Weird... building with ```dmd -m64 -i main.d``` works fine.
Then, I tried calling [CreateFileW](https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilew), passing ```GENERIC_READ``` for ```[in] dwDesiredAccess```; I get this:
```main.d(7): Error: undefined identifier GENERIC_READ```. ImportC seems very brittle. :/
