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From: Jacob Sparre Andersen <jacob@jacob-sparre.dk>
Newsgroups: comp.lang.ada
Subject: X'Alignment and System.Address without a "mod" operator?
Date: Mon, 05 Jan 2015 15:49:16 +0100
Organization: Jacob Sparre Andersen Research & Innovation
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Date: 2015-01-05T15:49:16+01:00
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RM 13.3(23/2) says:

   The value of this attribute is of type universal_integer, and
   nonnegative; zero means that the object is not necessarily aligned on
   a storage element boundary. If X'Alignment is not zero, then X is
   aligned on a storage unit boundary and X'Address is an integral
   multiple of X'Alignment (that is, the Address modulo the Alignment is
   zero).

But when I look for a suitable function to check the requirement in the
final parenthesis in package System (RM 13.7) - something like:

   function "mod" (Left : Address; Right : some_integer_type)
     return some_integer_type;

it isn't there.  That makes it kind of hard to implement storage pools
for types with alignment requirements.

I suppose I should report the problem to Ada-Comment, but I would prefer
that somebody could tell me that I have overlooked something.

Greetings,

Jacob
-- 
"If I have to choose between two evils, I choose the one I
 haven't tried before."