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Date: Tue, 8 Jun 2010 20:22:26 +0200
Message-ID: <AANLkTikRe85mNn83G8zU6JCQzjj2VkRlQQN1DOy1146q@mail.gmail.com>
Subject: Re: [Caml-list] Converting variants with only constant constructors 
	to integers
From: Kaustuv Chaudhuri <kaustuv.chaudhuri@inria.fr>
To: Jacques Garrigue <garrigue@math.nagoya-u.ac.jp>
Cc: bluestorm <bluestorm.dylc@gmail.com>,
	caml-list caml-list <caml-list@yquem.inria.fr>
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X-Spam: no; 0.00; variants:01 constructors:01 integers:01 polymorphism:01 abstr:01 abstr:01 1.0:98 1.0:98 wrote:01 caml-list:01 heuristic:02 allocated:02 allocated:02 garrigue:03 garrigue:03 

On Tue, Jun 8, 2010 at 4:37 PM, Jacques Garrigue
<garrigue@math.nagoya-u.ac.jp> wrote:
> Of course intify can cause a segmentation fault!
>
> # let arr = Array.of_list [intify 1.0; 0];;
> Segmentation fault

This may be splitting hairs, but the reason that fails is that
Array.of_list's ad hoc polymorphism heuristic assumes that if the
first element of the list is allocated, then all elements are
allocated. Merely changing the order works.

  # Array.of_list [Obj.repr 0 ; Obj.repr 1.0] ;;
  - : Obj.t array = [|<abstr>; <abstr>|]

Which one of Obj.repr of Array.of_list to blame, if that's the right
word, is not that relevant to any code a sane person might write.

-- Kaustuv