Description
Due to a problem in the Intel® Quartus® Prime Pro Edition Software, you may see this internal error if your .qsf (quartus settings file) contains the following assignment:
set_global_assignment -name ENABLE_UNUSED_RX_CLOCK_WORKAROUND ON
Resolution
To avoid this error, remove the assignment as it is no longer supported.
To preserve any unused transceiver rx channels in your design, use the following assignment instead:
set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to <pin_name>
This problem is scheduled to be fixed in a future release of the Intel® Quartus® Prime Pro Edition Software.