Right now it does not compile, because it needs libphobos2.so.0, which is not provided.

So for me it doesn't compile due to LDFLAGS bits

Yes, you are right, it must be unset.
It compiles with something like:

make > ../gtkd.log

In abi_used_libs you can see

ld-linux-x86-64.so.2
libc.so.6
libdl.so.2
libgcc_s.so.1
libphobos2.so.0.
libpthread.so.0

I think that there is something wrong with phobos soname versioning.