make new hdl worker fail if virtex6 primitive not built

Cannot build a new vhdl worker if the fixed_float primitive library is not prebuilt for virtex6. building a new worker shell should be independent of any target technology. If I have not built virtex6 primitives and I run
$ make new Worker=ramp.hdl Language=vhdl
The "Package" variable is not set. Assuming Package=local.
Creating worker subdirectory named ramp.hdl.
Running "make skeleton" to make initial skeleton in ramp.hdl/ramp.vhd
/home/embedded/ocpi/opencpi/ocpi/include/xxx-worker.mk:277: *** Primitive library "fixed_float" non-existent or not built for virtex6. Stop.
You should probably do: rm -r -f ramp.hdl

If I then run
$ make hdl HdlPlatforms=ml605
the virtex6 primitive library will be built. Rerunning the make new worker command (after first deleting the component hdl directory) correctly builds the skeleton