Bring GDC 4.10/master up to latest 4.10 GCC snapshot.

I can't guarantee that all of this is absolutely correct, but the add_to_same_comdat_group conversion is the only one I'm not that sure about. This got things compiling again on the latest GCC 4.10 snapshot.
the two lines above here just be indented appropriately to be in line with the opening ``(``