Why does the synchronizer chain "altera_std_synchronizer_nocut" have unsafe MTBF in the metastability report in Timing Analyzer? - Why does the synchronizer chain "altera_std_synchronizer_nocut" have unsafe MTBF in the metastability report in Timing Analyzer? Description Due to a problem with the Quartus® Prime Pro Edition version 19.1, the synchronizer chain "altera_std_synchronizer_nocut" might have an unsafe Mean Time between Failure (MTBF) when it follows an asynchronous transfer. This is because the synchronizer chain is merged with retimer-created registers, which breaks the synchronizer requirements. Without a synchronizer, an asynchronous transfer will have a very low MTBF and be reported as being unsafe. Resolution To work around this problem for the Quartus® Prime Pro Edition Software, turn off the early retimer by writting the following assignment in the Quartus Settings file (.qsf): "set_global_assignment -name FITTER_EARLY_RETIMING OFF" This problem is fixed beginning with version 19.2 of the Quartus® Prime Pro Edition Software version. Custom Fields values: ['novalue'] Troubleshooting 1409335092 False ['novalue'] ['FPGA Dev Tools Quartus® Prime Software Pro'] 19.2 19.1 ['Stratix® 10 FPGAs and SoCs'] ['novalue'] ['novalue'] ['novalue']