This adds a threading library and fixes the garbage collector to work with multithreaded apps. The gc implementation is a little slow, but the functionality should be correct, and the speed can be improved.

www.digitalmars.com/d/phobos.html#thread

ftp://ftp.digitalmars.com/dmdalpha.zip

In general, you may find that dmd produces slower code than the equivalent C code. This is not an inherent problem with D, it is only that I am trying to get all the features implemented before worrying about generating optimal code for them. A major goal of D is to not sacrifice any runtime performance compared with the equivalent C.

For example, inline functions are not inlined by the current dmd alpha compiler. This is simply because I haven't written the code yet to do the inlining, it is not because inlining can't be done in D. For another example, the Phobos library is built with full debug, unittest, and contracts enabled.