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Groups > comp.lang.c > #104032
| From | Keith Thompson <kst-u@mib.org> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: What if pre-processor was moved to parser? |
| Date | 2017-02-16 12:24 -0800 |
| Organization | None to speak of |
| Message-ID | <lnshndrij7.fsf@kst-u.example.com> (permalink) |
| References | (9 earlier) <7cc856f7-997e-496d-8ebf-ba413cb89d75@googlegroups.com> <o84d1v$il5$1@dont-email.me> <7dc5b761-29bb-4244-aa99-ed20cbfa5fcd@googlegroups.com> <lnwpcqq8v7.fsf@kst-u.example.com> <ab4395b0-213c-4c70-beab-7a19ea1f020e@googlegroups.com> |
supercat@casperkitty.com writes:
> On Thursday, February 16, 2017 at 12:37:43 PM UTC-6, Keith Thompson wrote:
>> supercat writes:
>> [...]
>> > The ability to compile a C program as C++ is only useful if the
>> > resulting program will run with known semantics. There are some
>> > constructs which have defined behavior in C but have no convenient
>> > direct equivalent in C++.
>>
>> For example?
>
> I'm not a C++ expert by any means, but by my understanding it requires
> that after one union member is used, any attempt to use another member
> without first using placement new yields UB. Adding placement new might
> not be a problem except that the Standard makes no guarantee about the
> contents of any portion of the newly-selected member--even parts which
> would share a Common Initial Sequence with the previously accessed member.
C++ has the common initial sequence rule; C++11 9.2p19 [class.mem] and
9.3p1 [class.union].
I don't see anything in the C++ standard that permits writing to one
member of a union and reading another, as C permits, but I could very
easily be missing something.
--
Keith Thompson (The_Other_Keith) kst-u@mib.org <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"
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What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-14 15:37 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-15 00:05 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-15 00:57 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-15 07:21 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-15 07:24 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-15 08:10 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 03:05 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-15 11:38 +0000
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 04:28 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-15 13:22 +0000
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 05:47 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 10:06 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 05:24 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-15 13:57 +0000
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-19 10:27 -0800
Re: What if pre-processor was moved to parser? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-15 15:16 +0000
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 08:14 -0800
Re: What if pre-processor was moved to parser? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-15 18:01 +0000
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-15 18:25 +0000
Re: What if pre-processor was moved to parser? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-15 19:14 +0000
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-15 10:25 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-15 18:45 +0000
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-15 20:03 +0100
Re: What if pre-processor was moved to parser? jameskuyper@verizon.net - 2017-02-15 10:12 -0800
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-15 10:51 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 12:14 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-15 20:25 +0000
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 12:50 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-16 11:50 +0000
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-16 04:44 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-16 05:28 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-16 14:32 +0000
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-16 09:13 -0800
Re: What if pre-processor was moved to parser? Keith Thompson <kst-u@mib.org> - 2017-02-16 10:38 -0800
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-16 11:55 -0800
Re: What if pre-processor was moved to parser? Keith Thompson <kst-u@mib.org> - 2017-02-16 12:24 -0800
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-16 21:32 +0100
Re: What if pre-processor was moved to parser? Keith Thompson <kst-u@mib.org> - 2017-02-16 12:55 -0800
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-16 22:41 +0100
Re: What if pre-processor was moved to parser? Keith Thompson <kst-u@mib.org> - 2017-02-16 14:02 -0800
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-16 15:08 -0800
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-16 13:32 -0800
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-17 21:19 +1300
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-17 12:01 +0100
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-17 09:16 -0800
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-17 18:55 +0100
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 08:07 +1300
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-17 20:12 +0100
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 11:04 +1300
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-17 22:38 +0000
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 11:47 +1300
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-17 14:55 -0800
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 12:11 +1300
Re: What if pre-processor was moved to parser? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-02-17 15:26 -0800
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-17 16:15 -0800
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 13:22 +1300
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-17 16:37 -0800
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-18 11:57 +0100
Re: What if pre-processor was moved to parser? Richard Heathfield <rjh@cpax.org.uk> - 2017-02-18 07:13 +0000
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 20:26 +1300
Re: What if pre-processor was moved to parser? Richard Heathfield <rjh@cpax.org.uk> - 2017-02-18 09:17 +0000
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-18 01:18 +0100
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 13:23 +1300
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-18 01:45 +0100
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 16:18 +1300
Re: What if pre-processor was moved to parser? Richard Heathfield <rjh@cpax.org.uk> - 2017-02-18 07:19 +0000
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-18 20:30 +1300
Re: What if pre-processor was moved to parser? Richard Heathfield <rjh@cpax.org.uk> - 2017-02-18 09:18 +0000
Re: What if pre-processor was moved to parser? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-02-18 07:15 -0800
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-24 09:24 -0800
Re: What if pre-processor was moved to parser? Richard Heathfield <rjh@cpax.org.uk> - 2017-02-24 17:51 +0000
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-24 10:08 -0700
Re: What if pre-processor was moved to parser? Richard Heathfield <rjh@cpax.org.uk> - 2017-04-24 18:58 +0100
Re: What if pre-processor was moved to parser? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2017-04-26 05:03 +0000
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-30 11:21 -0700
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-25 09:15 +1300
Re: What if pre-processor was moved to parser? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-02-24 17:29 -0800
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-26 06:19 -0700
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-04-26 16:04 +0200
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-04-26 07:08 -0700
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-04-26 16:46 +0200
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-04-26 09:32 -0700
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-04-26 20:19 +0200
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-04-26 11:29 -0700
Re: What if pre-processor was moved to parser? scott@slp53.sl.home (Scott Lurndal) - 2017-04-26 18:51 +0000
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-04-27 09:32 +1200
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-04-27 11:01 +0200
Re: What if pre-processor was moved to parser? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-04-27 02:23 -0700
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-04-27 21:31 +1200
Re: What if pre-processor was moved to parser? Ike Naar <ike@iceland.freeshell.org> - 2017-04-27 16:15 +0000
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-04-27 09:35 -0700
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-04-28 15:12 +0200
Re: What if pre-processor was moved to parser? Gareth Owen <gwowen@gmail.com> - 2017-04-27 19:13 +0100
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-04-27 11:37 +0200
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-04-27 15:18 +0200
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-18 08:43 +0100
Re: What if pre-processor was moved to parser? Richard Heathfield <rjh@cpax.org.uk> - 2017-02-18 09:22 +0000
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-18 09:44 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-18 11:33 +0000
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-18 13:25 +0100
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-18 13:47 +0000
Re: What if pre-processor was moved to parser? Jean-Marc Bourguet <jm@bourguet.org> - 2017-02-18 15:23 +0100
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-18 14:53 +0000
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-18 16:56 +0000
Re: What if pre-processor was moved to parser? Robert Wessel <robertwessel2@yahoo.com> - 2017-02-18 22:50 -0600
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-19 09:45 +0100
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-19 13:35 +0100
Re: What if pre-processor was moved to parser? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-02-18 11:24 -0500
Re: What if pre-processor was moved to parser? Robert Wessel <robertwessel2@yahoo.com> - 2017-02-18 22:48 -0600
Re: What if pre-processor was moved to parser? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-02-18 10:04 -0800
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-19 17:12 +0100
Re: What if pre-processor was moved to parser? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-02-19 11:11 -0800
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-19 21:14 +0100
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-19 21:22 +0100
Re: What if pre-processor was moved to parser? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-02-19 12:33 -0800
Re: What if pre-processor was moved to parser? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-02-19 12:31 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-19 13:14 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-19 14:50 -0800
Re: What if pre-processor was moved to parser? fir <profesor.fir@gmail.com> - 2017-02-19 15:04 -0800
Re: What if pre-processor was moved to parser? David Brown <david.brown@hesbynett.no> - 2017-02-20 10:13 +0100
Re: What if pre-processor was moved to parser? Gareth Owen <gwowen@gmail.com> - 2017-02-19 21:09 +0000
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-23 15:32 -0800
Re: What if pre-processor was moved to parser? Ian Collins <ian-news@hotmail.com> - 2017-02-24 12:44 +1300
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-19 21:04 -0800
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-19 21:14 -0800
Re: What if pre-processor was moved to parser? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2017-02-16 14:48 -0800
Re: What if pre-processor was moved to parser? Keith Thompson <kst-u@mib.org> - 2017-02-16 15:46 -0800
Re: What if pre-processor was moved to parser? Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-23 16:16 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-20 04:18 -0800
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-20 06:47 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-20 09:50 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-21 04:33 -0800
Re: What if pre-processor was moved to parser? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-02-21 15:41 +0100
Re: What if pre-processor was moved to parser? supercat@casperkitty.com - 2017-02-21 09:39 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-21 09:59 -0800
Re: What if pre-processor was moved to parser? TickleMe Elmo <tmelmosfire@gmail.com> - 2017-02-21 10:22 -0800
Re: What if pre-processor was moved to parser? BartC <bc@freeuk.com> - 2017-02-20 15:49 +0000
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-20 09:43 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 12:31 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-16 03:33 -0800
Re: What if pre-processor was moved to parser? jameskuyper@verizon.net - 2017-02-15 12:47 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 13:06 -0800
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-02-15 13:15 -0800
Re: What if pre-processor was moved to parser? "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-02-18 12:36 +0100
Re: What if pre-processor was moved to parser? "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-02-18 12:41 +0100
Re: What if pre-processor was moved to parser? John Bode <jfbode1029@gmail.com> - 2017-04-26 09:42 -0700
Re: What if pre-processor was moved to parser? Thiago Adams <thiago.adams@gmail.com> - 2017-04-26 09:58 -0700
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