'MAILBOX_CLIENT_DATA_VALID' undeclared (first use in this function); did you mean 'MAILBOX_CLIENT_READ_VALID'?

This error may be seen in Intel® Quartus® Prime Pro Edition Software version 21.1 during MicroC/OS-II compilation when a design is instantiated with the Mailbox Client Intel® FPGA IP in Intel® Stratix® 10 and all Intel Agilex® devices. This is because there is a naming mismatch with the Mailbox Client Interrupt MicroC/OS-II flag.

To avoid this error, change MAILBOX_CLIENT_DATA_VALID to MAILBOX_CLIENT_READ_VALID in altera_s10_mailbox_client.c; line 32.

This problem is fixed starting with the Intel® Quartus® Prime Pro Edition Software version 21.2.