void* pointers get corrupted: D bug or misunderstanding?

[Kagamin]

On Monday, 29 July 2019 at 12:42:37 UTC, Federico Santamorena 
wrote:
> I thought you couldn't use D things like "ref" in extern(C)

It's not recommended for proper C bindings, as interoperability 
can be tricky, so they are kept close to original C source. Also 
to port C code and examples invocation should be as close to C 
code as possible. I would say your use of UFCS with gtk functions 
is probably not a good idea, it's difficult to recognize them as 
gtk functions this way, I had a suspicion something smart is 
going on there.