Erased functions do not take a func spec

crates/compiler/mono/src/tail_recursion.rs

@@ -813,6 +813,7 @@ impl<'a> TrmcEnv<'a> {
             ret_layout: proc.ret_layout,
             is_self_recursive: SelfRecursive::NotSelfRecursive,
             host_exposed_layouts: proc.host_exposed_layouts.clone(),
+            is_erased: proc.is_erased,
         }
     }