Program crash: GC destroys an object unexpectedly

[eugene]

On Sunday, 19 September 2021 at 16:27:55 UTC, jfondren wrote:
>
> This is a sufficient patch to prevent the segfault:
>
> ```
> diff --git a/echo_client.d b/echo_client.d
> index 1f8270e..5ec41df 100644
> --- a/echo_client.d
> +++ b/echo_client.d
> @@ -32,7 +32,7 @@ void main(string[] args) {
>          sm.run();
>      }
>
> -    auto stopper = new Stopper();
> +    scope stopper = new Stopper();
>      stopper.run();

I tried stack allocated stopper in my second 'simple example' 
and...
No segfault, but:
http://zed.karelia.ru/0/e/oops.png
As can be seen from the screenshot, destructors of sg0 and sg1 
were not called,
but at the very end something went completely wrong.