https://bugs.winehq.org/show_bug.cgi?id=57476
--- Comment #6 from Nikolay Sivov bunglehead@gmail.com --- One example is CreateCustomRenderingParams(), same method name is used in both IDWriteFactory and IDWriteFactory1. I expect midl won't be able to digest that.
Windows SDK does not provide idls for those files, and headers it does provide are not going to work with C code, that applies for Direct2D headers too.