use rustc_hir::{is_range_literal, Expr, ExprKind, Node};
use rustc_middle::ty::layout::{IntegerExt, LayoutOf, SizeSkeleton};
use rustc_middle::ty::subst::SubstsRef;
-use rustc_middle::ty::{self, AdtKind, DefIdTree, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, AdtKind, DefIdTree, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable};
use rustc_span::source_map;
use rustc_span::symbol::sym;
use rustc_span::{Span, Symbol, DUMMY_SP};