Compiling a mixed D and C++ project?

[Exil]

On Monday, 2 September 2019 at 13:51:11 UTC, Kyle De'Vir wrote:
> On Monday, 2 September 2019 at 13:32:40 UTC, a11e99z wrote:
>> https://dlang.org/spec/cpp_interface.html
>
> That doesn't help me, sadly:
>
> I compile the C++ object, but when attempting to compile with
> `dmd Main.d TestApplication.o -L-lstdc++`, I get this error:
>
>
> https://invent.kde.org/snippets/428

You have to link to Qt's libs when you are compiling your D code. 
Otherwise it won't know where to find those functions.