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Groups > comp.lang.c++ > #67345 > unrolled thread

Performance of unaligned memory-accesses

Started byBonita Montero <Bonita.Montero@gmail.com>
First post2019-08-07 07:13 +0200
Last post2019-08-08 17:14 +0200
Articles 20 on this page of 215 — 20 participants

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Contents

  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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#67551

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-11 07:25 +0200
Message-ID<qio8st$279$3@news.albasani.net>
In reply to#67545
> You are missing a critical detail.  I said that no compiler would
> ever  rely on trapping and emulation for handling unaligned accesses
> to /packed/ objects.

Since you are allowed to get an address of such a packed objekt support
for standalone-pointers that do the same must be guaranteed also.

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#67550

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-11 07:24 +0200
Message-ID<qio8qc$279$2@news.albasani.net>
In reply to#67540
> Solaris SPARC?

Linux / SPARC also traps unaligned accesses.

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#67544

FromKeith Thompson <kst-u@mib.org>
Date2019-08-10 17:22 -0700
Message-ID<lnef1s8sb3.fsf@kst-u.example.com>
In reply to#67535
David Brown <david.brown@hesbynett.no> writes:
[...]
> The standard says that you can't do unaligned accesses.

No, it doesn't.  It says that unaligned accesses are undefined behavior.

>                                                          It is only if a 
> compiler documents that it allows such accesses that you can use it safely.

-- 
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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#67549

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-11 07:23 +0200
Message-ID<qio8p5$279$1@news.albasani.net>
In reply to#67535
> You've given no evidence to suggest that any OS emulates unaligned 
> access.  It might well be that some OS's do, for compatibility with 
> binaries for related processors - but your "proof by repeated assertion" 
> is getting tedious.

I didn't tell that every OS does this.

> No compiler would /ever/ rely on trapping and emulation for handling 
> unaligned accesses to packed objects - that would be absurdly inefficient.

The compiler doesn't care about trapping.
It just compiles unaligned accesse.

>>> No, C does not allow that - converting a value into a pointer type 
>>> that is not properly aligned is undefined behaviour.

>> This is done only on embedded-platforms with fixed adresses of hardware
>> -registers.

> You have no idea what you are talking about.

No, I'm knowing what I'm talking about.

>> So you're in the context of a certain compiler and hardware.
>> There you don't have to worry about what the standard says.

> The standard says that you can't do unaligned accesses.

We're talking about certain compilers and not about the standard.

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#67525

FromDavid Brown <david.brown@hesbynett.no>
Date2019-08-10 17:10 +0200
Message-ID<qimmpf$f3t$2@dont-email.me>
In reply to#67488
On 09/08/2019 17:43, Bart wrote:
> On 09/08/2019 16:04, Bonita Montero wrote:
>>> Check your compiler-documentation.
>>> It says that #pragma pack allows unaligned packing.
>>
>> MSVC-documentation:
>> "To pack a class is to place its members directly after each
>> other in memory, which can mean that some or all members can
>> be  ligned on a boundary smaller than the default alignment
>> the target architecture"
>> gcc supports the same kind of #pragma pack, even with the
>> same push- / pop-syntax. According to the documentation this
>> is to be MSVC-compatible here.
> 
> Being able to define such a layout doesn't necessarily mean that 
> unaligned accesses are supported by hardware.
> 

More importantly here, it also does not mean you can take pointers to 
the unaligned members and use them as normal pointers, nor does it mean 
that the compiler supports unaligned access in other cases - /even/ if 
the hardware supports it.

On platforms that don't support unaligned access in the hardware, 
accessing members of a "packed" struct will give you byte-by-byte 
instructions.  No guarantees are usually given if you take a pointer to 
the member and work from there.

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#67527

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-10 17:21 +0200
Message-ID<qimndh$8dh$1@news.albasani.net>
In reply to#67525
> More importantly here, it also does not mean you can take pointers
> to  the unaligned members and use them as normal pointers, ...

Quote the part of the standard that says that.

> ..., nor does it mean that the compiler supports unaligned access
> in other cases - /even/ if  the hardware supports it.

Which compiler does specify this? Show me a link to the documentation.

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#67529

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-10 17:31 +0200
Message-ID<qimo10$90k$1@news.albasani.net>
In reply to#67527
>> More importantly here, it also does not mean you can take pointers
>> to  the unaligned members and use them as normal pointers, ...

> Quote the part of the standard that says that.

Oh, I wasn't correct here: since #pragma pack is a compiler-specific
feature it sould be specified by the compiler-documentation that it
isn't legal to take the address of an unaligned member.
So show me some compilers documentations that say that it isn't
legal to take the address of an unaligned member!

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#67538

FromDavid Brown <david.brown@hesbynett.no>
Date2019-08-10 23:47 +0200
Message-ID<qine1u$om3$2@dont-email.me>
In reply to#67529
On 10/08/2019 17:31, Bonita Montero wrote:
>>> More importantly here, it also does not mean you can take pointers
>>> to  the unaligned members and use them as normal pointers, ...
> 
>> Quote the part of the standard that says that.
> 
> Oh, I wasn't correct here: since #pragma pack is a compiler-specific
> feature it sould be specified by the compiler-documentation that it
> isn't legal to take the address of an unaligned member.
> So show me some compilers documentations that say that it isn't
> legal to take the address of an unaligned member!

No, it would take compiler-specific documentation to say that it /is/ 
legal to take the address of an unaligned packed member - because the 
standard already says that this is undefined behaviour.  Thus if a 
compiler wants to say it is allowed, it must document it.

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#67547

FromKeith Thompson <kst-u@mib.org>
Date2019-08-10 17:40 -0700
Message-ID<ln5zn48rgq.fsf@kst-u.example.com>
In reply to#67538
David Brown <david.brown@hesbynett.no> writes:
> On 10/08/2019 17:31, Bonita Montero wrote:
>>>> More importantly here, it also does not mean you can take pointers
>>>> to the unaligned members and use them as normal pointers, ...
>> 
>>> Quote the part of the standard that says that.
>> 
>> Oh, I wasn't correct here: since #pragma pack is a compiler-specific
>> feature it sould be specified by the compiler-documentation that it
>> isn't legal to take the address of an unaligned member.
>> So show me some compilers documentations that say that it isn't
>> legal to take the address of an unaligned member!
>
> No, it would take compiler-specific documentation to say that it /is/ 
> legal to take the address of an unaligned packed member - because the 
> standard already says that this is undefined behaviour.  Thus if a 
> compiler wants to say it is allowed, it must document it.

If you're going to talk about things that are "legal" or "allowed",
please define what you mean by those words.  The standard doesn't
use them.

Is the program ill-formed?  Is its behavior undefined?  Does it
violate a diagnosable rule?

There are very few things that are not *allowed* by the language.

-- 
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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#67552

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-11 07:27 +0200
Message-ID<qio8vm$279$4@news.albasani.net>
In reply to#67538
> No, it would take compiler-specific documentation to say that it /is/ 
> legal to take the address of an unaligned packed member - because the 
> standard already says that this is undefined behaviour.  Thus if a 
> compiler wants to say it is allowed, it must document it.

The standard is irrelevant here since we are talking about secific
implementations with #pragma packed.

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#67537

FromDavid Brown <david.brown@hesbynett.no>
Date2019-08-10 23:46 +0200
Message-ID<qindvc$om3$1@dont-email.me>
In reply to#67527
On 10/08/2019 17:21, Bonita Montero wrote:
>> More importantly here, it also does not mean you can take pointers
>> to  the unaligned members and use them as normal pointers, ...
> 
> Quote the part of the standard that says that.

I already did.

These are from N1570, draft of C11 standard - C++ inherits this from C 
and the C standards are simpler.

6.3.2.3p7:
"""
A pointer to an object type may be converted to a pointer to a different 
object type. If the resulting pointer is not correctly aligned 68) for 
the referenced type, the behavior is undefined.
"""

6.5.3.2p4:
"""
If an invalid value has been assigned to the pointer, the behavior of 
the unary * operator is
undefined. 102)
"""

Footnote 102:

"""
Among the invalid values for dereferencing a pointer by the unary * 
operator are a null pointer, an address inappropriately aligned for the 
type of object pointed to, and the address of an object after the end of 
its lifetime.
"""


> 
>> ..., nor does it mean that the compiler supports unaligned access
>> in other cases - /even/ if  the hardware supports it.
> 
> Which compiler does specify this? Show me a link to the documentation.

Compilers don't document things they /don't/ do - the document things 
that they /do/.

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#67539

FromBart <bc@freeuk.com>
Date2019-08-10 23:22 +0100
Message-ID<ftH3F.817022$T66.487531@fx14.am4>
In reply to#67537
On 10/08/2019 22:46, David Brown wrote:
> On 10/08/2019 17:21, Bonita Montero wrote:
>>> More importantly here, it also does not mean you can take pointers
>>> to  the unaligned members and use them as normal pointers, ...
>>
>> Quote the part of the standard that says that.
> 
> I already did.
> 
> These are from N1570, draft of C11 standard - C++ inherits this from C 
> and the C standards are simpler.
> 
> 6.3.2.3p7:
> """
> A pointer to an object type may be converted to a pointer to a different 
> object type. If the resulting pointer is not correctly aligned 68) for 
> the referenced type, the behavior is undefined.
> """


What does 'correctly aligned' mean?

Does C not allow the address of a 32-bit int to be at anything other 
than a multiple of 4, when the machine has byte-addressed memory, even 
when the hardware allows it?

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#67541

FromJames Kuyper <jameskuyper@alumni.caltech.edu>
Date2019-08-10 16:11 -0700
Message-ID<52b7afac-e701-40d9-8257-d9cfa7c51243@googlegroups.com>
In reply to#67539
On Saturday, August 10, 2019 at 6:23:16 PM UTC-4, Bart wrote:
> On 10/08/2019 22:46, David Brown wrote:
...
> > 6.3.2.3p7:
> > """
> > A pointer to an object type may be converted to a pointer to a different 
> > object type. If the resulting pointer is not correctly aligned 68) for 
> > the referenced type, the behavior is undefined.
> > """
> 
> 
> What does 'correctly aligned' mean?

That's implementation-defined (6.2.8p1). In C2011 you can determine the
alignment of a given type under a given implementation by using
_Alignof(typename).

> Does C not allow the address of a 32-bit int to be at anything other 
> than a multiple of 4, when the machine has byte-addressed memory, even 
> when the hardware allows it?

The C standard merely allows each implementation to impose alignment
requirements for each type; each implementation is free to choose what
those requirements are. Many implementations do choose alignment
requirements greater than 1, to simplify code generation and to speed up
code execution for particular platforms.

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#67546

FromKeith Thompson <kst-u@mib.org>
Date2019-08-10 17:32 -0700
Message-ID<lna7cg8rt6.fsf@kst-u.example.com>
In reply to#67541
James Kuyper <jameskuyper@alumni.caltech.edu> writes:
> On Saturday, August 10, 2019 at 6:23:16 PM UTC-4, Bart wrote:
>> On 10/08/2019 22:46, David Brown wrote:
> ...
>> > 6.3.2.3p7:
>> > """
>> > A pointer to an object type may be converted to a pointer to a different 
>> > object type. If the resulting pointer is not correctly aligned 68) for 
>> > the referenced type, the behavior is undefined.
>> > """
>> 
>> What does 'correctly aligned' mean?
>
> That's implementation-defined (6.2.8p1). In C2011 you can determine the
> alignment of a given type under a given implementation by using
> _Alignof(typename).

There is a possibly useful distinction that this doesn't capture.

For example, on my x86_64 system, gcc has sizeof (int) == 4
and _Alignof (int) == 4.  The compiler will, in the absence of
implementation-specific directives, align int objects at 4-byte
boundaries, and any attempt to access an int object that's not
4-byte aligned has undefined behavior.

But you can successfully access int objects at odd addresses,
though doing so is likely to be less efficient (but probably more
efficient than accessing it a byte at a time).  (Possibly compiler
optimizations might result in surprising and misbehaving code in
such cases.)

Would it be useful to be able to query both the alignment at which
objects will be allocated and the (possibly smaller) alignment at
which objects can be accessed without going kaboom?

[...]

-- 
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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#67557

FromDavid Brown <david.brown@hesbynett.no>
Date2019-08-11 15:41 +0200
Message-ID<qip5ut$l9e$1@dont-email.me>
In reply to#67539
On 11/08/2019 00:22, Bart wrote:
> On 10/08/2019 22:46, David Brown wrote:
>> On 10/08/2019 17:21, Bonita Montero wrote:
>>>> More importantly here, it also does not mean you can take pointers
>>>> to  the unaligned members and use them as normal pointers, ...
>>>
>>> Quote the part of the standard that says that.
>>
>> I already did.
>>
>> These are from N1570, draft of C11 standard - C++ inherits this from C 
>> and the C standards are simpler.
>>
>> 6.3.2.3p7:
>> """
>> A pointer to an object type may be converted to a pointer to a 
>> different object type. If the resulting pointer is not correctly 
>> aligned 68) for the referenced type, the behavior is undefined.
>> """
> 
> 
> What does 'correctly aligned' mean?
> 
> Does C not allow the address of a 32-bit int to be at anything other 
> than a multiple of 4, when the machine has byte-addressed memory, even 
> when the hardware allows it?
> 

The alignment for any given type is determined by the implementation, 
which will base it on the target platform's common ABI.  Typically, 
alignment is based on the size of the type (4-byte types have 4-byte 
alignment, etc.) but reduced if the maximum access size for the cpu is 
smaller.  Thus on a 16-bit target, any type 16-bit or bigger is likely 
to be 2 byte aligned.  On a 32-bit machine, 16-bit types will be 2-byte 
aligned and 32-bit types will be 4-byte aligned.  There is some 
variation - on a 32-bit machine, you might find that 8-byte doubles are 
8-byte aligned, but they might be 4-byte aligned.

With that alignment decision made, the C standard explicitly says that 
conversions to pointers that result in them being unaligned, are 
undefined behaviour - as is dereferencing unaligned pointers.  A C 
implementation can, of course, give a definition for how it treats 
unaligned pointers - but if it does not, then you have to assume that 
they are simply not allowed.

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#67559

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-11 15:55 +0200
Message-ID<qip6p1$bk$1@news.albasani.net>
In reply to#67557
> With that alignment decision made, the C standard explicitly says
> that  conversions to pointers that result in them being unaligned,
> are  undefined behaviour - ...

Hey, are you still that stupid? We were talking about implementations
with specific support for #pragma pack! On these implementations it
is perfectly legal to take an adress of an unaligned member and such
pointers are indistinguishable from any other unaligned pointer. So
an implemtation that has support for #pragma pack must generally
support unaligned accesses.

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#67561

FromDavid Brown <david.brown@hesbynett.no>
Date2019-08-11 18:06 +0200
Message-ID<qipees$3k3$1@dont-email.me>
In reply to#67559
On 11/08/2019 15:55, Bonita Montero wrote:
>> With that alignment decision made, the C standard explicitly says
>> that  conversions to pointers that result in them being unaligned,
>> are  undefined behaviour - ...
> 
> Hey, are you still that stupid? We were talking about implementations
> with specific support for #pragma pack! On these implementations it
> is perfectly legal to take an adress of an unaligned member 

Reference?

> and such
> pointers are indistinguishable from any other unaligned pointer. 

Reference?

> So
> an implemtation that has support for #pragma pack must generally
> support unaligned accesses.

Reference?


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#67562

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-11 18:15 +0200
Message-ID<qipevq$ahj$1@news.albasani.net>
In reply to#67561
>>> With that alignment decision made, the C standard explicitly says
>>> that  conversions to pointers that result in them being unaligned,
>>> are  undefined behaviour - ...

>> Hey, are you still that stupid? We were talking about implementations
>> with specific support for #pragma pack! On these implementations it
>> is perfectly legal to take an adress of an unaligned member 

> Reference?

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.
And there must be an information that this isn't allowed in the language
-reference. So you must give the reference that this isn't allowed.
So show me this.

>> ... and such
>> pointers are indistinguishable from any other unaligned pointer. 

> Reference?

You can assign to a pointer an aligned and unaligned element on these
compilers. So the compiler can't distinguish this.

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#67564

FromDavid Brown <david.brown@hesbynett.no>
Date2019-08-11 18:59 +0200
Message-ID<qiphha$kfq$2@dont-email.me>
In reply to#67562
On 11/08/2019 18:15, Bonita Montero wrote:
>>>> With that alignment decision made, the C standard explicitly says
>>>> that  conversions to pointers that result in them being unaligned,
>>>> are  undefined behaviour - ...
> 
>>> Hey, are you still that stupid? We were talking about implementations
>>> with specific support for #pragma pack! On these implementations it
>>> is perfectly legal to take an adress of an unaligned member 
> 
>> Reference?
> 
> 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?


> And there must be an information that this isn't allowed in the language
> -reference. So you must give the reference that this isn't allowed.
> So show me this.

I've given references to say it is undefined at the language level.  If 
a compiler wants to override that and define its behaviour, fine - it 
should document it.

> 
>>> ... and such
>>> pointers are indistinguishable from any other unaligned pointer. 
> 
>> Reference?
> 
> You can assign to a pointer an aligned and unaligned element on these
> compilers. So the compiler can't distinguish this.

Again, it is all just "it worked when I tried it".

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#67565

FromBonita Montero <Bonita.Montero@gmail.com>
Date2019-08-11 19:03 +0200
Message-ID<qiphps$2f0$2@news.albasani.net>
In reply to#67564
>> 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.
But this would be clearly recognizable by the compiler and if this
would be an issue you would at least get a warning.

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