DMD and GDC static libraries are incompatible on Linux?

[Jeremy DeHaan via D.gnu]

I'm pretty sure I already know the answer to this, however I just 
wanted to ask to make sure.

I was talking with someone the other day. They were using Linux 
and tried to link static libraries built with DMD during a build 
with GDC. I thought this would work due to both DMD and GDC using 
GCC on Linux, but GDC wouldn't find any of the symbols in the DMD 
static libraries. Is this normal?