Akinori MUSHA wrote: > True, and you can always ask ko1 to add a longstanding bug that's > caused by the core engine. I'm not sure that he'll like it vgs% cat b.rb def a Module.new do def foo super end end end M = a N = a class C include M end C.new.foo vgs% vgs% ./ruby -v b.rb ruby 1.9.0 (2008-05-30 revision 16708) [i686-linux] b.rb:4:in `foo': stack level too deep (SystemStackError) from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:4:in `foo' ... 7692 levels... from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:4:in `foo' from b.rb:15:in `<main>' vgs% vgs% cat b.rb class A @@a = 'A' def a=(x) @@a = x end def a @@a end end B = A.dup B.new.a = 'B' p A.new.a vgs% vgs% ./ruby -v b.rb ruby 1.9.0 (2008-05-30 revision 16708) [i686-linux] "B" vgs% There were, at least, 3 cases where ruby need to duplicate iseq, he has just removed one case. Guy Decoux