This is xnu-11215.1.10. See this file in: 
/*
 * Copyright (c) 2021, Apple Inc.  All rights reserved.
 * 
 * MIG server interface for memory error reporting.
 */


subsystem
#if	KERNEL_USER
    KernelUser
#endif	/* KERNEL_USER */
    memory_error_notification 5900;

#include <mach/std_types.defs>
#include <mach/mach_types.defs>

type mcc_ecc_event_t = struct[10] of uint32_t;
type ecc_event_t = struct[10] of uint32_t;

simpleroutine   memory_error_notification(
	RequestPort memory_error_port   : mach_port_t;
	in          event               : ecc_event_t;
	ServerAuditToken atoken         : audit_token_t);

simpleroutine   mcc_memory_error_notification(
	RequestPort memory_error_port   : mach_port_t;
	in          event               : mcc_ecc_event_t;
	ServerAuditToken atoken         : audit_token_t);

import <kern/ecc.h>;