+use rustc::mir::traversal;
+use rustc::mir::{self, BasicBlock, BasicBlockData, Body, Location, Statement, Terminator};
+use rustc::ty::{self, TyCtxt};
use rustc_ast::ast::{self, MetaItem};
use rustc_ast_pretty::pprust;
-use rustc_span::symbol::{sym, Symbol};
-
use rustc_data_structures::work_queue::WorkQueue;
+use rustc_hir::def_id::DefId;
use rustc_index::bit_set::{BitSet, HybridBitSet};
use rustc_index::vec::Idx;
-
-use rustc::mir::traversal;
-use rustc::mir::{self, BasicBlock, BasicBlockData, Body, Location, Statement, Terminator};
-use rustc::session::Session;
-use rustc::ty::{self, TyCtxt};
-use rustc_hir::def_id::DefId;
+use rustc_session::Session;
+use rustc_span::symbol::{sym, Symbol};
use std::borrow::Borrow;
use std::fmt;