Creating a new derived mode

I have installed CC Mode 5.31.3 and the c-version test confirms this.  C
++,Java and JDEE modes seem to work fine but my derived Groovy mode
(which failed to fail under 5.30) now causes:

        Fatal error: assertion failed, file bytecode.c, line 1902,
        OPAQUEP (f->instructions)

        Fatal error (6).

which is a bit disconcerting for a beginner like me!

Is this sort of thing a "known feature"?

--

-- 
Russel.
====================================================
Dr Russel Winder                +44 20 7585 2200
41 Buckmaster Road              +44 7770 465 077
London SW11 1EN, UK             russel <at> russel.org.uk

-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys -- and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV