It looks like the problem is not with the trigger as such (even though it triggers the bug).
The line failing is
github.com/tbamud/tbamud/blob/master/src/dg_comm.c#L184
Code:
for (to = world[IN_ROOM(ch)].people;to; to = to->next_in_room)
To have this part of the code fail means one of two things:
- either your character is "not in a room" when doing the echoaround. This makes no sense - as a character you should always have an "in_room".
- or there's something fishy about the room list of people (world[x].people).
To check it out, when it happens next, go to the innermost frame (command is "frame 0") and studying the variables there.
Try out "print ch", "print ch->in_room", "print world[ch->in_room].people", "print world[ch->in_room].people->next_in_room", "print world[ch->in_room].people->next_in_room->next_in_room" and so on until you find the culprit (Something that gives you an error). It is likely the last "working" char you found is involved somehow.
