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From: diamond@tkou02.enet.dec.com (diamond@tkovoa)
Newsgroups: comp.std.c++
Subject: Re: Randomly ordered fields !?!? (Was:
Message-ID: <1940@tkou02.enet.dec.com>
Date: 31 Aug 90 01:58:09 GMT
References: <1070@lupine.NCD.COM> <259400004@inmet>
Reply-To: diamond@tkou02.enet.dec.com (diamond@tkovoa)
Organization: Digital Equipment Corporation Japan , Tokyo
Lines: 25

In article <259400004@inmet> stt@inmet.inmet.com writes:

>Re: Allowing compilers to reorder fields "at will".
>... you lose
>interoperability between successive versions of
>the same compiler, let alone interoperability between
>different compilers.

You lose nothing, because you never had such interoperability.
In C, padding can change from one release to the next, or depending on
optimization level.  In Pascal, a compiler can decline to do packing.
If I'm not mistaken, in Ada, bit-numbering does not have to match the
intuitive (big-endian or little-endian) numbering.

>Having used a language without strict field ordering
>rules, I can testify that it is a nightmare.

Surely you have such nightmares in every language you have used.
Except maybe assembly.  In order to avoid such nightmares, you have to
impose additional quality-of-implementation restrictions on the choice
of implementations that you are willing to buy.

-- 
Norman Diamond, Nihon DEC       diamond@tkou02.enet.dec.com
We steer like a sports car:  I use opinions; the company uses the rack.