[dmd-internals] Create a dmd-cxx branch on dlang/dmd

[Iain Buclaw via dmd-internals]

Hi,

What I see as a technical/design blocker for GDC being able to move
forward to being self hosted is that I do not want to maintain two
versions of the compiler "glue".  The change between one and the other
should be seamless.

To tackle this, I've been backporting regression fixes from D to C++,
and aligning the interfaces up so that C++ headers are (almost)
identical between GDC and DMD/stable.  I would however like to do this
on a more public platform that internally within GDC.

The idea is similar to the dmd-1.x branch.  I am happy to maintain
this as a continuation of the C++ implementation, and strive to be as
close to the current spec as possible, whilst also putting in big
warnings that this branch is deprecated.

Would doing such a thing be OK?

The current C++ implementation is here:

https://github.com/D-Programming-GDC/GDC/tree/master/gcc/d/dfrontend

Differences between this and upstream DMD are documented here:

https://github.com/dlang/dmd/pull/2194

Regards,
Iain.