fix fallout

Author: lcnr

compiler/rustc_middle/src/ty/walk.rs

@@ -178,7 +178,7 @@ fn push_inner<'tcx>(stack: &mut TypeWalkerStack<'tcx>, parent: GenericArg<'tcx>)
             | ty::FnDef(_, substs) => {
                 stack.extend(substs.iter().rev());
             }
-            ty::Tuple(ts) => stack.extend(ts.as_substs().iter().rev()),
+            ty::Tuple(ts) => stack.extend(ts.iter().map(|ty| ty.into()).rev()),
             ty::GeneratorWitness(ts) => {
                 stack.extend(ts.skip_binder().iter().rev().map(|ty| ty.into()));
             }

compiler/rustc_traits/src/chalk/lowering.rs

@@ -329,9 +329,13 @@ impl<'tcx> LowerInto<'tcx, chalk_ir::Ty<RustInterner<'tcx>>> for Ty<'tcx> {
             ),
             ty::GeneratorWitness(_) => unimplemented!(),
             ty::Never => chalk_ir::TyKind::Never,
-            ty::Tuple(types) => {
-                chalk_ir::TyKind::Tuple(types.len(), types.as_substs().lower_into(interner))
-            }
+            ty::Tuple(types) => chalk_ir::TyKind::Tuple(
+                types.len(),
+                chalk_ir::Substitution::from_iter(
+                    interner,
+                    types.iter().map(|ty| ty::subst::GenericArg::from(ty).lower_into(interner)),
+                ),
+            ),
             ty::Projection(proj) => chalk_ir::TyKind::Alias(proj.lower_into(interner)),
             ty::Opaque(def_id, substs) => {
                 chalk_ir::TyKind::Alias(chalk_ir::AliasTy::Opaque(chalk_ir::OpaqueTy {
@@ -403,9 +407,9 @@ impl<'tcx> LowerInto<'tcx, Ty<'tcx>> for &chalk_ir::Ty<RustInterner<'tcx>> {
             TyKind::Generator(..) => unimplemented!(),
             TyKind::GeneratorWitness(..) => unimplemented!(),
             TyKind::Never => ty::Never,
-            TyKind::Tuple(_len, substitution) => {
-                ty::Tuple(substitution.lower_into(interner).try_as_type_list().unwrap())
-            }
+            TyKind::Tuple(_len, substitution) => ty::Tuple(interner.tcx.mk_type_list(
+                substitution.iter(interner).map(|subst| subst.lower_into(interner).expect_ty()),
+            )),
             TyKind::Slice(ty) => ty::Slice(ty.lower_into(interner)),
             TyKind::Raw(mutbl, ty) => ty::RawPtr(ty::TypeAndMut {
                 ty: ty.lower_into(interner),