------- Comment #3 from jwakely dot gcc at gmail dot com 2010-01-06 10:42 ------- The linker error alone doesn't make the root cause obvious, but it's a fairly well known and well documented problem: http://www.parashift.com/c++-faq-lite/strange-inheritance.html#faq-23.10
-- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42540
