diff --git a/src/librustc/middle/traits/project.rs b/src/librustc/middle/traits/project.rs
index e1d811d450d..0c857692ad1 100644
--- a/src/librustc/middle/traits/project.rs
+++ b/src/librustc/middle/traits/project.rs
@@ -26,9 +26,8 @@ use super::util;
 use middle::def_id::DefId;
 use middle::infer::{self, TypeOrigin};
 use middle::subst::Subst;
-use middle::ty::{self, ToPredicate, RegionEscape, HasTypeFlags, ToPolyTraitRef, Ty, TyCtxt};
+use middle::ty::{self, ToPredicate, ToPolyTraitRef, Ty, TyCtxt};
 use middle::ty::fold::{TypeFoldable, TypeFolder};
-use rustc_front::hir;
 use syntax::parse::token;
 use syntax::ast;
 use util::common::FN_OUTPUT_NAME;
diff --git a/src/librustc/middle/traits/specialize/mod.rs b/src/librustc/middle/traits/specialize/mod.rs
index b557db9a8b2..a5b3c667fc0 100644
--- a/src/librustc/middle/traits/specialize/mod.rs
+++ b/src/librustc/middle/traits/specialize/mod.rs
@@ -26,7 +26,7 @@ use middle::infer::{self, InferCtxt, TypeOrigin};
 use middle::region;
 use middle::subst::{Subst, Substs};
 use middle::traits::ProjectionMode;
-use middle::ty;
+use middle::ty::{self, TyCtxt};
 use syntax::codemap::DUMMY_SP;
 
 pub mod specialization_graph;
@@ -119,7 +119,7 @@ pub fn translate_substs<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
 /// Specialization is determined by the sets of types to which the impls apply;
 /// impl1 specializes impl2 if it applies to a subset of the types impl2 applies
 /// to.
-pub fn specializes(tcx: &ty::ctxt, impl1_def_id: DefId, impl2_def_id: DefId) -> bool {
+pub fn specializes(tcx: &TyCtxt, impl1_def_id: DefId, impl2_def_id: DefId) -> bool {
     // The feature gate should prevent introducing new specializations, but not
     // taking advantage of upstream ones.
     if !tcx.sess.features.borrow().specialization &&
diff --git a/src/librustc/middle/traits/specialize/specialization_graph.rs b/src/librustc/middle/traits/specialize/specialization_graph.rs
index 77588a3e070..4af8e1fe0a8 100644
--- a/src/librustc/middle/traits/specialize/specialization_graph.rs
+++ b/src/librustc/middle/traits/specialize/specialization_graph.rs
@@ -17,7 +17,7 @@ use middle::cstore::CrateStore;
 use middle::def_id::DefId;
 use middle::infer;
 use middle::traits::{self, ProjectionMode};
-use middle::ty::{self, ImplOrTraitItem, TraitDef, TypeFoldable};
+use middle::ty::{self, TyCtxt, ImplOrTraitItem, TraitDef, TypeFoldable};
 use syntax::ast::Name;
 use util::nodemap::DefIdMap;
 
@@ -57,7 +57,7 @@ impl Graph {
     /// conflicts with it (has overlap, but neither specializes the other),
     /// information about the area of overlap is returned in the `Err`.
     pub fn insert<'a, 'tcx>(&mut self,
-                            tcx: &'a ty::ctxt<'tcx>,
+                            tcx: &'a TyCtxt<'tcx>,
                             impl_def_id: DefId)
                             -> Result<(), Overlap<'a, 'tcx>> {
         assert!(impl_def_id.is_local());
@@ -177,7 +177,7 @@ impl Node {
     }
 
     /// Iterate over the items defined directly by the given (impl or trait) node.
-    pub fn items<'a, 'tcx>(&self, tcx: &'a ty::ctxt<'tcx>) -> NodeItems<'a, 'tcx> {
+    pub fn items<'a, 'tcx>(&self, tcx: &'a TyCtxt<'tcx>) -> NodeItems<'a, 'tcx> {
         match *self {
             Node::Impl(impl_def_id) => {
                 NodeItems::Impl {
@@ -207,7 +207,7 @@ impl Node {
 /// An iterator over the items defined within a trait or impl.
 pub enum NodeItems<'a, 'tcx: 'a> {
     Impl {
-        tcx: &'a ty::ctxt<'tcx>,
+        tcx: &'a TyCtxt<'tcx>,
         items: cell::Ref<'a, Vec<ty::ImplOrTraitItemId>>,
         idx: usize,
     },
@@ -319,7 +319,7 @@ impl<'a, 'tcx> Iterator for ConstDefs<'a, 'tcx> {
 impl<'a, 'tcx> Ancestors<'a, 'tcx> {
     /// Search the items from the given ancestors, returning each type definition
     /// with the given name.
-    pub fn type_defs(self, tcx: &'a ty::ctxt<'tcx>, name: Name) -> TypeDefs<'a, 'tcx> {
+    pub fn type_defs(self, tcx: &'a TyCtxt<'tcx>, name: Name) -> TypeDefs<'a, 'tcx> {
         let iter = self.flat_map(move |node| {
             node.items(tcx)
                 .filter_map(move |item| {
@@ -340,7 +340,7 @@ impl<'a, 'tcx> Ancestors<'a, 'tcx> {
 
     /// Search the items from the given ancestors, returning each fn definition
     /// with the given name.
-    pub fn fn_defs(self, tcx: &'a ty::ctxt<'tcx>, name: Name) -> FnDefs<'a, 'tcx> {
+    pub fn fn_defs(self, tcx: &'a TyCtxt<'tcx>, name: Name) -> FnDefs<'a, 'tcx> {
         let iter = self.flat_map(move |node| {
             node.items(tcx)
                 .filter_map(move |item| {
@@ -361,7 +361,7 @@ impl<'a, 'tcx> Ancestors<'a, 'tcx> {
 
     /// Search the items from the given ancestors, returning each const
     /// definition with the given name.
-    pub fn const_defs(self, tcx: &'a ty::ctxt<'tcx>, name: Name) -> ConstDefs<'a, 'tcx> {
+    pub fn const_defs(self, tcx: &'a TyCtxt<'tcx>, name: Name) -> ConstDefs<'a, 'tcx> {
         let iter = self.flat_map(move |node| {
             node.items(tcx)
                 .filter_map(move |item| {
diff --git a/src/librustc/middle/ty/trait_def.rs b/src/librustc/middle/ty/trait_def.rs
index c4e820bde8f..3d7b3bf2634 100644
--- a/src/librustc/middle/ty/trait_def.rs
+++ b/src/librustc/middle/ty/trait_def.rs
@@ -192,7 +192,7 @@ impl<'tcx> TraitDef<'tcx> {
     /// overlap information if the impl overlaps but does not specialize an
     /// existing impl.
     pub fn add_impl_for_specialization<'a>(&self,
-                                           tcx: &'a ctxt<'tcx>,
+                                           tcx: &'a TyCtxt<'tcx>,
                                            impl_def_id: DefId)
                                            -> Result<(), traits::Overlap<'a, 'tcx>> {
         assert!(impl_def_id.is_local());
diff --git a/src/librustc_metadata/decoder.rs b/src/librustc_metadata/decoder.rs
index cf65d7a522a..38a2a7794bc 100644
--- a/src/librustc_metadata/decoder.rs
+++ b/src/librustc_metadata/decoder.rs
@@ -34,7 +34,6 @@ use middle::lang_items;
 use middle::subst;
 use middle::ty::{ImplContainer, TraitContainer};
 use middle::ty::{self, Ty, TyCtxt, TypeFoldable, VariantKind};
-use middle::traits;
 
 use rustc_const_eval::ConstInt;
 
diff --git a/src/librustc_metadata/encoder.rs b/src/librustc_metadata/encoder.rs
index 707657cfa26..41baa0b1591 100644
--- a/src/librustc_metadata/encoder.rs
+++ b/src/librustc_metadata/encoder.rs
@@ -25,6 +25,7 @@ use middle::def_id::{CRATE_DEF_INDEX, DefId};
 use middle::dependency_format::Linkage;
 use middle::stability;
 use middle::subst;
+use middle::traits::specialization_graph;
 use middle::ty::{self, Ty, TyCtxt};
 use middle::ty::util::IntTypeExt;
 
diff --git a/src/librustc_mir/mir_map.rs b/src/librustc_mir/mir_map.rs
index 4aa8b82ec54..13521de78af 100644
--- a/src/librustc_mir/mir_map.rs
+++ b/src/librustc_mir/mir_map.rs
@@ -28,6 +28,7 @@ use rustc::mir::mir_map::MirMap;
 use rustc::middle::infer;
 use rustc::middle::region::CodeExtentData;
 use rustc::middle::traits::ProjectionMode;
+use rustc::middle::ty::{self, Ty, TyCtxt};
 use rustc::util::common::ErrorReported;
 use rustc::util::nodemap::NodeMap;
 use rustc_front::hir;
diff --git a/src/librustc_trans/trans/meth.rs b/src/librustc_trans/trans/meth.rs
index 0f5c1cf87f1..2965e44bc17 100644
--- a/src/librustc_trans/trans/meth.rs
+++ b/src/librustc_trans/trans/meth.rs
@@ -478,7 +478,7 @@ pub struct ImplMethod<'tcx> {
 }
 
 /// Locates the applicable definition of a method, given its name.
-pub fn get_impl_method<'tcx>(tcx: &ty::ctxt<'tcx>,
+pub fn get_impl_method<'tcx>(tcx: &TyCtxt<'tcx>,
                              impl_def_id: DefId,
                              substs: Substs<'tcx>,
                              name: Name)
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 534f10103b5..0d5e25efd68 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -864,7 +864,7 @@ fn check_method_body<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>,
     check_bare_fn(ccx, &sig.decl, body, id, span, fty, param_env);
 }
 
-fn report_forbidden_specialization(tcx: &ty::ctxt,
+fn report_forbidden_specialization(tcx: &TyCtxt,
                                    impl_item: &hir::ImplItem,
                                    parent_impl: DefId)
 {
@@ -887,7 +887,7 @@ fn report_forbidden_specialization(tcx: &ty::ctxt,
     err.emit();
 }
 
-fn check_specialization_validity<'tcx>(tcx: &ty::ctxt<'tcx>, trait_def: &ty::TraitDef<'tcx>,
+fn check_specialization_validity<'tcx>(tcx: &TyCtxt<'tcx>, trait_def: &ty::TraitDef<'tcx>,
                                        impl_id: DefId, impl_item: &hir::ImplItem)
 {
     let ancestors = trait_def.ancestors(impl_id);
diff --git a/src/librustc_typeck/coherence/overlap.rs b/src/librustc_typeck/coherence/overlap.rs
index 4a5dbe20b78..e4994eaa255 100644
--- a/src/librustc_typeck/coherence/overlap.rs
+++ b/src/librustc_typeck/coherence/overlap.rs
@@ -15,7 +15,6 @@
 use middle::cstore::CrateStore;
 use middle::traits;
 use middle::ty::{self, TyCtxt};
-use middle::infer;
 use syntax::ast;
 use rustc::dep_graph::DepNode;
 use rustc_front::hir;
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index a5f0fbbd094..fbaf28332c4 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -247,11 +247,10 @@ const KNOWN_FEATURES: &'static [(&'static str, &'static str, Option<u32>, Status
     ("inclusive_range_syntax", "1.7.0", Some(28237), Active),
 
     // `expr?`
-    ("question_mark", "1.9.0", Some(31436), Active)
+    ("question_mark", "1.9.0", Some(31436), Active),
 
     // impl specialization (RFC 1210)
-    // TODO: update with issue number (once it exists), before landing
-    ("specialization", "1.7.0", None, Active),
+    ("specialization", "1.7.0", Some(31844), Active),
 ];
 // (changing above list without updating src/doc/reference.md makes @cmr sad)