Improve interop with C's union types

[densh]

Currently it's possible to use C structs that have union members through definition of multiple variants of the same struct and casting between them. This is a bit sub-optimal from the boilerplate point of view and it would be nice to have something more user friendly in this area.

[IbrahimaWane]

Hello,
I am currently facing this issue; where I need to create a struct with a union as a member. Can you please provide a code of what you're describing above?
Thanks in advance

[densh]

@IbrahimaWane Have you had a look at https://github.com/scala-native/scala-native-bindgen, otherwise feel free to drop by our gitter and we'll figure out a good mapping for your use case.

[IbrahimaWane]

Great!
Finally, I understood the concept of the binding generator - I had some difficulties.
I hope I will be able to use it properly.
Thank you

[IbrahimaWane]

Actually, I have encountered an issue. It seems to be the same as #555.
This is the thrown error:
[error] scala.scalanative.util.UnsupportedException: can't cast from Array(Byte,2) to Array(Class(Top(java.lang.Object)),0)

This is the struct generated by bindgen :

type struct_odbsys = native.CStruct7[native.CShort, native.CArray[native.CChar, native.Nat._2], native.CArray[native.CChar, native.Nat._2], native.CArray[native.CChar, native.Nat._2], native.CArray[native.CChar, native.Nat._4], native.CArray[native.CChar, native.Nat._4], native.CArray[native.CChar, native.Nat._2]]

In my code I pass the type, ODBSYS, surrounded by a Ptr[ ].

Do you have any suggestions?
Thanks