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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: AI12-0218:  What is the portable representation clause for
 processing IETF packets on little-endian machines?
Date: Fri, 11 May 2018 17:14:25 -0500
Organization: JSA Research & Innovation
Message-ID: <pd54k2$ut7$2@franka.jacob-sparre.dk>
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Date: 2018-05-11T17:14:25-05:00
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"Paul Rubin" <no.email@nospam.invalid> wrote in message 
news:87po23yusb.fsf@nightsong.com...
>...
> That particularly means if the hardware happens to be little-endian and
> you want to add x and y together with a 32-bit "add" machine
> instruction, you are requiring the compiler to generate code that reads
> x and y from memory and performs byte swaps before doing the addition.

Yes, that's precisely what AI12-0218-1 is intended to require, and  also 
explains why there is so much resistance to it. Ada to-date has adopted 
rules that do not require byte-swapping although it does require supporting 
the non-native big-endianness.

                           Randy.