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Groups > comp.lang.c++ > #67345 > unrolled thread
| Started by | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| First post | 2019-08-07 07:13 +0200 |
| Last post | 2019-08-08 17:14 +0200 |
| Articles | 20 on this page of 215 — 20 participants |
Back to article view | Back to comp.lang.c++
Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 07:13 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-06 23:20 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 08:57 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 00:22 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 09:26 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 00:33 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 09:52 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 13:37 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 08:06 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 08:14 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson " <ahh_f_it@crap.nothing> - 2019-08-08 00:00 -0700
Re: Performance of unaligned memory-accesses "Chris M. Thomasson " <ahh_f_it@crap.nothing> - 2019-08-07 23:59 -0700
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-08-17 22:13 -0700
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 00:35 -0700
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 14:47 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 16:55 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 15:11 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 17:41 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 15:58 +0000
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 00:24 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 10:07 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 20:55 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 08:03 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 23:54 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 08:57 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 22:42 -0700
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 14:46 +0000
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 14:09 -0700
Re: Performance of unaligned memory-accesses Paavo Helde <myfirstname@osa.pri.ee> - 2019-08-07 11:00 +0300
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 10:03 +0200
Re: Performance of unaligned memory-accesses Paavo Helde <myfirstname@osa.pri.ee> - 2019-08-07 11:46 +0300
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 11:19 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 13:13 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 13:29 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 14:02 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 14:08 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 15:57 +0200
Re: Performance of unaligned memory-accesses Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-08-07 12:37 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 14:47 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 16:18 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 16:53 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 17:30 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 17:39 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 18:12 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 18:33 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 21:32 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 22:01 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 22:48 +0200
Re: Performance of unaligned memory-accesses Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2019-08-07 23:02 +0100
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 07:43 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 22:54 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 08:04 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-08 00:16 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 09:58 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-08 01:20 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 16:47 +0200
Re: Performance of unaligned memory-accesses Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2019-08-08 10:29 +0100
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 16:50 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 17:05 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 17:33 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 09:56 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 16:51 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 17:10 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 17:35 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 17:38 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 21:45 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-08 20:00 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 06:52 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 07:59 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-09 09:19 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 09:32 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-09 10:14 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 10:21 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-09 13:01 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 13:09 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-09 15:38 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 15:45 +0200
Re: Performance of unaligned memory-accesses Robert Wessel <robertwessel2@yahoo.com> - 2019-08-09 09:37 -0500
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 16:59 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 17:04 +0200
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-09 16:43 +0100
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 19:18 +0200
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-09 23:28 +0100
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-10 08:55 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-10 17:21 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-10 17:25 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-10 23:32 +0200
Re: Performance of unaligned memory-accesses Ian Collins <ian-news@hotmail.com> - 2019-08-11 10:59 +1200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 02:24 +0200
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-10 17:53 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 17:26 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 19:18 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 23:00 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 23:44 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 23:46 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-12 01:02 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 09:15 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@example.com> - 2019-08-11 16:37 -0700
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@example.com> - 2019-08-11 16:42 -0700
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@example.com> - 2019-08-11 22:05 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 07:25 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 07:24 +0200
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-10 17:22 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 07:23 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-10 17:10 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-10 17:21 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-10 17:31 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-10 23:47 +0200
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-10 17:40 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 07:27 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-10 23:46 +0200
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-10 23:22 +0100
Re: Performance of unaligned memory-accesses James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-10 16:11 -0700
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-10 17:32 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 15:41 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 15:55 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 18:06 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 18:15 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 18:59 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 19:03 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 23:48 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 00:15 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-12 01:06 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 09:13 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-12 13:32 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 13:40 +0200
Re: Performance of unaligned memory-accesses Melzzzzz <Melzzzzz@zzzzz.com> - 2019-08-12 11:44 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 14:30 +0200
Re: Performance of unaligned memory-accesses Melzzzzz <Melzzzzz@zzzzz.com> - 2019-08-12 13:09 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 15:14 +0200
Re: Performance of unaligned memory-accesses Melzzzzz <Melzzzzz@zzzzz.com> - 2019-08-12 19:13 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 21:15 +0200
Re: Performance of unaligned memory-accesses Melzzzzz <Melzzzzz@zzzzz.com> - 2019-08-12 19:25 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-13 02:28 +0200
Re: Performance of unaligned memory-accesses Melzzzzz <Melzzzzz@zzzzz.com> - 2019-08-13 01:08 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-13 16:03 +0200
Re: Performance of unaligned memory-accesses Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-14 09:27 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-14 20:51 +0200
Re: Performance of unaligned memory-accesses Öö Tiib <ootiib@hot.ee> - 2019-08-14 13:14 -0700
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-14 15:04 -0700
Re: Performance of unaligned memory-accesses Öö Tiib <ootiib@hot.ee> - 2019-08-14 15:47 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-15 10:15 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-15 07:11 +0200
Re: Performance of unaligned memory-accesses Öö Tiib <ootiib@hot.ee> - 2019-08-14 23:37 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-15 09:25 +0200
Re: Performance of unaligned memory-accesses Öö Tiib <ootiib@hot.ee> - 2019-08-15 03:41 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-15 14:25 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-15 16:06 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-15 16:21 +0200
Re: Performance of unaligned memory-accesses Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-15 16:56 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-16 06:44 +0200
Re: Performance of unaligned memory-accesses James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-14 16:53 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 18:40 +0200
Re: Performance of unaligned memory-accesses Ralf Goertz <me@myprovider.invalid> - 2019-08-13 08:53 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-13 09:18 +0200
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-11 19:00 +0100
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 21:06 +0200
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-11 13:07 -0700
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-11 23:58 +0100
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-11 17:07 -0700
Re: Performance of unaligned memory-accesses Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2019-08-12 10:14 +0100
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 11:30 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 13:03 +0200
Re: Performance of unaligned memory-accesses Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2019-08-12 13:06 +0100
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-12 10:34 +0100
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-12 08:49 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 18:10 +0200
Re: Performance of unaligned memory-accesses Öö Tiib <ootiib@hot.ee> - 2019-08-12 09:22 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-12 18:24 +0200
Re: Performance of unaligned memory-accesses James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-12 16:38 -0700
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-12 09:33 -0700
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-11 13:11 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 23:59 +0200
Re: Performance of unaligned memory-accesses James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-10 19:31 -0400
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-11 15:52 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-11 07:28 +0200
Re: Performance of unaligned memory-accesses James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-10 16:37 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-09 21:35 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 21:43 +0200
Re: Performance of unaligned memory-accesses Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-08-08 12:51 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 16:55 +0200
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 16:57 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 16:07 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 18:38 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 17:34 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 20:07 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 20:16 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 22:42 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-07 21:19 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 23:40 +0200
Re: Performance of unaligned memory-accesses Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-08-07 19:58 +0000
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-07 22:08 +0200
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 22:13 +0200
Re: Performance of unaligned memory-accesses Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-08-21 20:26 +0000
Re: Performance of unaligned memory-accesses Christopher Collins <ccollins476ad@gmail.com> - 2019-08-07 12:50 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-07 22:18 +0200
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-07 22:52 +0100
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-07 17:52 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 10:39 +0200
Re: Performance of unaligned memory-accesses Bart <bc@freeuk.com> - 2019-08-08 13:48 +0100
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 15:53 +0200
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-07 17:27 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 10:43 +0200
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-08 13:33 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 23:34 +0200
Re: Performance of unaligned memory-accesses Christopher Collins <ccollins476ad@gmail.com> - 2019-08-07 17:28 -0700
Re: Performance of unaligned memory-accesses Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-08 09:30 +0200
Re: Performance of unaligned memory-accesses "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-08-07 14:20 -0700
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-07 17:27 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 11:39 +0200
Re: Performance of unaligned memory-accesses Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-08-07 19:48 +0000
Re: Performance of unaligned memory-accesses Keith Thompson <kst-u@mib.org> - 2019-08-07 15:51 -0700
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 12:51 +0200
Re: Performance of unaligned memory-accesses scott@slp53.sl.home (Scott Lurndal) - 2019-08-08 14:46 +0000
Re: Performance of unaligned memory-accesses David Brown <david.brown@hesbynett.no> - 2019-08-08 17:14 +0200
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| From | David Brown <david.brown@hesbynett.no> |
|---|---|
| Date | 2019-08-11 23:48 +0200 |
| Message-ID | <qiq2fa$lo9$1@dont-email.me> |
| In reply to | #67565 |
On 11/08/2019 19:03, Bonita Montero wrote: >>> If the compilers wouldn't allow this, they wouldn't allow taking the >>> adddress of an unaligned member, but just accessig it with obj.member. > >> Ah, the old "it compiles so it must work" argument? > > The compiler can't warn you about everything you're doing wrong. Correct. What you are doing with unaligned pointers is likely to be wrong, but the compiler is not warning you. > But this would be clearly recognizable by the compiler and if this > would be an issue you would at least get a warning. You might think so - and I would like that to be the case. But very often, compilers do not warn about things that are clearly wrong, especially with default options. gcc can warn about various unaligned pointer cases, but only if you enable the warnings. This is not a perfect situation IMHO - I'd rather have these warnings enabled by default. Unfortunately, because some people think the rules of the language don't apply to them, there is quite a bit of code that works in practice while falling foul of this sort of thing, and that would lead to many warnings and annoyed users. After all, undefined behaviour means no guarantees of success, not a guarantee of failure. And many programmers are happy enough with "it worked when I tried it" rather than writing careful and correct code.
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-12 00:15 +0200 |
| Message-ID | <qiq42s$h1r$1@news.albasani.net> |
| In reply to | #67576 |
>> The compiler can't warn you about everything you're doing wrong. > Correct. What you are doing with unaligned pointers is likely to > be wrong, but the compiler is not warning you. It is ridiculous to expect a compiler for an CPU-architecture which supports unaligned operations not to support this. There are useful applications for this and there's nothing to do to implement this (supporting pointers to operate on unaligned data; supporting #pragma pack of course needs special implementation). So the people expect this to work. And there's no technical reason why this might not work as expected on these architectures.
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| From | David Brown <david.brown@hesbynett.no> |
|---|---|
| Date | 2019-08-12 01:06 +0200 |
| Message-ID | <qiq710$df5$1@dont-email.me> |
| In reply to | #67578 |
On 12/08/2019 00:15, Bonita Montero wrote: >>> The compiler can't warn you about everything you're doing wrong. > >> Correct. What you are doing with unaligned pointers is likely to >> be wrong, but the compiler is not warning you. > > It is ridiculous to expect a compiler for an CPU-architecture which > supports unaligned operations not to support this. Sorry, I thought we were talking about programming in C++, not in assembly. > There are useful > applications for this There are a few occasions when it could be useful, but none where it could not be handled just as well using methods that are defined behaviour. (Either defined by the standards, or defined - documented - by the compiler.) > and there's nothing to do to implement this > (supporting pointers to operate on unaligned data; supporting #pragma > pack of course needs special implementation). So the people expect > this to work. And there's no technical reason why this might not > work as expected on these architectures. Certainly some people expect it to work. The question is whether compiler writers expect it to work. I can't tell what compiler writers are thinking, but I can certainly tell what they write in their documentation, and I have not seen them saying that unaligned accesses are supported except by very specific use of packed structs.
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-12 09:13 +0200 |
| Message-ID | <qir3ig$92o$1@news.albasani.net> |
| In reply to | #67581 |
>> It is ridiculous to expect a compiler for an CPU-architecture which >> supports unaligned operations not to support this. > Sorry, I thought we were talking about programming in C++, not in assembly. We're talking about specific compiler-implementations. > Certainly some people expect it to work. > The question is whether compiler writers expect it to work. A compiler can't distinguish between unaligned and aligned pointers. In both cases it generates the same code. If the code really runs depends on the CPU and / or the OS.
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| From | David Brown <david.brown@hesbynett.no> |
|---|---|
| Date | 2019-08-12 13:32 +0200 |
| Message-ID | <qirio5$fr0$1@dont-email.me> |
| In reply to | #67586 |
On 12/08/2019 09:13, Bonita Montero wrote:
>>> It is ridiculous to expect a compiler for an CPU-architecture which
>>> supports unaligned operations not to support this.
>
>> Sorry, I thought we were talking about programming in C++, not in
>> assembly.
>
> We're talking about specific compiler-implementations.
Specific compiler implementations do not necessarily support or use all
the features of the target CPU. If you want that, use assembly. C and
C++ are defined mainly in terms of an abstract machine, not how things
work at the cpu level.
>
>> Certainly some people expect it to work.
>> The question is whether compiler writers expect it to work.
>
> A compiler can't distinguish between unaligned and aligned pointers.
That is why using unaligned pointers is undefined behaviour, not a
constraint requiring the compiler to give a compile-time diagnostic.
But the compiler /can/ assume that any pointer you are using is aligned
- unless it has specific extra features to support unaligned pointers.
When a compiler does not /document/ such features, it does not guarantee
them in any way - you do not /know/ that it supports unaligned pointers.
And you have repeatedly failed to show any reference for such support
in any compiler - you have merely repeatedly shown that you don't
understand the issue and you incorrectly extrapolate from packed struct
support.
You are correct that a compiler can't distinguish between unaligned and
aligned pointers, if the source of the pointer is not visible at the
time. But that does not stop it from being able to assume that it is
properly aligned if you have dereferenced it.
Given this function (with 4-byte ints) :
int read_int(const void * p) {
const int * q = (const int *) p;
uintptr_t x = (uintptr_t) q;
if (x & 0x03) {
int y;
memcpy(&y, q, sizeof y);
return y;
} else {
return * (const int *) q;
}
}
The compiler knows that q is correctly aligned - otherwise its
initialisation would be undefined behaviour, and can assume that hasn't
happened (or that the programmer doesn't care if it does happen). Thus
the whole thing can be reduced to a single word load instruction, even
on processors that don't support unaligned access.
Would a compiler do this sort of optimisation? I expect not (on targets
that don't support unaligned access), at least not without explicit
optimisation flags - because too many programmers, like you, don't
understand the language details. But there is nothing in the standards,
and nothing in any compiler documentation I have seen, that prevents it.
> In both cases it generates the same code. If the code really runs
> depends on the CPU and / or the OS.
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-12 13:40 +0200 |
| Message-ID | <qirj6o$6gp$1@news.albasani.net> |
| In reply to | #67592 |
>> We're talking about specific compiler-implementations.
> Specific compiler implementations do not necessarily support or use all
> the features of the target CPU. If you want that, use assembly. C and
> C++ are defined mainly in terms of an abstract machine, not how things
> work at the cpu level.
We're talking about specific compiler-implementations. And
implementations for CPUs with unaligned access allow this.
And in this case this is not even relly a feature of the
compiler since unaligned and aligned pointers are indistin-
guishable by the compiler. So even on CPUs without support
for unaligned accesses the compiler generates the desired
code; it if really runs depends on the OS´.
>> A compiler can't distinguish between unaligned and aligned pointers.
> That is why using unaligned pointers is undefined behaviour, ...
We're talking about specific compiler-implementations.
> You are correct that a compiler can't distinguish between unaligned and
> aligned pointers, if the source of the pointer is not visible at the
> time. But that does not stop it from being able to assume that it is
> properly aligned if you have dereferenced it.
> Given this function (with 4-byte ints) :
> int read_int(const void * p) {
> const int * q = (const int *) p;
> uintptr_t x = (uintptr_t) q;
> if (x & 0x03) {
> int y;
> memcpy(&y, q, sizeof y);
> return y;
> } else {
> return * (const int *) q;
> }
> }
> The compiler knows that q is correctly aligned - otherwise its
> initialisation would be undefined behaviour, ...
Pure therory! In practice the code would even run if int y is unaligned
on a machine with support for unaligned accesses or on a machine that
emulates the access (f.e. if you have y in a packedstruct). But in every
case this depends not on the compiler.
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| From | Melzzzzz <Melzzzzz@zzzzz.com> |
|---|---|
| Date | 2019-08-12 11:44 +0000 |
| Message-ID | <_ic4F.727$t92.96@fx25.am4> |
| In reply to | #67592 |
On 2019-08-12, David Brown <david.brown@hesbynett.no> wrote: > On 12/08/2019 09:13, Bonita Montero wrote: >>>> It is ridiculous to expect a compiler for an CPU-architecture which >>>> supports unaligned operations not to support this. >> >>> Sorry, I thought we were talking about programming in C++, not in >>> assembly. >> >> We're talking about specific compiler-implementations. > > Specific compiler implementations do not necessarily support or use all > the features of the target CPU. If you want that, use assembly. C and > C++ are defined mainly in terms of an abstract machine, not how things > work at the cpu level. > >> >>> Certainly some people expect it to work. >>> The question is whether compiler writers expect it to work. >> >> A compiler can't distinguish between unaligned and aligned pointers. > > That is why using unaligned pointers is undefined behaviour, not a > constraint requiring the compiler to give a compile-time diagnostic. In practice you know what has to be aligned and what not. On x86 only some SSE instructions demand 16 bytes alignement, that was later removed with 32 byte version. All in all with SSE you had to explicitelly specify alignment with compiler extension on gcc, don't know for others as alsmost all follow gcc as standard. -- press any key to continue or any other to quit... U ničemu ja ne uživam kao u svom statusu INVALIDA -- Zli Zec Na divljem zapadu i nije bilo tako puno nasilja, upravo zato jer su svi bili naoruzani. -- Mladen Gogala
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-12 14:30 +0200 |
| Message-ID | <qirm5l$nog$1@news.albasani.net> |
| In reply to | #67594 |
The thing is simply, that unaligned access is undefined behaviour not because the compilers aren't able to generate proper code (they are, i.e. they don't say f.e. "if( (uint_ptr)pI & 0x3 ) fuckyou();" ;-) ), but because the CPU and / or OS might not support this at runtime.
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| From | Melzzzzz <Melzzzzz@zzzzz.com> |
|---|---|
| Date | 2019-08-12 13:09 +0000 |
| Message-ID | <7yd4F.2$CO2.0@fx30.am4> |
| In reply to | #67596 |
On 2019-08-12, Bonita Montero <Bonita.Montero@gmail.com> wrote: > The thing is simply, that unaligned access is undefined behaviour not > because the compilers aren't able to generate proper code (they are, > i.e. they don't say f.e. "if( (uint_ptr)pI & 0x3 ) fuckyou();" ;-) ), > but because the CPU and / or OS might not support this at runtime. Accessing char is not undefined behavior. -- press any key to continue or any other to quit... U ničemu ja ne uživam kao u svom statusu INVALIDA -- Zli Zec Na divljem zapadu i nije bilo tako puno nasilja, upravo zato jer su svi bili naoruzani. -- Mladen Gogala
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-12 15:14 +0200 |
| Message-ID | <qirood$juq$1@news.albasani.net> |
| In reply to | #67597 |
>> The thing is simply, that unaligned access is undefined behaviour not >> because the compilers aren't able to generate proper code (they are, >> i.e. they don't say f.e. "if( (uint_ptr)pI & 0x3 ) fuckyou();" ;-) ), >> but because the CPU and / or OS might not support this at runtime. > Accessing char is not undefined behavior. You might be stupid, but that not stupid.
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| From | Melzzzzz <Melzzzzz@zzzzz.com> |
|---|---|
| Date | 2019-08-12 19:13 +0000 |
| Message-ID | <yTi4F.20875$xm3.4967@fx15.am4> |
| In reply to | #67598 |
On 2019-08-12, Bonita Montero <Bonita.Montero@gmail.com> wrote: >>> The thing is simply, that unaligned access is undefined behaviour not >>> because the compilers aren't able to generate proper code (they are, >>> i.e. they don't say f.e. "if( (uint_ptr)pI & 0x3 ) fuckyou();" ;-) ), >>> but because the CPU and / or OS might not support this at runtime. > >> Accessing char is not undefined behavior. > > You might be stupid, but that not stupid. > Sure, give example of unaligned access to char. -- press any key to continue or any other to quit... U ničemu ja ne uživam kao u svom statusu INVALIDA -- Zli Zec Na divljem zapadu i nije bilo tako puno nasilja, upravo zato jer su svi bili naoruzani. -- Mladen Gogala
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-12 21:15 +0200 |
| Message-ID | <qisdt1$6rn$2@news.albasani.net> |
| In reply to | #67605 |
>>>> The thing is simply, that unaligned access is undefined behaviour not >>>> because the compilers aren't able to generate proper code (they are, >>>> i.e. they don't say f.e. "if( (uint_ptr)pI & 0x3 ) fuckyou();" ;-) ), >>>> but because the CPU and / or OS might not support this at runtime. >>> Accessing char is not undefined behavior. >> You might be stupid, but that not stupid. > Sure, give example of unaligned access to char. No, everyone can guess from the "0x3" that pI points to a 32 bit integer - exept you.
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| From | Melzzzzz <Melzzzzz@zzzzz.com> |
|---|---|
| Date | 2019-08-12 19:25 +0000 |
| Message-ID | <R2j4F.13718$GfB1.12724@fx36.am4> |
| In reply to | #67606 |
On 2019-08-12, Bonita Montero <Bonita.Montero@gmail.com> wrote: >>>>> The thing is simply, that unaligned access is undefined behaviour not >>>>> because the compilers aren't able to generate proper code (they are, >>>>> i.e. they don't say f.e. "if( (uint_ptr)pI & 0x3 ) fuckyou();" ;-) ), >>>>> but because the CPU and / or OS might not support this at runtime. > >>>> Accessing char is not undefined behavior. > >>> You might be stupid, but that not stupid. > >> Sure, give example of unaligned access to char. > > No, everyone can guess from the "0x3" that pI points to a 32 bit > integer - exept you. No it can't. pI can point to anything. But I even don't look into that. I comment assertion that unaligned access is undefined behavior, which is not always true. eg you can cast to char* and access anything. You can use memcpy to copy contents as well. -- press any key to continue or any other to quit... U ničemu ja ne uživam kao u svom statusu INVALIDA -- Zli Zec Na divljem zapadu i nije bilo tako puno nasilja, upravo zato jer su svi bili naoruzani. -- Mladen Gogala
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-13 02:28 +0200 |
| Message-ID | <qit07a$qpk$1@news.albasani.net> |
| In reply to | #67607 |
>> No, everyone can guess from the "0x3" that pI points to a 32 bit >> integer - exept you. > No it can't. pI can point to anything. 0x3 wouldn't make sense for a unaligned-check pointer to a char.
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| From | Melzzzzz <Melzzzzz@zzzzz.com> |
|---|---|
| Date | 2019-08-13 01:08 +0000 |
| Message-ID | <s4o4F.580$_l5.212@fx32.am4> |
| In reply to | #67610 |
On 2019-08-13, Bonita Montero <Bonita.Montero@gmail.com> wrote: >>> No, everyone can guess from the "0x3" that pI points to a 32 bit >>> integer - exept you. > >> No it can't. pI can point to anything. > > 0x3 wouldn't make sense for a unaligned-check pointer to a char. Again, I commented assertion that unaligned access causes undefined behavior. And I don't care what 0x3 means. -- press any key to continue or any other to quit... U ničemu ja ne uživam kao u svom statusu INVALIDA -- Zli Zec Na divljem zapadu i nije bilo tako puno nasilja, upravo zato jer su svi bili naoruzani. -- Mladen Gogala
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-13 16:03 +0200 |
| Message-ID | <qiufut$cde$1@news.albasani.net> |
| In reply to | #67611 |
> Again, I commented assertion that unaligned access causes undefined > behavior. And I don't care what 0x3 means. As I said that's not undefined behaviour because the compiler would be unable to generate the code as expected but because the CPU might fail / trap an unaligned access at runtime and the OS might emulate tzhe unaligned access or not. So it depends on the platform you target.
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| From | Tim Rentsch <tr.17687@z991.linuxsc.com> |
|---|---|
| Date | 2019-08-14 09:27 -0700 |
| Message-ID | <86mugb7lvg.fsf@mailhub.linuxsc.com> |
| In reply to | #67619 |
Bonita Montero <Bonita.Montero@gmail.com> writes: >> Again, I commented assertion that unaligned access causes undefined >> behavior. And I don't care what 0x3 means. > > As I said that's not undefined behaviour because the compiler would > be unable to generate the code as expected but because the CPU might > fail / trap an unaligned access at runtime and the OS might emulate > tzhe unaligned access or not. So it depends on the platform you > target. If a given operation has undefined behavior, it doesn't stop having undefined behavior just because it happens to do what you want it to.
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| From | Bonita Montero <Bonita.Montero@gmail.com> |
|---|---|
| Date | 2019-08-14 20:51 +0200 |
| Message-ID | <qj1l7a$b1i$1@news.albasani.net> |
| In reply to | #67654 |
>> As I said that's not undefined behaviour because the compiler would >> be unable to generate the code as expected but because the CPU might >> fail / trap an unaligned access at runtime and the OS might emulate >> tzhe unaligned access or not. So it depends on the platform you >> target. > If a given operation has undefined behavior, it doesn't stop > having undefined behavior just because it happens to do what > you want it to. In theory, but in practice it has an expectable behaviour depending on the platform.
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| From | Öö Tiib <ootiib@hot.ee> |
|---|---|
| Date | 2019-08-14 13:14 -0700 |
| Message-ID | <d6d186f1-45fa-4a1c-9d5f-1154f9b9ac5d@googlegroups.com> |
| In reply to | #67656 |
On Wednesday, 14 August 2019 21:51:32 UTC+3, Bonita Montero wrote: > >> As I said that's not undefined behaviour because the compiler would > >> be unable to generate the code as expected but because the CPU might > >> fail / trap an unaligned access at runtime and the OS might emulate > >> tzhe unaligned access or not. So it depends on the platform you > >> target. > > > If a given operation has undefined behavior, it doesn't stop > > having undefined behavior just because it happens to do what > > you want it to. > > In theory, but in practice it has an expectable behaviour depending > on the platform. So it may change because of change of compiler, its version, compiling options, device that it is ran on, settings of operating system or other (possibly unrelated) code in same code-base. Program that happens to do something in narrow conditions but not in others is unreliable and unreliability is the most disliked property of software.
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| From | Keith Thompson <kst-u@mib.org> |
|---|---|
| Date | 2019-08-14 15:04 -0700 |
| Message-ID | <lnlfvv5rp9.fsf@kst-u.example.com> |
| In reply to | #67657 |
Öö Tiib <ootiib@hot.ee> writes:
> On Wednesday, 14 August 2019 21:51:32 UTC+3, Bonita Montero wrote:
>> >> As I said that's not undefined behaviour because the compiler would
>> >> be unable to generate the code as expected but because the CPU might
>> >> fail / trap an unaligned access at runtime and the OS might emulate
>> >> tzhe unaligned access or not. So it depends on the platform you
>> >> target.
>>
>> > If a given operation has undefined behavior, it doesn't stop
>> > having undefined behavior just because it happens to do what
>> > you want it to.
>>
>> In theory, but in practice it has an expectable behaviour depending
>> on the platform.
>
> So it may change because of change of compiler, its version, compiling
> options, device that it is ran on, settings of operating system or
> other (possibly unrelated) code in same code-base.
> Program that happens to do something in narrow conditions but not in
> others is unreliable and unreliability is the most disliked property
> of software.
It's important to remember what "undefined behavior" means. It's not
"this program will blow up". It is simply
behavior for which this document imposes no requirements
where "this document" is the C++ standard. If something other than
the standard imposes requirements, it's still undefined behavior.
If you want to talk about unexpected or undesirable behavior,
call it that. That's not what "undefined behavior" means.
--
Keith Thompson (The_Other_Keith) kst-u@mib.org <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */
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