Nikolay Sivov (@nsivov) commented about dlls/d2d1/device.c:
render_target->device = device; ID2D1Device1_AddRef(&render_target->device->ID2D1Device1_iface);
- factory = unsafe_impl_from_ID2D1Factory(render_target->factory);
- if (d2d_factory_is_multithreaded(factory)) {
This does not need a function, just check the type field.