>>>>> "C" == Christophe Poucet <christophe.poucet / gmail.com> writes: C> changing in gc.c and other places. Therefore I decided to use T_DATA with a C> struct in the data pointer. However unless I add an EXTRA field to the data C> struct that is a flag deciding whether a the data is shared or not I am not C> able to mimic the sharing behaviour. Sorry but I've not understood. You prefer modify ruby rather than add a field in a struct ? Guy Decoux