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Obj.dup crash ?
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Date: -- (:)
From: skaller <skaller@u...>
Subject: Re: [Caml-list] Obj.dup crash ?
On Thu, 2004-12-30 at 22:04, Nicolas Cannasse wrote:
> > Concerning Obj.dup, I guess it is never actually called when the block
> > has 0 fields. Actually, where is Obj.dup used except in
> > CamlinternalOO.copy ?  Quick look. It is used in the code generator:
> > for array constants of size > 4, and for record expressions { ... with
> > ... } that copy the original record and then modify it (but the empty
> > record is not a valid type !). So indeed, it seems that Obj.dup is never
> > called for 0 fields blocks. The implementation has dead code, but
> > it is not buggy ;-)
> 
> It's also used in ExtLib DynArray when copying an array ;)

Obj.dup (Obj.magic (Array.make 0 0)); Gc.major();;
Warning S: this expression should have type unit.
Segmentation fault

What's the representation of a 0 length Array?

The weird message is due to CVS ocaml 3.09+dev12.
Array.copy doesn't exhibit this fault.


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