Why does the DUPLICATE_HIERARCHY_DEPTH assignment is ignored when used as an altera_attribute? - Why does the DUPLICATE_HIERARCHY_DEPTH assignment is ignored when used as an altera_attribute? Description Due to a problem in the Quartus® Prime Pro Edition Software version 19.1, the automatic register duplication by hierarchical proximity (DUPLICATE_HIERARCHY_DEPTH) may be ignored when applied with an 'altera_attribute' synthesis attribute. Resolution To work around this problem, set the DUPLICATE_HIERARCHY_DEPTH assignment in your Quartus® Prime settings file ( .qsf ). set_instance_assignment -name DUPLICATE_HIERARCHY_DEPTH -to <register_name> <num_levels> This problem is fixed beginning with the Quartus® Prime Pro Edition software version 19.4. Custom Fields values: ['novalue'] Troubleshooting 1808547180 False ['novalue'] ['FPGA Dev Tools Quartus® Prime Software Pro'] 19.4 19.1 ['Programmable Logic Devices'] ['novalue'] ['novalue'] ['novalue']