Due to a problem in the Quartus® II software, you may see this error during the Assembler stage if your design includes a user-defined module or instance name with one of the following reserved names:
- altera_xcvr_custom
- altera_xcvr_10gbaser
- altera_xcvr_xaui
- altera_xcvr_low_latency_phy
- altera_xcvr_interlaken
- altera_xcvr_pipe
- altera_xcvr_det_latency
Due to this problem, the Quartus II software does not automatically check whether your design uses these reserved names.
To avoid this problem, do not use any of these reserved names for user-defined modules or instances.
This problem is fixed beginning with the Quartus II software version 12.1 to check whether your design uses these reserved names and issue an error instead of an internal error.