I am trying to understand the behavior of the interactive OCAML system. If I
   repeatedly perform the following line:

       let x = Array.create 1000000 0.0;;

   then each subsequent execution should shadow the previous ones making them
   unreachable. Yet the GC never collects the old bindings, even after I
   manually perform Gc.full_major() or Gc.compact().  Why is this?

Some time ago I observed the same thing and asked the same question.
To see the answer, go to the archive of Caml mailing list and search
for the thread "What exactly can be GC'ed?"

- Ching Tsun

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  Ching-Tsun Chou                   E-mail: ctchou@mipos2.intel.com  
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