>>>>> "B" == Bryan Murphy <bryan / terralab.com> writes: B> C++ 6.0 sp5) builds. The same code I have works fine when built with g++/gcc on my B> Linux box. Here is the quick breakdown: Like you, I can't reproduce the problem on linux. B> RBASIC(klass)->klass = rb_singleton_class_new(RBASIC(super)->klass); Can you put a breakpoint on this line, and see the content of super and klass, i.e. *(struct RClass *)super *(struct RClass *)rb_cObject *(struct RClass *)klass Guy Decoux