GPR#560: add test.

testsuite/tests/lib-obj/Makefile

@@ -0,0 +1,21 @@
+#**************************************************************************
+#*                                                                        *
+#*                                OCaml                                   *
+#*                                                                        *
+#*                 Xavier Clerc, SED, INRIA Rocquencourt                  *
+#*                                                                        *
+#*   Copyright 2010 Institut National de Recherche en Informatique et     *
+#*     en Automatique.                                                    *
+#*                                                                        *
+#*   All rights reserved.  This file is distributed under the terms of    *
+#*   the GNU Lesser General Public License version 2.1, with the          *
+#*   special exception on linking described in the file LICENSE.          *
+#*                                                                        *
+#**************************************************************************
+
+BASEDIR=../..
+MODULES=
+MAIN_MODULE=reachable_words
+
+include $(BASEDIR)/makefiles/Makefile.one
+include $(BASEDIR)/makefiles/Makefile.common

testsuite/tests/lib-obj/reachable_words.ml

@@ -0,0 +1,50 @@
+(**************************************************************************)
+(*                                                                        *)
+(*                                OCaml                                   *)
+(*                                                                        *)
+(*                            Daniel C. Buenzli                           *)
+(*                                                                        *)
+(*   Copyright 2015 Institut National de Recherche en Informatique et     *)
+(*     en Automatique.                                                    *)
+(*                                                                        *)
+(*   All rights reserved.  This file is distributed under the terms of    *)
+(*   the GNU Lesser General Public License version 2.1, with the          *)
+(*   special exception on linking described in the file LICENSE.          *)
+(*                                                                        *)
+(**************************************************************************)
+
+
+let native =
+  match Filename.basename Sys.argv.(0) with
+  | "program.byte" | "program.byte.exe" -> false
+  | "program.native" | "program.native.exe" -> true
+  | s -> print_endline s; assert false
+
+
+let size x = Obj.reachable_words (Obj.repr x)
+
+let expect_size s x =
+  let i = size x in
+  if i <> s then
+    Printf.printf "size = %i; expected = %i\n%!" i s
+
+type t =
+  | A of int
+  | B of t * t
+
+let () =
+  let x = Random.int 10 in
+  expect_size 0 42;
+  expect_size (if native then 0 else 3) (1, 2);
+  expect_size 2 [| x |];
+  expect_size 3 [| x; 0 |];
+
+  let a = A x in
+  expect_size 2 a;
+  expect_size 5 (B (a, a)); (* sharing *)
+  expect_size 7 (B (a, A (x + 1)));
+
+  let rec b = B (a, b) in (* cycle *)
+  expect_size 5 b;
+
+  print_endline "OK"

testsuite/tests/lib-obj/reachable_words.reference

@@ -0,0 +1 @@
+OK