Interfacing to C++ mention C++ symbols may have been stripped

[dlangBugzillaToGithub]

Richard (Rikki) Andrew Cattermole reported this on 2022-08-09T14:06:45Z

Transferred from https://issues.dlang.org/show_bug.cgi?id=23290

Description

When compiling against C++ object files, it is possible that the compiler has stripped symbols out of the object file.

For instance, if you have the following code in a cpp file:


```c++
#include <iostream>
struct Foo
{
    void print()
    {
        std::cout << "foo: " << a << ": hello from c++
";
    }

    int a;
};
```

And try to link against it when compiling with ``clang -c`` it will result in the linker error: ``undefined reference to 'Foo::print()'``.

This is worth mentioning in the docs for Interfacing to C++ page as it could be a gotcha that can lead to people spinning their wheels (it was encountered by someone on Discord).