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Groups > comp.lang.c > #126599
| Subject | Re: C2 Aims to Modernize the C Language |
|---|---|
| Newsgroups | comp.lang.c |
| References | (6 earlier) <20180212000054.32bbfbfafa91930c5a09c41c@gmail.com> <uF5gC.811010$rE1.542238@fx14.am4> <20180212122916.ed1d64b3b64af5cd70bccb61@gmail.com> <ECfgC.773861$ba4.49431@fx24.am4> <p5s881$m5u$1@dont-email.me> |
| From | bartc <bc@freeuk.com> |
| Message-ID | <egigC.4$w26.3@fx47.am4> (permalink) |
| Organization | virginmedia.com |
| Date | 2018-02-12 15:19 +0000 |
On 12/02/2018 14:27, David Brown wrote:
> On 12/02/18 13:18, bartc wrote:
>> On 12/02/2018 11:29, GOTHIER Nathan wrote:
>>> On Mon, 12 Feb 2018 00:59:07 +0000
>>> bartc <bc@freeuk.com> wrote:
>
>>>
>>>> The symbols aren't the problem. It is because those symbols are C
>>>> functions whose interface is defined in C terms. /That's/ the problem.
>>>
>>> Wrong! There is no C function in ELF, only symbols corresponding to
>>> assembly labels (i.e. memory addresses).
>>
>> You keep saying this. But you don't just call a label:
>>
>> call printf
>>
>> There are arguments to be passed, and values to be returned. That
>> information is documented in C terms. The mechanics might be stipulated
>> by the platform, but before that, you need to understand what the
>> parameters are. And that's where C gets in the way.
>>
>
> The ABI specifies the way the arguments are passed and values returned.
> ABI's are not C specific - but C types are simple enough that they
> correspond directly to the sorts of data passed here. The fact the C
> standards don't give precise values for things like the size of "int" or
> the padding of structs is irrelevant - the ABI gives those details. C
> is not "getting in the way" - it is just letting you have a more
> convenient description than saying "the function foo takes a 32-bit
> unsigned integer in r0 and a pointer to an array of 8-bit data in r1".
20 years ago I was using a jpeg library in a .dll, which may or may not
have been written in C, but the header file it came with was. One of the
structs used was a 20KB monster, of which I only needed a handful of
fields.
After I finished with it, my version looked like this (notice the size
of the first field)
type jpeg_properties=record
[19966]byte padding !skip complicated jpeg stuff
int16 jfif_app0_units !19966
int16 jfif_app0_xdensity !19968
int16 jfif_app0_ydensity !19970
ichar jpeg_comment !19972
int jpeg_comment_size !19976
int padding2 !19980, total size 19984
end
But only after messing around with a C program to determine and
double-check all those offsets and sizes.
This was also for x86, 32-bits, where a variety of call conventions were
in use.
A universal struct description shouldn't need to depend on using an
algorithm to determine offsets and padding. Or the size of a field.
--
bartc
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Re: C2 Aims to Modernize the C Language David Kleinecke <dkleinecke@gmail.com> - 2018-02-10 12:41 -0800
Re: C2 Aims to Modernize the C Language Chad <cdalten@gmail.com> - 2018-02-10 13:38 -0800
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-11 00:32 +0100
Re: C2 Aims to Modernize the C Language Thiago Adams <thiago.adams@gmail.com> - 2018-02-10 17:23 -0800
Re: C2 Aims to Modernize the C Language Anton Shepelev <anton.txt@gmail.com> - 2018-02-11 13:53 +0300
Re: C2 Aims to Modernize the C Language Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-11 13:26 +0000
Re: C2 Aims to Modernize the C Language Thiago Adams <thiago.adams@gmail.com> - 2018-02-11 13:04 -0800
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-11 01:34 +0000
Re: C2 Aims to Modernize the C Language Thiago Adams <thiago.adams@gmail.com> - 2018-02-10 17:42 -0800
Re: C2 Aims to Modernize the C Language "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2018-02-10 17:50 -0800
Re: C2 Aims to Modernize the C Language fir <profesor.fir@gmail.com> - 2018-02-14 11:54 -0800
Re: C2 Aims to Modernize the C Language "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2018-02-14 12:14 -0800
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-11 04:48 +0100
Re: C2 Aims to Modernize the C Language Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-10 22:35 -0700
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-11 13:25 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-11 11:18 +0000
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-11 21:57 +0000
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-12 14:10 +1300
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 11:11 +0000
Re: C2 Aims to Modernize the C Language Reinhardt Behm <rbehm@hushmail.com> - 2018-02-12 20:33 +0800
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 13:43 +0000
Re: C2 Aims to Modernize the C Language Thiago Adams <thiago.adams@gmail.com> - 2018-02-12 06:05 -0800
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-13 07:13 +1300
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 01:17 +0000
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-13 09:55 +0100
Re: C2 Aims to Modernize the C Language BGB <cr88192@hotmail.com> - 2018-02-13 12:28 -0600
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-14 11:36 +1300
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-14 00:59 +0000
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-14 15:19 +1300
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-14 14:07 +0000
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-03-06 15:46 +0000
Re: C2 Aims to Modernize the C Language BGB <cr88192@hotmail.com> - 2018-02-13 20:31 -0600
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-14 15:42 +1300
Re: C2 Aims to Modernize the C Language BGB <cr88192@hotmail.com> - 2018-02-14 01:13 -0600
Re: C2 Aims to Modernize the C Language Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-21 15:13 +0000
Re: C2 Aims to Modernize the C Language supercat@casperkitty.com - 2018-02-21 08:43 -0800
Re: C2 Aims to Modernize the C Language Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-21 19:21 +0000
Re: C2 Aims to Modernize the C Language Robert Wessel <robertwessel2@yahoo.com> - 2018-02-21 12:25 -0600
Re: C2 Aims to Modernize the C Language Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-21 19:28 +0000
Re: C2 Aims to Modernize the C Language Robert Wessel <robertwessel2@yahoo.com> - 2018-02-21 18:29 -0600
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-22 08:33 +1300
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-14 14:48 +0000
Re: C2 Aims to Modernize the C Language BGB <cr88192@hotmail.com> - 2018-02-14 11:54 -0600
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 20:41 +0000
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-12 00:00 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 00:59 +0000
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-12 12:29 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 12:18 +0000
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-12 15:27 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 15:19 +0000
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-12 16:49 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 17:16 +0000
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-13 07:30 +1300
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-12 22:37 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 22:15 +0000
Re: C2 Aims to Modernize the C Language Ian Collins <ian-news@hotmail.com> - 2018-02-13 17:05 +1300
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 11:11 +0000
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-13 10:32 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 11:10 +0000
Re: C2 Aims to Modernize the C Language gordonb.5itdn@burditt.org (Gordon Burditt) - 2018-02-14 12:57 -0600
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-14 20:29 +0000
Re: C2 Aims to Modernize the C Language gordonb.nrdl0@burditt.org (Gordon Burditt) - 2018-02-14 19:22 -0600
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-15 14:59 +0000
Re: C2 Aims to Modernize the C Language already5chosen@yahoo.com - 2018-02-13 04:00 -0800
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-13 14:46 +0100
Re: C2 Aims to Modernize the C Language already5chosen@yahoo.com - 2018-02-13 08:49 -0800
Re: C2 Aims to Modernize the C Language Thiago Adams <thiago.adams@gmail.com> - 2018-02-13 09:52 -0800
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-13 13:47 +0100
Re: C2 Aims to Modernize the C Language already5chosen@yahoo.com - 2018-02-13 05:11 -0800
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-13 14:49 +0100
Re: C2 Aims to Modernize the C Language "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-13 21:52 +0800
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 14:45 +0000
Re: C2 Aims to Modernize the C Language Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-13 07:45 -0800
Re: C2 Aims to Modernize the C Language Chad <cdalten@gmail.com> - 2018-02-13 05:35 -0800
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 13:21 +0000
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 13:24 +0000
Re: C2 Aims to Modernize the C Language Egor <egor@ruby.local> - 2018-02-13 13:14 +0200
Re: C2 Aims to Modernize the C Language already5chosen@yahoo.com - 2018-02-13 04:38 -0800
Re: C2 Aims to Modernize the C Language Egor <egor@ruby.local> - 2018-02-14 13:25 +0200
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-13 13:39 +0000
Re: C2 Aims to Modernize the C Language Egor <egor@ruby.local> - 2018-02-14 13:42 +0200
Re: C2 Aims to Modernize the C Language supercat@casperkitty.com - 2018-02-15 13:17 -0800
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-11 04:41 +0100
Re: C2 Aims to Modernize the C Language Manfred <noname@invalid.add> - 2018-02-12 17:25 +0100
Re: C2 Aims to Modernize the C Language Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-12 17:28 +0000
Re: C2 Aims to Modernize the C Language Manfred <noname@invalid.add> - 2018-02-12 21:01 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 17:51 +0000
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-12 19:28 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 20:02 +0000
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-12 23:32 +0100
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-13 10:42 +0100
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-13 13:26 +0100
Re: C2 Aims to Modernize the C Language Richard Damon <Richard@Damon-Family.org> - 2018-02-13 08:06 -0500
Re: C2 Aims to Modernize the C Language Manfred <noname@invalid.add> - 2018-02-13 15:16 +0100
Re: C2 Aims to Modernize the C Language David Brown <david.brown@hesbynett.no> - 2018-02-13 14:53 +0100
Re: C2 Aims to Modernize the C Language BGB <cr88192@hotmail.com> - 2018-02-13 15:22 -0600
Re: C2 Aims to Modernize the C Language Keith Thompson <kst-u@mib.org> - 2018-02-12 12:26 -0800
Re: C2 Aims to Modernize the C Language GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-12 23:45 +0100
Re: C2 Aims to Modernize the C Language "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2018-02-12 15:52 -0800
Re: C2 Aims to Modernize the C Language Chad <cdalten@gmail.com> - 2018-02-12 17:13 -0800
Re: C2 Aims to Modernize the C Language Manfred <noname@invalid.add> - 2018-02-12 21:15 +0100
Re: C2 Aims to Modernize the C Language bartc <bc@freeuk.com> - 2018-02-12 21:42 +0000
Re: C2 Aims to Modernize the C Language Manfred <noname@invalid.add> - 2018-02-12 23:21 +0100
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