use rustc::hir::map::Map;
-use rustc::session::parse::feature_err;
use rustc::ty::subst::{GenericArgKind, InternalSubsts, Subst};
use rustc::ty::util::IntTypeExt;
use rustc::ty::{self, DefIdTree, Ty, TyCtxt, TypeFoldable};
use rustc_hir::intravisit;
use rustc_hir::intravisit::Visitor;
use rustc_hir::Node;
+use rustc_session::parse::feature_err;
use rustc_span::symbol::{sym, Ident};
use rustc_span::{Span, DUMMY_SP};
use rustc_trait_selection::traits;