cannot cast ref to RootRef in Arc/Orc

[ringabout]

type
  Color = ref object

var x = Color()
let y = cast[RootRef](x)

errors expression cannot be cast to RootRef=ref RootObj in Arc/Orc

ref #19972

[ringabout]

It makes https://github.com/yglukhov/nimsl fail.

[ringabout]

It seems that ref object cannot cast to RootRef unless it inherits from RootObj or RootRef with arc/orc.

In this case nimsl tries to cast TableRef to RootRef, however TableRef is a final object.

[ringabout]

Workaround:

type
  Color = ref object

var x = Color()
let y = cast[pointer](x)
# use Gc_ref(y) when it is needed

[ringabout]

Workaround:

type
  Color = ref object

var x = Color()
let y = cast[pointer](x)
# use Gc_ref(y) when it is needed