Incompatible libphobos2.a?

[mta`chrono]

> I just built both 32&  64 bit DMD.
> The 32 bit works fine, but the 64 bit not.
>
> I always get this:
> /usr/bin/ld: skipping incompatible
> /home/anta40/Digital-Mars/dmd-dev/lib64/libphobos2.a when searching for
> -lphobos2
>

Did you compile druntime for 64 bit, too? As libphobos2.a is just an 
archive file, you're able to extract it and check if all containing objs 
are 64 bit. have a look at the linux "file" command.