[D-runtime] [dmd-internals] why core/thread.d and core/thread.di in druntime?

[Jonathan M Davis]

On Wednesday, January 09, 2013 19:22:43 Don Clugston wrote:
> Personally I don't think we should have any .di files in there,
> whatsoever. They just cause problems, for NO BENEFIT. We don't want
> have trade secrets we want to hide, and .di files serve no other
> purpose.
> (Please everyone, abandon any fanciful ideas that they speed
> compilation. Anybody who thinks it does, clearly hasn't done any
> profiling).

For most everything in druntime at this point, I believe that the .di files are 
simply copies of the .d files with a different extension, so there arguably 
isn't any real point to having them be .di files. But regardless, it's an 
improvement over stripping stuff like we were before, since using .di files 
really makes no sense for them. However, in the case of core.thread, it was my 
understanding that some sort of implementation hiding was _required_ for 
something (PIMPL?), but I don't know what. I haven't touched that code in ages 
and have no idea what work is being done on it.

- Jonathan M Davis