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To: Markus Mottl <mottl@miss.wu-wien.ac.at>
Cc: Nicolas Joliot <Nicolas.Joliot@irisa.fr>, caml-list@inria.fr
Subject: Re: =?iso-8859-1?q?Interfa=E7age?= C/CAML
References: <3992D2D9.906E0BA7@irisa.fr>
	<20000810191404.A21178@miss.wu-wien.ac.at>
From: David.Mentre@irisa.fr (David=?iso-8859-1?q?_Mentr=E9?=)
Date: 11 Aug 2000 10:58:47 +0200
In-Reply-To: Markus Mottl's message of "Thu, 10 Aug 2000 19:14:04 +0200"
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Markus Mottl <mottl@miss.wu-wien.ac.at> writes:

> It seems that a common bug has struck again: using "Store_{whatever}" in
> C-interfaces is only allowed (and then mandatory) with structured blocks.
> Using it for anything else may crash the GC.

I would say that Store_{whatever} macros are useful for data structures
that are created in the C-world but should be managed (and destroyed) in
the OCaml-world, WITHOUT any further access on the data by the C
part. For all other cases, use the Field_{whatever} macros. With this
macro, the OCaml GC won't try to have a look at your C data structures.

By the way, Markus has already found a bug like this in my own code. See
this message for further details on how the bug is triggered :
  http://caml.inria.fr/archives/200002/msg00074.html

I hope it helps,
d.
-- 
 David.Mentre@irisa.fr -- http://www.irisa.fr/prive/dmentre/
 Opinions expressed here are only mine.