Issue 20000 - Casting to interfaces disallowed in @safe code

[n8sh]

Takes into account @Basile-z's warning about extern(C++).

[dlang-bot]

Thanks for your pull request, @n8sh!

Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20000	normal	Casting to interfaces disallowed in @safe code

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "master + dmd#10080"

[ghost]

You should insert "fix " to the git commit message because the issue is only referenced and not marked for auto-closing.

[ghost]

Cpp class to cpp class is not safe either. There was a related issue in DMD itself recently.

[ghost]

Maybe a little note about all of that should be added in the @safe specs.