[Issue 20716] Wrong code/ABI for extern(C++) interface method that returns non-POD

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=20716

--- Comment #3 from Walter Bright <bugzilla at digitalmars.com> ---
The problem here is the "adjustor thunk" generated does not take into account
the size of the hidden pointer parameter, and winds up adjusting the hidden
pointer rather than the `this` pointer.

--