Detect OCaml version used for the ocaml bridge in the configure script.

Conflicts:
	configure.ml

configure.ml

@@ -138,7 +138,7 @@ let check_feature f p =
 	else (print "disabled\n"; false)
 
 let native =
-  check_feature "ocamlopt" (fun () -> command "ocamlfind ocamlopt") && !native
+  check_feature "ocamlopt" (fun () -> command "ocamlfind ocamlopt")
 
 let check_pkg p () =
   try
@@ -179,7 +179,17 @@ let add_icon = match Sys.os_type with
 
 let check_mliface dir =
 (*  Sys.file_exists (Filename.concat dir "typing/types.ml") *)
-  Sys.file_exists (Filename.concat dir "typing/types.ml")
+  List.for_all (fun f ->
+    Sys.file_exists (Filename.concat dir f))
+    [ "typing/types.ml"; "VERSION" ]
+
+let mliface_version dir =
+  let ic = open_in (Filename.concat dir "VERSION") in
+  let s = input_line ic in
+  close_in ic;
+  if s < "4" then "3.x"
+  else if s < "4.02" then "4.01"
+  else "4.02"
 
 let ocaml_stdlib () =
   if (Sys.command "ocamlc -where > ocaml_stdlib" <> 0) then
@@ -195,17 +205,19 @@ let make_absolute dir =
   then Filename.concat (Sys.getcwd ()) dir
   else dir
 
-let ml_interface =
+let ml_interface, mliface_version =
   let dir1 = !(List.assoc "mliface" vars) in
   let dirs = if dir1 = "" then [] else [ make_absolute dir1 ] in
   print "ocaml sources... ";
   let rec loop = function
     | [] ->
 	print "not found (the interface will not be built)\n";
-	None
+	None, ""
     | d::dirs ->
 	if check_mliface d then
-	  (print ("found: " ^ d ^ "\n"); Some d)
+          let version = mliface_version d in
+	  (print ("found: " ^ d ^ ", version " ^ version ^ "\n");
+           Some d, version)
 	else loop dirs
   in
   loop dirs
@@ -285,7 +297,7 @@ let () =
   fprintf out "# This file has been generated by the configure script\n";
   fprintf out "NATIVE=%b\n" native;
   (match ml_interface with
-    | Some d -> fprintf out "ML_INTERFACE=true\nOCAML_SRC=%s\n" d
+    | Some d -> fprintf out "ML_INTERFACE=true\nOCAML_SRC=%s\nML_INTERFACE_VERSION=%s\n" d mliface_version
     | None -> fprintf out "ML_INTERFACE=false\n");
   fprintf out "PXP=%b\n" pxp;
   fprintf out "EXPAT=%b\n" expat;