Auto merge of #34772 - jseyfried:cleanup_interner, r=eddyb

Start cleaning up the string interner

r? @eddyb

16 files changed, 145 insertions, 395 deletions

diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index eef2b6e6f37..ba59c2afc76 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -211,7 +211,7 @@ pub fn compile_input(sess: &Session,
             }
 
             // Discard interned strings as they are no longer required.
-            token::get_ident_interner().clear();
+            token::clear_ident_interner();
 
             Ok((outputs, trans))
         })??
@@ -480,7 +480,7 @@ pub fn phase_1_parse_input<'a>(sess: &'a Session,
                                input: &Input)
                                -> PResult<'a, ast::Crate> {
     // These may be left in an incoherent state after a previous compile.
-    // `clear_tables` and `get_ident_interner().clear()` can be used to free
+    // `clear_tables` and `clear_ident_interner` can be used to free
     // memory, but they do not restore the initial state.
     syntax::ext::mtwt::reset_tables();
     token::reset_ident_interner();
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index c9569a63436..84e04031923 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -97,7 +97,7 @@ use rustc::session::early_error;
 use syntax::{ast, json};
 use syntax::codemap::{CodeMap, FileLoader, RealFileLoader};
 use syntax::feature_gate::{GatedCfg, UnstableFeatures};
-use syntax::parse::{self, PResult, token};
+use syntax::parse::{self, PResult};
 use syntax_pos::MultiSpan;
 use errors::emitter::Emitter;
 
@@ -201,7 +201,7 @@ pub fn run_compiler_with_file_loader<'a, L>(args: &[String],
     };
 
     let dep_graph = DepGraph::new(sopts.build_dep_graph());
-    let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+    let cstore = Rc::new(CStore::new(&dep_graph));
     let codemap = Rc::new(CodeMap::with_file_loader(loader));
     let sess = session::build_session_with_codemap(sopts,
                                                    &dep_graph,
@@ -432,7 +432,7 @@ impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
                     return None;
                 }
                 let dep_graph = DepGraph::new(sopts.build_dep_graph());
-                let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+                let cstore = Rc::new(CStore::new(&dep_graph));
                 let sess = build_session(sopts.clone(),
                     &dep_graph,
                     None,
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index 15a0ab0f284..911becd3f56 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -106,7 +106,7 @@ fn test_env<F>(source_string: &str,
 
     let dep_graph = DepGraph::new(false);
     let _ignore = dep_graph.in_ignore();
-    let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+    let cstore = Rc::new(CStore::new(&dep_graph));
     let sess = session::build_session_(options, &dep_graph, None, diagnostic_handler,
                                        Rc::new(CodeMap::new()), cstore.clone());
     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index 269e284b22d..d4443c6d09d 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -557,7 +557,6 @@ impl<'a> CrateReader<'a> {
         let source_name = format!("<{} macros>", item.ident);
         let mut macros = vec![];
         decoder::each_exported_macro(ekrate.metadata.as_slice(),
-                                     &self.cstore.intr,
             |name, attrs, span, body| {
                 // NB: Don't use parse::parse_tts_from_source_str because it parses with
                 // quote_depth > 0.
diff --git a/src/librustc_metadata/csearch.rs b/src/librustc_metadata/csearch.rs
index 95e3c53ecb4..850d6c91f66 100644
--- a/src/librustc_metadata/csearch.rs
+++ b/src/librustc_metadata/csearch.rs
@@ -127,7 +127,7 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
     {
         self.dep_graph.read(DepNode::MetaData(def));
         let cdata = self.get_crate_data(def.krate);
-        decoder::get_adt_def(&self.intr, &cdata, def.index, tcx)
+        decoder::get_adt_def(&cdata, def.index, tcx)
     }
 
     fn method_arg_names(&self, did: DefId) -> Vec<String>
@@ -140,13 +140,13 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
     fn item_name(&self, def: DefId) -> ast::Name {
         self.dep_graph.read(DepNode::MetaData(def));
         let cdata = self.get_crate_data(def.krate);
-        decoder::get_item_name(&self.intr, &cdata, def.index)
+        decoder::get_item_name(&cdata, def.index)
     }
 
     fn opt_item_name(&self, def: DefId) -> Option<ast::Name> {
         self.dep_graph.read(DepNode::MetaData(def));
         let cdata = self.get_crate_data(def.krate);
-        decoder::maybe_get_item_name(&self.intr, &cdata, def.index)
+        decoder::maybe_get_item_name(&cdata, def.index)
     }
 
     fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId>
@@ -176,7 +176,7 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
     {
         self.dep_graph.read(DepNode::MetaData(def));
         let cdata = self.get_crate_data(def.krate);
-        decoder::get_provided_trait_methods(self.intr.clone(), &cdata, def.index, tcx)
+        decoder::get_provided_trait_methods(&cdata, def.index, tcx)
     }
 
     fn trait_item_def_ids(&self, def: DefId)
@@ -222,7 +222,7 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
                              -> Vec<Rc<ty::AssociatedConst<'tcx>>> {
         self.dep_graph.read(DepNode::MetaData(def));
         let cdata = self.get_crate_data(def.krate);
-        decoder::get_associated_consts(self.intr.clone(), &cdata, def.index, tcx)
+        decoder::get_associated_consts(&cdata, def.index, tcx)
     }
 
     fn impl_parent(&self, impl_def: DefId) -> Option<DefId> {
@@ -243,11 +243,7 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
     {
         self.dep_graph.read(DepNode::MetaData(def));
         let cdata = self.get_crate_data(def.krate);
-        decoder::get_impl_or_trait_item(
-            self.intr.clone(),
-            &cdata,
-            def.index,
-            tcx)
+        decoder::get_impl_or_trait_item(&cdata, def.index, tcx)
     }
 
     fn is_const_fn(&self, did: DefId) -> bool
@@ -460,7 +456,7 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
     {
         self.dep_graph.read(DepNode::MetaData(def));
         let cdata = self.get_crate_data(def.krate);
-        decoder::get_struct_field_names(&self.intr, &cdata, def.index)
+        decoder::get_struct_field_names(&cdata, def.index)
     }
 
     fn item_children(&self, def_id: DefId) -> Vec<ChildItem>
@@ -469,14 +465,9 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
         let mut result = vec![];
         let crate_data = self.get_crate_data(def_id.krate);
         let get_crate_data = |cnum| self.get_crate_data(cnum);
-        decoder::each_child_of_item(
-            self.intr.clone(), &crate_data,
-            def_id.index, get_crate_data,
-            |def, name, vis| result.push(ChildItem {
-                def: def,
-                name: name,
-                vis: vis
-            }));
+        decoder::each_child_of_item(&crate_data, def_id.index, get_crate_data, |def, name, vis| {
+            result.push(ChildItem { def: def, name: name, vis: vis });
+        });
         result
     }
 
@@ -485,13 +476,9 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
         let mut result = vec![];
         let crate_data = self.get_crate_data(cnum);
         let get_crate_data = |cnum| self.get_crate_data(cnum);
-        decoder::each_top_level_item_of_crate(
-            self.intr.clone(), &crate_data, get_crate_data,
-            |def, name, vis| result.push(ChildItem {
-                def: def,
-                name: name,
-                vis: vis
-            }));
+        decoder::each_top_level_item_of_crate(&crate_data, get_crate_data, |def, name, vis| {
+            result.push(ChildItem { def: def, name: name, vis: vis });
+        });
         result
     }
 
diff --git a/src/librustc_metadata/cstore.rs b/src/librustc_metadata/cstore.rs
index 774d0f7ea18..6baa0ac23f3 100644
--- a/src/librustc_metadata/cstore.rs
+++ b/src/librustc_metadata/cstore.rs
@@ -37,7 +37,6 @@ use flate::Bytes;
 use syntax::ast;
 use syntax::attr;
 use syntax::codemap;
-use syntax::parse::token::IdentInterner;
 use syntax_pos;
 
 pub use middle::cstore::{NativeLibraryKind, LinkagePreference};
@@ -106,13 +105,11 @@ pub struct CStore {
     used_libraries: RefCell<Vec<(String, NativeLibraryKind)>>,
     used_link_args: RefCell<Vec<String>>,
     statically_included_foreign_items: RefCell<NodeSet>,
-    pub intr: Rc<IdentInterner>,
     pub visible_parent_map: RefCell<DefIdMap<DefId>>,
 }
 
 impl CStore {
-    pub fn new(dep_graph: &DepGraph,
-               intr: Rc<IdentInterner>) -> CStore {
+    pub fn new(dep_graph: &DepGraph) -> CStore {
         CStore {
             dep_graph: dep_graph.clone(),
             metas: RefCell::new(FnvHashMap()),
@@ -120,7 +117,6 @@ impl CStore {
             used_crate_sources: RefCell::new(Vec::new()),
             used_libraries: RefCell::new(Vec::new()),
             used_link_args: RefCell::new(Vec::new()),
-            intr: intr,
             statically_included_foreign_items: RefCell::new(NodeSet()),
             visible_parent_map: RefCell::new(FnvHashMap()),
         }
diff --git a/src/librustc_metadata/decoder.rs b/src/librustc_metadata/decoder.rs
index 6d3699e9787..3f5c9a6d3bd 100644
--- a/src/librustc_metadata/decoder.rs
+++ b/src/librustc_metadata/decoder.rs
@@ -53,7 +53,7 @@ use rbml::reader;
 use rbml;
 use rustc_serialize::Decodable;
 use syntax::attr;
-use syntax::parse::token::{self, IdentInterner};
+use syntax::parse::token;
 use syntax::ast;
 use syntax::abi::Abi;
 use syntax::codemap;
@@ -284,17 +284,14 @@ fn item_trait_ref<'a, 'tcx>(doc: rbml::Doc, tcx: TyCtxt<'a, 'tcx, 'tcx>, cdata:
     doc_trait_ref(tp, tcx, cdata)
 }
 
-fn item_name(intr: &IdentInterner, item: rbml::Doc) -> ast::Name {
-    maybe_item_name(intr, item).expect("no item in item_name")
+fn item_name(item: rbml::Doc) -> ast::Name {
+    maybe_item_name(item).expect("no item in item_name")
 }
 
-fn maybe_item_name(intr: &IdentInterner, item: rbml::Doc) -> Option<ast::Name> {
+fn maybe_item_name(item: rbml::Doc) -> Option<ast::Name> {
     reader::maybe_get_doc(item, tag_paths_data_name).map(|name| {
         let string = name.as_str_slice();
-        match intr.find(string) {
-            None => token::intern(string),
-            Some(val) => val,
-        }
+        token::intern(string)
     })
 }
 
@@ -400,8 +397,7 @@ pub fn get_trait_def<'a, 'tcx>(cdata: Cmd,
                       associated_type_names)
 }
 
-pub fn get_adt_def<'a, 'tcx>(intr: &IdentInterner,
-                             cdata: Cmd,
+pub fn get_adt_def<'a, 'tcx>(cdata: Cmd,
                              item_id: DefIndex,
                              tcx: TyCtxt<'a, 'tcx, 'tcx>)
                              -> ty::AdtDefMaster<'tcx>
@@ -412,9 +408,7 @@ pub fn get_adt_def<'a, 'tcx>(intr: &IdentInterner,
             _ => bug!("unexpected family: {:?}", family),
         }
     }
-    fn get_enum_variants<'tcx>(intr: &IdentInterner,
-                               cdata: Cmd,
-                               doc: rbml::Doc) -> Vec<ty::VariantDefData<'tcx, 'tcx>> {
+    fn get_enum_variants<'tcx>(cdata: Cmd, doc: rbml::Doc) -> Vec<ty::VariantDefData<'tcx, 'tcx>> {
         let mut disr_val = 0;
         reader::tagged_docs(doc, tag_items_data_item_variant).map(|p| {
             let did = translated_def_id(cdata, p);
@@ -428,16 +422,14 @@ pub fn get_adt_def<'a, 'tcx>(intr: &IdentInterner,
 
             ty::VariantDefData {
                 did: did,
-                name: item_name(intr, item),
-                fields: get_variant_fields(intr, cdata, item),
+                name: item_name(item),
+                fields: get_variant_fields(cdata, item),
                 disr_val: ConstInt::Infer(disr),
                 kind: expect_variant_kind(item_family(item)),
             }
         }).collect()
     }
-    fn get_variant_fields<'tcx>(intr: &IdentInterner,
-                                cdata: Cmd,
-                                doc: rbml::Doc) -> Vec<ty::FieldDefData<'tcx, 'tcx>> {
+    fn get_variant_fields<'tcx>(cdata: Cmd, doc: rbml::Doc) -> Vec<ty::FieldDefData<'tcx, 'tcx>> {
         let mut index = 0;
         reader::tagged_docs(doc, tag_item_field).map(|f| {
             let ff = item_family(f);
@@ -446,24 +438,23 @@ pub fn get_adt_def<'a, 'tcx>(intr: &IdentInterner,
                 _ => bug!("expected field, found {:?}", ff)
             };
             ty::FieldDefData::new(item_def_id(f, cdata),
-                                  item_name(intr, f),
+                                  item_name(f),
                                   struct_field_family_to_visibility(ff))
         }).chain(reader::tagged_docs(doc, tag_item_unnamed_field).map(|f| {
             let ff = item_family(f);
-            let name = intr.intern(&index.to_string());
+            let name = token::with_ident_interner(|interner| interner.intern(index.to_string()));
             index += 1;
             ty::FieldDefData::new(item_def_id(f, cdata), name,
                                   struct_field_family_to_visibility(ff))
         })).collect()
     }
-    fn get_struct_variant<'tcx>(intr: &IdentInterner,
-                                cdata: Cmd,
+    fn get_struct_variant<'tcx>(cdata: Cmd,
                                 doc: rbml::Doc,
                                 did: DefId) -> ty::VariantDefData<'tcx, 'tcx> {
         ty::VariantDefData {
             did: did,
-            name: item_name(intr, doc),
-            fields: get_variant_fields(intr, cdata, doc),
+            name: item_name(doc),
+            fields: get_variant_fields(cdata, doc),
             disr_val: ConstInt::Infer(0),
             kind: expect_variant_kind(item_family(doc)),
         }
@@ -475,7 +466,7 @@ pub fn get_adt_def<'a, 'tcx>(intr: &IdentInterner,
     let (kind, variants) = match item_family(doc) {
         Enum => {
             (ty::AdtKind::Enum,
-             get_enum_variants(intr, cdata, doc))
+             get_enum_variants(cdata, doc))
         }
         Struct(..) => {
             // Use separate constructor id for unit/tuple structs and reuse did for braced structs.
@@ -483,7 +474,7 @@ pub fn get_adt_def<'a, 'tcx>(intr: &IdentInterner,
                 translated_def_id(cdata, ctor_doc)
             });
             (ty::AdtKind::Struct,
-             vec![get_struct_variant(intr, cdata, doc, ctor_did.unwrap_or(did))])
+             vec![get_struct_variant(cdata, doc, ctor_did.unwrap_or(did))])
         }
         _ => bug!("get_adt_def called on a non-ADT {:?} - {:?}",
                   item_family(doc), did)
@@ -663,8 +654,7 @@ pub fn each_lang_item<F>(cdata: Cmd, mut f: F) -> bool where
     })
 }
 
-fn each_child_of_item_or_crate<F, G>(intr: Rc<IdentInterner>,
-                                     cdata: Cmd,
+fn each_child_of_item_or_crate<F, G>(cdata: Cmd,
                                      item_doc: rbml::Doc,
                                      mut get_crate_data: G,
                                      mut callback: F) where
@@ -690,7 +680,7 @@ fn each_child_of_item_or_crate<F, G>(intr: Rc<IdentInterner>,
         // Get the item.
         if let Some(child_item_doc) = crate_data.get_item(child_def_id.index) {
             // Hand off the item to the callback.
-            let child_name = item_name(&intr, child_item_doc);
+            let child_name = item_name(child_item_doc);
             let def_like = item_to_def_like(crate_data, child_item_doc, child_def_id);
             let visibility = item_visibility(child_item_doc);
             callback(def_like, child_name, visibility);
@@ -711,7 +701,7 @@ fn each_child_of_item_or_crate<F, G>(intr: Rc<IdentInterner>,
                 if let Some(impl_method_doc) = cdata.get_item(impl_item_def_id.index) {
                     if let StaticMethod = item_family(impl_method_doc) {
                         // Hand off the static method to the callback.
-                        let static_method_name = item_name(&intr, impl_method_doc);
+                        let static_method_name = item_name(impl_method_doc);
                         let static_method_def_like = item_to_def_like(cdata, impl_method_doc,
                                                                       impl_item_def_id);
                         callback(static_method_def_like,
@@ -755,13 +745,9 @@ fn each_child_of_item_or_crate<F, G>(intr: Rc<IdentInterner>,
 }
 
 /// Iterates over each child of the given item.
-pub fn each_child_of_item<F, G>(intr: Rc<IdentInterner>,
-                               cdata: Cmd,
-                               id: DefIndex,
-                               get_crate_data: G,
-                               callback: F) where
-    F: FnMut(DefLike, ast::Name, ty::Visibility),
-    G: FnMut(ast::CrateNum) -> Rc<CrateMetadata>,
+pub fn each_child_of_item<F, G>(cdata: Cmd, id: DefIndex, get_crate_data: G, callback: F)
+    where F: FnMut(DefLike, ast::Name, ty::Visibility),
+          G: FnMut(ast::CrateNum) -> Rc<CrateMetadata>,
 {
     // Find the item.
     let item_doc = match cdata.get_item(id) {
@@ -769,40 +755,31 @@ pub fn each_child_of_item<F, G>(intr: Rc<IdentInterner>,
         Some(item_doc) => item_doc,
     };
 
-    each_child_of_item_or_crate(intr,
-                                cdata,
-                                item_doc,
-                                get_crate_data,
-                                callback)
+    each_child_of_item_or_crate(cdata, item_doc, get_crate_data, callback)
 }
 
 /// Iterates over all the top-level crate items.
-pub fn each_top_level_item_of_crate<F, G>(intr: Rc<IdentInterner>,
-                                          cdata: Cmd,
-                                          get_crate_data: G,
-                                          callback: F) where
-    F: FnMut(DefLike, ast::Name, ty::Visibility),
-    G: FnMut(ast::CrateNum) -> Rc<CrateMetadata>,
+pub fn each_top_level_item_of_crate<F, G>(cdata: Cmd, get_crate_data: G, callback: F)
+    where F: FnMut(DefLike, ast::Name, ty::Visibility),
+          G: FnMut(ast::CrateNum) -> Rc<CrateMetadata>,
 {
     let root_doc = rbml::Doc::new(cdata.data());
     let misc_info_doc = reader::get_doc(root_doc, tag_misc_info);
     let crate_items_doc = reader::get_doc(misc_info_doc,
                                           tag_misc_info_crate_items);
 
-    each_child_of_item_or_crate(intr,
-                                cdata,
+    each_child_of_item_or_crate(cdata,
                                 crate_items_doc,
                                 get_crate_data,
                                 callback)
 }
 
-pub fn get_item_name(intr: &IdentInterner, cdata: Cmd, id: DefIndex) -> ast::Name {
-    item_name(intr, cdata.lookup_item(id))
+pub fn get_item_name(cdata: Cmd, id: DefIndex) -> ast::Name {
+    item_name(cdata.lookup_item(id))
 }
 
-pub fn maybe_get_item_name(intr: &IdentInterner, cdata: Cmd, id: DefIndex)
-                         -> Option<ast::Name> {
-    maybe_item_name(intr, cdata.lookup_item(id))
+pub fn maybe_get_item_name(cdata: Cmd, id: DefIndex) -> Option<ast::Name> {
+    maybe_item_name(cdata.lookup_item(id))
 }
 
 pub fn maybe_get_item_ast<'a, 'tcx>(cdata: Cmd, tcx: TyCtxt<'a, 'tcx, 'tcx>, id: DefIndex)
@@ -955,12 +932,9 @@ pub fn get_impl_items(cdata: Cmd, impl_id: DefIndex)
     }).collect()
 }
 
-pub fn get_trait_name(intr: Rc<IdentInterner>,
-                      cdata: Cmd,
-                      id: DefIndex)
-                      -> ast::Name {
+pub fn get_trait_name(cdata: Cmd, id: DefIndex) -> ast::Name {
     let doc = cdata.lookup_item(id);
-    item_name(&intr, doc)
+    item_name(doc)
 }
 
 pub fn is_static_method(cdata: Cmd, id: DefIndex) -> bool {
@@ -973,10 +947,7 @@ pub fn is_static_method(cdata: Cmd, id: DefIndex) -> bool {
     }
 }
 
-pub fn get_impl_or_trait_item<'a, 'tcx>(intr: Rc<IdentInterner>,
-                                        cdata: Cmd,
-                                        id: DefIndex,
-                                        tcx: TyCtxt<'a, 'tcx, 'tcx>)
+pub fn get_impl_or_trait_item<'a, 'tcx>(cdata: Cmd, id: DefIndex, tcx: TyCtxt<'a, 'tcx, 'tcx>)
                                         -> Option<ty::ImplOrTraitItem<'tcx>> {
     let item_doc = cdata.lookup_item(id);
 
@@ -993,7 +964,7 @@ pub fn get_impl_or_trait_item<'a, 'tcx>(intr: Rc<IdentInterner>,
         _ => ImplContainer(container_id),
     };
 
-    let name = item_name(&intr, item_doc);
+    let name = item_name(item_doc);
     let vis = item_visibility(item_doc);
     let defaultness = item_defaultness(item_doc);
 
@@ -1068,8 +1039,7 @@ pub fn get_item_variances(cdata: Cmd, id: DefIndex) -> ty::ItemVariances {
     Decodable::decode(&mut decoder).unwrap()
 }
 
-pub fn get_provided_trait_methods<'a, 'tcx>(intr: Rc<IdentInterner>,
-                                            cdata: Cmd,
+pub fn get_provided_trait_methods<'a, 'tcx>(cdata: Cmd,
                                             id: DefIndex,
                                             tcx: TyCtxt<'a, 'tcx, 'tcx>)
                                             -> Vec<Rc<ty::Method<'tcx>>> {
@@ -1080,10 +1050,7 @@ pub fn get_provided_trait_methods<'a, 'tcx>(intr: Rc<IdentInterner>,
         let mth = cdata.lookup_item(did.index);
 
         if item_sort(mth) == Some('p') {
-            let trait_item = get_impl_or_trait_item(intr.clone(),
-                                                    cdata,
-                                                    did.index,
-                                                    tcx);
+            let trait_item = get_impl_or_trait_item(cdata, did.index, tcx);
             if let Some(ty::MethodTraitItem(ref method)) = trait_item {
                 Some((*method).clone())
             } else {
@@ -1095,10 +1062,7 @@ pub fn get_provided_trait_methods<'a, 'tcx>(intr: Rc<IdentInterner>,
     }).collect()
 }
 
-pub fn get_associated_consts<'a, 'tcx>(intr: Rc<IdentInterner>,
-                                       cdata: Cmd,
-                                       id: DefIndex,
-                                       tcx: TyCtxt<'a, 'tcx, 'tcx>)
+pub fn get_associated_consts<'a, 'tcx>(cdata: Cmd, id: DefIndex, tcx: TyCtxt<'a, 'tcx, 'tcx>)
                                        -> Vec<Rc<ty::AssociatedConst<'tcx>>> {
     let item = cdata.lookup_item(id);
 
@@ -1109,10 +1073,7 @@ pub fn get_associated_consts<'a, 'tcx>(intr: Rc<IdentInterner>,
 
             match item_sort(ac_doc) {
                 Some('C') | Some('c') => {
-                    let trait_item = get_impl_or_trait_item(intr.clone(),
-                                                            cdata,
-                                                            did.index,
-                                                            tcx);
+                    let trait_item = get_impl_or_trait_item(cdata, did.index, tcx);
                     if let Some(ty::ConstTraitItem(ref ac)) = trait_item {
                         Some((*ac).clone())
                     } else {
@@ -1180,14 +1141,13 @@ fn struct_field_family_to_visibility(family: Family) -> ty::Visibility {
     }
 }
 
-pub fn get_struct_field_names(intr: &IdentInterner, cdata: Cmd, id: DefIndex)
-    -> Vec<ast::Name> {
+pub fn get_struct_field_names(cdata: Cmd, id: DefIndex) -> Vec<ast::Name> {
     let item = cdata.lookup_item(id);
     let mut index = 0;
     reader::tagged_docs(item, tag_item_field).map(|an_item| {
-        item_name(intr, an_item)
+        item_name(an_item)
     }).chain(reader::tagged_docs(item, tag_item_unnamed_field).map(|_| {
-        let name = intr.intern(&index.to_string());
+        let name = token::with_ident_interner(|interner| interner.intern(index.to_string()));
         index += 1;
         name
     })).collect()
@@ -1503,12 +1463,12 @@ pub fn get_plugin_registrar_fn(data: &[u8]) -> Option<DefIndex> {
         .map(|doc| DefIndex::from_u32(reader::doc_as_u32(doc)))
 }
 
-pub fn each_exported_macro<F>(data: &[u8], intr: &IdentInterner, mut f: F) where
+pub fn each_exported_macro<F>(data: &[u8], mut f: F) where
     F: FnMut(ast::Name, Vec<ast::Attribute>, Span, String) -> bool,
 {
     let macros = reader::get_doc(rbml::Doc::new(data), tag_macro_defs);
     for macro_doc in reader::tagged_docs(macros, tag_macro_def) {
-        let name = item_name(intr, macro_doc);
+        let name = item_name(macro_doc);
         let attrs = get_attributes(macro_doc);
         let span = get_macro_span(macro_doc);
         let body = reader::get_doc(macro_doc, tag_macro_def_body);
diff --git a/src/librustc_trans/debuginfo/metadata.rs b/src/librustc_trans/debuginfo/metadata.rs
index b84cc028d0c..46813d957dc 100644
--- a/src/librustc_trans/debuginfo/metadata.rs
+++ b/src/librustc_trans/debuginfo/metadata.rs
@@ -81,7 +81,7 @@ pub struct UniqueTypeId(ast::Name);
 // UniqueTypeIds.
 pub struct TypeMap<'tcx> {
     // The UniqueTypeIds created so far
-    unique_id_interner: Interner<Rc<String>>,
+    unique_id_interner: Interner,
     // A map from UniqueTypeId to debuginfo metadata for that type. This is a 1:1 mapping.
     unique_id_to_metadata: FnvHashMap<UniqueTypeId, DIType>,
     // A map from types to debuginfo metadata. This is a N:1 mapping.
@@ -313,7 +313,7 @@ impl<'tcx> TypeMap<'tcx> {
         // Trim to size before storing permanently
         unique_type_id.shrink_to_fit();
 
-        let key = self.unique_id_interner.intern(Rc::new(unique_type_id));
+        let key = self.unique_id_interner.intern(unique_type_id);
         self.type_to_unique_id.insert(type_, UniqueTypeId(key));
 
         return UniqueTypeId(key);
@@ -383,7 +383,7 @@ impl<'tcx> TypeMap<'tcx> {
         let enum_variant_type_id = format!("{}::{}",
                                            &self.get_unique_type_id_as_string(enum_type_id),
                                            variant_name);
-        let interner_key = self.unique_id_interner.intern(Rc::new(enum_variant_type_id));
+        let interner_key = self.unique_id_interner.intern(enum_variant_type_id);
         UniqueTypeId(interner_key)
     }
 }
diff --git a/src/librustc_trans/trans_item.rs b/src/librustc_trans/trans_item.rs
index d3271e6d44c..8b8e658533e 100644
--- a/src/librustc_trans/trans_item.rs
+++ b/src/librustc_trans/trans_item.rs
@@ -32,7 +32,6 @@ use rustc::dep_graph::DepNode;
 use std::hash::{Hash, Hasher};
 use syntax::ast::{self, NodeId};
 use syntax::{attr,errors};
-use syntax::parse::token;
 use type_of;
 use glue;
 use abi::{Abi, FnType};
@@ -605,8 +604,8 @@ fn push_type_params<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     for projection in projections {
         let projection = projection.skip_binder();
-        let name = token::get_ident_interner().get(projection.projection_ty.item_name);
-        output.push_str(&name[..]);
+        let name = &projection.projection_ty.item_name.as_str();
+        output.push_str(name);
         output.push_str("=");
         push_unique_type_name(tcx, projection.ty, output);
         output.push_str(", ");
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 85ea94e02e8..49a3991ecbe 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -24,7 +24,6 @@ use rustc_metadata::cstore::CStore;
 
 use syntax::{ast, codemap};
 use syntax::feature_gate::UnstableFeatures;
-use syntax::parse::token;
 use errors;
 use errors::emitter::ColorConfig;
 
@@ -136,7 +135,7 @@ pub fn run_core(search_paths: SearchPaths,
 
     let dep_graph = DepGraph::new(false);
     let _ignore = dep_graph.in_ignore();
-    let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+    let cstore = Rc::new(CStore::new(&dep_graph));
     let sess = session::build_session_(sessopts, &dep_graph, cpath, diagnostic_handler,
                                        codemap, cstore.clone());
     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index e3bc8037d13..bb69ba6e568 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -37,7 +37,6 @@ use rustc_resolve::MakeGlobMap;
 use syntax::codemap::CodeMap;
 use errors;
 use errors::emitter::ColorConfig;
-use syntax::parse::token;
 
 use core;
 use clean;
@@ -82,7 +81,7 @@ pub fn run(input: &str,
 
     let dep_graph = DepGraph::new(false);
     let _ignore = dep_graph.in_ignore();
-    let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+    let cstore = Rc::new(CStore::new(&dep_graph));
     let sess = session::build_session_(sessopts,
                                        &dep_graph,
                                        Some(input_path.clone()),
@@ -239,7 +238,7 @@ fn runtest(test: &str, cratename: &str, cfgs: Vec<String>, libs: SearchPaths,
     let diagnostic_handler = errors::Handler::with_emitter(true, false, box emitter);
 
     let dep_graph = DepGraph::new(false);
-    let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+    let cstore = Rc::new(CStore::new(&dep_graph));
     let sess = session::build_session_(sessopts,
                                        &dep_graph,
                                        None,
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index c6374e59c1b..4656ba03e21 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -259,7 +259,6 @@ pub struct Parser<'a> {
     pub restrictions: Restrictions,
     pub quote_depth: usize, // not (yet) related to the quasiquoter
     pub reader: Box<Reader+'a>,
-    pub interner: Rc<token::IdentInterner>,
     /// The set of seen errors about obsolete syntax. Used to suppress
     /// extra detail when the same error is seen twice
     pub obsolete_set: HashSet<ObsoleteSyntax>,
@@ -356,7 +355,6 @@ impl<'a> Parser<'a> {
 
         Parser {
             reader: rdr,
-            interner: token::get_ident_interner(),
             sess: sess,
             cfg: cfg,
             token: tok0.tok,
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index 8376d28164d..ab7ed223bb3 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -17,11 +17,11 @@ pub use self::Token::*;
 use ast::{self, BinOpKind};
 use ext::mtwt;
 use ptr::P;
-use util::interner::{RcStr, StrInterner};
-use util::interner;
+use util::interner::Interner;
 use tokenstream;
 
 use serialize::{Decodable, Decoder, Encodable, Encoder};
+use std::cell::RefCell;
 use std::fmt;
 use std::ops::Deref;
 use std::rc::Rc;
@@ -397,7 +397,7 @@ macro_rules! declare_keywords {(
     }
 
     fn mk_fresh_ident_interner() -> IdentInterner {
-        interner::StrInterner::prefill(&[$($string,)*])
+        Interner::prefill(&[$($string,)*])
     }
 }}
 
@@ -473,22 +473,25 @@ declare_keywords! {
 }
 
 // looks like we can get rid of this completely...
-pub type IdentInterner = StrInterner;
+pub type IdentInterner = Interner;
 
 // if an interner exists in TLS, return it. Otherwise, prepare a
 // fresh one.
 // FIXME(eddyb) #8726 This should probably use a thread-local reference.
-pub fn get_ident_interner() -> Rc<IdentInterner> {
-    thread_local!(static KEY: Rc<::parse::token::IdentInterner> = {
-        Rc::new(mk_fresh_ident_interner())
+pub fn with_ident_interner<T, F: FnOnce(&mut IdentInterner) -> T>(f: F) -> T {
+    thread_local!(static KEY: RefCell<IdentInterner> = {
+        RefCell::new(mk_fresh_ident_interner())
     });
-    KEY.with(|k| k.clone())
+    KEY.with(|interner| f(&mut *interner.borrow_mut()))
 }
 
 /// Reset the ident interner to its initial state.
 pub fn reset_ident_interner() {
-    let interner = get_ident_interner();
-    interner.reset(mk_fresh_ident_interner());
+    with_ident_interner(|interner| *interner = mk_fresh_ident_interner());
+}
+
+pub fn clear_ident_interner() {
+    with_ident_interner(|interner| *interner = IdentInterner::new());
 }
 
 /// Represents a string stored in the thread-local interner. Because the
@@ -502,19 +505,19 @@ pub fn reset_ident_interner() {
 /// somehow.
 #[derive(Clone, PartialEq, Hash, PartialOrd, Eq, Ord)]
 pub struct InternedString {
-    string: RcStr,
+    string: Rc<String>,
 }
 
 impl InternedString {
     #[inline]
     pub fn new(string: &'static str) -> InternedString {
         InternedString {
-            string: RcStr::new(string),
+            string: Rc::new(string.to_owned()),
         }
     }
 
     #[inline]
-    fn new_from_rc_str(string: RcStr) -> InternedString {
+    fn new_from_rc_str(string: Rc<String>) -> InternedString {
         InternedString {
             string: string,
         }
@@ -522,8 +525,7 @@ impl InternedString {
 
     #[inline]
     pub fn new_from_name(name: ast::Name) -> InternedString {
-        let interner = get_ident_interner();
-        InternedString::new_from_rc_str(interner.get(name))
+        with_ident_interner(|interner| InternedString::new_from_rc_str(interner.get(name)))
     }
 }
 
@@ -611,13 +613,13 @@ pub fn intern_and_get_ident(s: &str) -> InternedString {
 /// Maps a string to its interned representation.
 #[inline]
 pub fn intern(s: &str) -> ast::Name {
-    get_ident_interner().intern(s)
+    with_ident_interner(|interner| interner.intern(s))
 }
 
 /// gensym's a new usize, using the current interner.
 #[inline]
 pub fn gensym(s: &str) -> ast::Name {
-    get_ident_interner().gensym(s)
+    with_ident_interner(|interner| interner.gensym(s))
 }
 
 /// Maps a string to an identifier with an empty syntax context.
@@ -636,8 +638,7 @@ pub fn gensym_ident(s: &str) -> ast::Ident {
 // note that this guarantees that str_ptr_eq(ident_to_string(src),interner_get(fresh_name(src)));
 // that is, that the new name and the old one are connected to ptr_eq strings.
 pub fn fresh_name(src: ast::Ident) -> ast::Name {
-    let interner = get_ident_interner();
-    interner.gensym_copy(src.name)
+    with_ident_interner(|interner| interner.gensym_copy(src.name))
     // following: debug version. Could work in final except that it's incompatible with
     // good error messages and uses of struct names in ambiguous could-be-binding
     // locations. Also definitely destroys the guarantee given above about ptr_eq.
diff --git a/src/libsyntax/util/interner.rs b/src/libsyntax/util/interner.rs
index 7295b36af0f..6bb409715aa 100644
--- a/src/libsyntax/util/interner.rs
+++ b/src/libsyntax/util/interner.rs
@@ -15,212 +15,72 @@
 use ast::Name;
 
 use std::borrow::Borrow;
-use std::cell::RefCell;
-use std::cmp::Ordering;
 use std::collections::HashMap;
-use std::fmt;
-use std::hash::Hash;
-use std::ops::Deref;
 use std::rc::Rc;
 
-pub struct Interner<T> {
-    map: RefCell<HashMap<T, Name>>,
-    vect: RefCell<Vec<T> >,
-}
-
-// when traits can extend traits, we should extend index<Name,T> to get []
-impl<T: Eq + Hash + Clone + 'static> Interner<T> {
-    pub fn new() -> Interner<T> {
-        Interner {
-            map: RefCell::new(HashMap::new()),
-            vect: RefCell::new(Vec::new()),
-        }
-    }
-
-    pub fn prefill(init: &[T]) -> Interner<T> {
-        let rv = Interner::new();
-        for v in init {
-            rv.intern((*v).clone());
-        }
-        rv
-    }
-
-    pub fn intern(&self, val: T) -> Name {
-        let mut map = self.map.borrow_mut();
-        if let Some(&idx) = (*map).get(&val) {
-            return idx;
-        }
-
-        let mut vect = self.vect.borrow_mut();
-        let new_idx = Name((*vect).len() as u32);
-        (*map).insert(val.clone(), new_idx);
-        (*vect).push(val);
-        new_idx
-    }
-
-    pub fn gensym(&self, val: T) -> Name {
-        let mut vect = self.vect.borrow_mut();
-        let new_idx = Name((*vect).len() as u32);
-        // leave out of .map to avoid colliding
-        (*vect).push(val);
-        new_idx
-    }
-
-    pub fn get(&self, idx: Name) -> T {
-        let vect = self.vect.borrow();
-        (*vect)[idx.0 as usize].clone()
-    }
-
-    pub fn len(&self) -> usize {
-        let vect = self.vect.borrow();
-        (*vect).len()
-    }
-
-    pub fn find<Q: ?Sized>(&self, val: &Q) -> Option<Name>
-    where T: Borrow<Q>, Q: Eq + Hash {
-        let map = self.map.borrow();
-        match (*map).get(val) {
-            Some(v) => Some(*v),
-            None => None,
-        }
-    }
-
-    pub fn clear(&self) {
-        *self.map.borrow_mut() = HashMap::new();
-        *self.vect.borrow_mut() = Vec::new();
-    }
-}
-
-#[derive(Clone, PartialEq, Hash, PartialOrd)]
-pub struct RcStr {
-    string: Rc<String>,
-}
-
-impl RcStr {
-    pub fn new(string: &str) -> RcStr {
-        RcStr {
-            string: Rc::new(string.to_string()),
-        }
-    }
-}
-
-impl Eq for RcStr {}
-
-impl Ord for RcStr {
-    fn cmp(&self, other: &RcStr) -> Ordering {
-        self[..].cmp(&other[..])
-    }
-}
-
-impl fmt::Debug for RcStr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self[..].fmt(f)
-    }
-}
-
-impl fmt::Display for RcStr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self[..].fmt(f)
-    }
-}
+#[derive(PartialEq, Eq, Hash)]
+struct RcStr(Rc<String>);
 
 impl Borrow<str> for RcStr {
     fn borrow(&self) -> &str {
-        &self.string[..]
+        &self.0
     }
 }
 
-impl Deref for RcStr {
-    type Target = str;
-
-    fn deref(&self) -> &str { &self.string[..] }
-}
-
-/// A StrInterner differs from Interner<String> in that it accepts
-/// &str rather than RcStr, resulting in less allocation.
-pub struct StrInterner {
-    map: RefCell<HashMap<RcStr, Name>>,
-    vect: RefCell<Vec<RcStr> >,
+#[derive(Default)]
+pub struct Interner {
+    names: HashMap<RcStr, Name>,
+    strings: Vec<Rc<String>>,
 }
 
 /// When traits can extend traits, we should extend index<Name,T> to get []
-impl StrInterner {
-    pub fn new() -> StrInterner {
-        StrInterner {
-            map: RefCell::new(HashMap::new()),
-            vect: RefCell::new(Vec::new()),
-        }
+impl Interner {
+    pub fn new() -> Self {
+        Interner::default()
     }
 
-    pub fn prefill(init: &[&str]) -> StrInterner {
-        let rv = StrInterner::new();
-        for &v in init { rv.intern(v); }
-        rv
-    }
-
-    pub fn intern(&self, val: &str) -> Name {
-        let mut map = self.map.borrow_mut();
-        if let Some(&idx) = map.get(val) {
-            return idx;
+    pub fn prefill(init: &[&str]) -> Self {
+        let mut this = Interner::new();
+        for &string in init {
+            this.intern(string);
         }
-
-        let new_idx = Name(self.len() as u32);
-        let val = RcStr::new(val);
-        map.insert(val.clone(), new_idx);
-        self.vect.borrow_mut().push(val);
-        new_idx
-    }
-
-    pub fn gensym(&self, val: &str) -> Name {
-        let new_idx = Name(self.len() as u32);
-        // leave out of .map to avoid colliding
-        self.vect.borrow_mut().push(RcStr::new(val));
-        new_idx
+        this
     }
 
-    // I want these gensyms to share name pointers
-    // with existing entries. This would be automatic,
-    // except that the existing gensym creates its
-    // own managed ptr using to_managed. I think that
-    // adding this utility function is the most
-    // lightweight way to get what I want, though not
-    // necessarily the cleanest.
-
-    /// Create a gensym with the same name as an existing
-    /// entry.
-    pub fn gensym_copy(&self, idx : Name) -> Name {
-        let new_idx = Name(self.len() as u32);
-        // leave out of map to avoid colliding
-        let mut vect = self.vect.borrow_mut();
-        let existing = (*vect)[idx.0 as usize].clone();
-        vect.push(existing);
-        new_idx
-    }
+    pub fn intern<T: Borrow<str> + Into<String>>(&mut self, string: T) -> Name {
+        if let Some(&name) = self.names.get(string.borrow()) {
+            return name;
+        }
 
-    pub fn get(&self, idx: Name) -> RcStr {
-        (*self.vect.borrow())[idx.0 as usize].clone()
+        let name = Name(self.strings.len() as u32);
+        let string = Rc::new(string.into());
+        self.strings.push(string.clone());
+        self.names.insert(RcStr(string), name);
+        name
     }
 
-    pub fn len(&self) -> usize {
-        self.vect.borrow().len()
+    pub fn gensym(&mut self, string: &str) -> Name {
+        let gensym = Name(self.strings.len() as u32);
+        // leave out of `names` to avoid colliding
+        self.strings.push(Rc::new(string.to_owned()));
+        gensym
     }
 
-    pub fn find<Q: ?Sized>(&self, val: &Q) -> Option<Name>
-    where RcStr: Borrow<Q>, Q: Eq + Hash {
-        match (*self.map.borrow()).get(val) {
-            Some(v) => Some(*v),
-            None => None,
-        }
+    /// Create a gensym with the same name as an existing entry.
+    pub fn gensym_copy(&mut self, name: Name) -> Name {
+        let gensym = Name(self.strings.len() as u32);
+        // leave out of `names` to avoid colliding
+        let string = self.strings[name.0 as usize].clone();
+        self.strings.push(string);
+        gensym
     }
 
-    pub fn clear(&self) {
-        *self.map.borrow_mut() = HashMap::new();
-        *self.vect.borrow_mut() = Vec::new();
+    pub fn get(&self, name: Name) -> Rc<String> {
+        self.strings[name.0 as usize].clone()
     }
 
-    pub fn reset(&self, other: StrInterner) {
-        *self.map.borrow_mut() = other.map.into_inner();
-        *self.vect.borrow_mut() = other.vect.into_inner();
+    pub fn find(&self, string: &str) -> Option<Name> {
+        self.names.get(string).cloned()
     }
 }
 
@@ -230,53 +90,8 @@ mod tests {
     use ast::Name;
 
     #[test]
-    #[should_panic]
-    fn i1 () {
-        let i : Interner<RcStr> = Interner::new();
-        i.get(Name(13));
-    }
-
-    #[test]
-    fn interner_tests () {
-        let i : Interner<RcStr> = Interner::new();
-        // first one is zero:
-        assert_eq!(i.intern(RcStr::new("dog")), Name(0));
-        // re-use gets the same entry:
-        assert_eq!(i.intern(RcStr::new("dog")), Name(0));
-        // different string gets a different #:
-        assert_eq!(i.intern(RcStr::new("cat")), Name(1));
-        assert_eq!(i.intern(RcStr::new("cat")), Name(1));
-        // dog is still at zero
-        assert_eq!(i.intern(RcStr::new("dog")), Name(0));
-        // gensym gets 3
-        assert_eq!(i.gensym(RcStr::new("zebra") ), Name(2));
-        // gensym of same string gets new number :
-        assert_eq!(i.gensym (RcStr::new("zebra") ), Name(3));
-        // gensym of *existing* string gets new number:
-        assert_eq!(i.gensym(RcStr::new("dog")), Name(4));
-        assert_eq!(i.get(Name(0)), RcStr::new("dog"));
-        assert_eq!(i.get(Name(1)), RcStr::new("cat"));
-        assert_eq!(i.get(Name(2)), RcStr::new("zebra"));
-        assert_eq!(i.get(Name(3)), RcStr::new("zebra"));
-        assert_eq!(i.get(Name(4)), RcStr::new("dog"));
-    }
-
-    #[test]
-    fn i3 () {
-        let i : Interner<RcStr> = Interner::prefill(&[
-            RcStr::new("Alan"),
-            RcStr::new("Bob"),
-            RcStr::new("Carol")
-        ]);
-        assert_eq!(i.get(Name(0)), RcStr::new("Alan"));
-        assert_eq!(i.get(Name(1)), RcStr::new("Bob"));
-        assert_eq!(i.get(Name(2)), RcStr::new("Carol"));
-        assert_eq!(i.intern(RcStr::new("Bob")), Name(1));
-    }
-
-    #[test]
-    fn string_interner_tests() {
-        let i : StrInterner = StrInterner::new();
+    fn interner_tests() {
+        let mut i: Interner = Interner::new();
         // first one is zero:
         assert_eq!(i.intern("dog"), Name(0));
         // re-use gets the same entry:
@@ -294,13 +109,13 @@ mod tests {
         assert_eq!(i.gensym("dog"), Name(4));
         // gensym tests again with gensym_copy:
         assert_eq!(i.gensym_copy(Name(2)), Name(5));
-        assert_eq!(i.get(Name(5)), RcStr::new("zebra"));
+        assert_eq!(*i.get(Name(5)), "zebra");
         assert_eq!(i.gensym_copy(Name(2)), Name(6));
-        assert_eq!(i.get(Name(6)), RcStr::new("zebra"));
-        assert_eq!(i.get(Name(0)), RcStr::new("dog"));
-        assert_eq!(i.get(Name(1)), RcStr::new("cat"));
-        assert_eq!(i.get(Name(2)), RcStr::new("zebra"));
-        assert_eq!(i.get(Name(3)), RcStr::new("zebra"));
-        assert_eq!(i.get(Name(4)), RcStr::new("dog"));
+        assert_eq!(*i.get(Name(6)), "zebra");
+        assert_eq!(*i.get(Name(0)), "dog");
+        assert_eq!(*i.get(Name(1)), "cat");
+        assert_eq!(*i.get(Name(2)), "zebra");
+        assert_eq!(*i.get(Name(3)), "zebra");
+        assert_eq!(*i.get(Name(4)), "dog");
     }
 }
diff --git a/src/test/run-make/execution-engine/test.rs b/src/test/run-make/execution-engine/test.rs
index 21e1463b6ef..2e90b518432 100644
--- a/src/test/run-make/execution-engine/test.rs
+++ b/src/test/run-make/execution-engine/test.rs
@@ -30,18 +30,16 @@ use std::thread::Builder;
 
 use rustc::dep_graph::DepGraph;
 use rustc::hir::map as ast_map;
-use rustc::middle::cstore::{CrateStore, LinkagePreference};
+use rustc::middle::cstore::LinkagePreference;
 use rustc::ty;
 use rustc::session::config::{self, basic_options, build_configuration, Input, Options};
 use rustc::session::build_session;
 use rustc_driver::{driver, abort_on_err};
 use rustc_resolve::MakeGlobMap;
-use rustc_metadata::creader::read_local_crates;
 use rustc_metadata::cstore::CStore;
 use libc::c_void;
 
 use rustc_errors::registry::Registry;
-use syntax::parse::token;
 
 fn main() {
     // Currently trips an assertion on i686-msvc, presumably because the support
@@ -226,7 +224,7 @@ fn compile_program(input: &str, sysroot: PathBuf)
     let handle = thread.spawn(move || {
         let opts = build_exec_options(sysroot);
         let dep_graph = DepGraph::new(opts.build_dep_graph());
-        let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+        let cstore = Rc::new(CStore::new(&dep_graph));
         let sess = build_session(opts,
                                  &dep_graph,
                                  None,
diff --git a/src/test/run-make/issue-19371/foo.rs b/src/test/run-make/issue-19371/foo.rs
index aa3495ec5ee..d5220316a20 100644
--- a/src/test/run-make/issue-19371/foo.rs
+++ b/src/test/run-make/issue-19371/foo.rs
@@ -23,7 +23,6 @@ use rustc::session::config::{basic_options, build_configuration, Input, OutputTy
 use rustc_driver::driver::{compile_input, CompileController, anon_src};
 use rustc_metadata::cstore::CStore;
 use rustc_errors::registry::Registry;
-use syntax::parse::token;
 
 use std::path::PathBuf;
 use std::rc::Rc;
@@ -57,7 +56,7 @@ fn basic_sess(sysroot: PathBuf) -> (Session, Rc<CStore>) {
 
     let descriptions = Registry::new(&rustc::DIAGNOSTICS);
     let dep_graph = DepGraph::new(opts.build_dep_graph());
-    let cstore = Rc::new(CStore::new(&dep_graph, token::get_ident_interner()));
+    let cstore = Rc::new(CStore::new(&dep_graph));
     let sess = build_session(opts, &dep_graph, None, descriptions, cstore.clone());
     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
     (sess, cstore)