PR#1878

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@5873 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

1 files changed, 22 insertions, 3 deletions

diff --git a/byterun/obj.c b/byterun/obj.c
index 73572dceb..f6001fbc3 100644
--- a/byterun/obj.c
+++ b/byterun/obj.c
@@ -49,7 +49,13 @@ CAMLprim value obj_is_block(value arg)
 
 CAMLprim value obj_tag(value arg)
 {
-  return Val_int(Tag_val(arg));
+  if (Is_long (arg)){
+    return 1000;
+  }else if (Is_young (arg) || Is_in_heap (arg)){
+    return Val_int(Tag_val(arg));
+  }else{
+    return 1001;
+  }
 }
 
 CAMLprim value obj_set_tag (value arg, value new_tag)
@@ -140,11 +146,13 @@ CAMLprim value obj_truncate (value v, value newsize)
 }
 
 
-/* [lazy_is_forward] and [lazy_follow_forward] are used in stdlib/lazy.ml.
+/* The following functions are used in stdlib/lazy.ml.
    They are not written in O'Caml because they must be atomic with respect
    to the GC.
  */
 
+/* [lazy_is_forward] is obsolete.  Stays here to make bootstrapping
+   easier for patched versions of 3.07.  To be removed before 3.08. */
 CAMLprim value lazy_is_forward (value v)
 {
   return Val_bool (Is_block (v) && Tag_val (v) == Forward_tag);
@@ -152,9 +160,20 @@ CAMLprim value lazy_is_forward (value v)
 
 CAMLprim value lazy_follow_forward (value v)
 {
-  if (Is_block (v) && Tag_val (v) == Forward_tag){
+  if (Is_block (v) && (Is_young (v) || Is_in_heap (v))
+      && Tag_val (v) == Forward_tag){
     return Forward_val (v);
   }else{
     return v;
   }
 }
+
+CAMLprim value lazy_make_forward (value v)
+{
+  CAMLparam1 (v);
+  CAMLlocal1 (res);
+
+  res = alloc_small (1, Forward_tag);
+  Modify (&Field (res, 0), v);
+  CAMLreturn (res);
+}