx>) -> ast::Mutability {
-        match self {
-            chalk_ir::Mutability::Mut => ast::Mutability::Mut,
-            chalk_ir::Mutability::Not => ast::Mutability::Not,
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_solve::rust_ir::Polarity> for ty::ImplPolarity {
-    fn lower_into(self, _interner: RustInterner<'tcx>) -> chalk_solve::rust_ir::Polarity {
-        match self {
-            ty::ImplPolarity::Positive => chalk_solve::rust_ir::Polarity::Positive,
-            ty::ImplPolarity::Negative => chalk_solve::rust_ir::Polarity::Negative,
-            // FIXME(chalk) reservation impls
-            ty::ImplPolarity::Reservation => chalk_solve::rust_ir::Polarity::Negative,
-        }
-    }
-}
-impl<'tcx> LowerInto<'tcx, chalk_ir::Variance> for ty::Variance {
-    fn lower_into(self, _interner: RustInterner<'tcx>) -> chalk_ir::Variance {
-        match self {
-            ty::Variance::Covariant => chalk_ir::Variance::Covariant,
-            ty::Variance::Invariant => chalk_ir::Variance::Invariant,
-            ty::Variance::Contravariant => chalk_ir::Variance::Contravariant,
-            ty::Variance::Bivariant => unimplemented!(),
-        }
-    }
-}
-
-impl<'tcx> LowerInto<'tcx, chalk_solve::rust_ir::AliasEqBound<RustInterner<'tcx>>>
-    for ty::ProjectionPredicate<'tcx>
-{
-    fn lower_into(
-        self,
-        interner: RustInterner<'tcx>,
-    ) -> chalk_solve::rust_ir::AliasEqBound<RustInterner<'tcx>> {
-        let (trait_ref, own_substs) = self.projection_ty.trait_ref_and_own_substs(interner.tcx);
-        chalk_solve::rust_ir::AliasEqBound {
-            trait_bound: trait_ref.lower_into(interner),
-            associated_ty_id: chalk_ir::AssocTypeId(self.projection_ty.def_id),
-            parameters: own_substs.iter().map(|arg| arg.lower_into(interner)).collect(),
-            value: self.term.ty().unwrap().lower_into(interner),
-        }
-    }
-}
-
-/// To collect bound vars, we have to do two passes. In the first pass, we
-/// collect all `BoundRegionKind`s and `ty::Bound`s. In the second pass, we then
-/// replace `BrNamed` into `BrAnon`. The two separate passes are important,
-/// since we can only replace `BrNamed` with `BrAnon`s with indices *after* all
-/// "real" `BrAnon`s.
-///
-/// It's important to note that because of prior substitution, we may have
-/// late-bound regions, even outside of fn contexts, since this is the best way
-/// to prep types for chalk lowering.
-pub(crate) fn collect_bound_vars<'tcx, T: TypeFoldable<TyCtxt<'tcx>>>(
-    interner: RustInterner<'tcx>,
-    tcx: TyCtxt<'tcx>,
-    ty: Binder<'tcx, T>,
-) -> (T, chalk_ir::VariableKinds<RustInterner<'tcx>>, BTreeMap<DefId, u32>) {
-    let mut bound_vars_collector = BoundVarsCollector::new();
-    ty.as_ref().skip_binder().visit_with(&mut bound_vars_collector);
-    let mut parameters = bound_vars_collector.parameters;
-    let named_parameters: BTreeMap<DefId, u32> = bound_vars_collector
-        .named_parameters
-        .into_iter()
-        .enumerate()
-        .map(|(i, def_id)| (def_id, (i + parameters.len()) as u32))
-        .collect();
-
-    let mut bound_var_substitutor = NamedBoundVarSubstitutor::new(tcx, &named_parameters);
-    let new_ty = ty.skip_binder().fold_with(&mut bound_var_substitutor);
-
-    for var in named_parameters.values() {
-        parameters.insert(*var, chalk_ir::VariableKind::Lifetime);
-    }
-
-    (0..parameters.len()).for_each(|i| {
-        parameters
-            .get(&(i as u32))
-            .or_else(|| bug!("Skipped bound var index: parameters={:?}", parameters));
-    });
-
-    let binders = chalk_ir::VariableKinds::from_iter(interner, parameters.into_values());
-
-    (new_ty, binders, named_parameters)
-}
-
-pub(crate) struct BoundVarsCollector<'tcx> {
-    binder_index: ty::DebruijnIndex,
-    pub(crate) parameters: BTreeMap<u32, chalk_ir::VariableKind<RustInterner<'tcx>>>,
-    pub(crate) named_parameters: Vec<DefId>,
-}
-
-impl<'tcx> BoundVarsCollector<'tcx> {
-    pub(crate) fn new() -> Self {
-        BoundVarsCollector {
-            binder_index: ty::INNERMOST,
-            parameters: BTreeMap::new(),
-            named_parameters: vec![],
-        }
-    }
-}
-
-impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for BoundVarsCollector<'tcx> {
-    fn visit_binder<T: TypeVisitable<TyCtxt<'tcx>>>(
-        &mut self,
-        t: &Binder<'tcx, T>,
-    ) -> ControlFlow<Self::BreakTy> {
-        self.binder_index.shift_in(1);
-        let result = t.super_visit_with(self);
-        self.binder_index.shift_out(1);
-        result
-    }
-
-    fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
-        match *t.kind() {
-            ty::Bound(debruijn, bound_ty) if debruijn == self.binder_index => {
-                match self.parameters.entry(bound_ty.var.as_u32()) {
-                    Entry::Vacant(entry) => {
-                        entry.insert(chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General));
-                    }
-                    Entry::Occupied(entry) => match entry.get() {
-                        chalk_ir::VariableKind::Ty(_) => {}
-                        _ => panic!(),
-                    },
-                }
-            }
-
-            _ => (),
-        };
-
-        t.super_visit_with(self)
-    }
-
-    fn visit_region(&mut self, r: Region<'tcx>) -> ControlFlow<Self::BreakTy> {
-        match *r {
-            ty::ReLateBound(index, br) if index == self.binder_index => match br.kind {
-                ty::BoundRegionKind::BrNamed(def_id, _name) => {
-                    if !self.named_parameters.iter().any(|d| *d == def_id) {
-                        self.named_parameters.push(def_id);
-                    }
-                }
-
-                ty::BoundRegionKind::BrAnon(_) => match self.parameters.entry(br.var.as_u32()) {
-                    Entry::Vacant(entry) => {
-                        entry.insert(chalk_ir::VariableKind::Lifetime);
-                    }
-                    Entry::Occupied(entry) => match entry.get() {
-                        chalk_ir::VariableKind::Lifetime => {}
-                        _ => panic!(),
-                    },
-                },
-
-                ty::BoundRegionKind::BrEnv => unimplemented!(),
-            },
-
-            ty::ReEarlyBound(_re) => {
-                // FIXME(chalk): jackh726 - I think we should always have already
-                // substituted away `ReEarlyBound`s for `ReLateBound`s, but need to confirm.
-                unimplemented!();
-            }
-
-            _ => (),
-        };
-
-        ControlFlow::Continue(())
-    }
-}
-
-/// This is used to replace `BoundRegionKind::BrNamed` with `BoundRegionKind::BrAnon`.
-/// Note: we assume that we will always have room for more bound vars. (i.e. we
-/// won't ever hit the `u32` limit in `BrAnon`s).
-struct NamedBoundVarSubstitutor<'a, 'tcx> {
-    tcx: TyCtxt<'tcx>,
-    binder_index: ty::DebruijnIndex,
-    named_parameters: &'a BTreeMap<DefId, u32>,
-}
-
-impl<'a, 'tcx> NamedBoundVarSubstitutor<'a, 'tcx> {
-    fn new(tcx: TyCtxt<'tcx>, named_parameters: &'a BTreeMap<DefId, u32>) -> Self {
-        NamedBoundVarSubstitutor { tcx, binder_index: ty::INNERMOST, named_parameters }
-    }
-}
-
-impl<'a, 'tcx> TypeFolder<TyCtxt<'tcx>> for NamedBoundVarSubstitutor<'a, 'tcx> {
-    fn interner(&self) -> TyCtxt<'tcx> {
-        self.tcx
-    }
-
-    fn fold_binder<T: TypeFoldable<TyCtxt<'tcx>>>(
-        &mut self,
-        t: Binder<'tcx, T>,
-    ) -> Binder<'tcx, T> {
-        self.binder_index.shift_in(1);
-        let result = t.super_fold_with(self);
-        self.binder_index.shift_out(1);
-        result
-    }
-
-    fn fold_region(&mut self, r: Region<'tcx>) -> Region<'tcx> {
-        match *r {
-            ty::ReLateBound(index, br) if index == self.binder_index => match br.kind {
-                ty::BrNamed(def_id, _name) => match self.named_parameters.get(&def_id) {
-                    Some(_) => {
-                        let new_br = ty::BoundRegion { var: br.var, kind: ty::BrAnon(None) };
-                        return ty::Region::new_late_bound(self.tcx, index, new_br);
-                    }
-                    None => panic!("Missing `BrNamed`."),
-                },
-                ty::BrEnv => unimplemented!(),
-                ty::BrAnon(..) => {}
-            },
-            _ => (),
-        };
-
-        r
-    }
-}
-
-/// Used to substitute `Param`s with placeholders. We do this since Chalk
-/// have a notion of `Param`s.
-pub(crate) struct ParamsSubstitutor<'tcx> {
-    tcx: TyCtxt<'tcx>,
-    binder_index: ty::DebruijnIndex,
-    list: Vec<rustc_middle::ty::ParamTy>,
-    next_ty_placeholder: usize,
-    pub(crate) params: rustc_data_structures::fx::FxHashMap<u32, rustc_middle::ty::ParamTy>,
-    pub(crate) named_regions: BTreeMap<DefId, u32>,
-}
-
-impl<'tcx> ParamsSubstitutor<'tcx> {
-    pub(crate) fn new(tcx: TyCtxt<'tcx>, next_ty_placeholder: usize) -> Self {
-        ParamsSubstitutor {
-            tcx,
-            binder_index: ty::INNERMOST,
-            list: vec![],
-            next_ty_placeholder,
-            params: rustc_data_structures::fx::FxHashMap::default(),
-            named_regions: BTreeMap::default(),
-        }
-    }
-}
-
-impl<'tcx> TypeFolder<TyCtxt<'tcx>> for ParamsSubstitutor<'tcx> {
-    fn interner(&self) -> TyCtxt<'tcx> {
-        self.tcx
-    }
-
-    fn fold_binder<T: TypeFoldable<TyCtxt<'tcx>>>(
-        &mut self,
-        t: Binder<'tcx, T>,
-    ) -> Binder<'tcx, T> {
-        self.binder_index.shift_in(1);
-        let result = t.super_fold_with(self);
-        self.binder_index.shift_out(1);
-        result
-    }
-
-    fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
-        match *t.kind() {
-            ty::Param(param) => match self.list.iter().position(|r| r == &param) {
-                Some(idx) => self.tcx.mk_placeholder(ty::PlaceholderType {
-                    universe: ty::UniverseIndex::from_usize(0),
-                    bound: ty::BoundTy {
-                        var: ty::BoundVar::from_usize(idx),
-                        kind: ty::BoundTyKind::Anon,
-                    },
-                }),
-                None => {
-                    self.list.push(param);
-                    let idx = self.list.len() - 1 + self.next_ty_placeholder;
-                    self.params.insert(idx as u32, param);
-                    self.tcx.mk_placeholder(ty::PlaceholderType {
-                        universe: ty::UniverseIndex::from_usize(0),
-                        bound: ty::BoundTy {
-                            var: ty::BoundVar::from_usize(idx),
-                            kind: ty::BoundTyKind::Anon,
-                        },
-                    })
-                }
-            },
-            _ => t.super_fold_with(self),
-        }
-    }
-
-    fn fold_region(&mut self, r: Region<'tcx>) -> Region<'tcx> {
-        match *r {
-            // FIXME(chalk) - jackh726 - this currently isn't hit in any tests,
-            // since canonicalization will already change these to canonical
-            // variables (ty::ReLateBound).
-            ty::ReEarlyBound(_re) => match self.named_regions.get(&_re.def_id) {
-                Some(idx) => {
-                    let br = ty::BoundRegion {
-                        var: ty::BoundVar::from_u32(*idx),
-                        kind: ty::BrAnon(None),
-                    };
-                    ty::Region::new_late_bound(self.tcx, self.binder_index, br)
-                }
-                None => {
-                    let idx = self.named_regions.len() as u32;
-                    let br = ty::BoundRegion {
-                        var: ty::BoundVar::from_u32(idx),
-                        kind: ty::BrAnon(None),
-                    };
-                    self.named_regions.insert(_re.def_id, idx);
-                    ty::Region::new_late_bound(self.tcx, self.binder_index, br)
-                }
-            },
-
-            _ => r,
-        }
-    }
-}
-
-pub(crate) struct ReverseParamsSubstitutor<'tcx> {
-    tcx: TyCtxt<'tcx>,
-    params: rustc_data_structures::fx::FxHashMap<u32, rustc_middle::ty::ParamTy>,
-}
-
-impl<'tcx> ReverseParamsSubstitutor<'tcx> {
-    pub(crate) fn new(
-        tcx: TyCtxt<'tcx>,
-        params: rustc_data_structures::fx::FxHashMap<u32, rustc_middle::ty::ParamTy>,
-    ) -> Self {
-        Self { tcx, params }
-    }
-}
-
-impl<'tcx> TypeFolder<TyCtxt<'tcx>> for ReverseParamsSubstitutor<'tcx> {
-    fn interner(&self) -> TyCtxt<'tcx> {
-        self.tcx
-    }
-
-    fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
-        match *t.kind() {
-            ty::Placeholder(ty::PlaceholderType { universe: ty::UniverseIndex::ROOT, bound }) => {
-                match self.params.get(&bound.var.as_u32()) {
-                    Some(&ty::ParamTy { index, name }) => self.tcx.mk_ty_param(index, name),
-                    None => t,
-                }
-            }
-
-            _ => t.super_fold_with(self),
-        }
-    }
-}
-
-/// Used to collect `Placeholder`s.
-pub(crate) struct PlaceholdersCollector {
-    universe_index: ty::UniverseIndex,
-    pub(crate) next_ty_placeholder: usize,
-    pub(crate) next_anon_region_placeholder: u32,
-}
-
-impl PlaceholdersCollector {
-    pub(crate) fn new() -> Self {
-        PlaceholdersCollector {
-            universe_index: ty::UniverseIndex::ROOT,
-            next_ty_placeholder: 0,
-            next_anon_region_placeholder: 0,
-        }
-    }
-}
-
-impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for PlaceholdersCollector {
-    fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
-        match t.kind() {
-            ty::Placeholder(p) if p.universe == self.universe_index => {
-                self.next_ty_placeholder = self.next_ty_placeholder.max(p.bound.var.as_usize() + 1);
-            }
-
-            _ => (),
-        };
-
-        t.super_visit_with(self)
-    }
-
-    fn visit_region(&mut self, r: Region<'tcx>) -> ControlFlow<Self::BreakTy> {
-        match *r {
-            ty::RePlaceholder(p) if p.universe == self.universe_index => {
-                if let ty::BoundRegionKind::BrAnon(_) = p.bound.kind {
-                    self.next_anon_region_placeholder =
-                        self.next_anon_region_placeholder.max(p.bound.var.as_u32());
-                }
-                // FIXME: This doesn't seem to handle BrNamed at all?
-            }
-
-            _ => (),
-        };
-
-        ControlFlow::Continue(())
-    }
-}
diff --git a/compiler/rustc_traits/src/chalk/mod.rs b/compiler/rustc_traits/src/chalk/mod.rs
deleted file mode 100644
index 8834449c9a4..00000000000
--- a/compiler/rustc_traits/src/chalk/mod.rs
+++ /dev/null
@@ -1,169 +0,0 @@
-//! Calls `chalk-solve` to solve a `ty::Predicate`
-//!
-//! In order to call `chalk-solve`, this file must convert a `CanonicalChalkEnvironmentAndGoal` into
-//! a Chalk uncanonical goal. It then calls Chalk, and converts the answer back into rustc solution.
-
-pub(crate) mod db;
-pub(crate) mod lowering;
-
-use rustc_middle::infer::canonical::{CanonicalTyVarKind, CanonicalVarKind};
-use rustc_middle::query::Providers;
-use rustc_middle::traits::ChalkRustInterner;
-use rustc_middle::ty::{self, TyCtxt, TypeFoldable, TypeVisitable};
-
-use rustc_infer::infer::canonical::{
-    Canonical, CanonicalVarValues, Certainty, QueryRegionConstraints, QueryResponse,
-};
-use rustc_infer::traits::{self, CanonicalChalkEnvironmentAndGoal};
-
-use crate::chalk::db::RustIrDatabase as ChalkRustIrDatabase;
-use crate::chalk::lowering::LowerInto;
-use crate::chalk::lowering::{ParamsSubstitutor, PlaceholdersCollector, ReverseParamsSubstitutor};
-
-use chalk_solve::Solution;
-
-pub(crate) fn provide(p: &mut Providers) {
-    *p = Providers { evaluate_goal, ..*p };
-}
-
-pub(crate) fn evaluate_goal<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    obligation: CanonicalChalkEnvironmentAndGoal<'tcx>,
-) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, traits::query::NoSolution> {
-    let interner = ChalkRustInterner { tcx };
-
-    // Chalk doesn't have a notion of `Params`, so instead we use placeholders.
-    let mut placeholders_collector = PlaceholdersCollector::new();
-    obligation.visit_with(&mut placeholders_collector);
-
-    let mut params_substitutor =
-        ParamsSubstitutor::new(tcx, placeholders_collector.next_ty_placeholder);
-    let obligation = obligation.fold_with(&mut params_substitutor);
-    let params = params_substitutor.params;
-
-    let max_universe = obligation.max_universe.index();
-
-    let lowered_goal: chalk_ir::UCanonical<
-        chalk_ir::InEnvironment<chalk_ir::Goal<ChalkRustInterner<'tcx>>>,
-    > = chalk_ir::UCanonical {
-        canonical: chalk_ir::Canonical {
-            binders: chalk_ir::CanonicalVarKinds::from_iter(
-                interner,
-                obligation.variables.iter().map(|v| match v.kind {
-                    CanonicalVarKind::PlaceholderTy(_ty) => unimplemented!(),
-                    CanonicalVarKind::PlaceholderRegion(_ui) => unimplemented!(),
-                    CanonicalVarKind::Ty(ty) => match ty {
-                        CanonicalTyVarKind::General(ui) => chalk_ir::WithKind::new(
-                            chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General),
-                            chalk_ir::UniverseIndex { counter: ui.index() },
-                        ),
-                        CanonicalTyVarKind::Int => chalk_ir::WithKind::new(
-                            chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::Integer),
-                            chalk_ir::UniverseIndex::root(),
-                        ),
-                        CanonicalTyVarKind::Float => chalk_ir::WithKind::new(
-                            chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::Float),
-                            chalk_ir::UniverseIndex::root(),
-                        ),
-                    },
-                    CanonicalVarKind::Region(ui) => chalk_ir::WithKind::new(
-                        chalk_ir::VariableKind::Lifetime,
-                        chalk_ir::UniverseIndex { counter: ui.index() },
-                    ),
-                    CanonicalVarKind::Const(_ui, _ty) => unimplemented!(),
-                    CanonicalVarKind::PlaceholderConst(_pc, _ty) => unimplemented!(),
-                }),
-            ),
-            value: obligation.value.lower_into(interner),
-        },
-        universes: max_universe + 1,
-    };
-
-    use chalk_solve::Solver;
-    let mut solver = chalk_engine::solve::SLGSolver::new(32, None);
-    let db = ChalkRustIrDatabase { interner };
-    debug!(?lowered_goal);
-    let solution = solver.solve(&db, &lowered_goal);
-    debug!(?obligation, ?solution, "evaluate goal");
-
-    // Ideally, the code to convert *back* to rustc types would live close to
-    // the code to convert *from* rustc types. Right now though, we don't
-    // really need this and so it's really minimal.
-    // Right now, we also treat a `Unique` solution the same as
-    // `Ambig(Definite)`. This really isn't right.
-    let make_solution = |subst: chalk_ir::Substitution<_>,
-                         binders: chalk_ir::CanonicalVarKinds<_>| {
-        use rustc_middle::infer::canonical::CanonicalVarInfo;
-
-        let mut reverse_param_substitutor = ReverseParamsSubstitutor::new(tcx, params);
-        let var_values = tcx.mk_substs_from_iter(
-            subst
-                .as_slice(interner)
-                .iter()
-                .map(|p| p.lower_into(interner).fold_with(&mut reverse_param_substitutor)),
-        );
-        let variables = binders.iter(interner).map(|var| {
-            let kind = match var.kind {
-                chalk_ir::VariableKind::Ty(ty_kind) => CanonicalVarKind::Ty(match ty_kind {
-                    chalk_ir::TyVariableKind::General => CanonicalTyVarKind::General(
-                        ty::UniverseIndex::from_usize(var.skip_kind().counter),
-                    ),
-                    chalk_ir::TyVariableKind::Integer => CanonicalTyVarKind::Int,
-                    chalk_ir::TyVariableKind::Float => CanonicalTyVarKind::Float,
-                }),
-                chalk_ir::VariableKind::Lifetime => {
-                    CanonicalVarKind::Region(ty::UniverseIndex::from_usize(var.skip_kind().counter))
-                }
-                // FIXME(compiler-errors): We don't currently have a way of turning
-                // a Chalk ty back into a rustc ty, right?
-                chalk_ir::VariableKind::Const(_) => todo!(),
-            };
-            CanonicalVarInfo { kind }
-        });
-        let max_universe = binders.iter(interner).map(|v| v.skip_kind().counter).max().unwrap_or(0);
-        let sol = Canonical {
-            max_universe: ty::UniverseIndex::from_usize(max_universe),
-            variables: tcx.mk_canonical_var_infos_from_iter(variables),
-            value: QueryResponse {
-                var_values: CanonicalVarValues { var_values },
-                region_constraints: QueryRegionConstraints::default(),
-                certainty: Certainty::Proven,
-                opaque_types: vec![],
-                value: (),
-            },
-        };
-        tcx.arena.alloc(sol)
-    };
-    solution
-        .map(|s| match s {
-            Solution::Unique(subst) => {
-                // FIXME(chalk): handle constraints
-                make_solution(subst.value.subst, subst.binders)
-            }
-            Solution::Ambig(guidance) => {
-                match guidance {
-                    chalk_solve::Guidance::Definite(subst) => {
-                        make_solution(subst.value, subst.binders)
-                    }
-                    chalk_solve::Guidance::Suggested(_) => unimplemented!(),
-                    chalk_solve::Guidance::Unknown => {
-                        // chalk_fulfill doesn't use the var_values here, so
-                        // let's just ignore that
-                        let sol = Canonical {
-                            max_universe: ty::UniverseIndex::from_usize(0),
-                            variables: obligation.variables,
-                            value: QueryResponse {
-                                var_values: CanonicalVarValues::dummy(),
-                                region_constraints: QueryRegionConstraints::default(),
-                                certainty: Certainty::Ambiguous,
-                                opaque_types: vec![],
-                                value: (),
-                            },
-                        };
-                        &*tcx.arena.alloc(sol)
-                    }
-                }
-            }
-        })
-        .ok_or(traits::query::NoSolution)
-}
diff --git a/compiler/rustc_traits/src/lib.rs b/compiler/rustc_traits/src/lib.rs
index 590d0bd0e42..dfa5814219b 100644
--- a/compiler/rustc_traits/src/lib.rs
+++ b/compiler/rustc_traits/src/lib.rs
@@ -1,5 +1,4 @@
-//! New recursive solver modeled on Chalk's recursive solver. Most of
-//! the guts are broken up into modules; see the comments in those modules.
+//! Queries that are independent from the main solver code.
 
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
@@ -11,7 +10,6 @@ extern crate tracing;
 #[macro_use]
 extern crate rustc_middle;
 
-mod chalk;
 mod codegen;
 mod dropck_outlives;
 mod evaluate_obligation;
@@ -29,7 +27,6 @@ pub fn provide(p: &mut Providers) {
     dropck_outlives::provide(p);
     evaluate_obligation::provide(p);
     implied_outlives_bounds::provide(p);
-    chalk::provide(p);
     normalize_projection_ty::provide(p);
     normalize_erasing_regions::provide(p);
     type_op::provide(p);
diff --git a/compiler/rustc_traits/src/normalize_erasing_regions.rs b/compiler/rustc_traits/src/normalize_erasing_regions.rs
index b83abf98592..2563e3ed1a3 100644
--- a/compiler/rustc_traits/src/normalize_erasing_regions.rs
+++ b/compiler/rustc_traits/src/normalize_erasing_regions.rs
@@ -69,7 +69,6 @@ fn not_outlives_predicate(p: ty::Predicate<'_>) -> bool {
         | ty::PredicateKind::Coerce(..)
         | ty::PredicateKind::Clause(ty::ClauseKind::ConstEvaluatable(..))
         | ty::PredicateKind::ConstEquate(..)
-        | ty::PredicateKind::Ambiguous
-        | ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => true,
+        | ty::PredicateKind::Ambiguous => true,
     }
 }
diff --git a/compiler/rustc_ty_utils/src/ty.rs b/compiler/rustc_ty_utils/src/ty.rs
index d5ebcda8a6c..620db143582 100644
--- a/compiler/rustc_ty_utils/src/ty.rs
+++ b/compiler/rustc_ty_utils/src/ty.rs
@@ -1,4 +1,4 @@
-use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
+use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_index::bit_set::BitSet;
@@ -6,7 +6,6 @@ use rustc_middle::query::Providers;
 use rustc_middle::ty::{
     self, EarlyBinder, ToPredicate, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor,
 };
-use rustc_session::config::TraitSolver;
 use rustc_span::def_id::{DefId, LocalDefId, CRATE_DEF_ID};
 use rustc_span::DUMMY_SP;
 use rustc_trait_selection::traits;
@@ -131,11 +130,6 @@ fn param_env(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
     // are any errors at that point, so outside of type inference you can be
     // sure that this will succeed without errors anyway.
 
-    if tcx.sess.opts.unstable_opts.trait_solver == TraitSolver::Chalk {
-        let environment = well_formed_types_in_env(tcx, def_id);
-        predicates.extend(environment);
-    }
-
     if tcx.def_kind(def_id) == DefKind::AssocFn
         && tcx.associated_item(def_id).container == ty::AssocItemContainer::TraitContainer
     {
@@ -319,116 +313,6 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for ImplTraitInTraitFinder<'_, 'tcx> {
     }
 }
 
-/// Elaborate the environment.
-///
-/// Collect a list of `Predicate`'s used for building the `ParamEnv`. Adds `TypeWellFormedFromEnv`'s
-/// that are assumed to be well-formed (because they come from the environment).
-///
-/// Used only in chalk mode.
-fn well_formed_types_in_env(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::List<ty::Clause<'_>> {
-    use rustc_hir::{ForeignItemKind, ImplItemKind, ItemKind, Node, TraitItemKind};
-
-    debug!("environment(def_id = {:?})", def_id);
-
-    // The environment of an impl Trait type is its defining function's environment.
-    if let Some(parent) = ty::is_impl_trait_defn(tcx, def_id) {
-        return well_formed_types_in_env(tcx, parent.to_def_id());
-    }
-
-    // Compute the bounds on `Self` and the type parameters.
-    let ty::InstantiatedPredicates { predicates, .. } =
-        tcx.predicates_of(def_id).instantiate_identity(tcx);
-
-    let clauses = predicates.into_iter();
-
-    if !def_id.is_local() {
-        return ty::List::empty();
-    }
-    let node = tcx.hir().get_by_def_id(def_id.expect_local());
-
-    enum NodeKind {
-        TraitImpl,
-        InherentImpl,
-        Fn,
-        Other,
-    }
-
-    let node_kind = match node {
-        Node::TraitItem(item) => match item.kind {
-            TraitItemKind::Fn(..) => NodeKind::Fn,
-            _ => NodeKind::Other,
-        },
-
-        Node::ImplItem(item) => match item.kind {
-            ImplItemKind::Fn(..) => NodeKind::Fn,
-            _ => NodeKind::Other,
-        },
-
-        Node::Item(item) => match item.kind {
-            ItemKind::Impl(hir::Impl { of_trait: Some(_), .. }) => NodeKind::TraitImpl,
-            ItemKind::Impl(hir::Impl { of_trait: None, .. }) => NodeKind::InherentImpl,
-            ItemKind::Fn(..) => NodeKind::Fn,
-            _ => NodeKind::Other,
-        },
-
-        Node::ForeignItem(item) => match item.kind {
-            ForeignItemKind::Fn(..) => NodeKind::Fn,
-            _ => NodeKind::Other,
-        },
-
-        // FIXME: closures?
-        _ => NodeKind::Other,
-    };
-
-    // FIXME(eddyb) isn't the unordered nature of this a hazard?
-    let mut inputs = FxIndexSet::default();
-
-    match node_kind {
-        // In a trait impl, we assume that the header trait ref and all its
-        // constituents are well-formed.
-        NodeKind::TraitImpl => {
-            let trait_ref = tcx.impl_trait_ref(def_id).expect("not an impl").subst_identity();
-
-            // FIXME(chalk): this has problems because of late-bound regions
-            //inputs.extend(trait_ref.substs.iter().flat_map(|arg| arg.walk()));
-            inputs.extend(trait_ref.substs.iter());
-        }
-
-        // In an inherent impl, we assume that the receiver type and all its
-        // constituents are well-formed.
-        NodeKind::InherentImpl => {
-            let self_ty = tcx.type_of(def_id).subst_identity();
-            inputs.extend(self_ty.walk());
-        }
-
-        // In an fn, we assume that the arguments and all their constituents are
-        // well-formed.
-        NodeKind::Fn => {
-            let fn_sig = tcx.fn_sig(def_id).subst_identity();
-            let fn_sig = tcx.liberate_late_bound_regions(def_id, fn_sig);
-
-            inputs.extend(fn_sig.inputs().iter().flat_map(|ty| ty.walk()));
-        }
-
-        NodeKind::Other => (),
-    }
-    let input_clauses = inputs.into_iter().filter_map(|arg| {
-        match arg.unpack() {
-            ty::GenericArgKind::Type(ty) => {
-                Some(ty::ClauseKind::TypeWellFormedFromEnv(ty).to_predicate(tcx))
-            }
-
-            // FIXME(eddyb) no WF conditions from lifetimes?
-            ty::GenericArgKind::Lifetime(_) => None,
-
-            // FIXME(eddyb) support const generics in Chalk
-            ty::GenericArgKind::Const(_) => None,
-        }
-    });
-
-    tcx.mk_clauses_from_iter(clauses.chain(input_clauses))
-}
-
 fn param_env_reveal_all_normalized(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
     tcx.param_env(def_id).with_reveal_all_normalized(tcx)
 }
diff --git a/src/bootstrap/flags.rs b/src/bootstrap/flags.rs
index dc05f47ee9c..a882336c3c4 100644
--- a/src/bootstrap/flags.rs
+++ b/src/bootstrap/flags.rs
@@ -304,7 +304,7 @@ pub enum Subcommand {
             ./x.py test library/std --test-args hash_map
             ./x.py test library/std --stage 0 --no-doc
             ./x.py test tests/ui --bless
-            ./x.py test tests/ui --compare-mode chalk
+            ./x.py test tests/ui --compare-mode next-solver
         Note that `test tests/* --stage N` does NOT depend on `build compiler/rustc --stage N`;
         just like `build library/std --stage N` it tests the compiler produced by the previous
         stage.
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index b2f9c0bccea..0182d50773d 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -342,8 +342,7 @@ pub(crate) fn clean_predicate<'tcx>(
         // FIXME(generic_const_exprs): should this do something?
         ty::ClauseKind::ConstEvaluatable(..)
         | ty::ClauseKind::WellFormed(..)
-        | ty::ClauseKind::ConstArgHasType(..)
-        | ty::ClauseKind::TypeWellFormedFromEnv(..) => None,
+        | ty::ClauseKind::ConstArgHasType(..) => None,
     }
 }
 
diff --git a/src/tools/compiletest/src/common.rs b/src/tools/compiletest/src/common.rs
index c95a125c737..7c17e92d0df 100644
--- a/src/tools/compiletest/src/common.rs
+++ b/src/tools/compiletest/src/common.rs
@@ -107,7 +107,6 @@ string_enum! {
     #[derive(Clone, Debug, PartialEq)]
     pub enum CompareMode {
         Polonius => "polonius",
-        Chalk => "chalk",
         NextSolver => "next-solver",
         NextSolverCoherence => "next-solver-coherence",
         SplitDwarf => "split-dwarf",
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index fddfbac78d5..e8d0ebd40b0 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -2435,9 +2435,6 @@ impl<'test> TestCx<'test> {
             Some(CompareMode::Polonius) => {
                 rustc.args(&["-Zpolonius"]);
             }
-            Some(CompareMode::Chalk) => {
-                rustc.args(&["-Ztrait-solver=chalk"]);
-            }
             Some(CompareMode::NextSolver) => {
                 rustc.args(&["-Ztrait-solver=next"]);
             }
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index e1ee11e41c3..1f6c0b75a09 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -122,10 +122,6 @@ const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     "byteorder", // via ruzstd in object in thorin-dwp
     "cc",
     "cfg-if",
-    "chalk-derive",
-    "chalk-engine",
-    "chalk-ir",
-    "chalk-solve",
     "compiler_builtins",
     "convert_case", // dependency of derive_more
     "cpufeatures",
@@ -149,7 +145,6 @@ const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     "fallible-iterator", // dependency of `thorin`
     "fastrand",
     "field-offset",
-    "fixedbitset",
     "flate2",
     "fluent-bundle",
     "fluent-langneg",
@@ -199,7 +194,6 @@ const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     "parking_lot_core",
     "pathdiff",
     "perf-event-open-sys",
-    "petgraph",
     "pin-project-lite",
     "polonius-engine",
     "ppv-lite86",
diff --git a/src/tools/tidy/src/ui_tests.rs b/src/tools/tidy/src/ui_tests.rs
index 3ed587caadc..55bf38110a6 100644
--- a/src/tools/tidy/src/ui_tests.rs
+++ b/src/tools/tidy/src/ui_tests.rs
@@ -11,7 +11,7 @@ use std::path::{Path, PathBuf};
 const ENTRY_LIMIT: usize = 900;
 // FIXME: The following limits should be reduced eventually.
 const ISSUES_ENTRY_LIMIT: usize = 1896;
-const ROOT_ENTRY_LIMIT: usize = 871;
+const ROOT_ENTRY_LIMIT: usize = 870;
 
 const EXPECTED_TEST_FILE_EXTENSIONS: &[&str] = &[
     "rs",     // test source files
diff --git a/tests/ui/chalkify/arithmetic.rs b/tests/ui/chalkify/arithmetic.rs
deleted file mode 100644
index 6c78a71b0fc..00000000000
--- a/tests/ui/chalkify/arithmetic.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-fn main() {
-    1 + 2;
-    3 * 6;
-    2 - 5;
-    17 / 6;
-    23 % 11;
-    4 & 6;
-    7 | 15;
-    4 << 7;
-    123 >> 3;
-    1 == 2;
-    5 != 5;
-    6 < 2;
-    7 > 11;
-    3 <= 1;
-    9 >= 14;
-}
diff --git a/tests/ui/chalkify/assert.rs b/tests/ui/chalkify/assert.rs
deleted file mode 100644
index 834c8935e76..00000000000
--- a/tests/ui/chalkify/assert.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-fn main() {
-    assert_eq!(1, 1);
-}
diff --git a/tests/ui/chalkify/basic.rs b/tests/ui/chalkify/basic.rs
deleted file mode 100644
index 4a7cd939669..00000000000
--- a/tests/ui/chalkify/basic.rs
+++ /dev/null
@@ -1,12 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo {}
-
-struct Bar {}
-
-impl Foo for Bar {}
-
-fn main() -> () {
-    let _ = Bar {};
-}
diff --git a/tests/ui/chalkify/bugs/async.rs b/tests/ui/chalkify/bugs/async.rs
deleted file mode 100644
index a1ef4732b63..00000000000
--- a/tests/ui/chalkify/bugs/async.rs
+++ /dev/null
@@ -1,25 +0,0 @@
-// edition:2021
-// known-bug: unknown
-// unset-rustc-env:RUST_BACKTRACE
-// compile-flags:-Z trait-solver=chalk
-// error-pattern:internal compiler error
-// failure-status:101
-// normalize-stderr-test "DefId\([^)]*\)" -> "..."
-// normalize-stderr-test "\nerror: internal compiler error.*\n\n" -> ""
-// normalize-stderr-test "note:.*unexpectedly panicked.*\n\n" -> ""
-// normalize-stderr-test "note: we would appreciate a bug report.*\n\n" -> ""
-// normalize-stderr-test "note: compiler flags.*\n\n" -> ""
-// normalize-stderr-test "note: rustc.*running on.*\n\n" -> ""
-// normalize-stderr-test "thread.*panicked.*\n" -> ""
-// normalize-stderr-test "stack backtrace:\n" -> ""
-// normalize-stderr-test "\s\d{1,}: .*\n" -> ""
-// normalize-stderr-test "\s at .*\n" -> ""
-// normalize-stderr-test ".*note: Some details.*\n" -> ""
-// normalize-stderr-test "\n\n[ ]*\n" -> ""
-// normalize-stderr-test "compiler/.*: projection" -> "projection"
-
-fn main() -> () {}
-
-async fn foo(x: u32) -> u32 {
-    x
-}
diff --git a/tests/ui/chalkify/bugs/async.stderr b/tests/ui/chalkify/bugs/async.stderr
deleted file mode 100644
index 9ebaac31dcb..00000000000
--- a/tests/ui/chalkify/bugs/async.stderr
+++ /dev/null
@@ -1,22 +0,0 @@
-error[E0277]: `[async fn body@$DIR/async.rs:23:29: 25:2]` is not a future
-  --> $DIR/async.rs:23:25
-   |
-LL | async fn foo(x: u32) -> u32 {
-   |                         ^^^ `[async fn body@$DIR/async.rs:23:29: 25:2]` is not a future
-   |
-   = help: the trait `Future` is not implemented for `[async fn body@$DIR/async.rs:23:29: 25:2]`
-   = note: [async fn body@$DIR/async.rs:23:29: 25:2] must be a future or must implement `IntoFuture` to be awaited
-
-error: internal compiler error: projection clauses should be implied from elsewhere. obligation: `Obligation(predicate=Binder { value: ProjectionPredicate(AliasTy { substs: [[async fn body@$DIR/async.rs:23:29: 25:2]], def_id: ... }, Term::Ty(u32)), bound_vars: [] }, depth=0)`
-  --> $DIR/async.rs:23:25
-   |
-LL | async fn foo(x: u32) -> u32 {
-   |                         ^^^query stack during panic:
-#0 [typeck] type-checking `foo`
-#1 [type_of] computing type of `foo::{opaque#0}`
-#2 [check_mod_item_types] checking item types in top-level module
-#3 [analysis] running analysis passes on this crate
-end of query stack
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/chalkify/builtin-copy-clone.rs b/tests/ui/chalkify/builtin-copy-clone.rs
deleted file mode 100644
index a478c006ef1..00000000000
--- a/tests/ui/chalkify/builtin-copy-clone.rs
+++ /dev/null
@@ -1,45 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-// Test that `Clone` is correctly implemented for builtin types.
-
-#[derive(Copy, Clone)]
-struct S(#[allow(unused_tuple_struct_fields)] i32);
-
-fn test_clone<T: Clone>(arg: T) {
-    let _ = arg.clone();
-}
-
-fn test_copy<T: Copy>(arg: T) {
-    let _ = arg;
-    let _ = arg;
-}
-
-fn test_copy_clone<T: Copy + Clone>(arg: T) {
-    test_copy(arg);
-    test_clone(arg);
-}
-
-fn foo() { }
-
-fn main() {
-    // FIXME: add closures when they're considered WF
-    test_copy_clone(foo);
-    let f: fn() = foo;
-    test_copy_clone(f);
-    // FIXME(#86252): reinstate array test after chalk upgrade
-    //test_copy_clone([1; 56]);
-    test_copy_clone((1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1));
-    test_copy_clone((1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, true, 'a', 1.1));
-    test_copy_clone(());
-    test_copy_clone(((1, 1), (1, 1, 1), (1.1, 1, 1, 'a'), ()));
-
-    let a = (
-        (S(1), S(0)),
-        (
-            (S(0), S(0), S(1)),
-            S(0)
-        )
-    );
-    test_copy_clone(a);
-}
diff --git a/tests/ui/chalkify/chalk_initial_program.rs b/tests/ui/chalkify/chalk_initial_program.rs
deleted file mode 100644
index 21de72b6fcc..00000000000
--- a/tests/ui/chalkify/chalk_initial_program.rs
+++ /dev/null
@@ -1,16 +0,0 @@
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-
-impl Foo for i32 { }
-
-impl Foo for u32 { }
-
-fn gimme<F: Foo>() { }
-
-// Note: this also tests that `std::process::Termination` is implemented for `()`.
-fn main() {
-    gimme::<i32>();
-    gimme::<u32>();
-    gimme::<f32>(); //~ERROR the trait bound `f32: Foo` is not satisfied
-}
diff --git a/tests/ui/chalkify/chalk_initial_program.stderr b/tests/ui/chalkify/chalk_initial_program.stderr
deleted file mode 100644
index 343c0a31862..00000000000
--- a/tests/ui/chalkify/chalk_initial_program.stderr
+++ /dev/null
@@ -1,18 +0,0 @@
-error[E0277]: the trait bound `f32: Foo` is not satisfied
-  --> $DIR/chalk_initial_program.rs:15:13
-   |
-LL |     gimme::<f32>();
-   |             ^^^ the trait `Foo` is not implemented for `f32`
-   |
-   = help: the following other types implement trait `Foo`:
-             i32
-             u32
-note: required by a bound in `gimme`
-  --> $DIR/chalk_initial_program.rs:9:13
-   |
-LL | fn gimme<F: Foo>() { }
-   |             ^^^ required by this bound in `gimme`
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/chalkify/closure.rs b/tests/ui/chalkify/closure.rs
deleted file mode 100644
index a908a1e97ec..00000000000
--- a/tests/ui/chalkify/closure.rs
+++ /dev/null
@@ -1,38 +0,0 @@
-// compile-flags: -Z trait-solver=chalk
-
-fn main() -> () {
-    let t = || {};
-    t();
-
-    let mut a = 0;
-    let mut b = move || {
-        a = 1;
-    };
-    b();
-
-    let mut c = b;
-
-    c();
-    b();
-
-    let mut a = 0;
-    let mut b = || {
-        a = 1;
-    };
-    b();
-
-    let mut c = b;
-
-    c();
-    b(); //~ ERROR
-
-    // FIXME(chalk): this doesn't quite work
-    /*
-    let b = |c| {
-        c
-    };
-
-    let a = &32;
-    b(a);
-    */
-}
diff --git a/tests/ui/chalkify/closure.stderr b/tests/ui/chalkify/closure.stderr
deleted file mode 100644
index a33c0ba0d37..00000000000
--- a/tests/ui/chalkify/closure.stderr
+++ /dev/null
@@ -1,22 +0,0 @@
-error[E0382]: borrow of moved value: `b`
-  --> $DIR/closure.rs:27:5
-   |
-LL |     let mut c = b;
-   |                 - value moved here
-...
-LL |     b();
-   |     ^ value borrowed here after move
-   |
-note: closure cannot be moved more than once as it is not `Copy` due to moving the variable `a` out of its environment
-  --> $DIR/closure.rs:20:9
-   |
-LL |         a = 1;
-   |         ^
-help: consider mutably borrowing `b`
-   |
-LL |     let mut c = &mut b;
-   |                 ++++
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0382`.
diff --git a/tests/ui/chalkify/generic_impls.rs b/tests/ui/chalkify/generic_impls.rs
deleted file mode 100644
index 7d33e12d8be..00000000000
--- a/tests/ui/chalkify/generic_impls.rs
+++ /dev/null
@@ -1,18 +0,0 @@
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-
-impl<T> Foo for (T, u32) { }
-
-fn gimme<F: Foo>() { }
-
-fn foo<T>() {
-    gimme::<(T, u32)>();
-    gimme::<(Option<T>, u32)>();
-    gimme::<(Option<T>, f32)>(); //~ ERROR
-}
-
-fn main() {
-    gimme::<(i32, u32)>();
-    gimme::<(i32, f32)>(); //~ ERROR
-}
diff --git a/tests/ui/chalkify/generic_impls.stderr b/tests/ui/chalkify/generic_impls.stderr
deleted file mode 100644
index d4a8354d3fc..00000000000
--- a/tests/ui/chalkify/generic_impls.stderr
+++ /dev/null
@@ -1,29 +0,0 @@
-error[E0277]: the trait bound `(Option<T>, f32): Foo` is not satisfied
-  --> $DIR/generic_impls.rs:12:13
-   |
-LL |     gimme::<(Option<T>, f32)>();
-   |             ^^^^^^^^^^^^^^^^ the trait `Foo` is not implemented for `(Option<T>, f32)`
-   |
-   = help: the trait `Foo` is implemented for `(T, u32)`
-note: required by a bound in `gimme`
-  --> $DIR/generic_impls.rs:7:13
-   |
-LL | fn gimme<F: Foo>() { }
-   |             ^^^ required by this bound in `gimme`
-
-error[E0277]: the trait bound `(i32, f32): Foo` is not satisfied
-  --> $DIR/generic_impls.rs:17:13
-   |
-LL |     gimme::<(i32, f32)>();
-   |             ^^^^^^^^^^ the trait `Foo` is not implemented for `(i32, f32)`
-   |
-   = help: the trait `Foo` is implemented for `(T, u32)`
-note: required by a bound in `gimme`
-  --> $DIR/generic_impls.rs:7:13
-   |
-LL | fn gimme<F: Foo>() { }
-   |             ^^^ required by this bound in `gimme`
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/chalkify/impl_wf.rs b/tests/ui/chalkify/impl_wf.rs
deleted file mode 100644
index c8dfd4c3a5b..00000000000
--- a/tests/ui/chalkify/impl_wf.rs
+++ /dev/null
@@ -1,26 +0,0 @@
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo: Sized { }
-
-trait Bar {
-    type Item: Foo;
-}
-
-impl Foo for i32 { }
-
-impl Foo for str { }
-//~^ ERROR the size for values of type `str` cannot be known at compilation time
-
-
-// Implicit `T: Sized` bound.
-impl<T> Foo for Option<T> { }
-
-trait Baz<U: ?Sized> where U: Foo { }
-
-impl Baz<i32> for i32 { }
-
-impl Baz<f32> for f32 { }
-//~^ ERROR the trait bound `f32: Foo` is not satisfied
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/impl_wf.stderr b/tests/ui/chalkify/impl_wf.stderr
deleted file mode 100644
index 84c32fa3771..00000000000
--- a/tests/ui/chalkify/impl_wf.stderr
+++ /dev/null
@@ -1,29 +0,0 @@
-error[E0277]: the size for values of type `str` cannot be known at compilation time
-  --> $DIR/impl_wf.rs:11:14
-   |
-LL | impl Foo for str { }
-   |              ^^^ doesn't have a size known at compile-time
-   |
-   = help: the trait `Sized` is not implemented for `str`
-note: required by a bound in `Foo`
-  --> $DIR/impl_wf.rs:3:12
-   |
-LL | trait Foo: Sized { }
-   |            ^^^^^ required by this bound in `Foo`
-
-error[E0277]: the trait bound `f32: Foo` is not satisfied
-  --> $DIR/impl_wf.rs:22:19
-   |
-LL | impl Baz<f32> for f32 { }
-   |                   ^^^ the trait `Foo` is not implemented for `f32`
-   |
-   = help: the trait `Foo` is implemented for `i32`
-note: required by a bound in `Baz`
-  --> $DIR/impl_wf.rs:18:31
-   |
-LL | trait Baz<U: ?Sized> where U: Foo { }
-   |                               ^^^ required by this bound in `Baz`
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/chalkify/impl_wf_2.rs b/tests/ui/chalkify/impl_wf_2.rs
deleted file mode 100644
index 325044ad634..00000000000
--- a/tests/ui/chalkify/impl_wf_2.rs
+++ /dev/null
@@ -1,33 +0,0 @@
-// Split out of impl_wf.rs to work around rust aborting compilation early
-
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo: Sized { }
-
-trait Bar {
-    type Item: Foo;
-}
-
-impl Foo for i32 { }
-
-// Implicit `T: Sized` bound.
-impl<T> Foo for Option<T> { }
-
-impl Bar for () {
-    type Item = i32;
-}
-
-impl<T> Bar for Option<T> {
-    type Item = Option<T>;
-}
-
-impl Bar for f32 {
-    type Item = f32;
-    //~^ ERROR the trait bound `f32: Foo` is not satisfied
-}
-
-trait Baz<U: ?Sized> where U: Foo { }
-
-impl Baz<i32> for i32 { }
-
-fn main() {}
diff --git a/tests/ui/chalkify/impl_wf_2.stderr b/tests/ui/chalkify/impl_wf_2.stderr
deleted file mode 100644
index 1c1df644b06..00000000000
--- a/tests/ui/chalkify/impl_wf_2.stderr
+++ /dev/null
@@ -1,16 +0,0 @@
-error[E0277]: the trait bound `f32: Foo` is not satisfied
-  --> $DIR/impl_wf_2.rs:25:17
-   |
-LL |     type Item = f32;
-   |                 ^^^ the trait `Foo` is not implemented for `f32`
-   |
-   = help: the trait `Foo` is implemented for `i32`
-note: required by a bound in `Bar::Item`
-  --> $DIR/impl_wf_2.rs:8:16
-   |
-LL |     type Item: Foo;
-   |                ^^^ required by this bound in `Bar::Item`
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/chalkify/inherent_impl.rs b/tests/ui/chalkify/inherent_impl.rs
deleted file mode 100644
index f0f24d485cd..00000000000
--- a/tests/ui/chalkify/inherent_impl.rs
+++ /dev/null
@@ -1,42 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-
-impl Foo for i32 { }
-
-struct S<T: Foo> {
-    x: T,
-}
-
-fn only_foo<T: Foo>(_x: &T) { }
-
-impl<T> S<T> {
-    // Test that we have the correct environment inside an inherent method.
-    fn dummy_foo(&self) {
-        only_foo(&self.x)
-    }
-}
-
-trait Bar { }
-impl Bar for u32 { }
-
-fn only_bar<T: Bar>() { }
-
-impl<T> S<T> {
-    // Test that the environment of `dummy_bar` adds up with the environment
-    // of the inherent impl.
-    fn dummy_bar<U: Bar>(&self) {
-        only_foo(&self.x);
-        only_bar::<U>();
-    }
-}
-
-fn main() {
-    let s = S {
-        x: 5,
-    };
-
-    s.dummy_bar::<u32>();
-    s.dummy_foo();
-}
diff --git a/tests/ui/chalkify/inherent_impl_min.rs b/tests/ui/chalkify/inherent_impl_min.rs
deleted file mode 100644
index 3eda7102dec..00000000000
--- a/tests/ui/chalkify/inherent_impl_min.rs
+++ /dev/null
@@ -1,27 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-
-impl Foo for i32 { }
-
-struct S<T: Foo> {
-    x: T,
-}
-
-fn only_foo<T: Foo>(_x: &T) { }
-
-impl<T> S<T> {
-    // Test that we have the correct environment inside an inherent method.
-    fn dummy_foo(&self) {
-        only_foo(&self.x)
-    }
-}
-
-fn main() {
-    let s = S {
-        x: 5,
-    };
-
-    s.dummy_foo();
-}
diff --git a/tests/ui/chalkify/lower_env1.rs b/tests/ui/chalkify/lower_env1.rs
deleted file mode 100644
index c8762001e6a..00000000000
--- a/tests/ui/chalkify/lower_env1.rs
+++ /dev/null
@@ -1,14 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-#![allow(dead_code)]
-
-trait Foo { }
-
-trait Bar where Self: Foo { }
-
-fn bar<T: Bar + ?Sized>() {
-}
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/lower_env2.rs b/tests/ui/chalkify/lower_env2.rs
deleted file mode 100644
index 7d4f81f12ea..00000000000
--- a/tests/ui/chalkify/lower_env2.rs
+++ /dev/null
@@ -1,16 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-#![allow(dead_code)]
-
-trait Foo { }
-
-struct S<'a, T: ?Sized> where T: Foo {
-    data: &'a T,
-}
-
-fn bar<T: Foo>(_x: S<'_, T>) { // note that we have an implicit `T: Sized` bound
-}
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/lower_env3.rs b/tests/ui/chalkify/lower_env3.rs
deleted file mode 100644
index 5b70c4abbb5..00000000000
--- a/tests/ui/chalkify/lower_env3.rs
+++ /dev/null
@@ -1,16 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-#![allow(dead_code)]
-
-trait Foo {
-    fn foo(&self);
-}
-
-impl<T> Foo for T where T: Clone {
-    fn foo(&self) {
-    }
-}
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/lower_impl.rs b/tests/ui/chalkify/lower_impl.rs
deleted file mode 100644
index 6f79b3ba386..00000000000
--- a/tests/ui/chalkify/lower_impl.rs
+++ /dev/null
@@ -1,17 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-
-impl<T: 'static> Foo for T where T: Iterator<Item = i32> { }
-
-trait Bar {
-    type Assoc;
-}
-
-impl<T> Bar for T where T: Iterator<Item = i32> {
-    type Assoc = Vec<T>;
-}
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/lower_struct.rs b/tests/ui/chalkify/lower_struct.rs
deleted file mode 100644
index 6be0d4dd5bd..00000000000
--- a/tests/ui/chalkify/lower_struct.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-struct Foo<'a, T> where Box<T>: Clone {
-    _x: std::marker::PhantomData<&'a T>,
-}
-
-fn main() { }
diff --git a/tests/ui/chalkify/lower_trait.rs b/tests/ui/chalkify/lower_trait.rs
deleted file mode 100644
index 8f5b358220b..00000000000
--- a/tests/ui/chalkify/lower_trait.rs
+++ /dev/null
@@ -1,11 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Bar { }
-
-trait Foo<S, T: ?Sized> {
-    type Assoc: Bar + ?Sized;
-}
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/lower_trait_higher_rank.rs b/tests/ui/chalkify/lower_trait_higher_rank.rs
deleted file mode 100644
index f04a1deea87..00000000000
--- a/tests/ui/chalkify/lower_trait_higher_rank.rs
+++ /dev/null
@@ -1,9 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo<F: ?Sized> where for<'a> F: Fn(&'a (u8, u16)) -> &'a u8
-{
-}
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/lower_trait_where_clause.rs b/tests/ui/chalkify/lower_trait_where_clause.rs
deleted file mode 100644
index a21d2f31963..00000000000
--- a/tests/ui/chalkify/lower_trait_where_clause.rs
+++ /dev/null
@@ -1,16 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-use std::borrow::Borrow;
-
-trait Foo<'a, 'b, T, U>
-where
-    T: Borrow<U> + ?Sized,
-    U: ?Sized + 'b,
-    'a: 'b,
-    Box<T>:, // NOTE(#53696) this checks an empty list of bounds.
-{
-}
-
-fn main() {
-}
diff --git a/tests/ui/chalkify/println.rs b/tests/ui/chalkify/println.rs
deleted file mode 100644
index edddc382152..00000000000
--- a/tests/ui/chalkify/println.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-fn main() {
-    println!("hello");
-}
diff --git a/tests/ui/chalkify/projection.rs b/tests/ui/chalkify/projection.rs
deleted file mode 100644
index 19bb2ae1497..00000000000
--- a/tests/ui/chalkify/projection.rs
+++ /dev/null
@@ -1,25 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-
-trait Bar {
-    type Item: Foo;
-}
-
-impl Foo for i32 { }
-impl Bar for i32 {
-    type Item = i32;
-}
-
-fn only_foo<T: Foo>() { }
-
-fn only_bar<T: Bar>() {
-    // `T` implements `Bar` hence `<T as Bar>::Item` must also implement `Bar`
-    only_foo::<T::Item>()
-}
-
-fn main() {
-    only_bar::<i32>();
-    only_foo::<<i32 as Bar>::Item>();
-}
diff --git a/tests/ui/chalkify/recursive_where_clause_on_type.rs b/tests/ui/chalkify/recursive_where_clause_on_type.rs
deleted file mode 100644
index c2c8aa6aabe..00000000000
--- a/tests/ui/chalkify/recursive_where_clause_on_type.rs
+++ /dev/null
@@ -1,30 +0,0 @@
-// FIXME(chalk): should fail, see comments
-// check-fail
-// compile-flags: -Z trait-solver=chalk
-
-#![feature(trivial_bounds)]
-
-trait Bar {
-    fn foo();
-}
-trait Foo: Bar { }
-
-struct S where S: Foo;
-
-impl Foo for S {
-}
-
-fn bar<T: Bar>() {
-    T::foo();
-}
-
-fn foo<T: Foo>() {
-    bar::<T>()
-}
-
-fn main() {
-    // For some reason, the error is duplicated...
-
-    foo::<S>() //~ ERROR the type `S` is not well-formed
-    //~^ ERROR the type `S` is not well-formed
-}
diff --git a/tests/ui/chalkify/recursive_where_clause_on_type.stderr b/tests/ui/chalkify/recursive_where_clause_on_type.stderr
deleted file mode 100644
index cead5adeaaa..00000000000
--- a/tests/ui/chalkify/recursive_where_clause_on_type.stderr
+++ /dev/null
@@ -1,14 +0,0 @@
-error: the type `S` is not well-formed
-  --> $DIR/recursive_where_clause_on_type.rs:28:11
-   |
-LL |     foo::<S>()
-   |           ^
-
-error: the type `S` is not well-formed
-  --> $DIR/recursive_where_clause_on_type.rs:28:5
-   |
-LL |     foo::<S>()
-   |     ^^^^^^^^
-
-error: aborting due to 2 previous errors
-
diff --git a/tests/ui/chalkify/super_trait.rs b/tests/ui/chalkify/super_trait.rs
deleted file mode 100644
index 540ae51e57f..00000000000
--- a/tests/ui/chalkify/super_trait.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-trait Bar: Foo { }
-
-impl Foo for i32 { }
-impl Bar for i32 { }
-
-fn only_foo<T: Foo>() { }
-
-fn only_bar<T: Bar>() {
-    // `T` implements `Bar` hence `T` must also implement `Foo`
-    only_foo::<T>()
-}
-
-fn main() {
-    only_bar::<i32>()
-}
diff --git a/tests/ui/chalkify/trait-objects.rs b/tests/ui/chalkify/trait-objects.rs
deleted file mode 100644
index 144d9788b82..00000000000
--- a/tests/ui/chalkify/trait-objects.rs
+++ /dev/null
@@ -1,12 +0,0 @@
-// check-pass
-// compile-flags: -Z trait-solver=chalk
-
-use std::fmt::Display;
-
-fn main() {
-    let d: &dyn Display = &mut 3;
-    d.to_string();
-    (&d).to_string();
-    let f: &dyn Fn(i32) -> _ = &|x| x + x;
-    f(2);
-}
diff --git a/tests/ui/chalkify/trait_implied_bound.rs b/tests/ui/chalkify/trait_implied_bound.rs
deleted file mode 100644
index f97dbf6b7e7..00000000000
--- a/tests/ui/chalkify/trait_implied_bound.rs
+++ /dev/null
@@ -1,18 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-trait Bar<U> where U: Foo { }
-
-impl Foo for i32 { }
-impl Bar<i32> for i32 { }
-
-fn only_foo<T: Foo>() { }
-
-fn only_bar<U, T: Bar<U>>() {
-    only_foo::<U>()
-}
-
-fn main() {
-    only_bar::<i32, i32>()
-}
diff --git a/tests/ui/chalkify/type_implied_bound.rs b/tests/ui/chalkify/type_implied_bound.rs
deleted file mode 100644
index 70f1b4265e4..00000000000
--- a/tests/ui/chalkify/type_implied_bound.rs
+++ /dev/null
@@ -1,29 +0,0 @@
-// run-pass
-// compile-flags: -Z trait-solver=chalk
-
-trait Eq { }
-trait Hash: Eq { }
-
-impl Eq for i32 { }
-impl Hash for i32 { }
-
-struct Set<T: Hash> {
-    _x: T,
-}
-
-fn only_eq<T: Eq>() { }
-
-fn take_a_set<T>(_: &Set<T>) {
-    // `Set<T>` is an input type of `take_a_set`, hence we know that
-    // `T` must implement `Hash`, and we know in turn that `T` must
-    // implement `Eq`.
-    only_eq::<T>()
-}
-
-fn main() {
-    let set = Set {
-        _x: 5,
-    };
-
-    take_a_set(&set);
-}
diff --git a/tests/ui/chalkify/type_inference.rs b/tests/ui/chalkify/type_inference.rs
deleted file mode 100644
index d7167d0dc57..00000000000
--- a/tests/ui/chalkify/type_inference.rs
+++ /dev/null
@@ -1,28 +0,0 @@
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-impl Foo for i32 { }
-
-trait Bar { }
-impl Bar for i32 { }
-impl Bar for u32 { }
-
-fn only_foo<T: Foo>(_x: T) { }
-
-fn only_bar<T: Bar>(_x: T) { }
-
-fn main() {
-    let x = 5.0;
-
-    // The only type which implements `Foo` is `i32`, so the chalk trait solver
-    // is expecting a variable of type `i32`. This behavior differs from the
-    // old-style trait solver. I guess this will change, that's why I'm
-    // adding that test.
-    // FIXME(chalk): order of these two errors is non-deterministic,
-    // so let's just hide one for now
-    //only_foo(x); // ERROR the trait bound `f64: Foo` is not satisfied
-
-    // Here we have two solutions so we get back the behavior of the old-style
-    // trait solver.
-    only_bar(x); //~ ERROR the trait bound `{float}: Bar` is not satisfied
-}
diff --git a/tests/ui/chalkify/type_inference.stderr b/tests/ui/chalkify/type_inference.stderr
deleted file mode 100644
index 508a6dd1388..00000000000
--- a/tests/ui/chalkify/type_inference.stderr
+++ /dev/null
@@ -1,20 +0,0 @@
-error[E0277]: the trait bound `{float}: Bar` is not satisfied
-  --> $DIR/type_inference.rs:27:14
-   |
-LL |     only_bar(x);
-   |     -------- ^ the trait `Bar` is not implemented for `{float}`
-   |     |
-   |     required by a bound introduced by this call
-   |
-   = help: the following other types implement trait `Bar`:
-             i32
-             u32
-note: required by a bound in `only_bar`
-  --> $DIR/type_inference.rs:12:16
-   |
-LL | fn only_bar<T: Bar>(_x: T) { }
-   |                ^^^ required by this bound in `only_bar`
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/chalkify/type_wf.rs b/tests/ui/chalkify/type_wf.rs
deleted file mode 100644
index 37d2f5ca832..00000000000
--- a/tests/ui/chalkify/type_wf.rs
+++ /dev/null
@@ -1,25 +0,0 @@
-// check-fail
-// compile-flags: -Z trait-solver=chalk
-
-trait Foo { }
-
-struct S<T: Foo> {
-    x: T,
-}
-
-impl Foo for i32 { }
-impl<T> Foo for Option<T> { }
-
-fn main() {
-    let s = S {
-       x: 5,
-    };
-
-    let s = S {
-        x: 5.0, //~ ERROR the trait bound `{float}: Foo` is not satisfied
-    };
-
-    let s = S {
-        x: Some(5.0),
-    };
-}
diff --git a/tests/ui/chalkify/type_wf.stderr b/tests/ui/chalkify/type_wf.stderr
deleted file mode 100644
index 6e8daf63517..00000000000
--- a/tests/ui/chalkify/type_wf.stderr
+++ /dev/null
@@ -1,16 +0,0 @@
-error[E0277]: the trait bound `{float}: Foo` is not satisfied
-  --> $DIR/type_wf.rs:19:12
-   |
-LL |         x: 5.0,
-   |            ^^^ the trait `Foo` is not implemented for `{float}`
-   |
-   = help: the trait `Foo` is implemented for `i32`
-note: required by a bound in `S`
-  --> $DIR/type_wf.rs:6:13
-   |
-LL | struct S<T: Foo> {
-   |             ^^^ required by this bound in `S`
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/feature-gates/feature-gate-type_alias_impl_trait.rs b/tests/ui/feature-gates/feature-gate-type_alias_impl_trait.rs
index 6dfd7f6840f..0d019b1f502 100644
--- a/tests/ui/feature-gates/feature-gate-type_alias_impl_trait.rs
+++ b/tests/ui/feature-gates/feature-gate-type_alias_impl_trait.rs
@@ -1,4 +1,3 @@
-// ignore-compare-mode-chalk
 // check-pass
 #![feature(type_alias_impl_trait)]
 use std::fmt::Debug;
diff --git a/tests/ui/impl-trait/issue-55872-3.rs b/tests/ui/impl-trait/issue-55872-3.rs
index d031271ac08..7490a130800 100644
--- a/tests/ui/impl-trait/issue-55872-3.rs
+++ b/tests/ui/impl-trait/issue-55872-3.rs
@@ -1,5 +1,4 @@
 // edition:2018
-// ignore-compare-mode-chalk
 
 #![feature(impl_trait_in_assoc_type)]
 
diff --git a/tests/ui/impl-trait/issue-55872-3.stderr b/tests/ui/impl-trait/issue-55872-3.stderr
index c6e10f0f350..82798897433 100644
--- a/tests/ui/impl-trait/issue-55872-3.stderr
+++ b/tests/ui/impl-trait/issue-55872-3.stderr
@@ -1,8 +1,8 @@
-error[E0277]: the trait bound `[async block@$DIR/issue-55872-3.rs:16:9: 16:17]: Copy` is not satisfied
-  --> $DIR/issue-55872-3.rs:14:20
+error[E0277]: the trait bound `[async block@$DIR/issue-55872-3.rs:15:9: 15:17]: Copy` is not satisfied
+  --> $DIR/issue-55872-3.rs:13:20
    |
 LL |     fn foo<T>() -> Self::E {
-   |                    ^^^^^^^ the trait `Copy` is not implemented for `[async block@$DIR/issue-55872-3.rs:16:9: 16:17]`
+   |                    ^^^^^^^ the trait `Copy` is not implemented for `[async block@$DIR/issue-55872-3.rs:15:9: 15:17]`
 
 error: aborting due to previous error
 
diff --git a/tests/ui/impl-trait/issues/issue-65581.rs b/tests/ui/impl-trait/issues/issue-65581.rs
index b947fc1d239..af65b79d3e8 100644
--- a/tests/ui/impl-trait/issues/issue-65581.rs
+++ b/tests/ui/impl-trait/issues/issue-65581.rs
@@ -1,5 +1,4 @@
 // check-pass
-// ignore-compare-mode-chalk
 
 #![allow(dead_code)]