http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47845
--- Comment #2 from KePu <Kdx1999 at gmail dot com> 2011-02-22 12:54:10 UTC --- Thank you for respond this issue, I have modified the definition of vec:). But it seems that only the first argument can be set to subclass of vec, the other must be strictly set to vec, so the additional coordinate z can't be used in newly overriding procedures.
