I also found another part with same issue on CAN1, the processor TM4C123GH6PM mounted on LaunchPad has 3 alternative for can0 but again CAN1 is firmly hardwired to USART0, the default port needed by debug and bootloader too...
Is possible on future version have CAN1 for this and TM4C129x available at other pin than default Boot Loader usart?