Race condition behaviors

[YuAo]

I think it's better to bring this discussion to an end.

I found a two years old similar post and "jonathanpenn" summarized very well, thanks jonathanpenn.

Will updating value type variable concurrently or from multiple threads cause crash?

Digging in to find how what conditions can cause crashes in these concurrent cases is laudable. It’s certainly good to understand one’s tools! But I thought it would be good to point out that Swift currently makes no guarantees about atomicity of its assignment operations. Your questions about the differences between assigning a mere primitive Int vs a complex class makes me think you might be hunting for a deeper answer. It seems to me like the questions like this often reduce to...“So, what …

This is deep down a very complex topic. I think need to do more research.