6 files changed, 71 insertions, 86 deletions
diff --git a/Cargo.lock b/Cargo.lock
index 6f3d1f564..1159d0f1d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -112,9 +112,17 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
 [[package]]
+name = "chalk-base"
+version = "0.10.1-dev"
+source = "git+https://github.com/rust-lang/chalk.git?rev=5a3b871ca17529ab5aa5787594fabad1634936cb#5a3b871ca17529ab5aa5787594fabad1634936cb"
+dependencies = [
+ "lazy_static",
+]
+[[package]]
 name = "chalk-derive"
 version = "0.10.1-dev"
-source = "git+https://github.com/rust-lang/chalk.git?rev=eaab84b394007d1bed15f5470409a6ea02900a96#eaab84b394007d1bed15f5470409a6ea02900a96"
+source = "git+https://github.com/rust-lang/chalk.git?rev=5a3b871ca17529ab5aa5787594fabad1634936cb#5a3b871ca17529ab5aa5787594fabad1634936cb"
 dependencies = [
 "proc-macro2",
 "quote",
@@ -125,51 +133,32 @@ dependencies = [
 [[package]]
 name = "chalk-engine"
 version = "0.10.1-dev"
-source = "git+https://github.com/rust-lang/chalk.git?rev=eaab84b394007d1bed15f5470409a6ea02900a96#eaab84b394007d1bed15f5470409a6ea02900a96"
+source = "git+https://github.com/rust-lang/chalk.git?rev=5a3b871ca17529ab5aa5787594fabad1634936cb#5a3b871ca17529ab5aa5787594fabad1634936cb"
 dependencies = [
- "chalk-macros",
+ "chalk-base",
+ "chalk-derive",
+ "chalk-ir",
 "rustc-hash",
 ]
 [[package]]
 name = "chalk-ir"
 version = "0.10.1-dev"
-source = "git+https://github.com/rust-lang/chalk.git?rev=eaab84b394007d1bed15f5470409a6ea02900a96#eaab84b394007d1bed15f5470409a6ea02900a96"
+source = "git+https://github.com/rust-lang/chalk.git?rev=5a3b871ca17529ab5aa5787594fabad1634936cb#5a3b871ca17529ab5aa5787594fabad1634936cb"
 dependencies = [
+ "chalk-base",
 "chalk-derive",
- "chalk-engine",
- "chalk-macros",
-]
-[[package]]
-name = "chalk-macros"
-version = "0.10.1-dev"
-source = "git+https://github.com/rust-lang/chalk.git?rev=eaab84b394007d1bed15f5470409a6ea02900a96#eaab84b394007d1bed15f5470409a6ea02900a96"
-dependencies = [
- "lazy_static",
-]
-[[package]]
-name = "chalk-rust-ir"
-version = "0.10.1-dev"
-source = "git+https://github.com/rust-lang/chalk.git?rev=eaab84b394007d1bed15f5470409a6ea02900a96#eaab84b394007d1bed15f5470409a6ea02900a96"
-dependencies = [
- "chalk-derive",
- "chalk-engine",
- "chalk-ir",
- "chalk-macros",
 ]
 [[package]]
 name = "chalk-solve"
 version = "0.10.1-dev"
-source = "git+https://github.com/rust-lang/chalk.git?rev=eaab84b394007d1bed15f5470409a6ea02900a96#eaab84b394007d1bed15f5470409a6ea02900a96"
+source = "git+https://github.com/rust-lang/chalk.git?rev=5a3b871ca17529ab5aa5787594fabad1634936cb#5a3b871ca17529ab5aa5787594fabad1634936cb"
 dependencies = [
+ "chalk-base",
 "chalk-derive",
 "chalk-engine",
 "chalk-ir",
- "chalk-macros",
- "chalk-rust-ir",
 "ena",
 "itertools",
 "petgraph",
@@ -1036,7 +1025,6 @@ version = "0.1.0"
 dependencies = [
 "arrayvec",
 "chalk-ir",
- "chalk-rust-ir",
 "chalk-solve",
 "ena",
 "insta",
diff --git a/Cargo.toml b/Cargo.toml
index c034e2424..5278b5a16 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,8 +22,6 @@ opt-level = 0
 opt-level = 0
 [profile.release.package.chalk-derive]
 opt-level = 0
-[profile.release.package.chalk-macros]
-opt-level = 0
 [profile.release.package.salsa-macros]
 opt-level = 0
 [profile.release.package.xtask]
diff --git a/crates/ra_hir_ty/Cargo.toml b/crates/ra_hir_ty/Cargo.toml
index b2de7fa34..6afed58a1 100644
--- a/crates/ra_hir_ty/Cargo.toml
+++ b/crates/ra_hir_ty/Cargo.toml
@@ -27,9 +27,8 @@ test_utils = { path = "../test_utils" }
 scoped-tls = "1"
-chalk-solve =   { git = "https://github.com/rust-lang/chalk.git", rev = "eaab84b394007d1bed15f5470409a6ea02900a96" }
+chalk-solve =   { git = "https://github.com/rust-lang/chalk.git", rev = "5a3b871ca17529ab5aa5787594fabad1634936cb" }
-chalk-rust-ir = { git = "https://github.com/rust-lang/chalk.git", rev = "eaab84b394007d1bed15f5470409a6ea02900a96" }
+chalk-ir =      { git = "https://github.com/rust-lang/chalk.git", rev = "5a3b871ca17529ab5aa5787594fabad1634936cb" }
-chalk-ir =      { git = "https://github.com/rust-lang/chalk.git", rev = "eaab84b394007d1bed15f5470409a6ea02900a96" }
 [dev-dependencies]
 insta = "0.16.0"
diff --git a/crates/ra_hir_ty/src/traits/chalk.rs b/crates/ra_hir_ty/src/traits/chalk.rs
index 5b0f12a3c..61de3cc30 100644
--- a/crates/ra_hir_ty/src/traits/chalk.rs
+++ b/crates/ra_hir_ty/src/traits/chalk.rs
@@ -4,6 +4,7 @@ use std::sync::Arc;
 use log::debug;
 use chalk_ir::{fold::shift::Shift, GenericArg, TypeName};
+use chalk_solve::rust_ir::{self, WellKnownTrait};
 use hir_def::{
    lang_item::{lang_attr, LangItemTarget},
@@ -16,7 +17,6 @@ use crate::{
    db::HirDatabase, display::HirDisplay, method_resolution::TyFingerprint, utils::generics,
    CallableDef, DebruijnIndex, GenericPredicate, Substs, Ty, TypeCtor,
 };
-use chalk_rust_ir::WellKnownTrait;
 use mapping::{convert_where_clauses, generic_predicate_to_inline_bound, make_binders};
 pub use self::interner::*;
@@ -55,7 +55,7 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
    fn fn_def_datum(
        &self,
        fn_def_id: chalk_ir::FnDefId<Interner>,
-    ) -> Arc<chalk_rust_ir::FnDefDatum<Interner>> {
+    ) -> Arc<rust_ir::FnDefDatum<Interner>> {
        self.db.fn_def_datum(self.krate, fn_def_id)
    }
@@ -112,7 +112,7 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
    }
    fn well_known_trait_id(
        &self,
-        well_known_trait: chalk_rust_ir::WellKnownTrait,
+        well_known_trait: rust_ir::WellKnownTrait,
    ) -> Option<chalk_ir::TraitId<Interner>> {
        let lang_attr = lang_attr_from_well_known_trait(well_known_trait);
        let lang_items = self.db.crate_lang_items(self.krate);
@@ -133,13 +133,13 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
    fn opaque_ty_data(
        &self,
        _id: chalk_ir::OpaqueTyId<Interner>,
-    ) -> Arc<chalk_rust_ir::OpaqueTyDatum<Interner>> {
+    ) -> Arc<rust_ir::OpaqueTyDatum<Interner>> {
        unimplemented!()
    }
    fn force_impl_for(
        &self,
-        _well_known: chalk_rust_ir::WellKnownTrait,
+        _well_known: rust_ir::WellKnownTrait,
        _ty: &chalk_ir::TyData<Interner>,
    ) -> Option<bool> {
        // this method is mostly for rustc
@@ -150,6 +150,10 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
        // FIXME: implement actual object safety
        true
    }
+    fn hidden_opaque_type(&self, _id: chalk_ir::OpaqueTyId<Interner>) -> chalk_ir::Ty<Interner> {
+        Ty::Unknown.to_chalk(self.db)
+    }
 }
 pub(crate) fn program_clauses_for_chalk_env_query(
@@ -188,7 +192,7 @@ pub(crate) fn associated_ty_data_query(
        .collect();
    let where_clauses = convert_where_clauses(db, type_alias.into(), &bound_vars);
-    let bound_data = chalk_rust_ir::AssociatedTyDatumBound { bounds, where_clauses };
+    let bound_data = rust_ir::AssociatedTyDatumBound { bounds, where_clauses };
    let datum = AssociatedTyDatum {
        trait_id: trait_.to_chalk(db),
        id,
@@ -209,7 +213,7 @@ pub(crate) fn trait_datum_query(
    debug!("trait {:?} = {:?}", trait_id, trait_data.name);
    let generic_params = generics(db.upcast(), trait_.into());
    let bound_vars = Substs::bound_vars(&generic_params, DebruijnIndex::INNERMOST);
-    let flags = chalk_rust_ir::TraitFlags {
+    let flags = rust_ir::TraitFlags {
        auto: trait_data.auto,
        upstream: trait_.lookup(db.upcast()).container.module(db.upcast()).krate != krate,
        non_enumerable: true,
@@ -221,7 +225,7 @@ pub(crate) fn trait_datum_query(
    let where_clauses = convert_where_clauses(db, trait_.into(), &bound_vars);
    let associated_ty_ids =
        trait_data.associated_types().map(|type_alias| type_alias.to_chalk(db)).collect();
-    let trait_datum_bound = chalk_rust_ir::TraitDatumBound { where_clauses };
+    let trait_datum_bound = rust_ir::TraitDatumBound { where_clauses };
    let well_known =
        lang_attr(db.upcast(), trait_).and_then(|name| well_known_trait_from_lang_attr(&name));
    let trait_datum = TraitDatum {
@@ -271,12 +275,12 @@ pub(crate) fn struct_datum_query(
            convert_where_clauses(db, generic_def, &bound_vars)
        })
        .unwrap_or_else(Vec::new);
-    let flags = chalk_rust_ir::AdtFlags {
+    let flags = rust_ir::AdtFlags {
        upstream,
        // FIXME set fundamental flag correctly
        fundamental: false,
    };
-    let struct_datum_bound = chalk_rust_ir::AdtDatumBound {
+    let struct_datum_bound = rust_ir::AdtDatumBound {
        fields: Vec::new(), // FIXME add fields (only relevant for auto traits)
        where_clauses,
    };
@@ -316,9 +320,9 @@ fn impl_def_datum(
    let bound_vars = Substs::bound_vars(&generic_params, DebruijnIndex::INNERMOST);
    let trait_ = trait_ref.trait_;
    let impl_type = if impl_id.lookup(db.upcast()).container.module(db.upcast()).krate == krate {
-        chalk_rust_ir::ImplType::Local
+        rust_ir::ImplType::Local
    } else {
-        chalk_rust_ir::ImplType::External
+        rust_ir::ImplType::External
    };
    let where_clauses = convert_where_clauses(db, impl_id.into(), &bound_vars);
    let negative = impl_data.is_negative;
@@ -331,13 +335,9 @@ fn impl_def_datum(
    );
    let trait_ref = trait_ref.to_chalk(db);
-    let polarity = if negative {
+    let polarity = if negative { rust_ir::Polarity::Negative } else { rust_ir::Polarity::Positive };
-        chalk_rust_ir::Polarity::Negative
-    } else {
-        chalk_rust_ir::Polarity::Positive
-    };
-    let impl_datum_bound = chalk_rust_ir::ImplDatumBound { trait_ref, where_clauses };
+    let impl_datum_bound = rust_ir::ImplDatumBound { trait_ref, where_clauses };
    let trait_data = db.trait_data(trait_);
    let associated_ty_value_ids = impl_data
        .items
@@ -395,8 +395,8 @@ fn type_alias_associated_ty_value(
        .associated_type_by_name(&type_alias_data.name)
        .expect("assoc ty value should not exist"); // validated when building the impl data as well
    let ty = db.ty(type_alias.into());
-    let value_bound = chalk_rust_ir::AssociatedTyValueBound { ty: ty.value.to_chalk(db) };
+    let value_bound = rust_ir::AssociatedTyValueBound { ty: ty.value.to_chalk(db) };
-    let value = chalk_rust_ir::AssociatedTyValue {
+    let value = rust_ir::AssociatedTyValue {
        impl_id: Impl::ImplDef(impl_id).to_chalk(db),
        associated_ty_id: assoc_ty.to_chalk(db),
        value: make_binders(value_bound, ty.num_binders),
@@ -414,7 +414,7 @@ pub(crate) fn fn_def_datum_query(
    let sig = db.callable_item_signature(callable_def);
    let bound_vars = Substs::bound_vars(&generic_params, DebruijnIndex::INNERMOST);
    let where_clauses = convert_where_clauses(db, callable_def.into(), &bound_vars);
-    let bound = chalk_rust_ir::FnDefDatumBound {
+    let bound = rust_ir::FnDefDatumBound {
        // Note: Chalk doesn't actually use this information yet as far as I am aware, but we provide it anyway
        argument_types: sig.value.params().iter().map(|ty| ty.clone().to_chalk(db)).collect(),
        return_type: sig.value.ret().clone().to_chalk(db),
@@ -460,14 +460,14 @@ impl From<crate::traits::GlobalImplId> for ImplId {
    }
 }
-impl From<chalk_rust_ir::AssociatedTyValueId<Interner>> for crate::traits::AssocTyValueId {
+impl From<rust_ir::AssociatedTyValueId<Interner>> for crate::traits::AssocTyValueId {
-    fn from(id: chalk_rust_ir::AssociatedTyValueId<Interner>) -> Self {
+    fn from(id: rust_ir::AssociatedTyValueId<Interner>) -> Self {
        Self::from_intern_id(id.0)
    }
 }
-impl From<crate::traits::AssocTyValueId> for chalk_rust_ir::AssociatedTyValueId<Interner> {
+impl From<crate::traits::AssocTyValueId> for rust_ir::AssociatedTyValueId<Interner> {
    fn from(assoc_ty_value_id: crate::traits::AssocTyValueId) -> Self {
-        chalk_rust_ir::AssociatedTyValueId(assoc_ty_value_id.as_intern_id())
+        rust_ir::AssociatedTyValueId(assoc_ty_value_id.as_intern_id())
    }
 }
diff --git a/crates/ra_hir_ty/src/traits/chalk/interner.rs b/crates/ra_hir_ty/src/traits/chalk/interner.rs
index 2a27f8ed8..e27074ba6 100644
--- a/crates/ra_hir_ty/src/traits/chalk/interner.rs
+++ b/crates/ra_hir_ty/src/traits/chalk/interner.rs
@@ -11,17 +11,17 @@ use std::{fmt, sync::Arc};
 pub struct Interner;
 pub type AssocTypeId = chalk_ir::AssocTypeId<Interner>;
-pub type AssociatedTyDatum = chalk_rust_ir::AssociatedTyDatum<Interner>;
+pub type AssociatedTyDatum = chalk_solve::rust_ir::AssociatedTyDatum<Interner>;
 pub type TraitId = chalk_ir::TraitId<Interner>;
-pub type TraitDatum = chalk_rust_ir::TraitDatum<Interner>;
+pub type TraitDatum = chalk_solve::rust_ir::TraitDatum<Interner>;
 pub type AdtId = chalk_ir::AdtId<Interner>;
-pub type StructDatum = chalk_rust_ir::AdtDatum<Interner>;
+pub type StructDatum = chalk_solve::rust_ir::AdtDatum<Interner>;
 pub type ImplId = chalk_ir::ImplId<Interner>;
-pub type ImplDatum = chalk_rust_ir::ImplDatum<Interner>;
+pub type ImplDatum = chalk_solve::rust_ir::ImplDatum<Interner>;
-pub type AssociatedTyValueId = chalk_rust_ir::AssociatedTyValueId<Interner>;
+pub type AssociatedTyValueId = chalk_solve::rust_ir::AssociatedTyValueId<Interner>;
-pub type AssociatedTyValue = chalk_rust_ir::AssociatedTyValue<Interner>;
+pub type AssociatedTyValue = chalk_solve::rust_ir::AssociatedTyValue<Interner>;
 pub type FnDefId = chalk_ir::FnDefId<Interner>;
-pub type FnDefDatum = chalk_rust_ir::FnDefDatum<Interner>;
+pub type FnDefDatum = chalk_solve::rust_ir::FnDefDatum<Interner>;
 impl chalk_ir::interner::Interner for Interner {
    type InternedType = Box<chalk_ir::TyData<Self>>; // FIXME use Arc?
diff --git a/crates/ra_hir_ty/src/traits/chalk/mapping.rs b/crates/ra_hir_ty/src/traits/chalk/mapping.rs
index 7082cb095..5f6daf842 100644
--- a/crates/ra_hir_ty/src/traits/chalk/mapping.rs
+++ b/crates/ra_hir_ty/src/traits/chalk/mapping.rs
@@ -7,6 +7,7 @@ use chalk_ir::{
    cast::Cast, fold::shift::Shift, interner::HasInterner, PlaceholderIndex, Scalar, TypeName,
    UniverseIndex,
 };
+use chalk_solve::rust_ir;
 use hir_def::{type_ref::Mutability, AssocContainerId, GenericDefId, Lookup, TypeAliasId};
 use ra_db::salsa::InternKey;
@@ -106,7 +107,7 @@ impl ToChalk for Ty {
                })
            }
            chalk_ir::TyData::BoundVar(idx) => Ty::Bound(idx),
-            chalk_ir::TyData::InferenceVar(_iv) => Ty::Unknown,
+            chalk_ir::TyData::InferenceVar(_iv, _kind) => Ty::Unknown,
            chalk_ir::TyData::Dyn(where_clauses) => {
                assert_eq!(where_clauses.bounds.binders.len(&Interner), 1);
                let predicates = where_clauses
@@ -232,12 +233,13 @@ impl ToChalk for TypeCtor {
                let id = callable_def.to_chalk(db);
                TypeName::FnDef(id)
            }
+            TypeCtor::Never => TypeName::Never,
            TypeCtor::Int(Uncertain::Unknown)
            | TypeCtor::Float(Uncertain::Unknown)
            | TypeCtor::Adt(_)
            | TypeCtor::Array
            | TypeCtor::FnPtr { .. }
-            | TypeCtor::Never
            | TypeCtor::Closure { .. } => {
                // other TypeCtors get interned and turned into a chalk StructId
                let struct_id = db.intern_type_ctor(self).into();
@@ -273,13 +275,14 @@ impl ToChalk for TypeCtor {
            TypeName::Slice => TypeCtor::Slice,
            TypeName::Ref(mutability) => TypeCtor::Ref(from_chalk(db, mutability)),
            TypeName::Str => TypeCtor::Str,
+            TypeName::Never => TypeCtor::Never,
            TypeName::FnDef(fn_def_id) => {
                let callable_def = from_chalk(db, fn_def_id);
                TypeCtor::FnDef(callable_def)
            }
-            TypeName::Error => {
+            TypeName::Array | TypeName::Error => {
                // this should not be reached, since we don't represent TypeName::Error with TypeCtor
                unreachable!()
            }
@@ -508,7 +511,7 @@ where
    fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::Canonical<T::Chalk> {
        let parameter = chalk_ir::CanonicalVarKind::new(
-            chalk_ir::VariableKind::Ty,
+            chalk_ir::VariableKind::Ty(chalk_ir::TyKind::General),
            chalk_ir::UniverseIndex::ROOT,
        );
        let value = self.value.to_chalk(db);
@@ -579,17 +582,17 @@ impl ToChalk for builtin::BuiltinImplData {
    type Chalk = ImplDatum;
    fn to_chalk(self, db: &dyn HirDatabase) -> ImplDatum {
-        let impl_type = chalk_rust_ir::ImplType::External;
+        let impl_type = rust_ir::ImplType::External;
        let where_clauses = self.where_clauses.into_iter().map(|w| w.to_chalk(db)).collect();
        let impl_datum_bound =
-            chalk_rust_ir::ImplDatumBound { trait_ref: self.trait_ref.to_chalk(db), where_clauses };
+            rust_ir::ImplDatumBound { trait_ref: self.trait_ref.to_chalk(db), where_clauses };
        let associated_ty_value_ids =
            self.assoc_ty_values.into_iter().map(|v| v.to_chalk(db)).collect();
-        chalk_rust_ir::ImplDatum {
+        rust_ir::ImplDatum {
            binders: make_binders(impl_datum_bound, self.num_vars),
            impl_type,
-            polarity: chalk_rust_ir::Polarity::Positive,
+            polarity: rust_ir::Polarity::Positive,
            associated_ty_value_ids,
        }
    }
@@ -604,9 +607,9 @@ impl ToChalk for builtin::BuiltinImplAssocTyValueData {
    fn to_chalk(self, db: &dyn HirDatabase) -> AssociatedTyValue {
        let ty = self.value.to_chalk(db);
-        let value_bound = chalk_rust_ir::AssociatedTyValueBound { ty };
+        let value_bound = rust_ir::AssociatedTyValueBound { ty };
-        chalk_rust_ir::AssociatedTyValue {
+        rust_ir::AssociatedTyValue {
            associated_ty_id: self.assoc_ty_id.to_chalk(db),
            impl_id: self.impl_.to_chalk(db),
            value: make_binders(value_bound, self.num_vars),
@@ -628,7 +631,7 @@ where
    chalk_ir::Binders::new(
        chalk_ir::VariableKinds::from(
            &Interner,
-            std::iter::repeat(chalk_ir::VariableKind::Ty).take(num_vars),
+            std::iter::repeat(chalk_ir::VariableKind::Ty(chalk_ir::TyKind::General)).take(num_vars),
        ),
        value,
    )
@@ -655,7 +658,7 @@ pub(super) fn generic_predicate_to_inline_bound(
    db: &dyn HirDatabase,
    pred: &GenericPredicate,
    self_ty: &Ty,
-) -> Option<chalk_rust_ir::InlineBound<Interner>> {
+) -> Option<rust_ir::InlineBound<Interner>> {
    // An InlineBound is like a GenericPredicate, except the self type is left out.
    // We don't have a special type for this, but Chalk does.
    match pred {
@@ -670,8 +673,8 @@ pub(super) fn generic_predicate_to_inline_bound(
                .map(|ty| ty.clone().to_chalk(db).cast(&Interner))
                .collect();
            let trait_bound =
-                chalk_rust_ir::TraitBound { trait_id: trait_ref.trait_.to_chalk(db), args_no_self };
+                rust_ir::TraitBound { trait_id: trait_ref.trait_.to_chalk(db), args_no_self };
-            Some(chalk_rust_ir::InlineBound::TraitBound(trait_bound))
+            Some(rust_ir::InlineBound::TraitBound(trait_bound))
        }
        GenericPredicate::Projection(proj) => {
            if &proj.projection_ty.parameters[0] != self_ty {
@@ -685,16 +688,13 @@ pub(super) fn generic_predicate_to_inline_bound(
                .iter()
                .map(|ty| ty.clone().to_chalk(db).cast(&Interner))
                .collect();
-            let alias_eq_bound = chalk_rust_ir::AliasEqBound {
+            let alias_eq_bound = rust_ir::AliasEqBound {
                value: proj.ty.clone().to_chalk(db),
-                trait_bound: chalk_rust_ir::TraitBound {
+                trait_bound: rust_ir::TraitBound { trait_id: trait_.to_chalk(db), args_no_self },
-                    trait_id: trait_.to_chalk(db),
-                    args_no_self,
-                },
                associated_ty_id: proj.projection_ty.associated_ty.to_chalk(db),
                parameters: Vec::new(), // FIXME we don't support generic associated types yet
            };
-            Some(chalk_rust_ir::InlineBound::AliasEqBound(alias_eq_bound))
+            Some(rust_ir::InlineBound::AliasEqBound(alias_eq_bound))
        }
        GenericPredicate::Error => None,
    }