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[Caml-list] NULL as a caml value
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Date: 2002-05-13 (09:05)
From: Christopher Quinn <cq@h...>
Subject: Re: [Caml-list] NULL as a caml value
Jacques Garrigue wrote:
> From: Lauri Alanko <>
>>The docs weren't very clear on this, so I just wanted to check: is
>>(value)NULL a legal caml value? Checking from the sources, it seems that the
>>GC does leave alone all pointers that don't point to within the caml-managed
>>heap. However, the docs state that only "memory allocated by malloc" can be
>>turned directly into an abstract caml value. So may I rely on NULL working?
>>It would ease dealing with many C interfaces.
> Yes, NULL is valid, as are all word-aligned addresses outside of the
> Caml heap.

Does it even need to be word aligned?
If Is_long() tests positive the 'pointer' is also ignored.
I hope I have not erred!?

- chris

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