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From: CBFalconer <cbfalconer AT yahoo DOT com>
Organization: Ched Research
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Subject: Re: Alignment problem
References: <3C629769 DOT AEAFB611 AT cyberoptics DOT com> <3C62A89A DOT 9DF630C5 AT yahoo DOT com> <3C630FB1 DOT E69F87A AT cyberoptics DOT com> <3C63319A DOT 2E193983 AT yahoo DOT com> <7484-Fri08Feb2002094855+0200-eliz AT is DOT elta DOT co DOT il>
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Date: Fri, 08 Feb 2002 08:49:31 GMT
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Eli Zaretskii wrote:
> 
> > From: CBFalconer <cbfalconer AT yahoo DOT com>
> >
... snip ...
> 
> >      printf(" ptr %p is %2d-byte aligned. (int)p = %d6\n",
> 
> So my conclusion is that pointers are 8-byte aligned both before and
> after the cast, for the program you wrote.
> 
> > 0x205d8 * 10 + 6 = 1325686, for example.
> 
> What does this example supposed to show?

Nothing in particular - it was just a recast of the OPs code. 
However I see that a totally extraneous 6 slipped into the format
string, which explains everything.

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. On many
systems, including segmented DOS, that cast would make no sense
whatsoever.  So the test of the integer representation really says
nothing about the alignment, except in particular implementations.

-- 
Chuck F (cbfalconer AT yahoo DOT com) (cbfalconer AT XXXXworldnet DOT att DOT net)
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