[flang-commits] [flang] [flang] Enclose Walk overloads into class for lookup purposes (PR #115926)

[Krzysztof Parzyszek via flang-commits]

kparzysz wrote:

> > > what is broken that this patch fixes?
> > > I'm trying to add more nodes for OpenMP, and when I have a variant inside of a tuple, the visitor breaks.
> 
> How does it break? Can it be fixed with a smaller change?

It fails to compile, because the call to `Walk` from `ForEachInTuple` can't use the `UnionTrait` overload.

It could be remedied with just adding a declaration for the variant overload, but the actual fix would be either using a class, or declaring all the overloads ahead of the definitions.

https://github.com/llvm/llvm-project/pull/115926