Please add the following code to your Ifx_Cfg.h
#ifdef MULTICORE_FREERTOS
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU0_HOOK(t) vPortSyscallHandler(t.tId)
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU1_HOOK(t) vPortSyscallHandler(t.tId)
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU2_HOOK(t) vPortSyscallHandler(t.tId)
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU3_HOOK(t) vPortSyscallHandler(t.tId)
#else
#ifndef FREERTOS_CORE
#define FREERTOS_CORE 0
#endif
#if FREERTOS_CORE == 0
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU0_HOOK(t) vPortSyscallHandler(t.tId)
#endif
#if FREERTOS_CORE == 1
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU1_HOOK(t) vPortSyscallHandler(t.tId)
#endif
#if FREERTOS_CORE == 2
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU2_HOOK(t) vPortSyscallHandler(t.tId)
#endif
#if FREERTOS_CORE == 3
#define IFX_CFG_CPU_TRAP_SYSCALL_CPU3_HOOK(t) vPortSyscallHandler(t.tId)
#endif
#endif
If you need to connect the syscall trap handler with the port, as the illds install custom trap handler.