From 9ac468b841cf01e7b575f4c20d10df8096c31f7a Mon Sep 17 00:00:00 2001
From: Ms2ger <Ms2ger@gmail.com>
Date: Tue, 10 May 2016 15:34:25 +0200
Subject: [PATCH 1/5] Store a reference rather than a RefCell in
 LocalCrateReader.

---
 src/librustc_driver/driver.rs              | 2 +-
 src/librustc_driver/test.rs                | 2 +-
 src/librustc_metadata/creader.rs           | 9 ++++-----
 src/librustdoc/core.rs                     | 2 +-
 src/test/run-make/execution-engine/test.rs | 2 +-
 5 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index e72204e5e22de..8841480f7f644 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -148,7 +148,7 @@ pub fn compile_input(sess: &Session,
 
         time(sess.time_passes(),
              "external crate/lib resolution",
-             || LocalCrateReader::new(sess, &cstore, defs, &expanded_crate, &id)
+             || LocalCrateReader::new(sess, &cstore, &defs.borrow(), &expanded_crate, &id)
                     .read_crates(&dep_graph));
 
         time(sess.time_passes(),
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index 869bbb723ef41..ed9a092b6ff2f 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -121,7 +121,7 @@ fn test_env<F>(source_string: &str,
     let dep_graph = DepGraph::new(false);
     let krate = driver::assign_node_ids(&sess, krate);
     let defs = &RefCell::new(hir_map::collect_definitions(&krate));
-    LocalCrateReader::new(&sess, &cstore, defs, &krate, "test_crate").read_crates(&dep_graph);
+    LocalCrateReader::new(&sess, &cstore, &defs.borrow(), &krate, "test_crate").read_crates(&dep_graph);
     let _ignore = dep_graph.in_ignore();
 
     let (_, resolutions, mut hir_forest) = {
diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index 190e8552d199a..2b02a745bef74 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -46,7 +46,7 @@ pub struct LocalCrateReader<'a> {
     cstore: &'a CStore,
     creader: CrateReader<'a>,
     krate: &'a ast::Crate,
-    defintions: &'a RefCell<hir_map::Definitions>,
+    defintions: &'a hir_map::Definitions,
 }
 
 pub struct CrateReader<'a> {
@@ -843,7 +843,7 @@ impl<'a> CrateReader<'a> {
 impl<'a> LocalCrateReader<'a> {
     pub fn new(sess: &'a Session,
                cstore: &'a CStore,
-               defs: &'a RefCell<hir_map::Definitions>,
+               defs: &'a hir_map::Definitions,
                krate: &'a ast::Crate,
                local_crate_name: &str)
                -> LocalCrateReader<'a> {
@@ -902,9 +902,8 @@ impl<'a> LocalCrateReader<'a> {
                                                                       PathKind::Crate,
                                                                       true);
 
-                        let defs = self.defintions.borrow();
-                        let def_id = defs.opt_local_def_id(i.id).unwrap();
-                        let len = defs.def_path(def_id.index).data.len();
+                        let def_id = self.defintions.opt_local_def_id(i.id).unwrap();
+                        let len = self.defintions.def_path(def_id.index).data.len();
 
                         self.creader.update_extern_crate(cnum,
                                                          ExternCrate {
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index e5fc84037ce57..77a780805a695 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -154,7 +154,7 @@ pub fn run_core(search_paths: SearchPaths,
     let dep_graph = DepGraph::new(false);
 
     let defs = &RefCell::new(hir_map::collect_definitions(&krate));
-    LocalCrateReader::new(&sess, &cstore, &defs, &krate, &name).read_crates(&dep_graph);
+    LocalCrateReader::new(&sess, &cstore, &defs.borrow(), &krate, &name).read_crates(&dep_graph);
 
     // Lower ast -> hir and resolve.
     let (analysis, resolutions, mut hir_forest) = {
diff --git a/src/test/run-make/execution-engine/test.rs b/src/test/run-make/execution-engine/test.rs
index 98412c08df520..f46846c34a5ef 100644
--- a/src/test/run-make/execution-engine/test.rs
+++ b/src/test/run-make/execution-engine/test.rs
@@ -241,7 +241,7 @@ fn compile_program(input: &str, sysroot: PathBuf)
         let dep_graph = DepGraph::new(sess.opts.build_dep_graph());
         let krate = driver::assign_node_ids(&sess, krate);
         let defs = RefCell::new(ast_map::collect_definitions(&krate));
-        LocalCrateReader::new(&sess, &cstore, &defs, &krate, &id).read_crates(&dep_graph);
+        LocalCrateReader::new(&sess, &cstore, &defs.borrow(), &krate, &id).read_crates(&dep_graph);
         let (analysis, resolutions, mut hir_forest) = {
             let defs = &mut *defs.borrow_mut();
             driver::lower_and_resolve(&sess, &id, defs, &krate, dep_graph, MakeGlobMap::No)

From 8d3531d3db513bd71ad1ac041ad9a2172ec34012 Mon Sep 17 00:00:00 2001
From: Ms2ger <Ms2ger@gmail.com>
Date: Tue, 10 May 2016 15:36:50 +0200
Subject: [PATCH 2/5] Correct typo in LocalCrateReader::definitions.

---
 src/librustc_metadata/creader.rs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index 2b02a745bef74..62c208dbcb2a4 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -46,7 +46,7 @@ pub struct LocalCrateReader<'a> {
     cstore: &'a CStore,
     creader: CrateReader<'a>,
     krate: &'a ast::Crate,
-    defintions: &'a hir_map::Definitions,
+    definitions: &'a hir_map::Definitions,
 }
 
 pub struct CrateReader<'a> {
@@ -852,7 +852,7 @@ impl<'a> LocalCrateReader<'a> {
             cstore: cstore,
             creader: CrateReader::new(sess, cstore, local_crate_name),
             krate: krate,
-            defintions: defs,
+            definitions: defs,
         }
     }
 
@@ -902,8 +902,8 @@ impl<'a> LocalCrateReader<'a> {
                                                                       PathKind::Crate,
                                                                       true);
 
-                        let def_id = self.defintions.opt_local_def_id(i.id).unwrap();
-                        let len = self.defintions.def_path(def_id.index).data.len();
+                        let def_id = self.definitions.opt_local_def_id(i.id).unwrap();
+                        let len = self.definitions.def_path(def_id.index).data.len();
 
                         self.creader.update_extern_crate(cnum,
                                                          ExternCrate {

From e919f251800b792e15b3c72cdfb19e539cd74971 Mon Sep 17 00:00:00 2001
From: Ms2ger <Ms2ger@gmail.com>
Date: Tue, 10 May 2016 15:34:52 +0200
Subject: [PATCH 3/5] Delay wrapping Definitions into a RefCell around
 LocalCrateReader.

---
 src/librustc_driver/driver.rs              | 13 +++++++------
 src/librustc_driver/test.rs                |  9 +++++----
 src/librustdoc/core.rs                     |  9 +++++----
 src/test/run-make/execution-engine/test.rs | 11 ++++++-----
 4 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index 8841480f7f644..3f9fa0a23c2d8 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -142,13 +142,13 @@ pub fn compile_input(sess: &Session,
         let dep_graph = DepGraph::new(sess.opts.build_dep_graph());
 
         // Collect defintions for def ids.
-        let defs = &RefCell::new(time(sess.time_passes(),
-                                 "collecting defs",
-                                 || hir_map::collect_definitions(&expanded_crate)));
+        let mut defs = time(sess.time_passes(),
+                            "collecting defs",
+                            || hir_map::collect_definitions(&expanded_crate));
 
         time(sess.time_passes(),
              "external crate/lib resolution",
-             || LocalCrateReader::new(sess, &cstore, &defs.borrow(), &expanded_crate, &id)
+             || LocalCrateReader::new(sess, &cstore, &defs, &expanded_crate, &id)
                     .read_crates(&dep_graph));
 
         time(sess.time_passes(),
@@ -156,8 +156,8 @@ pub fn compile_input(sess: &Session,
              || lint::check_ast_crate(sess, &expanded_crate));
 
         let (analysis, resolutions, mut hir_forest) = {
-            let defs = &mut *defs.borrow_mut();
-            lower_and_resolve(sess, &id, defs, &expanded_crate, dep_graph, control.make_glob_map)
+            lower_and_resolve(sess, &id, &mut defs, &expanded_crate, dep_graph,
+                              control.make_glob_map)
         };
 
         // Discard MTWT tables that aren't required past lowering to HIR.
@@ -165,6 +165,7 @@ pub fn compile_input(sess: &Session,
             syntax::ext::mtwt::clear_tables();
         }
 
+        let defs = &RefCell::new(defs);
         let arenas = ty::CtxtArenas::new();
 
         // Construct the HIR map
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index ed9a092b6ff2f..59713c66afcb6 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -120,15 +120,16 @@ fn test_env<F>(source_string: &str,
 
     let dep_graph = DepGraph::new(false);
     let krate = driver::assign_node_ids(&sess, krate);
-    let defs = &RefCell::new(hir_map::collect_definitions(&krate));
-    LocalCrateReader::new(&sess, &cstore, &defs.borrow(), &krate, "test_crate").read_crates(&dep_graph);
+    let mut defs = hir_map::collect_definitions(&krate);
+    LocalCrateReader::new(&sess, &cstore, &defs, &krate, "test_crate").read_crates(&dep_graph);
     let _ignore = dep_graph.in_ignore();
 
     let (_, resolutions, mut hir_forest) = {
-        let (defs, dep_graph) = (&mut *defs.borrow_mut(), dep_graph.clone());
-        driver::lower_and_resolve(&sess, "test-crate", defs, &krate, dep_graph, MakeGlobMap::No)
+        driver::lower_and_resolve(&sess, "test-crate", &mut defs, &krate, dep_graph.clone(),
+                                  MakeGlobMap::No)
     };
 
+    let defs = &RefCell::new(defs);
     let arenas = ty::CtxtArenas::new();
     let ast_map = hir_map::map_crate(&mut hir_forest, defs);
 
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 77a780805a695..857a1176f496a 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -153,15 +153,16 @@ pub fn run_core(search_paths: SearchPaths,
     let krate = driver::assign_node_ids(&sess, krate);
     let dep_graph = DepGraph::new(false);
 
-    let defs = &RefCell::new(hir_map::collect_definitions(&krate));
-    LocalCrateReader::new(&sess, &cstore, &defs.borrow(), &krate, &name).read_crates(&dep_graph);
+    let mut defs = hir_map::collect_definitions(&krate);
+    LocalCrateReader::new(&sess, &cstore, &defs, &krate, &name).read_crates(&dep_graph);
 
     // Lower ast -> hir and resolve.
     let (analysis, resolutions, mut hir_forest) = {
-        let defs = &mut *defs.borrow_mut();
-        driver::lower_and_resolve(&sess, &name, defs, &krate, dep_graph, resolve::MakeGlobMap::No)
+        driver::lower_and_resolve(&sess, &name, &mut defs, &krate, dep_graph,
+                                  resolve::MakeGlobMap::No)
     };
 
+    let defs = &RefCell::new(defs);
     let arenas = ty::CtxtArenas::new();
     let hir_map = hir_map::map_crate(&mut hir_forest, defs);
 
diff --git a/src/test/run-make/execution-engine/test.rs b/src/test/run-make/execution-engine/test.rs
index f46846c34a5ef..0d10f31556644 100644
--- a/src/test/run-make/execution-engine/test.rs
+++ b/src/test/run-make/execution-engine/test.rs
@@ -240,14 +240,15 @@ fn compile_program(input: &str, sysroot: PathBuf)
 
         let dep_graph = DepGraph::new(sess.opts.build_dep_graph());
         let krate = driver::assign_node_ids(&sess, krate);
-        let defs = RefCell::new(ast_map::collect_definitions(&krate));
-        LocalCrateReader::new(&sess, &cstore, &defs.borrow(), &krate, &id).read_crates(&dep_graph);
+        let mut defs = ast_map::collect_definitions(&krate);
+        LocalCrateReader::new(&sess, &cstore, &defs, &krate, &id).read_crates(&dep_graph);
         let (analysis, resolutions, mut hir_forest) = {
-            let defs = &mut *defs.borrow_mut();
-            driver::lower_and_resolve(&sess, &id, defs, &krate, dep_graph, MakeGlobMap::No)
+            driver::lower_and_resolve(&sess, &id, &mut defs, &krate, dep_graph, MakeGlobMap::No)
         };
+
+        let defs = &RefCell::new(defs);
         let arenas = ty::CtxtArenas::new();
-        let ast_map = ast_map::map_crate(&mut hir_forest, &defs);
+        let ast_map = ast_map::map_crate(&mut hir_forest, defs);
 
         abort_on_err(driver::phase_3_run_analysis_passes(
             &sess, ast_map, analysis, resolutions, &arenas, &id,

From 5511e6568f41b7ca9d57b0055c193be187e437d8 Mon Sep 17 00:00:00 2001
From: Ms2ger <Ms2ger@gmail.com>
Date: Tue, 10 May 2016 15:43:51 +0200
Subject: [PATCH 4/5] Hand ownership of the Definitions to map_crate.

---
 src/librustc/hir/map/mod.rs                | 6 +++---
 src/librustc_driver/driver.rs              | 1 -
 src/librustc_driver/test.rs                | 2 --
 src/librustdoc/core.rs                     | 1 -
 src/librustdoc/test.rs                     | 2 +-
 src/test/run-make/execution-engine/test.rs | 2 --
 6 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/src/librustc/hir/map/mod.rs b/src/librustc/hir/map/mod.rs
index 92f8c9249c842..f0eb580cfd57e 100644
--- a/src/librustc/hir/map/mod.rs
+++ b/src/librustc/hir/map/mod.rs
@@ -196,7 +196,7 @@ pub struct Map<'ast> {
     /// plain old integers.
     map: RefCell<Vec<MapEntry<'ast>>>,
 
-    definitions: &'ast RefCell<Definitions>,
+    definitions: RefCell<Definitions>,
 }
 
 impl<'ast> Map<'ast> {
@@ -790,7 +790,7 @@ pub fn collect_definitions<'ast>(krate: &'ast ast::Crate) -> Definitions {
 }
 
 pub fn map_crate<'ast>(forest: &'ast mut Forest,
-                       definitions: &'ast RefCell<Definitions>)
+                       definitions: Definitions)
                        -> Map<'ast> {
     let mut collector = NodeCollector::root(&forest.krate);
     intravisit::walk_crate(&mut collector, &forest.krate);
@@ -816,7 +816,7 @@ pub fn map_crate<'ast>(forest: &'ast mut Forest,
         forest: forest,
         dep_graph: forest.dep_graph.clone(),
         map: RefCell::new(map),
-        definitions: definitions,
+        definitions: RefCell::new(definitions),
     }
 }
 
diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index 3f9fa0a23c2d8..a979410ca94de 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -165,7 +165,6 @@ pub fn compile_input(sess: &Session,
             syntax::ext::mtwt::clear_tables();
         }
 
-        let defs = &RefCell::new(defs);
         let arenas = ty::CtxtArenas::new();
 
         // Construct the HIR map
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index 59713c66afcb6..270376bda766e 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -29,7 +29,6 @@ use rustc_metadata::cstore::CStore;
 use rustc_metadata::creader::LocalCrateReader;
 use rustc::hir::map as hir_map;
 use rustc::session::{self, config};
-use std::cell::RefCell;
 use std::rc::Rc;
 use syntax::ast;
 use syntax::abi::Abi;
@@ -129,7 +128,6 @@ fn test_env<F>(source_string: &str,
                                   MakeGlobMap::No)
     };
 
-    let defs = &RefCell::new(defs);
     let arenas = ty::CtxtArenas::new();
     let ast_map = hir_map::map_crate(&mut hir_forest, defs);
 
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 857a1176f496a..e5919a4b35ff6 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -162,7 +162,6 @@ pub fn run_core(search_paths: SearchPaths,
                                   resolve::MakeGlobMap::No)
     };
 
-    let defs = &RefCell::new(defs);
     let arenas = ty::CtxtArenas::new();
     let hir_map = hir_map::map_crate(&mut hir_forest, defs);
 
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index fc548924e2964..c57452b6e2fc3 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -95,7 +95,7 @@ pub fn run(input: &str,
         .expect("phase_2_configure_and_expand aborted in rustdoc!");
     let krate = driver::assign_node_ids(&sess, krate);
     let dep_graph = DepGraph::new(false);
-    let defs = &RefCell::new(hir_map::collect_definitions(&krate));
+    let defs = hir_map::collect_definitions(&krate);
 
     let mut dummy_resolver = DummyResolver;
     let lcx = LoweringContext::new(&sess, Some(&krate), &mut dummy_resolver);
diff --git a/src/test/run-make/execution-engine/test.rs b/src/test/run-make/execution-engine/test.rs
index 0d10f31556644..a2893fa2f0dc0 100644
--- a/src/test/run-make/execution-engine/test.rs
+++ b/src/test/run-make/execution-engine/test.rs
@@ -20,7 +20,6 @@ extern crate rustc_metadata;
 extern crate rustc_resolve;
 #[macro_use] extern crate syntax;
 
-use std::cell::RefCell;
 use std::ffi::{CStr, CString};
 use std::mem::transmute;
 use std::path::PathBuf;
@@ -246,7 +245,6 @@ fn compile_program(input: &str, sysroot: PathBuf)
             driver::lower_and_resolve(&sess, &id, &mut defs, &krate, dep_graph, MakeGlobMap::No)
         };
 
-        let defs = &RefCell::new(defs);
         let arenas = ty::CtxtArenas::new();
         let ast_map = ast_map::map_crate(&mut hir_forest, defs);
 

From c0e321abcbc25c47e55a808628fb7e65b3fe0f98 Mon Sep 17 00:00:00 2001
From: Ms2ger <Ms2ger@gmail.com>
Date: Tue, 10 May 2016 15:52:33 +0200
Subject: [PATCH 5/5] Make LocalCrateReader private to creader.

---
 src/librustc_driver/driver.rs              |  5 ++--
 src/librustc_driver/test.rs                |  4 ++--
 src/librustc_metadata/creader.rs           | 27 +++++++++++++++-------
 src/librustdoc/core.rs                     |  4 ++--
 src/test/run-make/execution-engine/test.rs |  4 ++--
 5 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index a979410ca94de..d2a5e12009ec4 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -28,7 +28,7 @@ use rustc_borrowck as borrowck;
 use rustc_incremental;
 use rustc_resolve as resolve;
 use rustc_metadata::macro_import;
-use rustc_metadata::creader::LocalCrateReader;
+use rustc_metadata::creader::read_local_crates;
 use rustc_metadata::cstore::CStore;
 use rustc_trans::back::link;
 use rustc_trans::back::write;
@@ -148,8 +148,7 @@ pub fn compile_input(sess: &Session,
 
         time(sess.time_passes(),
              "external crate/lib resolution",
-             || LocalCrateReader::new(sess, &cstore, &defs, &expanded_crate, &id)
-                    .read_crates(&dep_graph));
+             || read_local_crates(sess, &cstore, &defs, &expanded_crate, &id, &dep_graph));
 
         time(sess.time_passes(),
              "early lint checks",
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index 270376bda766e..5c62d236844ee 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -26,7 +26,7 @@ use rustc::traits::ProjectionMode;
 use rustc::ty::{self, Ty, TyCtxt, TypeFoldable};
 use rustc::infer::{self, InferOk, InferResult, TypeOrigin};
 use rustc_metadata::cstore::CStore;
-use rustc_metadata::creader::LocalCrateReader;
+use rustc_metadata::creader::read_local_crates;
 use rustc::hir::map as hir_map;
 use rustc::session::{self, config};
 use std::rc::Rc;
@@ -120,7 +120,7 @@ fn test_env<F>(source_string: &str,
     let dep_graph = DepGraph::new(false);
     let krate = driver::assign_node_ids(&sess, krate);
     let mut defs = hir_map::collect_definitions(&krate);
-    LocalCrateReader::new(&sess, &cstore, &defs, &krate, "test_crate").read_crates(&dep_graph);
+    read_local_crates(&sess, &cstore, &defs, &krate, "test_crate", &dep_graph);
     let _ignore = dep_graph.in_ignore();
 
     let (_, resolutions, mut hir_forest) = {
diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index 62c208dbcb2a4..63c6af704bbfe 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -41,7 +41,7 @@ use syntax::parse::token::InternedString;
 use syntax::visit;
 use log;
 
-pub struct LocalCrateReader<'a> {
+struct LocalCrateReader<'a> {
     sess: &'a Session,
     cstore: &'a CStore,
     creader: CrateReader<'a>,
@@ -841,12 +841,12 @@ impl<'a> CrateReader<'a> {
 }
 
 impl<'a> LocalCrateReader<'a> {
-    pub fn new(sess: &'a Session,
-               cstore: &'a CStore,
-               defs: &'a hir_map::Definitions,
-               krate: &'a ast::Crate,
-               local_crate_name: &str)
-               -> LocalCrateReader<'a> {
+    fn new(sess: &'a Session,
+           cstore: &'a CStore,
+           defs: &'a hir_map::Definitions,
+           krate: &'a ast::Crate,
+           local_crate_name: &str)
+           -> LocalCrateReader<'a> {
         LocalCrateReader {
             sess: sess,
             cstore: cstore,
@@ -859,7 +859,7 @@ impl<'a> LocalCrateReader<'a> {
     // Traverses an AST, reading all the information about use'd crates and
     // extern libraries necessary for later resolving, typechecking, linking,
     // etc.
-    pub fn read_crates(&mut self, dep_graph: &DepGraph) {
+    fn read_crates(&mut self, dep_graph: &DepGraph) {
         let _task = dep_graph.in_task(DepNode::CrateReader);
 
         self.process_crate(self.krate);
@@ -981,6 +981,17 @@ impl<'a> LocalCrateReader<'a> {
     }
 }
 
+/// Traverses an AST, reading all the information about use'd crates and extern
+/// libraries necessary for later resolving, typechecking, linking, etc.
+pub fn read_local_crates(sess: & Session,
+                         cstore: & CStore,
+                         defs: & hir_map::Definitions,
+                         krate: & ast::Crate,
+                         local_crate_name: &str,
+                         dep_graph: &DepGraph) {
+    LocalCrateReader::new(sess, cstore, defs, krate, local_crate_name).read_crates(dep_graph)
+}
+
 /// Imports the codemap from an external crate into the codemap of the crate
 /// currently being compiled (the "local crate").
 ///
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index e5919a4b35ff6..67eb268af08f6 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -21,7 +21,7 @@ use rustc::lint;
 use rustc_trans::back::link;
 use rustc_resolve as resolve;
 use rustc_metadata::cstore::CStore;
-use rustc_metadata::creader::LocalCrateReader;
+use rustc_metadata::creader::read_local_crates;
 
 use syntax::{ast, codemap, errors};
 use syntax::errors::emitter::ColorConfig;
@@ -154,7 +154,7 @@ pub fn run_core(search_paths: SearchPaths,
     let dep_graph = DepGraph::new(false);
 
     let mut defs = hir_map::collect_definitions(&krate);
-    LocalCrateReader::new(&sess, &cstore, &defs, &krate, &name).read_crates(&dep_graph);
+    read_local_crates(&sess, &cstore, &defs, &krate, &name, &dep_graph);
 
     // Lower ast -> hir and resolve.
     let (analysis, resolutions, mut hir_forest) = {
diff --git a/src/test/run-make/execution-engine/test.rs b/src/test/run-make/execution-engine/test.rs
index a2893fa2f0dc0..0ad113b8d8b38 100644
--- a/src/test/run-make/execution-engine/test.rs
+++ b/src/test/run-make/execution-engine/test.rs
@@ -34,7 +34,7 @@ use rustc::session::config::{self, basic_options, build_configuration, Input, Op
 use rustc::session::build_session;
 use rustc_driver::{driver, abort_on_err};
 use rustc_resolve::MakeGlobMap;
-use rustc_metadata::creader::LocalCrateReader;
+use rustc_metadata::creader::read_local_crates;
 use rustc_metadata::cstore::CStore;
 use libc::c_void;
 
@@ -240,7 +240,7 @@ fn compile_program(input: &str, sysroot: PathBuf)
         let dep_graph = DepGraph::new(sess.opts.build_dep_graph());
         let krate = driver::assign_node_ids(&sess, krate);
         let mut defs = ast_map::collect_definitions(&krate);
-        LocalCrateReader::new(&sess, &cstore, &defs, &krate, &id).read_crates(&dep_graph);
+        read_local_crates(&sess, &cstore, &defs, &krate, &id, &dep_graph);
         let (analysis, resolutions, mut hir_forest) = {
             driver::lower_and_resolve(&sess, &id, &mut defs, &krate, dep_graph, MakeGlobMap::No)
         };