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Re: Linked lists, message passing

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On 2015-06-19, Morten W. Petersen <morphex@gmail.com> wrote:
> [...]
> https://github.com/morphex/smash_xml/blob/c7a6017a75021432dbdb52178800e15dd4bc0061/message.c
> [...]
> Do you see any obvious problems with what in the code above?

This part has a problem:

  struct message_linked_list *working_free = head;
  while (working_free) {
    printf("Free: %s\n", working_free->data);
    free(working_free);
    working_free = working_free->next;
  }

The statement

    working_free = working_free->next;

has undefined behaviour because the value of a pointer that refers to
space deallocated by the free() function is used.

One possible workaround would be

  struct message_linked_list *working_free = head;
  while (working_free) {
    printf("Free: %s\n", working_free->data);
    struct message_linked_list *next = working_free->next;
    free(working_free);
    working_free = next;
  }

And I would probably move this code to a separate function.

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Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-06-19 05:49 +0200
  Re: Linked lists, message passing Ike Naar <ike@iceland.freeshell.org> - 2015-06-19 06:51 +0000
    Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-06-19 09:08 +0200
      Re: Linked lists, message passing Barry Schwarz <schwarzb@dqel.com> - 2015-06-19 02:08 -0700
        Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-06-19 14:11 +0200
          Re: Linked lists, message passing raltbos@xs4all.nl (Richard Bos) - 2015-06-19 13:47 +0000
            Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-06-19 15:52 +0200
              Re: Linked lists, message passing Robert Wessel <robertwessel2@yahoo.com> - 2015-06-19 22:07 -0500
              Re: Linked lists, message passing raltbos@xs4all.nl (Richard Bos) - 2015-06-27 12:25 +0000
                Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-06-29 09:03 +0200
                Re: Linked lists, message passing raltbos@xs4all.nl (Richard Bos) - 2015-07-03 17:28 +0000
                Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-07-03 22:16 +0200
                Re: Linked lists, message passing Morris Dovey <mrdovey@iedu.com> - 2015-07-03 16:44 -0500
                Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-07-04 01:12 +0200
                Re: Linked lists, message passing Morris Dovey <mrdovey@iedu.com> - 2015-07-03 18:50 -0500
                Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-07-04 09:39 +0200
                Re: Linked lists, message passing Morris Dovey <mrdovey@iedu.com> - 2015-07-04 04:34 -0500
                Re: Linked lists, message passing Bartc <bc@freeuk.com> - 2015-07-04 11:01 +0100
                Re: Linked lists, message passing Geoff <geoff@invalid.invalid> - 2015-07-04 11:43 -0700
                Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-07-05 18:49 +0200
                Re: Linked lists, message passing Geoff <geoff@invalid.invalid> - 2015-07-05 12:30 -0700
                Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-07-05 22:39 +0200
                Re: Linked lists, message passing Geoff <geoff@invalid.invalid> - 2015-07-05 15:08 -0700
                Re: Linked lists, message passing glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-07-06 01:05 +0000
                Re: Linked lists, message passing Geoff <geoff@invalid.invalid> - 2015-07-05 23:55 -0700
                Re: Linked lists, message passing "Chris M. Thomasson" <nospam@nospam.nospam> - 2015-07-04 11:48 -0700
                Re: Linked lists, message passing Morris Dovey <mrdovey@iedu.com> - 2015-07-03 18:51 -0500
                Re: Linked lists, message passing G G <gdotone@gmail.com> - 2015-07-03 18:13 -0700
  Re: Linked lists, message passing Richard Heathfield <rjh@cpax.org.uk> - 2015-06-19 08:12 +0100
    Re: Linked lists, message passing "Morten W. Petersen" <morphex@gmail.com> - 2015-06-19 09:30 +0200
      Re: Linked lists, message passing Richard Heathfield <rjh@cpax.org.uk> - 2015-06-19 08:59 +0100
        Re: Linked lists, message passing Noob <root@127.0.0.1> - 2015-06-19 10:14 +0200
          Re: Linked lists, message passing Richard Heathfield <rjh@cpax.org.uk> - 2015-06-19 09:40 +0100
            Re: Linked lists, message passing Ian Collins <ian-news@hotmail.com> - 2015-06-20 15:14 +1200
    Re: Linked lists, message passing jacobnavia <jacob@jacob.remcomp.fr> - 2015-06-19 18:10 +0200
      Re: Linked lists, message passing Richard Heathfield <rjh@cpax.org.uk> - 2015-06-19 17:32 +0100
        Re: Linked lists, message passing Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-06-29 00:56 -0700
      Re: Linked lists, message passing Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-06-29 00:49 -0700
    Re: Linked lists, message passing Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-11 08:32 -0700

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