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Groups > comp.lang.c > #107596
| From | Robert Wessel <robertwessel2@yahoo.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: struct padding question |
| Message-ID | <llsvdc55d0d8etsi9mlkfl6s7o01d16gr7@4ax.com> (permalink) |
| References | <ob062g$coi$1@dont-email.me> <ob07qd$if0$1@dont-email.me> <obon1p$4aj$1@dont-email.me> |
| Organization | Forte - www.forteinc.com |
| Date | 2017-04-01 13:46 -0500 |
On Sat, 1 Apr 2017 19:15:25 +0200, Noob <root@127.0.0.1> wrote:
>On 23/03/2017 11:28, David Brown wrote:
>
>> struct data {
>> uint64_t ctr[6]; // 8-byte alignment, 8x6 data
>> long double mean; // 16-byte alignment, 16-byte data
>> long double variance; // 16-byte alignment, 16-byte data
>> long double * p_ptr; // 8-byte alignment, 8-byte data
>>
>> // inserted by compiler...
>> uint64_t padding; // 8-byte alignment, 8-byte data
>> };
>
>I think some platforms have sizeof(long double) = 10?
>(I have x86 in mind, with the 80-bit FP numbers.)
There have been implementations of, 10-byte (80-bit), x86 long double
which have 2, 4, 8 and 16 byte alignment requirements.
For example, amongst compilers actually supporting the 80-bit type, MS
and Borland's 16-bit compilers use 2-byte alignment, several 32-bit
(typical x86 GCC, for example) compilers use 4B alignment, Watcom uses
8B in both 16 and 32-bit versions, and most *nix compilers on 64B use
16B alignment, as does ICC on Windows in both 32 and 64B modes).
*Not* intended to be an exhaustive list.
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struct padding question MehdiAmini <atorrses@gmail.com> - 2017-03-23 14:28 +0430
Re: struct padding question David Brown <david.brown@hesbynett.no> - 2017-03-23 11:28 +0100
Re: struct padding question MehdiAmini <atorrses@gmail.com> - 2017-03-23 16:44 +0430
Re: struct padding question jm.bourguet@gmail.com - 2017-03-23 05:30 -0700
Re: struct padding question Keith Thompson <kst-u@mib.org> - 2017-03-23 08:45 -0700
Re: struct padding question Noob <root@127.0.0.1> - 2017-04-01 19:15 +0200
Re: struct padding question tim prince <n8tm@aol.com> - 2017-04-01 14:41 -0400
Re: struct padding question supercat@casperkitty.com - 2017-04-02 09:15 -0700
Re: struct padding question scott@slp53.sl.home (Scott Lurndal) - 2017-04-03 13:51 +0000
Re: struct padding question supercat@casperkitty.com - 2017-04-03 07:48 -0700
Re: struct padding question scott@slp53.sl.home (Scott Lurndal) - 2017-04-03 15:47 +0000
Re: struct padding question supercat@casperkitty.com - 2017-04-03 09:24 -0700
Re: struct padding question Keith Thompson <kst-u@mib.org> - 2017-04-01 11:43 -0700
Re: struct padding question Robert Wessel <robertwessel2@yahoo.com> - 2017-04-01 13:46 -0500
Re: struct padding question Keith Thompson <kst-u@mib.org> - 2017-04-01 12:00 -0700
Re: struct padding question Robert Wessel <robertwessel2@yahoo.com> - 2017-04-01 16:40 -0500
Re: struct padding question Keith Thompson <kst-u@mib.org> - 2017-04-01 15:24 -0700
Re: struct padding question Robert Wessel <robertwessel2@yahoo.com> - 2017-04-03 17:46 -0500
Re: struct padding question BartC <bc@freeuk.com> - 2017-03-23 11:50 +0000
Re: struct padding question David Brown <david.brown@hesbynett.no> - 2017-03-23 14:08 +0100
Re: struct padding question BartC <bc@freeuk.com> - 2017-03-23 13:31 +0000
Re: struct padding question David Brown <david.brown@hesbynett.no> - 2017-03-23 14:46 +0100
Re: struct padding question BartC <bc@freeuk.com> - 2017-03-23 14:07 +0000
Re: struct padding question David Brown <david.brown@hesbynett.no> - 2017-03-23 15:52 +0100
Re: struct padding question scott@slp53.sl.home (Scott Lurndal) - 2017-03-23 17:19 +0000
Re: struct padding question David Brown <david.brown@hesbynett.no> - 2017-03-23 19:57 +0100
Re: struct padding question Ian Pilcher <arequipeno@gmail.com> - 2017-03-23 08:52 -0500
Re: struct padding question David Brown <david.brown@hesbynett.no> - 2017-03-23 15:54 +0100
Re: struct padding question supercat@casperkitty.com - 2017-03-23 08:29 -0700
Re: struct padding question GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-23 14:04 +0100
Re: struct padding question MehdiAmini <atorrses@gmail.com> - 2017-03-23 20:32 +0430
Re: struct padding question GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-23 18:35 +0100
Re: struct padding question supercat@casperkitty.com - 2017-03-23 12:02 -0700
Re: struct padding question Keith Thompson <kst-u@mib.org> - 2017-03-23 12:21 -0700
Re: struct padding question supercat@casperkitty.com - 2017-03-23 12:55 -0700
Re: struct padding question Les Cargill <lcargill99@comcast.com> - 2017-03-25 15:12 -0500
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