Stick a fork in it

[Walter Bright]

I'm currently working on implementing const/invariant. It's becoming 
clear that this is a pervasive change, and will cause binary 
incompatibility with existing code. I'm trying to minimize any source 
incompatibilities.

The first few iterations of const support probably will have lots of 
problems before it gets usable.

This means that dmd will have to fork into a 1.x maintenance version and 
a 2.x beta.