Re: Packing, Ordering, and Rearranging

Article View: comp.std.c++

Article #397

#397

From: Roland McGrath
Date: Mon, 20 Aug 1990 23:31

30 lines
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In article <1233@lupine.NCD.COM> rfg@NCD.COM (Ron Guilmette) writes:

   You can definitely specify what you want the exact layout of a struct to be
   in C and have it be obeyed and have it be portable.  People do it all the
   time.  Now if only this were possible in C++. :-(

Since this newsgroup is about the standard for C++, I'll assume you are talking
about standard-conforming implementations of C as well.  In this context, your
assertion is patently false.  Given the definition:

struct
  {
    int elt0;
    int elt1;
  } foo;

any of the following layouts are entirely permissable within standard C:

0:	elt0
4:	elt1

0:	elt0
8:	elt1

0:	elt0
1000000:elt1
--
	Roland McGrath
	Free Software Foundation, Inc.
roland@ai.mit.edu, uunet!ai.mit.edu!roland

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From: roland@ai.mit.edu (Roland McGrath)
Newsgroups: comp.std.c++
Subject: Re: Packing, Ordering, and Rearranging
Message-ID: <ROLAND.90Aug20193125@wookumz.ai.mit.edu>
Date: 20 Aug 90 23:31:25 GMT
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