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Date:	Fri, 08 Feb 2002 11:43:59 +0200
From:	"Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
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In-reply-to:	<3C639073.4D12303@yahoo.com> (message from CBFalconer on Fri, 08
	Feb 2002 08:49:31 GMT)
Subject:	Re: Alignment problem
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> From: CBFalconer <cbfalconer AT yahoo DOT com>
> Newsgroups: comp.os.msdos.djgpp
> Date: Fri, 08 Feb 2002 08:49:31 GMT
> 
> Of course you can do whatever you want on a cast to int.  I'm not
> complaining about that.  I'm just pointing out that it is
> undefined behaviour as far as the language is concerned.

The language standard (at least C99) does require malloc to return a
pointer that is suitably aligned for the types of object for which the
pointer could be used.  In practice, for x86 CPUs, this means that any
object that is 8 bytes or larger needs to be aligned on 8-byte
boundary.

> On many systems, including segmented DOS, that cast would make no
> sense whatsoever.

I believe the purpose of the cast was to use the pointer in an
arithmetic expression (bitwise AND), that's all.

> So the test of the integer representation really says
> nothing about the alignment, except in particular implementations.

Right.  But I believe the OP _was_ discussing a particular
implementation: the DJGPP implementation of malloc.

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