port.c and portmacro.h Once you fix this then just make sure FreeRTOSConfig.h configured properly and then project will compile fine. Let me know if issue persists even after making changes
port.cportmacro.h/usr/lib/gcc/arm-none-eabi/14.1.0/../../../../arm-none-eabi/bin/ld: CMakeFiles/freertos.dir/FreeRTOS/portable/GCC/ARM_CM4_MPU/port.c.o: in function `vSVCHandler_C':
/home/asraful/Code/STM32/STM32F446xx/FreeRTOS/portable/GCC/ARM_CM4_MPU/port.c:508:(privileged_functions+0x93c): undefined reference to `__syscalls_flash_start__'
/usr/lib/gcc/arm-none-eabi/14.1.0/../../../../arm-none-eabi/bin/ld: /home/asraful/Code/STM32/STM32F446xx/FreeRTOS/portable/GCC/ARM_CM4_MPU/port.c:508:(privileged_functions+0x940): undefined reference to `__syscalls_flash_end__'