Thanks for this move, I will give it a try tonight!

Till then, one question: To avoid the dependency on mp_clear (which is not exposed including tommath.h) , and rather than using a throw-away Tcl_Obj as you suggested, I would like to maintain one Tcl_Obj and keep invalidating its intrep: Will TclFreeIntRep() also trigger mp_clear on a bignum Tcl_Obj, reliably?

Thank you!