General Description: The MAP DRC issues the following error message:
ERROR:MapLib:289 - DCM symbol "i_DCM" (output signal=clk_84) CLKFB is driven by an input buffer, but neither CLK0, CLK2X or CLKFX of the DCM is driving loads off-chip."
(In fact, the connectivity in the design is legal, if somewhat unconventional.) The DRC check has been modified to allow FDDR/DCM connectivity.