Invalid memory operation during allocation with `new`

[Per Nordlöw]

On Sunday, 12 January 2020 at 13:58:25 UTC, Adam D. Ruppe wrote:
> Check all the classes created by those unittests. If any of 
> them have destructors that allocate memory in any way - 
> including calling like `writeln(this)` cuz that can call 
> toString, change that.

Thanks. So what about,

- in the short run,
   Qualifying all user-defined class destructors with `@nogc`?

- in the long run,
   Making DMD forbid GC-allocations transitively inside class 
destructors?