The old linked list implementation used some wild typecasts and required
GCC option -fno-strict-aliasing to work properly. This patch fixes that.
However, we still keep the option due to other potential problems.
(Commited by Ondrej Santiago Zajicek)
WALK_LIST_DELSAFE (in ev_run_list) is not safe with regard
to deletion of next node. When some events are rescheduled
during event execution, it may lead to deletion of next
node and some events are skipped. Such skipped nodes remain
in temporary list on stack and the last of them contains
'next' pointer to stack area. When this event is later
scheduled, it damages stack area trying to remove it from
the list, which leads to random crashes with funny
backtraces :-) .