Warning-[SIOB] Select index out of bounds. Following select index is out of declared bounds : [x:0]. In module instance: . In module :<module_name> &ltpath&gt/alt_ddrx_bank_tracking.v", 612: int_cmd_do_activate_cached[x]

VCS generates this warning when doing a functional simulation of the DDR, DDR2 and DDR3 SDRAM High Performance Controller II IP.

This warning is created from the code found in alt_ddrx_bank_tracking.v . The int_cmd_do_activate_cached is declared as 5 bit width. The variable int_cmd_do_activate_cached is sized based on CMD_QUEUE_DEPTH. So if int_cmd_do_activate_cached is 5-bit variable, then by writing int_cmd_do_activate_cached [>4] will cause the out of bound message. This is basically due to coding style, hence the warning is flagged. It will not cause a functionality change. This warning can be safely ignored.