Description
Due to a problem in the Intel® Quartus® Prime Pro Edition Software v21.2, you may see this error in the Timing Analysis stage when you use the "report_cdc_viewer" command in a .sdc file.
Resolution
To work around this problem, do not use "report_cdc_viewer" in your .sdc files.
The "report_cdc_viewer" command should be used directly in the Timing Analyzer GUI.
This problem is fixed beginning with the Intel Quartus Prime Pro Edition Software v21.3.