• d-bugmail puremagic.com (69/69) Nov 14 2020 https://issues.dlang.org/show_bug.cgi?id=21392

d-bugmail puremagic.com writes:

https://issues.dlang.org/show_bug.cgi?id=21392

          Issue ID: 21392
           Summary: extern(C++) No support for virtual inheritance ABI
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: ibuclaw gdcproject.org

Example program
---
#include <stdio.h>

struct A {
  virtual void f2 () {};
  virtual void f3 () {};
};

struct B : virtual public A {
  virtual void f3 () {};
};

struct C : public A, public B {
  virtual void f4 () {};
};

struct D : virtual public B, virtual public C, virtual public A
{
  virtual void f2 () { };
  virtual void f3 () { printf("this = %p\n", this); }
  virtual void f4 () { };
  virtual void f5 () { };
  virtual void f6 () { };
};

D *makeD()
{
  return new D;
}

---

extern(C++, struct)
{
    interface A {
        void f2();
        void f3();
    }
    interface B : A {
        void f3();
    }
    interface C : A, B {
        void f4();
    }
    interface D : B, C, A
    {
        void f2();
        void f3();
        void f4();
        void f5();
        void f6();
    }
    D makeD();
}

int main()
{
  C c = makeD();
  (cast(B)c).f3();  // !!! SEGV !!!
  return 0;
}
---

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