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From: "J-P. Rosen" <rosen@adalog.fr>
Newsgroups: comp.lang.ada
Subject: Re: Question about package Interfaces.
Date: Tue, 14 Sep 2010 19:01:33 +0200
Organization: Adalog
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Date: 2010-09-14T19:01:33+02:00
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Le 14/09/2010 18:36, Jeffrey Carter a �crit :
> On 09/13/2010 11:33 PM, J-P. Rosen wrote:
>>
>> Imagine that you declared:
>> X : Unsigned_8;
>> and you discover that the declaration advances the data counter by 4
>> bytes. You can interpret that as X occupying 32 bits, or as X occupying
>> only 8 bits with 3 unused padding bytes ahead of it.
>>
>> There is positively no way to tell the difference.
> 
> You could examine the machine code to see if it does 4-byte or 1-byte
> load and stores.
> 
Not exactly.
A compiler is allowed to overwrite unused bytes if it makes code more
efficient


-- 
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           J-P. Rosen (rosen@adalog.fr)
Visit Adalog's web site at http://www.adalog.fr