If you get that assertion failure I guess you're trying to
execute ABC blocks at parse time, as the parser runs in
a separate thread.
Yes, this is what I was doing.
What you should be doing is defining a class like DoActionTag
(see libcore/swf/DoActionTag.h), that is a ControlTag.
ControlTag instances are executed by main thread when
the playhead enters the frame containing it.
You'll just have to register the ControlTag with the
movie_definition containing it (addControlTag, see
DoActionTag::doActionLoader)) and provide an execute()
method.
That worked. Thanks.