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From: "Jeffrey R.Carter" <spam.jrcarter.not@spam.acm.org.not>
Newsgroups: comp.lang.ada
Subject: Re: Ada array contiguity.
Date: Sun, 19 Feb 2023 23:02:36 +0100
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On 2023-02-19 14:34, Rod Kay wrote:
> 
>     I've been told that Ada array elements are not guaranteed to be contiguous 
> unless the 'Convention C' aspect is applied.

The ARM says little about how the compiler represents objects in the absence of 
representation clauses. However, ARM 13.7(12) 
(http://www.ada-auth.org/standards/aarm12_w_tc1/html/AA-13-7-1.html#I5653) says, 
"Storage_Array represents a contiguous sequence of storage elements."

ARM 13.9(17/3) 
(http://www.ada-auth.org/standards/aarm12_w_tc1/html/AA-13-9.html#I5679) says 
that a compiler that supports Unchecked_Conversion should use a contiguous 
representation for certain constrained array subtypes.

Using convention Fortran should also ensure a contiguous representation, add can 
apply (unlike convention C) to multidimensional arrays.

-- 
Jeff Carter
"All citizens will be required to change their underwear
every half hour. Underwear will be worn on the outside,
so we can check."
Bananas
29