Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Silicon Labs/Series1/EFM32GG11B/EFM32GG11B420F2048GQ100/CAN1/IF0IFS#0x0
Message Object Interrupt Flag Set Register
Set MESSAGE Interrupt Flag
https://github.com/cmsis-svd/cmsis-svd-data