I get a non-fatal crash occurring when rebooting the mud and a fatal crash when shutting down. Here's the syslog.CRASH output.
Code:
$ doas gdb bin/circle lib/circle.core 
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This GDB was configured as "amd64-unknown-openbsd5.9"...
Core was generated by `circle'.
Program terminated with signal 10, Bus error.
Loaded symbols for /home/mud/clockwerx/bin/circle
Reading symbols from /usr/lib/libc.so.84.2...done.
Loaded symbols for /usr/lib/libc.so.84.2
Reading symbols from /usr/libexec/ld.so...done.
Loaded symbols for /usr/libexec/ld.so
#0  act (str=0x377f3f2f7c2 "$n stops following $N.", hide_invisible=1, ch=0x37a53581800, 
    obj=0x0, vict_obj=0x379fe0f8c00, type=3) at comm.c:2685
2685        if (!SENDOK(to) || (to == ch))
(gdb) bt
#0  act (str=0x377f3f2f7c2 "$n stops following $N.", hide_invisible=1, ch=0x37a53581800, 
    obj=0x0, vict_obj=0x379fe0f8c00, type=3) at comm.c:2685
#1  0x00000377f3d4c594 in stop_follower (ch=0x37a53581800) at utils.c:558
#2  0x00000377f3dca9d4 in destroy_db () at db.c:496
#3  0x00000377f3e1202d in main (argc=3, argv=0xa00f) at comm.c:363
(gdb) list
363       destroy_db();
364     
365       if (!scheck) {
366         log("Clearing other memory.");
367         free_bufpool();         /* comm.c */
368         free_player_index();    /* players.c */
369         free_messages();        /* fight.c */
370         free_text_files();      /* db.c */
371         board_clear_all();      /* boards.c */
372         free(cmd_sort_info);    /* act.informative.c */
(gdb) up
#1  0x00000377f3d4c594 in stop_follower (ch=0x37a53581800) at utils.c:558
558         act("$n stops following $N.", TRUE, ch, 0, ch->master, TO_NOTVICT);
(gdb) list
553         act("$n hates your guts!", FALSE, ch, 0, ch->master, TO_VICT);
554         if (affected_by_spell(ch, SPELL_CHARM))
555           affect_from_char(ch, SPELL_CHARM);
556       } else {
557         act("You stop following $N.", FALSE, ch, 0, ch->master, TO_CHAR);
558         act("$n stops following $N.", TRUE, ch, 0, ch->master, TO_NOTVICT);
559         act("$n stops following you.", TRUE, ch, 0, ch->master, TO_VICT);
560       }
561     
562       if (ch->master->followers->follower == ch) {  /* Head of follower-list? */
(gdb) up
#2  0x00000377f3dca9d4 in destroy_db () at db.c:496
496           stop_follower(chtmp);
(gdb) list
491       while (character_list) {
492         chtmp = character_list;
493         log("chtmp->master. %p ", chtmp->master);
494         character_list = character_list->next;
495         if (chtmp->master)
496           stop_follower(chtmp);
497         free_char(chtmp);
498       }
499     
500       /* Active Objects */
(gdb) down
#1  0x00000377f3d4c594 in stop_follower (ch=0x37a53581800) at utils.c:558
558         act("$n stops following $N.", TRUE, ch, 0, ch->master, TO_NOTVICT);
(gdb) down
#0  act (str=0x377f3f2f7c2 "$n stops following $N.", hide_invisible=1, ch=0x37a53581800, 
    obj=0x0, vict_obj=0x379fe0f8c00, type=3) at comm.c:2685
2685        if (!SENDOK(to) || (to == ch))
(gdb) list
2680        log("SYSERR: no valid target to act()!");
2681        return NULL;
2682      }
2683    
2684      for (; to; to = to->next_in_room) {
2685        if (!SENDOK(to) || (to == ch))
2686          continue;
2687        if (hide_invisible && ch && !CAN_SEE(to, ch))
2688          continue;
2689        if (type != TO_ROOM && to == vict_obj)
(gdb) print
The history is empty.
(gdb) up
#1  0x00000377f3d4c594 in stop_follower (ch=0x37a53581800) at utils.c:558
558         act("$n stops following $N.", TRUE, ch, 0, ch->master, TO_NOTVICT);
(gdb) print
The history is empty.
(gdb) up
#2  0x00000377f3dca9d4 in destroy_db () at db.c:496
496           stop_follower(chtmp);
(gdb) print
The history is empty.
(gdb) up 
#3  0x00000377f3e1202d in main (argc=3, argv=0xa00f) at comm.c:363
363       destroy_db();
(gdb) print
The history is empty.
(gdb) up
Initial frame selected; you cannot go up.
(gdb)