Making FMA more flexible

[Ty Young]

Hi all,


I'm trying to create an abstraction over the native upcall callback 
functionality of FMA. Problem is, FMA as it stands is too rigid. 
FunctionDescriptor only accepts primitive types plus MemoryAddress which 
is a problem since I don't want to have to deal with raw 
MemoryAddress(s) at the callback's end.


I've also noticed this issue with VarHandles in that it is not possible 
to quickly convert a returned MemoryAddress into something useful unless 
it's a primitive.


I think FMA needs to be a bit more flexible in this regards. Maybe 
somekind of custom serialization and deserialization functionality? I 
don't know, but I do know it's at best an annoyance and at worse a road 
blocker for abstracted callbacks.