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Groups > comp.lang.c > #399456 > unrolled thread

this girl calls c ugly

Started byfir <profesor.fir@gmail.com>
First post2026-05-27 19:53 +0200
Last post2026-05-30 11:18 +0200
Articles 20 on this page of 360 — 21 participants

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Contents

  this girl calls c ugly fir <profesor.fir@gmail.com> - 2026-05-27 19:53 +0200
    Re: this girl calls c ugly fir <profesor.fir@gmail.com> - 2026-05-27 20:15 +0200
      Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-27 18:49 -0500
        Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-28 04:53 +0000
          Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-28 02:35 -0500
            Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-28 23:32 +0000
              Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-28 20:07 -0500
          Re: this girl calls c ugly Bonita Montero <Bonita.Montero@gmail.com> - 2026-05-28 11:48 +0200
        Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-28 09:18 +0200
          Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-28 04:57 -0500
            Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-28 23:35 +0000
            Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 09:52 +0200
              Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-29 05:20 -0500
                Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-29 13:22 +0200
                  Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-29 15:16 -0500
                    Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-30 13:52 +0200
                      Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-30 14:40 +0200
                        Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-30 16:36 +0200
                      Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-30 15:48 -0500
                        Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 11:14 +0200
                          Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-31 13:25 -0500
                            Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 22:14 +0200
                Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 15:22 +0200
                Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-30 03:49 +0000
          Re: this girl calls c ugly "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-05-28 12:47 -0700
            Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 09:56 +0200
              Re: this girl calls c ugly "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-05-29 11:00 -0700
        Re: this girl calls c ugly fir <profesor.fir@gmail.com> - 2026-05-28 17:12 +0200
          Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-28 14:07 -0500
            Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-28 23:54 +0000
              Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 10:02 +0200
                Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 12:19 +0100
                  Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 14:46 +0200
                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 14:22 +0100
                      Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 17:15 +0200
                        Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-05-29 15:59 +0000
                          Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 17:12 +0100
                            Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 18:48 +0200
                              Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 19:09 +0100
                                Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 22:00 +0200
                                  Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 22:14 +0100
                            Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-29 12:09 -0700
                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 17:05 +0100
                          Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 18:34 +0200
                      Re: this girl calls c ugly tTh <tth@none.invalid> - 2026-05-29 19:29 +0200
                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 18:53 +0100
                          Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-29 12:28 -0700
                            Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 20:49 +0100
                              Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 22:03 +0200
                              Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-29 13:56 -0700
                                Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 22:54 +0100
                                  Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-29 15:52 -0700
                                    Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-05-29 20:31 -0400
                                      Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-30 02:03 +0100
                                        Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-29 19:02 -0700
                                          Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-30 12:12 +0100
                                  Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-05-30 12:29 +0000
                                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-30 13:56 +0100
                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-30 16:43 -0700
                                        Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-31 03:37 +0200
                                          Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-30 19:53 -0700
                                            Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-02 12:16 +0200
                                          Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 11:47 +0200
                                            Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-02 12:55 +0200
                                        Re: this girl calls c ugly Richard Harnden <richard.nospam@gmail.invalid> - 2026-05-31 09:12 +0100
                                          Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 11:49 +0200
                                            Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-31 11:10 +0100
                                              Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 13:18 +0200
                                                Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-05-31 10:24 -0400
                                                  Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 17:35 +0200
                                                    Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-05-31 12:46 -0400
                                                      Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 22:24 +0200
                                                        Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-05-31 18:26 -0400
                                                          Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-01 08:28 +0200
                                                    Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-31 15:54 -0700
                                                      Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-01 08:39 +0200
                                                        Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-01 02:33 -0700
                                                      Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-02 11:48 +0200
                                                        Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-06-02 06:37 -0400
                                                        Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-02 05:06 -0700
                                                          Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 16:28 +0000
                                                            Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-04 03:37 -0700
                                                              Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-04 16:31 +0000
                                                                Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 13:36 -0700
                                                                  Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-04 23:49 +0000
                                                                    Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 18:04 -0700
                                                                      Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-06 03:10 +0000
                                                                        Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-05 23:50 -0700
                                                                          Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-08 02:20 +0000
                                                                            Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-08 12:39 -0700
                                                                              Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-08 23:15 +0000
                                                                                Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-08 18:51 -0700
                                                                                  Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-09 09:46 +0000
                                                                                    Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-09 15:07 -0700
                                                                            Re: Constants and undefined behavior antispam@fricas.org (Waldek Hebisch) - 2026-06-09 01:25 +0000
                                                                              Re: Constants and undefined behavior James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-06-09 18:29 -0400
                                                                                Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-09 16:01 -0700
                                                                                  Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-10 12:36 +0000
                                                                              Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-11 16:49 +0200
                                                                                Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-11 15:20 +0000
                                                                                  Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-11 18:08 +0200
                                                                                Re: Constants and undefined behavior antispam@fricas.org (Waldek Hebisch) - 2026-06-11 16:30 +0000
                                                                                  Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-11 20:52 +0200
                                                                                    Re: Constants and undefined behavior antispam@fricas.org (Waldek Hebisch) - 2026-06-12 02:20 +0000
                                                                      Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-06 15:47 -0700
                                                                        Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-06 16:36 -0700
                                                                          Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-06 16:43 -0700
                                                                            Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-06 17:41 -0700
                                                                    Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-05 10:41 +0200
                                                                      Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-05 10:49 -0700
                                                                      Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-06 16:15 -0700
                                                                  Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-06 18:06 -0700
                                                                    Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-07 22:34 -0700
                                                                Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-08 23:05 -0700
                                                                  Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-09 10:19 +0000
                                                                    Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-09 15:12 -0700
                                                                      Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-10 14:37 +0000
                                                                        Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-10 18:30 +0000
                                                                          Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-10 14:55 -0700
                                                                            Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-10 23:32 +0000
                                                                        Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-10 14:47 -0700
                                                                          Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-11 08:56 +0200
                                                                            Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-11 11:38 +0000
                                                                              Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-11 14:05 +0200
                                                                              Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-11 15:38 -0700
                                                                                Re: Constants and undefined behavior scott@slp53.sl.home (Scott Lurndal) - 2026-06-11 23:07 +0000
                                                                                  Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-11 17:43 -0700
                                                                                Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-12 02:02 +0000
                                                                            Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-11 17:34 +0200
                                                                              Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-12 10:58 +0200
                                                                                Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-12 12:27 -0700
                                                                            Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-11 13:29 -0700
                                                                              Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-12 02:08 +0000
                                                                              Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-12 11:02 +0200
                                                                        Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-11 17:45 +0200
                                                                    Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-10 15:11 -0700
                                                                      Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-10 22:44 +0000
                                                                        Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-10 16:19 -0700
                                                                          Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-11 11:50 +0000
                                                                            Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-11 16:28 -0700
                                                                              Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-11 23:46 +0000
                                                                                Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-11 18:29 -0700
                                                                                  Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-12 01:54 +0000
                                                                                Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-12 11:37 +0200
                                                        Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-02 05:35 -0700
                                                          Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-02 06:29 -0700
                                                            Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-02 16:10 +0200
                                                            Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-02 15:29 -0700
                                                              Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-05 06:41 -0700
                                                                Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-05 11:24 -0700
                                                                  Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-08 08:35 -0700
                                                                    Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-08 17:33 +0000
                                                                      Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-09 00:54 -0700
                                                                        Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-09 10:08 +0000
                                                                    Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-08 13:40 -0700
                                                                  Meaning of "expression" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-08 14:05 -0700
                                                                    Expression statements (was Re: Meaning of "expression") Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-09 15:17 +0200
                                                                      Re: Expression statements (was Re: Meaning of "expression") Bart <bc@freeuk.com> - 2026-06-09 14:53 +0100
                                                                        Re: Expression statements (was Re: Meaning of "expression") Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-09 16:30 +0200
                                                                          Re: Expression statements (was Re: Meaning of "expression") David Brown <david.brown@hesbynett.no> - 2026-06-09 17:13 +0200
                                                                            Re: Expression statements (was Re: Meaning of "expression") Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-09 15:34 -0700
                                                                              Re: Expression statements (was Re: Meaning of "expression") David Brown <david.brown@hesbynett.no> - 2026-06-10 09:04 +0200
                                                                                Re: Expression statements (was Re: Meaning of "expression") Bart <bc@freeuk.com> - 2026-06-10 11:10 +0100
                                                                                  Re: Expression statements (was Re: Meaning of "expression") David Brown <david.brown@hesbynett.no> - 2026-06-10 13:29 +0200
                                                                                Re: Expression statements (was Re: Meaning of "expression") Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-10 03:17 -0700
                                                                                  Re: Expression statements (was Re: Meaning of "expression") David Brown <david.brown@hesbynett.no> - 2026-06-10 13:43 +0200
                                                                                Re: Expression statements (was Re: Meaning of "expression") Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-10 14:08 -0700
                                                                                  Re: Expression statements (was Re: Meaning of "expression") David Brown <david.brown@hesbynett.no> - 2026-06-11 09:10 +0200
                                                                                Re: Expression statements (was Re: Meaning of "expression") Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-11 20:29 +0200
                                                                                  Re: Expression statements (was Re: Meaning of "expression") David Brown <david.brown@hesbynett.no> - 2026-06-12 12:55 +0200
                                                                              Re: Expression statements (was Re: Meaning of "expression") Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-11 20:12 +0200
                                                                                Re: Expression statements (was Re: Meaning of "expression") James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-06-11 15:13 -0400
                                                                                  Re: Expression statements (was Re: Meaning of "expression") Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-12 00:37 +0200
                                                                                    Re: Expression statements (was Re: Meaning of "expression") scott@slp53.sl.home (Scott Lurndal) - 2026-06-11 23:05 +0000
                                                                                      Re: Expression statements (was Re: Meaning of "expression") Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-12 01:18 +0200
                                                                                    Re: Expression statements (was Re: Meaning of "expression") Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-11 17:41 -0700
                                                                                    Re: Expression statements (was Re: Meaning of "expression") James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-06-11 20:41 -0400
                                                                        Re: Expression statements (was Re: Meaning of "expression") tTh <tth@none.invalid> - 2026-06-09 19:27 +0200
                                                                          Re: Expression statements (was Re: Meaning of "expression") Bart <bc@freeuk.com> - 2026-06-09 19:19 +0100
                                                                      Re: Expression statements (was Re: Meaning of "expression") Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-09 15:22 -0700
                                                                Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-06 03:22 +0000
                                                                  Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-05 23:56 -0700
                                                                    Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-07 13:37 +0000
                                                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-07 15:09 -0700
                                                                        Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-08 02:33 +0000
                                                                  Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-08 00:16 -0700
                                                                    Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-08 12:41 +0000
                                                                      Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-08 17:37 +0000
                                                                      Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-09 16:05 +0200
                                                      Re: this girl calls c ugly "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-06-02 13:59 -0700
                                              Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 13:05 +0000
                                                Parentheses (was: this girl calls c ugly) Bart <bc@freeuk.com> - 2026-06-02 14:38 +0100
                                                  Re: Parentheses (was: this girl calls c ugly) cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 15:19 +0000
                                                  Re: Parentheses antispam@fricas.org (Waldek Hebisch) - 2026-06-03 22:30 +0000
                                                    Re: Parentheses Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-03 16:24 -0700
                                                      Re: Parentheses antispam@fricas.org (Waldek Hebisch) - 2026-06-04 02:03 +0000
                                                    Re: Parentheses Bart <bc@freeuk.com> - 2026-06-04 01:12 +0100
                                                      Re: Parentheses antispam@fricas.org (Waldek Hebisch) - 2026-06-04 01:58 +0000
                                                        Re: Parentheses Bart <bc@freeuk.com> - 2026-06-04 11:37 +0100
                                                      Re: Parentheses cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-04 10:51 +0000
                                                        Re: Parentheses Bart <bc@freeuk.com> - 2026-06-04 12:47 +0100
                                                          Re: Parentheses Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-04 14:57 +0200
                                                          Re: Parentheses cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-04 14:31 +0000
                                                [OT] Fancy graphics (was Re: this girl calls c ugly) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-02 15:54 +0200
                                                  Re: [OT] Fancy graphics (was Re: this girl calls c ugly) Bart <bc@freeuk.com> - 2026-06-02 15:19 +0100
                                                  Re: [OT] Fancy graphics (was Re: this girl calls c ugly) cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 15:19 +0000
                                                    Re: [OT] Fancy graphics (was Re: this girl calls c ugly) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-02 17:39 +0200
                                                      Re: [OT] Fancy graphics (was Re: this girl calls c ugly) cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 16:36 +0000
                                                        Re: [OT] Fancy graphics (was Re: this girl calls c ugly) scott@slp53.sl.home (Scott Lurndal) - 2026-06-02 21:33 +0000
                                                          Re: [OT] Fancy graphics (was Re: this girl calls c ugly) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-06-02 14:43 -0700
                                                    Re: [OT] Fancy graphics (was Re: this girl calls c ugly) ram@zedat.fu-berlin.de (Stefan Ram) - 2026-06-02 17:08 +0000
                                                      Re: [OT] Fancy graphics (was Re: this girl calls c ugly) cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 19:19 +0000
                                                      Re: [OT] Fancy graphics (was Re: this girl calls c ugly) Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-06-04 00:11 +0000
                                                    Re: [OT] Fancy graphics (was Re: this girl calls c ugly) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-02 15:39 -0700
                                                      Re: [OT] Fancy graphics (was Re: this girl calls c ugly) cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-03 13:14 +0000
                                                Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-02 15:10 +0000
                                                  Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 15:31 +0000
                                            Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-05-31 10:15 -0400
                                              Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 16:29 +0200
                                          Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-31 03:45 -0700
                                            Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-31 04:02 -0700
                                          Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-05-31 09:04 -0700
                                            Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-31 18:11 +0100
                                              Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-05-31 19:34 +0000
                                              Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-05-31 19:10 -0700
                                                Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-01 11:12 +0100
                                                  Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-01 12:36 +0200
                                                  Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-01 14:26 -0700
                                                  Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-04 02:34 -0700
                                                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 12:40 +0100
                                                      Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-04 14:35 +0200
                                                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 14:18 +0100
                                                          Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-04 15:47 +0200
                                                            Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-04 15:57 +0200
                                                          Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-04 16:27 +0200
                                                            Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 16:46 +0100
                                                              Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-04 20:15 +0200
                                                              Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-04 20:54 +0200
                                                                Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 20:29 +0100
                                                                  Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 14:06 -0700
                                                                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 22:47 +0100
                                                                      Famous (hopefully last) words [on this topic] Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-05 00:27 +0200
                                                                        Re: Famous (hopefully last) words [on this topic] Bad Post <invalid@invalid.invalid> - 2026-06-05 01:20 +0100
                                                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 16:09 -0700
                                                                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-05 00:44 +0100
                                                                          Re: this girl calls c ugly "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-06-04 17:26 -0700
                                                                            Re: this girl calls c ugly antispam@fricas.org (Waldek Hebisch) - 2026-06-05 12:58 +0000
                                                                              Re: this girl calls c ugly "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-06-05 14:27 -0700
                                                                      Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-05 02:47 +0000
                                                                        Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-05 00:53 -0700
                                                                          Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-05 11:04 +0100
                                                                            Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-05 05:34 -0700
                                                                              Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-06 03:45 +0000
                                                                            Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-06 03:44 +0000
                                                                              Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-06 07:39 +0200
                                                                  Re: this girl calls c ugly "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-06-04 15:25 -0700
                                                                  Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-05 09:29 +0200
                                                                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-05 12:39 +0100
                                                                      Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-05 15:42 +0200
                                                                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-05 16:50 +0100
                                                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-05 11:09 -0700
                                                                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-05 20:29 +0100
                                                            Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-04 16:18 +0000
                                                              Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 17:23 +0100
                                                                Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-04 16:47 +0000
                                                                  Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 19:57 +0100
                                                                    Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-04 20:34 +0000
                                                                      Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-04 22:28 +0100
                                                                        Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-04 21:58 +0000
                                                                        Re: this girl calls c ugly Richard Harnden <richard.nospam@gmail.invalid> - 2026-06-04 23:25 +0100
                                                                        Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-05 02:49 +0000
                                                              Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-04 19:47 +0200
                                                                Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-04 21:04 +0200
                                                                  Re: this girl calls c ugly Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2026-06-04 19:13 +0000
                                                                    Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-05 10:34 +0200
                                                                Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 12:11 -0700
                                                                Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-06-04 16:33 -0400
                                                                  Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 14:16 -0700
                                                                    Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-05 00:02 +0000
                                                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 18:36 -0700
                                                                        Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-05 02:54 +0000
                                                                    Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-05 05:49 -0700
                                                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-05 11:01 -0700
                                                                        Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-05 11:53 -0700
                                                              Re: this girl calls c ugly Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2026-06-04 18:45 +0000
                                                                Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-04 20:19 +0000
                                                                  Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-04 20:31 +0000
                                                                    Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-04 20:41 +0000
                                                                      Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-04 20:49 +0000
                                                                        Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-05 00:03 +0000
                                                                          Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-05 00:18 +0000
                                                                            Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-05 03:02 +0000
                                                                              Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-05 14:04 +0000
                                                                                Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-06 03:49 +0000
                                                                                  Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-06 15:13 +0000
                                                                                  Re: this girl calls c ugly scott@slp53.sl.home (Scott Lurndal) - 2026-06-06 17:53 +0000
                                                          Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-04 11:59 -0700
                                                        Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-04 15:21 +0200
                                                      Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-04 06:38 -0700
                                              Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-01 09:52 +0200
                                                Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-01 02:42 -0700
                                                  Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-01 12:50 +0200
                                                Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-01 11:47 +0100
                                                  Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-01 12:55 +0200
                                                  Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-01 14:39 -0700
                                                    Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-01 15:11 -0700
                                                      Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-02 08:41 +0200
                                                        Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-02 02:07 -0700
                                                          Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-02 11:38 +0200
                                                            Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-02 05:01 -0700
                                                              It is not futile to change the subject line (Was: this girl calls c ugly) gazelle@shell.xmission.com (Kenny McCormack) - 2026-06-02 12:39 +0000
                                                                Re: It is not futile to change the subject line (Was: this girl calls c ugly) gazelle@shell.xmission.com (Kenny McCormack) - 2026-06-02 12:42 +0000
                                                          Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-02 11:46 +0200
                                                            Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-02 11:09 +0100
                                                              Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-02 05:25 -0700
                                                                Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-02 14:20 +0100
                                                                Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-02 15:12 -0700
                                                          Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-02 04:16 -0700
                                                    Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-01 15:23 -0700
                                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-01 16:06 -0700
                                                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-01 23:24 +0100
                                                      Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-02 11:35 +0200
                                                    Operator precedence in other (non-C, but "C-like") languages (Was: something about a girl) gazelle@shell.xmission.com (Kenny McCormack) - 2026-06-02 12:36 +0000
                                                Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-01 11:04 +0000
                                                  Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-01 14:04 +0200
                                                    Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-01 18:48 +0000
                                                      Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-01 21:04 +0100
                                                        Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-02 09:17 +0200
                                                      Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-02 09:09 +0200
                                                        Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-02 12:07 +0000
                                                          Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-06-02 14:37 +0200
                                                          Microcontroller software stacks (was Re: this girl calls c ugly) scott@slp53.sl.home (Scott Lurndal) - 2026-06-02 15:06 +0000
                                                      Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-04 03:58 -0700
                                                Re: this girl calls c ugly dave_thompson_2@comcast.net - 2026-06-06 19:02 -0400
                                      Re: this girl calls c ugly cross@spitfire.i.gajendra.net (Dan Cross) - 2026-05-31 19:11 +0000
                                    Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-05-31 16:08 -0700
                                      Re: this girl calls c ugly Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-05-31 16:32 -0700
                                        Re: this girl calls c ugly Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-05-31 17:12 -0700
                          Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-30 14:07 +0200
                  Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 18:10 +0200
                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 19:18 +0100
                      Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 22:17 +0200
                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-29 21:47 +0100
                    Re: this girl calls c ugly James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-05-29 15:57 -0400
                      Re: this girl calls c ugly Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-05-29 22:34 +0200
                  Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-29 23:18 +0000
                    Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-30 01:26 +0100
                      Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-30 04:25 +0000
                        Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-30 12:01 +0100
                          Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-31 00:29 +0000
                            Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-05-31 10:59 +0100
                              Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-06-01 00:33 +0000
                                Re: this girl calls c ugly Bart <bc@freeuk.com> - 2026-06-01 02:26 +0100
                            Re: this girl calls c ugly David Brown <david.brown@hesbynett.no> - 2026-05-31 13:24 +0200
            Re: this girl calls c ugly Bonita Montero <Bonita.Montero@gmail.com> - 2026-05-29 08:09 +0200
              Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-29 04:15 -0500
                Re: this girl calls c ugly Bonita Montero <Bonita.Montero@gmail.com> - 2026-05-29 14:58 +0200
                  Re: this girl calls c ugly BGB <cr88192@gmail.com> - 2026-05-30 01:04 -0500
              Re: this girl calls c ugly Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-29 23:20 +0000
                Re: this girl calls c ugly Bonita Montero <Bonita.Montero@gmail.com> - 2026-05-30 11:18 +0200

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#399870 — Re: Constants and undefined behavior

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2026-06-10 14:47 -0700
SubjectRe: Constants and undefined behavior
Message-ID<110cm0v$116qm$2@kst.eternal-september.org>
In reply to#399864
cross@spitfire.i.gajendra.net (Dan Cross) writes:
> In article <110a34q$b2kq$2@kst.eternal-september.org>,
> Keith Thompson  <Keith.S.Thompson+u@gmail.com> wrote:
>>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>>[...]
>>> Actually, no, a reference to a function is not necessary.  A
>>> couple of years ago, a well-publicized issue in a C++ compiler a
>>> couple of years ago was something along the lines of this:
>>>
>>> ```
>>> #include <stdio.h>
>>> void foo(void);
>>> int
>>> main(void)
>>> {
>>> 	for (;;);
>>> }
>>>
>>> void
>>> foo(void)
>>> {
>>> 	printf("never called\n");
>>> }
>>> ```
>>>
>>> The result of which, when run, was to print the text "never
>>> called" and exit.  That compiler was conformant with the text
>>> of the standard.
>>[...]
>>
>>That doesn't make sense to me.  Do you have a citation to this incident,
>
> Yes: https://godbolt.org/z/d1WP4KP99
>
> There was such an outcry when this was discovered that the C++
> standard was modified to add a note explicitly allowing,
> "trivial infinite loops, which cannot be removed or reordered."
> https://eel.is/c++draft/intro.progress
>
> That change is commit 29fcc1c1fab7277d96bbd2ccd37b0c14dfd75a0e
> (https://github.com/cplusplus/draft/commit/29fcc1c1fab7277d96bbd2ccd37b0c14dfd75a0e)
> in response to P2809:
> https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/p2809r3.html

So the reason the behavior was conforming was that the behavior of
the infinite loop is undefined.  I dislike the way the C++ standard
expresses this.  It says "The implementation *may assume* that any
thread will eventually do one of the following" (emphasis added).
More on that later in the context of the similar C rule.

>>and is it relevant to C?
>
> Here's a C version with the same behavior:
>
> ```
> term% cat weird.c
> #include <stdio.h>
>
> int
> main(void)
> {
>         for (unsigned int k = 0; k != 1; k += 2)
>                 ;
> 	return 0;
> }
>
> void
> hello(void)
> {
>         printf("Hello, World!\n");
> }
> term% clang --version
> clang version 22.1.6
> Target: x86_64-pc-linux-gnu
> Thread model: posix
> InstalledDir: /usr/bin
> term% clang -Wall -pedantic -O1 -std=c23 -o weird weird.c
> term% ./weird
> Hello, World!
> term%
> ```
>
>>There is a special rule in C about implementations being allowed
>>to assume that an infinite loop terminates (N3220 6.8.6.1p4),
>
> The program above meets the criteria in sec 6.8.6.1 para 4 that
> allows an implementation to assume that the loop terminates.
> Godbolt link: https://godbolt.org/z/q46o5cYGM

Right.  ("for (;;);" in the original program does not.)

Note that the C++ special rule applies only when the condition is
equivalent to a constant `true` and the body of the loop is empty.
An implementation can "assume" that any other loop will eventually
finish.

The rule in C is (6.8.6.1p4):

    An iteration statement may be assumed by the implementation
    to terminate if its controlling expression is not a constant
    expression, and none of the following operations are performed
    in its body, controlling expression or (in the case of a for
    statement) its expression-3
        — input/output operations
        — accessing a volatile object
        — synchronization or atomic operations.

`for (;;)` is treated as having a constant controlling expression.

This covers more cases than the C++ rule.

I dislike it for most of the same reasonss.  It should be phrased
in terms of the permitted behavior of a program, not what an
implementation is allowed to "assume".

In addition to that, I dislike the whole idea.  I think it's
intended to enable optimizations, but it means that for this
contrived program:

#include <stdio.h>
int main(void) {
    bool keep_going = true;
    while (keep_going) {
        keep_going = true;
    }
    puts("never reached");
}

the implementation is allowed to "assume" that the loop eventually
terminates.  It's not clear what permissions the implementation is being
given if the assumption is violated.  I think the program could legally
print "never reached", but if violating the assumption implies undefined
behavior it could do anything.

A programmer could easily write a program similar to the above
and think that the meaning is perfectly clear, have it behave very
differently because of one obscure subclause in the standard.

>>but (a) it wouldn't apply to this case, and (b) even if it did,
>>it wouldn't imply that an implicit call to foo would be permitted.
>>I can imagine an argument that the program has undefined behavior
>>and therefore it could print "never called" or "nasal demons",
>>but I'd have to see the argument.
>
> Regehr aluded to this with his taxonomy of undefined functions.
> For a function that is always undefined (a "Type 3" function), a
> compiler is under no obligation to even produce a return
> instruction for it, and the behavior of a call to such a
> function is totally undefined.  Nothing stops it from cascading
> into whatever the linker happens to put after it.
>
> Therefore, given UB, it is not necessary to have a reference to
> some function in a program's source text in order for it to be
> executed.

Of course.  Given UB, anything can happen.  There's nothing special
about a function that's never called in that context.  It just
happens to be the way it showed up in the C++ incident.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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#399884 — Re: Constants and undefined behavior

FromDavid Brown <david.brown@hesbynett.no>
Date2026-06-11 08:56 +0200
SubjectRe: Constants and undefined behavior
Message-ID<110dm6p$17r3s$1@dont-email.me>
In reply to#399870
On 10/06/2026 23:47, Keith Thompson wrote:

> Right.  ("for (;;);" in the original program does not.)
> 
> Note that the C++ special rule applies only when the condition is
> equivalent to a constant `true` and the body of the loop is empty.
> An implementation can "assume" that any other loop will eventually
> finish.
> 
> The rule in C is (6.8.6.1p4):
> 
>      An iteration statement may be assumed by the implementation
>      to terminate if its controlling expression is not a constant
>      expression, and none of the following operations are performed
>      in its body, controlling expression or (in the case of a for
>      statement) its expression-3
>          — input/output operations
>          — accessing a volatile object
>          — synchronization or atomic operations.
> 
> `for (;;)` is treated as having a constant controlling expression.
> 
> This covers more cases than the C++ rule.
> 
> I dislike it for most of the same reasonss.  It should be phrased
> in terms of the permitted behavior of a program, not what an
> implementation is allowed to "assume".
> 
> In addition to that, I dislike the whole idea.  I think it's
> intended to enable optimizations, but it means that for this
> contrived program:
> 
> #include <stdio.h>
> int main(void) {
>      bool keep_going = true;
>      while (keep_going) {
>          keep_going = true;
>      }
>      puts("never reached");
> }
> 
> the implementation is allowed to "assume" that the loop eventually
> terminates.  It's not clear what permissions the implementation is being
> given if the assumption is violated.  I think the program could legally
> print "never reached", but if violating the assumption implies undefined
> behavior it could do anything.
> 
> A programmer could easily write a program similar to the above
> and think that the meaning is perfectly clear, have it behave very
> differently because of one obscure subclause in the standard.


The idea of all this is given in a footnote in the C standards - "This 
is intended to allow compiler transformations such as removal of empty 
loops even when termination cannot be proven."

The loop might originally have contained source code, but become empty 
through pre-processing, or from other compiler transformations (such as 
the compiler seeing that the "keep_going" variable is not volatile and 
its value is never used, so assignments to it can be elided, or moving 
other things outside the loop body).

A programmer /could/ write the "keep_going" loop you gave, and 
mistakenly believe it to be infinite.  But is it likely?  In my 
experience, infinite loops are generally very clearly written - either 
as "for (;;)" loops or "while (true)" loops - or they are the result of 
bugs in the code that accidentally run forever.  If the loop is 
accidentally infinite, the programmer will already be expecting it to 
run the code after the loop.

Equally, I don't think it is likely that compilers will often be able to 
use this rule to improve code generation - it would only help in a 
situation where the loop's controlling expression is too complicated for 
the compiler to be sure that it will terminate, but where the loop body 
ends up effectively empty.  I doubt if that turns up often in real code 
either.

So while I agree that this kind of thing can lead to curiosities and 
behaviour that seems counter-intuitive, and is popular with the "modern 
compilers are evil" crowd, I really do not see it as an issue in 
practice.  There are many other mistakes programmers can make, or UB 
that they hit accidentally - this is a drop in the ocean IMHO.


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#399894 — Re: Constants and undefined behavior

Fromcross@spitfire.i.gajendra.net (Dan Cross)
Date2026-06-11 11:38 +0000
SubjectRe: Constants and undefined behavior
Message-ID<110e6nr$pug$1@reader1.panix.com>
In reply to#399884
In article <110dm6p$17r3s$1@dont-email.me>,
David Brown  <david.brown@hesbynett.no> wrote:
>On 10/06/2026 23:47, Keith Thompson wrote:
>
>> Right.  ("for (;;);" in the original program does not.)
>> 
>> Note that the C++ special rule applies only when the condition is
>> equivalent to a constant `true` and the body of the loop is empty.
>> An implementation can "assume" that any other loop will eventually
>> finish.
>> 
>> The rule in C is (6.8.6.1p4):
>> 
>>      An iteration statement may be assumed by the implementation
>>      to terminate if its controlling expression is not a constant
>>      expression, and none of the following operations are performed
>>      in its body, controlling expression or (in the case of a for
>>      statement) its expression-3
>>          — input/output operations
>>          — accessing a volatile object
>>          — synchronization or atomic operations.
>> 
>> `for (;;)` is treated as having a constant controlling expression.
>> 
>> This covers more cases than the C++ rule.
>> 
>> I dislike it for most of the same reasonss.  It should be phrased
>> in terms of the permitted behavior of a program, not what an
>> implementation is allowed to "assume".
>> 
>> In addition to that, I dislike the whole idea.  I think it's
>> intended to enable optimizations, but it means that for this
>> contrived program:
>> 
>> #include <stdio.h>
>> int main(void) {
>>      bool keep_going = true;
>>      while (keep_going) {
>>          keep_going = true;
>>      }
>>      puts("never reached");
>> }
>> 
>> the implementation is allowed to "assume" that the loop eventually
>> terminates.  It's not clear what permissions the implementation is being
>> given if the assumption is violated.  I think the program could legally
>> print "never reached", but if violating the assumption implies undefined
>> behavior it could do anything.
>> 
>> A programmer could easily write a program similar to the above
>> and think that the meaning is perfectly clear, have it behave very
>> differently because of one obscure subclause in the standard.
>
>The idea of all this is given in a footnote in the C standards - "This 
>is intended to allow compiler transformations such as removal of empty 
>loops even when termination cannot be proven."
>
>The loop might originally have contained source code, but become empty 
>through pre-processing, or from other compiler transformations (such as 
>the compiler seeing that the "keep_going" variable is not volatile and 
>its value is never used, so assignments to it can be elided, or moving 
>other things outside the loop body).

I suspect the original intent is as you said, to support removal
of "dead" loops where the body has been optimized away, or
excised using conditional compilation.  Something like,

    #ifdef DEBUG
    #define DOTHING true
    #else
    #define DOTHING false
    #endif

        ...
        for (int i = 0; i < n; i++) {
            if (DOTHING) {
                // Something complex here...    
            }
        }

If `DEBUG` is not defined in the preprocessor, the compiler has
license to elide the entire loop as part of dead code
elimination.

>A programmer /could/ write the "keep_going" loop you gave, and 
>mistakenly believe it to be infinite.  But is it likely?  In my 
>experience, infinite loops are generally very clearly written - either 
>as "for (;;)" loops or "while (true)" loops - or they are the result of 
>bugs in the code that accidentally run forever.  If the loop is 
>accidentally infinite, the programmer will already be expecting it to 
>run the code after the loop.
>
>Equally, I don't think it is likely that compilers will often be able to 
>use this rule to improve code generation - it would only help in a 
>situation where the loop's controlling expression is too complicated for 
>the compiler to be sure that it will terminate, but where the loop body 
>ends up effectively empty.  I doubt if that turns up often in real code 
>either.
>
>So while I agree that this kind of thing can lead to curiosities and 
>behaviour that seems counter-intuitive, and is popular with the "modern 
>compilers are evil" crowd, I really do not see it as an issue in 
>practice.  There are many other mistakes programmers can make, or UB 
>that they hit accidentally - this is a drop in the ocean IMHO.

As I understand it, primarily by reading the C++ problem report,
which covers both C and C++ for background, the idea is to
guarantee forward progress for programs that make use of
threads: consider cooperatively-scheduled green threads; a
programmer who inadvertantly creates an infinite loop shouldn't
be able to starve all threads for access to the CPU.

Personally, I don't think C should be in the business of doing
such things.  But it is what it is.

	- Dan C.

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#399897 — Re: Constants and undefined behavior

FromDavid Brown <david.brown@hesbynett.no>
Date2026-06-11 14:05 +0200
SubjectRe: Constants and undefined behavior
Message-ID<110e8a8$1dh8v$2@dont-email.me>
In reply to#399894
On 11/06/2026 13:38, Dan Cross wrote:
> In article <110dm6p$17r3s$1@dont-email.me>,
> David Brown  <david.brown@hesbynett.no> wrote:
>> On 10/06/2026 23:47, Keith Thompson wrote:
>>
>>> Right.  ("for (;;);" in the original program does not.)
>>>
>>> Note that the C++ special rule applies only when the condition is
>>> equivalent to a constant `true` and the body of the loop is empty.
>>> An implementation can "assume" that any other loop will eventually
>>> finish.
>>>
>>> The rule in C is (6.8.6.1p4):
>>>
>>>       An iteration statement may be assumed by the implementation
>>>       to terminate if its controlling expression is not a constant
>>>       expression, and none of the following operations are performed
>>>       in its body, controlling expression or (in the case of a for
>>>       statement) its expression-3
>>>           — input/output operations
>>>           — accessing a volatile object
>>>           — synchronization or atomic operations.
>>>
>>> `for (;;)` is treated as having a constant controlling expression.
>>>
>>> This covers more cases than the C++ rule.
>>>
>>> I dislike it for most of the same reasonss.  It should be phrased
>>> in terms of the permitted behavior of a program, not what an
>>> implementation is allowed to "assume".
>>>
>>> In addition to that, I dislike the whole idea.  I think it's
>>> intended to enable optimizations, but it means that for this
>>> contrived program:
>>>
>>> #include <stdio.h>
>>> int main(void) {
>>>       bool keep_going = true;
>>>       while (keep_going) {
>>>           keep_going = true;
>>>       }
>>>       puts("never reached");
>>> }
>>>
>>> the implementation is allowed to "assume" that the loop eventually
>>> terminates.  It's not clear what permissions the implementation is being
>>> given if the assumption is violated.  I think the program could legally
>>> print "never reached", but if violating the assumption implies undefined
>>> behavior it could do anything.
>>>
>>> A programmer could easily write a program similar to the above
>>> and think that the meaning is perfectly clear, have it behave very
>>> differently because of one obscure subclause in the standard.
>>
>> The idea of all this is given in a footnote in the C standards - "This
>> is intended to allow compiler transformations such as removal of empty
>> loops even when termination cannot be proven."
>>
>> The loop might originally have contained source code, but become empty
>> through pre-processing, or from other compiler transformations (such as
>> the compiler seeing that the "keep_going" variable is not volatile and
>> its value is never used, so assignments to it can be elided, or moving
>> other things outside the loop body).
> 
> I suspect the original intent is as you said, to support removal
> of "dead" loops where the body has been optimized away, or
> excised using conditional compilation.  Something like,
> 
>      #ifdef DEBUG
>      #define DOTHING true
>      #else
>      #define DOTHING false
>      #endif
> 
>          ...
>          for (int i = 0; i < n; i++) {
>              if (DOTHING) {
>                  // Something complex here...
>              }
>          }
> 
> If `DEBUG` is not defined in the preprocessor, the compiler has
> license to elide the entire loop as part of dead code
> elimination.
> 

I don't know about "original intent" - I was quoting a footnote in the C 
standard, but I have not done any research like reading through the 
rationale documents.

>> A programmer /could/ write the "keep_going" loop you gave, and
>> mistakenly believe it to be infinite.  But is it likely?  In my
>> experience, infinite loops are generally very clearly written - either
>> as "for (;;)" loops or "while (true)" loops - or they are the result of
>> bugs in the code that accidentally run forever.  If the loop is
>> accidentally infinite, the programmer will already be expecting it to
>> run the code after the loop.
>>
>> Equally, I don't think it is likely that compilers will often be able to
>> use this rule to improve code generation - it would only help in a
>> situation where the loop's controlling expression is too complicated for
>> the compiler to be sure that it will terminate, but where the loop body
>> ends up effectively empty.  I doubt if that turns up often in real code
>> either.
>>
>> So while I agree that this kind of thing can lead to curiosities and
>> behaviour that seems counter-intuitive, and is popular with the "modern
>> compilers are evil" crowd, I really do not see it as an issue in
>> practice.  There are many other mistakes programmers can make, or UB
>> that they hit accidentally - this is a drop in the ocean IMHO.
> 
> As I understand it, primarily by reading the C++ problem report,
> which covers both C and C++ for background, the idea is to
> guarantee forward progress for programs that make use of
> threads: consider cooperatively-scheduled green threads; a
> programmer who inadvertantly creates an infinite loop shouldn't
> be able to starve all threads for access to the CPU.
> 
> Personally, I don't think C should be in the business of doing
> such things.  But it is what it is.
> 
> 	- Dan C.
> 

I agree there.  It is up to programmers to write useful programs - I 
don't think it makes sense for a language standard to say that programs 
have to either do something observable, or get out of the way and don't 
block something else from being useful.  But I have difficulty seeing 
that this rule in the C standards would make much real-world difference 
one way or the other.

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#399919 — Re: Constants and undefined behavior

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2026-06-11 15:38 -0700
SubjectRe: Constants and undefined behavior
Message-ID<110fddl$1pooi$1@kst.eternal-september.org>
In reply to#399894
cross@spitfire.i.gajendra.net (Dan Cross) writes:
[...]
> I suspect the original intent is as you said, to support removal
> of "dead" loops where the body has been optimized away, or
> excised using conditional compilation.  Something like,
>
>     #ifdef DEBUG
>     #define DOTHING true
>     #else
>     #define DOTHING false
>     #endif
>
>         ...
>         for (int i = 0; i < n; i++) {
>             if (DOTHING) {
>                 // Something complex here...    
>             }
>         }
>
> If `DEBUG` is not defined in the preprocessor, the compiler has
> license to elide the entire loop as part of dead code
> elimination.

I think I see what you mean, but in this particular case the loop
can be proven to terminate unless `i` is modified in the body of
the loop, and a compiler can elide the entire loop anyway.

[...]

> As I understand it, primarily by reading the C++ problem report,
> which covers both C and C++ for background, the idea is to
> guarantee forward progress for programs that make use of
> threads: consider cooperatively-scheduled green threads; a
> programmer who inadvertantly creates an infinite loop shouldn't
> be able to starve all threads for access to the CPU.
>
> Personally, I don't think C should be in the business of doing
> such things.  But it is what it is.

I agree.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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#399923 — Re: Constants and undefined behavior

Fromscott@slp53.sl.home (Scott Lurndal)
Date2026-06-11 23:07 +0000
SubjectRe: Constants and undefined behavior
Message-ID<ocHWR.151942$N9we.129907@fx16.iad>
In reply to#399919
Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>[...]
>> I suspect the original intent is as you said, to support removal
>> of "dead" loops where the body has been optimized away, or
>> excised using conditional compilation.  Something like,
>>
>>     #ifdef DEBUG
>>     #define DOTHING true
>>     #else
>>     #define DOTHING false
>>     #endif
>>
>>         ...
>>         for (int i = 0; i < n; i++) {
>>             if (DOTHING) {
>>                 // Something complex here...    
>>             }
>>         }
>>
>> If `DEBUG` is not defined in the preprocessor, the compiler has
>> license to elide the entire loop as part of dead code
>> elimination.
>
>I think I see what you mean, but in this particular case the loop
>can be proven to terminate unless `i` is modified in the body of

  ...unless 'i' or 'n' is modified in the body of

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#399932 — Re: Constants and undefined behavior

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2026-06-11 17:43 -0700
SubjectRe: Constants and undefined behavior
Message-ID<110fko8$1qf9f$3@kst.eternal-september.org>
In reply to#399923
scott@slp53.sl.home (Scott Lurndal) writes:
> Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
[...]
>>I think I see what you mean, but in this particular case the loop
>>can be proven to terminate unless `i` is modified in the body of
>
>   ...unless 'i' or 'n' is modified in the body of

Touché.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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#399940 — Re: Constants and undefined behavior

Fromcross@spitfire.i.gajendra.net (Dan Cross)
Date2026-06-12 02:02 +0000
SubjectRe: Constants and undefined behavior
Message-ID<110fpcb$jo6$1@reader1.panix.com>
In reply to#399919
In article <110fddl$1pooi$1@kst.eternal-september.org>,
Keith Thompson  <Keith.S.Thompson+u@gmail.com> wrote:
>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>[...]
>> I suspect the original intent is as you said, to support removal
>> of "dead" loops where the body has been optimized away, or
>> excised using conditional compilation.  Something like,
>>
>>     #ifdef DEBUG
>>     #define DOTHING true
>>     #else
>>     #define DOTHING false
>>     #endif
>>
>>         ...
>>         for (int i = 0; i < n; i++) {
>>             if (DOTHING) {
>>                 // Something complex here...    
>>             }
>>         }
>>
>> If `DEBUG` is not defined in the preprocessor, the compiler has
>> license to elide the entire loop as part of dead code
>> elimination.
>
>I think I see what you mean, but in this particular case the loop
>can be proven to terminate unless `i` is modified in the body of
>the loop, and a compiler can elide the entire loop anyway.

Yes.  Scott aluded to the rest; what if the actual body had set
the exit condition for the loop, and had been optimized away?

For example, given `DOTHING` as above:

	for (int i = 0; i < n; ) {
	    if (DOTHING) {
		// Something complex here...
		i++;
	    }
	}

Here, as before, the compiler is allowed to assume that the loop
_would_ terminate, and thus elide it, as before.  Of course, it
is not forced to _guarantee_ that happens because it can't solve
the halting problem.

>[...]
>
>> As I understand it, primarily by reading the C++ problem report,
>> which covers both C and C++ for background, the idea is to
>> guarantee forward progress for programs that make use of
>> threads: consider cooperatively-scheduled green threads; a
>> programmer who inadvertantly creates an infinite loop shouldn't
>> be able to starve all threads for access to the CPU.
>>
>> Personally, I don't think C should be in the business of doing
>> such things.  But it is what it is.
>
>I agree.

Yup.

It is one of the reasons C is no longer my favorite language.

	- Dan C.

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#399902 — Re: Constants and undefined behavior

FromJanis Papanagnou <janis_papanagnou+ng@hotmail.com>
Date2026-06-11 17:34 +0200
SubjectRe: Constants and undefined behavior
Message-ID<110ekic$1naub$6@dont-email.me>
In reply to#399884
On 2026-06-11 08:56, David Brown wrote:
> On 10/06/2026 23:47, Keith Thompson wrote:
>> [...]
>>
>> #include <stdio.h>
>> int main(void) {
>>      bool keep_going = true;
>>      while (keep_going) {
>>          keep_going = true;
>>      }
>>      puts("never reached");
>> }
>>
>> [...]
> 
> [...]
> 
> The loop might originally have contained source code, but become empty 
> through pre-processing, or from other compiler transformations (such as 
> the compiler seeing that the "keep_going" variable is not volatile and 
> its value is never used, so assignments to it can be elided, or moving 
> other things outside the loop body).
> 
> A programmer /could/ write the "keep_going" loop you gave, and 
> mistakenly believe it to be infinite.  But is it likely? 

I think we should not make any assumptions about the "creativity" of a
programmer ("C" or else). - Semantics should be well defined, and then
clear to the programmer.

> In my 
> experience, infinite loops are generally very clearly written - either 
> as "for (;;)" loops or "while (true)" loops - or they are the result of 
> bugs in the code that accidentally run forever.  If the loop is 
> accidentally infinite, the programmer will already be expecting it to 
> run the code after the loop.
> 
> [...]
> 
> So while I agree that this kind of thing can lead to curiosities and 
> behaviour that seems counter-intuitive, and is popular with the "modern 
> compilers are evil" crowd, I really do not see it as an issue in 
> practice.  There are many other mistakes programmers can make, or UB 
> that they hit accidentally - this is a drop in the ocean IMHO.

Languages shall be sensibly and clearly defined. For bad designs (or
bad standards) the language or standard should be blamed, and not the
critics badly and inappropriately despised as ''"modern compilers are
evil" crowd''. - Programmers are at the final end of the "food chain".
And there's a lot of horrible pits in the C-language where programmers
"made the mistake" to fall in; don't blame them, neither the ones who
silently suffer nor the ones who shout out.

Janis

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#399960 — Re: Constants and undefined behavior

FromDavid Brown <david.brown@hesbynett.no>
Date2026-06-12 10:58 +0200
SubjectRe: Constants and undefined behavior
Message-ID<110ghmv$21vi3$1@dont-email.me>
In reply to#399902
On 11/06/2026 17:34, Janis Papanagnou wrote:
> On 2026-06-11 08:56, David Brown wrote:
>> On 10/06/2026 23:47, Keith Thompson wrote:
>>> [...]
>>>
>>> #include <stdio.h>
>>> int main(void) {
>>>      bool keep_going = true;
>>>      while (keep_going) {
>>>          keep_going = true;
>>>      }
>>>      puts("never reached");
>>> }
>>>
>>> [...]
>>
>> [...]
>>
>> The loop might originally have contained source code, but become empty 
>> through pre-processing, or from other compiler transformations (such 
>> as the compiler seeing that the "keep_going" variable is not volatile 
>> and its value is never used, so assignments to it can be elided, or 
>> moving other things outside the loop body).
>>
>> A programmer /could/ write the "keep_going" loop you gave, and 
>> mistakenly believe it to be infinite.  But is it likely? 
> 
> I think we should not make any assumptions about the "creativity" of a
> programmer ("C" or else). - Semantics should be well defined, and then
> clear to the programmer.

I think the semantics of this "loops can be assumed to terminate" are 
clearly defined in the standard.  I agree that the details might not be 
known to all C programmers, but I think they are only relevant in a very 
small number of cases.

> 
>> In my experience, infinite loops are generally very clearly written - 
>> either as "for (;;)" loops or "while (true)" loops - or they are the 
>> result of bugs in the code that accidentally run forever.  If the loop 
>> is accidentally infinite, the programmer will already be expecting it 
>> to run the code after the loop.
>>
>> [...]
>>
>> So while I agree that this kind of thing can lead to curiosities and 
>> behaviour that seems counter-intuitive, and is popular with the 
>> "modern compilers are evil" crowd, I really do not see it as an issue 
>> in practice.  There are many other mistakes programmers can make, or 
>> UB that they hit accidentally - this is a drop in the ocean IMHO.
> 
> Languages shall be sensibly and clearly defined. For bad designs (or
> bad standards) the language or standard should be blamed, and not the
> critics badly and inappropriately despised as ''"modern compilers are
> evil" crowd''. - Programmers are at the final end of the "food chain".
> And there's a lot of horrible pits in the C-language where programmers
> "made the mistake" to fall in; don't blame them, neither the ones who
> silently suffer nor the ones who shout out.
> 

I agree that standards should be clear, and standards documents should 
be held accountable if they are not.  There's no doubt that the C 
standards are not perfect (Keith's "42 is not an expression" is an 
example of that).

But it is less obvious that the language should be blamed for bad 
design.  As a wise man here said, "C is what it is".  The reasons for 
design decisions might be lost to history, inappropriate for a modern 
language, or forced for compatibility reasons - but the language stands 
with the rules it has.  I don't know of anyone who uses a mainstream 
programming language for serious work and does not think at least some 
of its design decisions are bad - "bad" is highly subjective, depending 
on both the programmer and the type of work they do.  Just like for any 
programming language, if you are programming in C, then you need to be 
aware of the pitfalls of C or steer well clear of where pitfalls might be.

Ultimately, programming languages are subject to the equivalent of 
market forces - the choice of language to use for a particular task is a 
matter of weighing up what you think are the good and bad points for 
available alternatives.  As the incumbent in many situations, C of 
course has an unfair advantage - but with enough incentive, people move 
to other languages with their own benefits, disadvantages, and "bad" 
design decisions.  This is a slow process, but it is the only way forward.


As for my '"modern compilers are evil" crowd' comment, there are people 
(not anyone involved in this discussion) who really do fall into that 
camp.  I've seen people who are experienced and respected developers 
make all sorts of accusations to compiler developers, claiming they are 
only interested in high scores on synthetic benchmarks and directly 
insulting their motivations and integrity, blaming them for "breaking" 
their code that relied on the effects of some kinds of UB.  It is always 
frustrating when you have code that works fine with one compiler 
version, but using another compiler results in failure due to UB in your 
code - especially if writing correct code gives inefficient results with 
the first compiler.  And it's fine to say you'd be happier if a 
particular thing that is UB in C were not UB - but it is unreasonable to 
blame compiler developers for implementing the language as it is defined.

I am not in any way saying that critics of aspects of C (the language, 
the standards, or compiler implementations) should be dismissed or 
despised - merely that the example of loop elimination leading to UB and 
unexpected results is regularly used as "evidence" by those that hold 
extreme positions about C, despite it being very unrealistic for the 
issue to cause problems in real coding practice.


It is always best if compilers are able to warn you about problems in 
your code - such as UB - and avoid surprising results.  But I don't 
think it is practical to expect them to catch everything, and too many 
warnings will flood you with false positives.  (gcc used to have a 
warning for when code was elided - as the compiler got stronger and 
gained more optimisations, the warning was dropped because eliding code 
happened far too often to warn about.)

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#400004 — Re: Constants and undefined behavior

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2026-06-12 12:27 -0700
SubjectRe: Constants and undefined behavior
Message-ID<110hmi7$2e85g$1@kst.eternal-september.org>
In reply to#399960
David Brown <david.brown@hesbynett.no> writes:
> On 11/06/2026 17:34, Janis Papanagnou wrote:
>> On 2026-06-11 08:56, David Brown wrote:
>>> On 10/06/2026 23:47, Keith Thompson wrote:
>>>> [...]
>>>>
>>>> #include <stdio.h>
>>>> int main(void) {
>>>>      bool keep_going = true;
>>>>      while (keep_going) {
>>>>          keep_going = true;
>>>>      }
>>>>      puts("never reached");
>>>> }
>>>>
>>>> [...]
>>>
>>> [...]
>>>
>>> The loop might originally have contained source code, but become
>>> empty through pre-processing, or from other compiler
>>> transformations (such as the compiler seeing that the "keep_going"
>>> variable is not volatile and its value is never used, so
>>> assignments to it can be elided, or moving other things outside the
>>> loop body).
>>>
>>> A programmer /could/ write the "keep_going" loop you gave, and
>>> mistakenly believe it to be infinite.  But is it likely? 
>>
>> I think we should not make any assumptions about the "creativity" of
>> a programmer ("C" or else). - Semantics should be well defined, and
>> then clear to the programmer.
>
> I think the semantics of this "loops can be assumed to terminate" are
> clearly defined in the standard.  I agree that the details might not
> be known to all C programmers, but I think they are only relevant in a
> very small number of cases.

I disagree that the semantics are clearly defined.  N3220 6.8.6.1p4
is specified in terms of what an implementation may "assume", not in
terms of the semantics of the program.  One can conclude that this
means that the program has undefined behavior if the assumption is
violated, but that's not directly stated.  I don't know how many C
programmers know the standard well enough to reach that conclusion.
I'm not even 100% sure it's accurate.

The permission was added in C11 with little fanfare.  It's not
mentioned in the list of major changes in the C11 Foreword.
The cases where it applies may be rarer than I had assumed, but
it at least has the potential to break existing code that was well
defined in C99.

The rationale is to provide more opportunities for optimization,
but it's not at all clear (at least to me) that it's particularly
successful.  If cases where it can cause problems are rare, then
presumably cases where it's actually useful are rare.  (That may
be an oversimplification.)

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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#399912 — Re: Constants and undefined behavior

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2026-06-11 13:29 -0700
SubjectRe: Constants and undefined behavior
Message-ID<110f5qm$1nfih$1@kst.eternal-september.org>
In reply to#399884
David Brown <david.brown@hesbynett.no> writes:
[...]
> The idea of all this is given in a footnote in the C standards - "This
> is intended to allow compiler transformations such as removal of empty
> loops even when termination cannot be proven."
>
> The loop might originally have contained source code, but become empty
> through pre-processing, or from other compiler transformations (such
> as the compiler seeing that the "keep_going" variable is not volatile
> and its value is never used, so assignments to it can be elided, or
> moving other things outside the loop body).
>
> A programmer /could/ write the "keep_going" loop you gave, and
> mistakenly believe it to be infinite.  But is it likely?  In my
> experience, infinite loops are generally very clearly written - either
> as "for (;;)" loops or "while (true)" loops - or they are the result
> of bugs in the code that accidentally run forever.  If the loop is
> accidentally infinite, the programmer will already be expecting it to
> run the code after the loop.

How about a loop that has a non-constant condition, but that is
not expected to terminate in normal usage?

    while (! something_really_bad_happened()) {
        sleep(1);
    }
    self_destruct();

A compiler could "assume" that the loop terminates, even if
something_really_bad never happens, and that assumption could result in
a call to self_destruct().  There are probably better ways to do that,
but it's straightforward code with seemingly obvious semantics that
an implementation is permitted to make unwarrated assumptions about.

[...]

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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#399941 — Re: Constants and undefined behavior

Fromcross@spitfire.i.gajendra.net (Dan Cross)
Date2026-06-12 02:08 +0000
SubjectRe: Constants and undefined behavior
Message-ID<110fpnd$8b6$1@reader1.panix.com>
In reply to#399912
In article <110f5qm$1nfih$1@kst.eternal-september.org>,
Keith Thompson  <Keith.S.Thompson+u@gmail.com> wrote:
>David Brown <david.brown@hesbynett.no> writes:
>[...]
>> The idea of all this is given in a footnote in the C standards - "This
>> is intended to allow compiler transformations such as removal of empty
>> loops even when termination cannot be proven."
>>
>> The loop might originally have contained source code, but become empty
>> through pre-processing, or from other compiler transformations (such
>> as the compiler seeing that the "keep_going" variable is not volatile
>> and its value is never used, so assignments to it can be elided, or
>> moving other things outside the loop body).
>>
>> A programmer /could/ write the "keep_going" loop you gave, and
>> mistakenly believe it to be infinite.  But is it likely?  In my
>> experience, infinite loops are generally very clearly written - either
>> as "for (;;)" loops or "while (true)" loops - or they are the result
>> of bugs in the code that accidentally run forever.  If the loop is
>> accidentally infinite, the programmer will already be expecting it to
>> run the code after the loop.
>
>How about a loop that has a non-constant condition, but that is
>not expected to terminate in normal usage?
>
>    while (! something_really_bad_happened()) {
>        sleep(1);
>    }
>    self_destruct();
>
>A compiler could "assume" that the loop terminates, even if
>something_really_bad never happens, and that assumption could result in
>a call to self_destruct().  There are probably better ways to do that,
>but it's straightforward code with seemingly obvious semantics that
>an implementation is permitted to make unwarrated assumptions about.
>
>[...]

I think, given the names, that this would _likely_ not meet the
criteria in 6.8.6 para 4.  What would the criteria for,
`something_really_bad_happened` to return `true`?  It would
almost certainly involve something that is listed as a require
for the compiler to prove could not happen in order to assume
the loop terminates; as written, the "assume it terminates"
pretty much only allows empty loop bodies, or bodies that just
do simple calculations.  I guess it's possible, but I'm having a
hard time imagining that `something_really_bad_happened`
wouldn't do IO or access a volatile or do an atomic operation or
something. 

	- Dan C.

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#399961 — Re: Constants and undefined behavior

FromDavid Brown <david.brown@hesbynett.no>
Date2026-06-12 11:02 +0200
SubjectRe: Constants and undefined behavior
Message-ID<110ghv0$21vi3$2@dont-email.me>
In reply to#399912
On 11/06/2026 22:29, Keith Thompson wrote:
> David Brown <david.brown@hesbynett.no> writes:
> [...]
>> The idea of all this is given in a footnote in the C standards - "This
>> is intended to allow compiler transformations such as removal of empty
>> loops even when termination cannot be proven."
>>
>> The loop might originally have contained source code, but become empty
>> through pre-processing, or from other compiler transformations (such
>> as the compiler seeing that the "keep_going" variable is not volatile
>> and its value is never used, so assignments to it can be elided, or
>> moving other things outside the loop body).
>>
>> A programmer /could/ write the "keep_going" loop you gave, and
>> mistakenly believe it to be infinite.  But is it likely?  In my
>> experience, infinite loops are generally very clearly written - either
>> as "for (;;)" loops or "while (true)" loops - or they are the result
>> of bugs in the code that accidentally run forever.  If the loop is
>> accidentally infinite, the programmer will already be expecting it to
>> run the code after the loop.
> 
> How about a loop that has a non-constant condition, but that is
> not expected to terminate in normal usage?
> 
>      while (! something_really_bad_happened()) {
>          sleep(1);
>      }
>      self_destruct();
> 
> A compiler could "assume" that the loop terminates, even if
> something_really_bad never happens, and that assumption could result in
> a call to self_destruct().  There are probably better ways to do that,
> but it's straightforward code with seemingly obvious semantics that
> an implementation is permitted to make unwarrated assumptions about.
> 

The compiler can only assume that if it knows that the controlling 
expression - the call to "something_really_bad_happened()" - does not 
contain any IO operations, volatile accesses or atomic operations.

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#399903 — Re: Constants and undefined behavior

FromJanis Papanagnou <janis_papanagnou+ng@hotmail.com>
Date2026-06-11 17:45 +0200
SubjectRe: Constants and undefined behavior
Message-ID<110el6r$1nauc$7@dont-email.me>
In reply to#399864
On 2026-06-10 16:37, Dan Cross wrote:
>> [...]
> Here's a C version with the same behavior:
> 
> ```
> term% cat weird.c
> #include <stdio.h>
> 
> int
> main(void)
> {
>          for (unsigned int k = 0; k != 1; k += 2)
>                  ;
> 	return 0;
> }
> 
> void
> hello(void)
> {
>          printf("Hello, World!\n");
> }
> term% clang --version
> clang version 22.1.6
> Target: x86_64-pc-linux-gnu
> Thread model: posix
> InstalledDir: /usr/bin
> term% clang -Wall -pedantic -O1 -std=c23 -o weird weird.c
> term% ./weird
> Hello, World!
> term%
> ```

Wow, that's really fascinating! (In a bad sense.)

And (in clang) just an effect of the '-O1' (as I notice).

I may have missed the "programming language design" wisdom of the
past decades. Back then we had the conception that "optimization"
is a method to transform a program to a _functionally equivalent_
code (one that is faster, requires less memory, or some such).

Janis

> [...]

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#399872 — Re: Constants and undefined behavior

FromTim Rentsch <tr.17687@z991.linuxsc.com>
Date2026-06-10 15:11 -0700
SubjectRe: Constants and undefined behavior
Message-ID<86ldcm82ql.fsf@linuxsc.com>
In reply to#399815
cross@spitfire.i.gajendra.net (Dan Cross) writes:

> In article <86tsrc8d0b.fsf@linuxsc.com>,
> Tim Rentsch  <tr.17687@z991.linuxsc.com> wrote:
>[...]
>> The C standard doesn't need to say that, for example, a
>> function x() other than main(), whose name is never referenced,
>> will never be called.  If someone wants to establish that x() could
>> be called, there needs to be a chain of reasoning going through the
>> semantic descriptions given in the C standard, to show that a call
>> to x() could occur.
>
> Actually, no, a reference to a function is not necessary.  A
> couple of years ago, a well-publicized issue in a C++ compiler a
> couple of years ago was something along the lines of this:
> [...]

This is comp.lang.c.  My comments were only about C, and not
about C++.  But of course you already knew that.

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#399873 — Re: Constants and undefined behavior

Fromcross@spitfire.i.gajendra.net (Dan Cross)
Date2026-06-10 22:44 +0000
SubjectRe: Constants and undefined behavior
Message-ID<110cpca$gl2$1@reader1.panix.com>
In reply to#399872
In article <86ldcm82ql.fsf@linuxsc.com>,
Tim Rentsch  <tr.17687@z991.linuxsc.com> wrote:
>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>
>> In article <86tsrc8d0b.fsf@linuxsc.com>,
>> Tim Rentsch  <tr.17687@z991.linuxsc.com> wrote:
>>[...]
>>> The C standard doesn't need to say that, for example, a
>>> function x() other than main(), whose name is never referenced,
>>> will never be called.  If someone wants to establish that x() could
>>> be called, there needs to be a chain of reasoning going through the
>>> semantic descriptions given in the C standard, to show that a call
>>> to x() could occur.
>>
>> Actually, no, a reference to a function is not necessary.  A
>> couple of years ago, a well-publicized issue in a C++ compiler a
>> couple of years ago was something along the lines of this:
>> [...]
>
>This is comp.lang.c.  My comments were only about C, and not
>about C++.  But of course you already knew that.

I see you did not read the other messages in the (sub)thread,
but ok, here it is again, in C:

```
term% cat what.c
#include <stdio.h>
int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
void hello(void) { printf("Hello, World!\n"); }
term% clang --version | sed 1q
clang version 22.1.6
term% clang -Wall -pedantic -pedantic-errors -O1 -std=c23 -o what what.c
what.c:2:58: warning: for loop has empty body [-Wempty-body]
    2 | int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
      |                                                          ^
what.c:2:58: note: put the semicolon on a separate line to silence this warning
1 warning generated.
term% ./what
Hello, World!
term% 
```

	- Dan C.

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#399874 — Re: Constants and undefined behavior

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2026-06-10 16:19 -0700
SubjectRe: Constants and undefined behavior
Message-ID<110cre9$13aa9$1@kst.eternal-september.org>
In reply to#399873
cross@spitfire.i.gajendra.net (Dan Cross) writes:
[...]
> I see you did not read the other messages in the (sub)thread,
> but ok, here it is again, in C:
>
> ```
> term% cat what.c
> #include <stdio.h>
> int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
> void hello(void) { printf("Hello, World!\n"); }
> term% clang --version | sed 1q
> clang version 22.1.6
> term% clang -Wall -pedantic -pedantic-errors -O1 -std=c23 -o what what.c
> what.c:2:58: warning: for loop has empty body [-Wempty-body]
>     2 | int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
>       |                                                          ^
> what.c:2:58: note: put the semicolon on a separate line to silence this warning
> 1 warning generated.
> term% ./what
> Hello, World!
> term% 
> ```

I see the same behavior.

The following largely repeats what I've written previously in
this thread.

Apparently the authors of clang decided that this statement in N3220
6.8.6.p4:

    An iteration statement may be assumed by the implementation to
    terminate if its controlling expression is not a constant
    expression, ...

means that a program that violates that assumption has undefined
behavior.  I intensely dislike both the rule and the way it's stated,
but I agree that the conclusion that the behavior is undefined is
a reasonable one.

Of course since the behavior is undefined, *anything* could happen.
I don't know what happened inside clang (or the minds of its
maintainers) that caused it to generate code that executes a
statement in the body of a function that's never called, but that's
just one of the infinitely many allowed behaviors.  A quick look at the
generated code indicates that there's no x86-64 "retq" instruction
for either main() or hello(), and apparently control falls through
from the end of main() to the body of hello().  That seems weird.

It might just be a bug (but not one that, as far as I can tell,
violates the C standard).

A function whose body contains a construct that would have undefined
behavior if the function were called (not the case here) does not
cause undefined behavior if there are no calls to the function.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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#399896 — Re: Constants and undefined behavior

Fromcross@spitfire.i.gajendra.net (Dan Cross)
Date2026-06-11 11:50 +0000
SubjectRe: Constants and undefined behavior
Message-ID<110e7dc$s4$1@reader1.panix.com>
In reply to#399874
In article <110cre9$13aa9$1@kst.eternal-september.org>,
Keith Thompson  <Keith.S.Thompson+u@gmail.com> wrote:
>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>[...]
>> I see you did not read the other messages in the (sub)thread,
>> but ok, here it is again, in C:
>>
>> ```
>> term% cat what.c
>> #include <stdio.h>
>> int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
>> void hello(void) { printf("Hello, World!\n"); }
>> term% clang --version | sed 1q
>> clang version 22.1.6
>> term% clang -Wall -pedantic -pedantic-errors -O1 -std=c23 -o what what.c
>> what.c:2:58: warning: for loop has empty body [-Wempty-body]
>>     2 | int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
>>       |                                                          ^
>> what.c:2:58: note: put the semicolon on a separate line to silence this warning
>> 1 warning generated.
>> term% ./what
>> Hello, World!
>> term% 
>> ```
>
>I see the same behavior.
>
>The following largely repeats what I've written previously in
>this thread.
>
>Apparently the authors of clang decided that this statement in N3220
>6.8.6.p4:
>
>    An iteration statement may be assumed by the implementation to
>    terminate if its controlling expression is not a constant
>    expression, ...
>
>means that a program that violates that assumption has undefined
>behavior.  I intensely dislike both the rule and the way it's stated,
>but I agree that the conclusion that the behavior is undefined is
>a reasonable one.

I think the behavior is technical "unspecified" in the sense of
the C standard, but yes, this is the important bit.  The
controlling expresion is not constant, and the loop doesn't meet
any of the other criteria set forth in sec 6.8.6 para 4 for,
therefore, the translator may assume it terminates (it is
unspecified whether or not it does; either behavior is correct.
GCC, for example, appears not to make the same assumption).

>Of course since the behavior is undefined, *anything* could happen.
>I don't know what happened inside clang (or the minds of its
>maintainers) that caused it to generate code that executes a
>statement in the body of a function that's never called, but that's
>just one of the infinitely many allowed behaviors.  A quick look at the
>generated code indicates that there's no x86-64 "retq" instruction
>for either main() or hello(), and apparently control falls through
>from the end of main() to the body of hello().  That seems weird.

Here's a slightly better version of `what.c` (that removes the
annoying "loop is body, move the semicolon to the next line"
warning):

```
#include <stdio.h>
int main(void) { unsigned int k = 0; while (k != 1) k += 2; return 0; }
void hello(void) { printf("Hello, World!\n"); }
```

I think the reasoning goes something like this: in optimization
phase $n$, the compiler determines that `k` can never be 1, and
thus the loop does not terminate, and therefore, `return 0;` is
inaccessible, so it's removed.  Then, in phase $n + k$, for
$k>0$, it applies the rules of sec 6.8.6 para 4, assumes that
the loop must terminate, and therefore can be removed, and
removes it.  The `return` is already gone.  So what you're left
with is an label that just cascades into whatever is next in
object code; that just happens to be `hello`.

>It might just be a bug (but not one that, as far as I can tell,
>violates the C standard).

It's known.  It was known when first reported a couple of years
ago in the C++ context, and I suspect they know about it now.  I
can ask someone who works on LLVM.  I suspect the reasoning will
be that this is important to guarantee forward progress, and
that they can't solve the halting problem, therefore such loops
can be removed.  If that causes your program to do something
weird, then, well, don't do that.

>A function whose body contains a construct that would have undefined
>behavior if the function were called (not the case here) does not
>cause undefined behavior if there are no calls to the function.

True, but irrelevant to the point I was making, which is that UB
can induce a "call" to a function, even without a reference to
it appearing in the source text.

	- Dan C.

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#399925 — Re: Constants and undefined behavior

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2026-06-11 16:28 -0700
SubjectRe: Constants and undefined behavior
Message-ID<110fgbi$1qf9f$1@kst.eternal-september.org>
In reply to#399896
cross@spitfire.i.gajendra.net (Dan Cross) writes:
> In article <110cre9$13aa9$1@kst.eternal-september.org>,
> Keith Thompson  <Keith.S.Thompson+u@gmail.com> wrote:
>>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>>[...]
>>> I see you did not read the other messages in the (sub)thread,
>>> but ok, here it is again, in C:
>>>
>>> ```
>>> term% cat what.c
>>> #include <stdio.h>
>>> int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
>>> void hello(void) { printf("Hello, World!\n"); }
>>> term% clang --version | sed 1q
>>> clang version 22.1.6
>>> term% clang -Wall -pedantic -pedantic-errors -O1 -std=c23 -o what what.c
>>> what.c:2:58: warning: for loop has empty body [-Wempty-body]
>>>     2 | int main(void) { for (unsigned int k = 0; k != 1; k += 2); return 0; }
>>>       |                                                          ^
>>> what.c:2:58: note: put the semicolon on a separate line to silence this warning
>>> 1 warning generated.
>>> term% ./what
>>> Hello, World!
>>> term% 
>>> ```
>>
>>I see the same behavior.
>>
>>The following largely repeats what I've written previously in
>>this thread.
>>
>>Apparently the authors of clang decided that this statement in N3220
>>6.8.6.p4:
>>
>>    An iteration statement may be assumed by the implementation to
>>    terminate if its controlling expression is not a constant
>>    expression, ...
>>
>>means that a program that violates that assumption has undefined
>>behavior.  I intensely dislike both the rule and the way it's stated,
>>but I agree that the conclusion that the behavior is undefined is
>>a reasonable one.
>
> I think the behavior is technical "unspecified" in the sense of
> the C standard, but yes, this is the important bit.  The
> controlling expresion is not constant, and the loop doesn't meet
> any of the other criteria set forth in sec 6.8.6 para 4 for,
> therefore, the translator may assume it terminates (it is
> unspecified whether or not it does; either behavior is correct.
> GCC, for example, appears not to make the same assumption).

Why do you think the behavior is unspecified rather that undefined?

Unspecified behavior is defined as: "behavior, that results from
the use of an unspecified value, or other behavior upon which
this document provides two or more possibilities and imposes
no further requirements on which is chosen in any instance".
(Implementation-defined behavior differs from unspecified behavior
in that the implementation must document how the choice is made.)

What are the "two more more possibilities" in this case?

[SNIP]

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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