Hi there!
I've patched dmd to output more complete dependency information, than it does now:
https://github.com/D-Programming-Language/dmd/pull/1839
Maybe you could have a look and comment whether you like it or what you don't like about it, so I can improve it. I hope that this pull won't rot like so many dmd pull requests, but will get merged soon. I think some discussion on the pull could help, because it signals to dmd maintainers that people care about this pull.
Thanks!
Best regards,
Robert