use crate::ty::free_region_map::FreeRegionRelations;
use crate::ty::subst::{GenericArg, GenericArgKind, InternalSubsts, SubstsRef};
use crate::ty::{self, GenericParamDefKind, Ty, TyCtxt};
-use errors::{struct_span_err, DiagnosticBuilder};
use rustc::session::config::nightly_options;
use rustc_data_structures::fx::FxHashMap;
use rustc_data_structures::sync::Lrc;
+use rustc_errors::{struct_span_err, DiagnosticBuilder};
use rustc_hir as hir;
use rustc_hir::def_id::{DefId, DefIdMap};
use rustc_hir::Node;