First lame stab at solving the diamond import problem

2 files changed, 31 insertions, 20 deletions

diff --git a/src/boot/driver/lib.ml b/src/boot/driver/lib.ml
index 40d79256754..3b3ee72d700 100644
--- a/src/boot/driver/lib.ml
+++ b/src/boot/driver/lib.ml
@@ -125,6 +125,7 @@ let get_mod
     (use_id:node_id)
     (nref:node_id ref)
     (oref:opaque_id ref)
+    (crate_item_cache:(crate_id, Ast.mod_items) Hashtbl.t)
     : (filename * Ast.mod_items) =
   let found = Queue.create () in
   let suffix =
@@ -183,22 +184,24 @@ let get_mod
                   (file_matches file)
                 then
                   begin
-                    iflog sess
-                      begin
-                        fun _ ->
-                          log sess "matched against library %s" file;
-                          match get_meta sess file with
-                              None -> ()
-                            | Some meta ->
-                                if not (Hashtbl.mem
-                                    sess.Session.sess_crate_meta meta) then
-                                  Hashtbl.add sess.Session.sess_crate_meta
-                                    meta (Session.make_crate_id sess);
-                                Array.iter
-                                  (fun (k,v) -> log sess "%s = %S" k v)
-                                  meta;
-                      end;
-                    Queue.add file found;
+                    log sess "matched against library %s" file;
+
+                    let meta = get_meta sess file in
+                    let crate_id =
+                      match meta with
+                          None -> Session.make_crate_id sess
+                        | Some meta ->
+                            iflog sess begin fun _ ->
+                              Array.iter
+                                (fun (k, v) -> log sess "%s = %S" k v)
+                                meta
+                            end;
+                            htab_search_or_default
+                              sess.Session.sess_crate_meta
+                              meta
+                              (fun () -> Session.make_crate_id sess)
+                    in
+                    Queue.add (file, crate_id) found;
                   end;
                 scan()
             with
@@ -210,8 +213,11 @@ let get_mod
     match Queue.length found with
         0 -> Common.err (Some use_id) "unsatisfied 'use' clause"
       | 1 ->
-          let filename = Queue.pop found in
-          let items = get_file_mod sess abi filename nref oref in
+          let (filename, crate_id) = Queue.pop found in
+          let items =
+            htab_search_or_default crate_item_cache crate_id
+              (fun () -> get_file_mod sess abi filename nref oref)
+          in
             (filename, items)
       | _ -> Common.err (Some use_id) "multiple crates match 'use' clause"
 ;;
diff --git a/src/boot/driver/main.ml b/src/boot/driver/main.ml
index 199a372954d..1e4c28e834e 100644
--- a/src/boot/driver/main.ml
+++ b/src/boot/driver/main.ml
@@ -239,7 +239,9 @@ let _ =
 ;;
 
 
-let parse_input_crate _ : Ast.crate =
+let parse_input_crate
+    (crate_cache:(crate_id, Ast.mod_items) Hashtbl.t)
+    : Ast.crate =
   Session.time_inner "parse" sess
     begin
       fun _ ->
@@ -250,12 +252,14 @@ let parse_input_crate _ : Ast.crate =
             Cexp.parse_crate_file sess
               (Lib.get_mod sess abi)
               (Lib.infer_lib_name sess)
+              crate_cache
           else
             if Filename.check_suffix infile ".rs"
             then
               Cexp.parse_src_file sess
                 (Lib.get_mod sess abi)
                 (Lib.infer_lib_name sess)
+                crate_cache
             else
               begin
                 Printf.fprintf stderr
@@ -295,7 +299,8 @@ let parse_input_crate _ : Ast.crate =
 
 let (crate:Ast.crate) =
   try
-    parse_input_crate()
+    let crate_cache = Hashtbl.create 1 in
+    parse_input_crate crate_cache
   with
       Not_implemented (ido, str) ->
         Session.report_err sess ido str;