diff --git a/kani-compiler/src/codegen_cprover_gotoc/codegen/typ.rs b/kani-compiler/src/codegen_cprover_gotoc/codegen/typ.rs
index aec9d8143818..740dc46b216b 100644
--- a/kani-compiler/src/codegen_cprover_gotoc/codegen/typ.rs
+++ b/kani-compiler/src/codegen_cprover_gotoc/codegen/typ.rs
@@ -332,10 +332,10 @@ impl<'tcx> GotocCtx<'tcx> {
         ty: Ty<'tcx>,
         args: ty::GenericArgsRef<'tcx>,
     ) -> ty::PolyFnSig<'tcx> {
-        let sig = args.as_coroutine().poly_sig();
+        let sig = args.as_coroutine().sig();
 
         let bound_vars = self.tcx.mk_bound_variable_kinds_from_iter(
-            sig.bound_vars().iter().chain(iter::once(ty::BoundVariableKind::Region(ty::BrEnv))),
+            iter::once(ty::BoundVariableKind::Region(ty::BrEnv)),
         );
         let br = ty::BoundRegion {
             var: ty::BoundVar::from_usize(bound_vars.len() - 1),
@@ -349,7 +349,6 @@ impl<'tcx> GotocCtx<'tcx> {
         let pin_args = self.tcx.mk_args(&[env_ty.into()]);
         let env_ty = Ty::new_adt(self.tcx, pin_adt_ref, pin_args);
 
-        let sig = sig.skip_binder();
         // The `FnSig` and the `ret_ty` here is for a coroutines main
         // `coroutine::resume(...) -> CoroutineState` function in case we
         // have an ordinary coroutine, or the `Future::poll(...) -> Poll`