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From: dewar@gnat.com (Robert Dewar)
Newsgroups: comp.lang.ada
Subject: Re: 64bit access to an array of 8bit values
Date: 4 Mar 2002 02:29:49 -0800
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"John R. Strohm" <strohm@airmail.net> wrote in message news:<0CFB5EECF8614F8D.52C8F36A468D2F14.3AD3D533D2B72FDB@lp.airnews.net>...

> The short answer is that you can't do what you want to 
> do.

short, but wrong :-)

> 
> The Ada compiler is not required to allocate precisely 
> one byte per array element, 

Well you can perfectly well use

  for x'component_size use 8;

to enforce that

> and it probably didn't.

Yes, of course it did
  
> Instead, it will probably allocate one
> "word" per array element,

No, of course it won't

> because word access is probably faster than byte
> access.

Not on any machine the questioner is likely to be using. 
This post sure had a lot of misinformation. Have not seen
yet whether there is anything useful in the rest of the
posts. The previous post about storage pools was even 
more irrelevant. The right answer of course is to use
unchecked conversion, and you can quite easily do what
you want. There is nothing wrong with pointer conversion
when it makes sense.