The 'gdc-Ego' branch of GDC is a highly experimental branch of GDC with patches by Gregor Richards, using the the DMD 0.156 frontend. Furthermore, it has fixes to several bugs that were in GDC 0.17 which caused inconsistencies between DMD and GDC. It's experimental and has known bugs, but should allow you to compile D software that is only compatible with the latest DMD.

Download GDC-d-Ego-0.156.1.tar.bz2.