- + Investigate a `robust-ABI' layout using pointers rather than simple
- inclusion. Each class's islots and vtmsgs will be found by
- following a pointer rather than just magically knowing the offsets.
- If you allocate objects dynamically, using ~CLASS->cls.initsz~
- rather than ~sizeof(CLASS__ilayout)~ then this isolates you from
- added slots and messages at all superclasses. I expect this to
- require a separate root class, but it /might/ be possible to
- mix-and-match.
+ + Implement `indirect' slots and messages, which can be added (once a
+ class has declared support) /without/ breaking the class's ABI.
+ Indirect messages can be added to an indirect `vtmsgs' structure via
+ a pointer in the main vtable. Indirect slots must be added to a
+ region of the `ilayout' located via an offset stored in the vtable.