Re: How does inheritance and vtables work wrt. C++ and interop with D? Fns w/ Multiple-inheritance args impossible to bind to?

[evilrat via Digitalmars-d-learn]

On Tuesday, 25 May 2021 at 17:52:14 UTC, Gavin Ray wrote:

```d
void main()
{
  Derived dlangDerived = new Derived(123);
  printf("[D] Derived.Base1::getSomething() = %d \n", 
dlangDerived.getSomething());
  printf("[D] Derived.Base2::getOtherThing() = %d \n", 
dlangDerived.getOtherThing());
  printf("[D] Derived.Base1::inheritedFunctionWithArgs(5, 10) = 
%d \n",
      dlangDerived.inheritedFunctionWithArgs(5, 10));
  printf("[D] Calling C++ takesADerived() with D Derived* \n");
  takesADerived(dlangDerived);
}
```
![output](https://i.imgur.com/Plbtlow.png)


That last one with someInt is what I warned about. D ctor messed 
up class layout, in this simple case where class data isn't used 
it almost works, but will be practically unusable in real 
scenarios.