DMD Backend Long-term

[dsimcha]

What is the long-term plan for the current DMD backend?  I've noticed the
first steps towards 64-bit support were just checked in today (excitement to
the extreme).  However, the backend is under such a restrictive license (which
I understand Walter is not free to change) that it has a "bus factor" of 1.
If Walter were to stop maintaining it, noone else would be able to, if I
understand the licensing issues correctly.

Is there a chance of these licensing issues being cleared up so that the
backend can be released under a more permissive license?  If not, while I
understand Walter's decision to use a backend he was familiar with in the
beginning, it seems like we should abandon such a heavily encumbered backend
now that it needs serious work.