Building issue of LwIP example of FreeRTOS Add-on

Hi,

I am trying to run the FreeRTOS LwIP example for ARM on my Sharc Audio Module (ADZS-SC589-MINI) board. I have followed each of the steps indicated in the user guide, but when I build the project, the CCES console shows an error message related with the redifinition of 'struct timeval'. This is what the console displays:

17:17:31 **** Incremental Build of configuration Release for project RTOSDemo_CORTEX_A5_SC589_CCES_LwlP ****
make all
'Building file: ../system/lwIP/AppSources/lwip_sysboot_task.c'
'Invoking: CrossCore ARM Bare Metal C Compiler'
arm-none-eabi-gcc -O2 -ffunction-sections -fdata-sections -DCORE0 -D__ADI_FREERTOS -DNDEBUG @includes-6362bb799ec7e8d7908d7a81766d74d7.txt -Wall -c -mproc=ADSP-SC589 -msi-revision=any -MMD -MP -MF"system/lwIP/AppSources/lwip_sysboot_task.d" -o  "system/lwIP/AppSources/lwip_sysboot_task.o" "../system/lwIP/AppSources/lwip_sysboot_task.c"
In file included from ../system/lwIP/AppSources/lwip_sysboot_task.h:10:0,
                 from ../system/lwIP/AppSources/lwip_sysboot_task.c:6:
C:/Analog Devices/lwIP_Stack-Rel2.6.0/lwip/ARM/include/lwip/sockets.h:308:8: error: redefinition of 'struct timeval'
 struct timeval {
        ^~~~~~~
In file included from c:\analog devices\crosscore embedded studio 2.9.0\arm\arm-none-eabi\arm-none-eabi\include\sys\select.h:26:0,
                 from c:\analog devices\crosscore embedded studio 2.9.0\arm\arm-none-eabi\arm-none-eabi\include\sys\types.h:68,
                 from c:\analog devices\crosscore embedded studio 2.9.0\arm\arm-none-eabi\arm-none-eabi\include\stdio.h:61,
                 from C:/Analog Devices/lwIP_Stack-Rel2.6.0/lwip/ARM/include/lwip/cc.h:44,
                 from C:/Analog Devices/lwIP_Stack-Rel2.6.0/lwip/ARM/include/lwip/lwipifce.h:21,
                 from ../system/lwIP/AppSources/lwip_sysboot_task.h:9,
                 from ../system/lwIP/AppSources/lwip_sysboot_task.c:6:
c:\analog devices\crosscore embedded studio 2.9.0\arm\arm-none-eabi\arm-none-eabi\include\sys\_timeval.h:52:8: note: originally defined here
 struct timeval {
        ^~~~~~~
make: *** [system/lwIP/AppSources/lwip_sysboot_task.o] Error 1
17:17:31 Build Finished (took 440ms)
Additionally, into the project explorer window, the adi_osal.h file has an exclamation mark and when I click twice on it, CCES shows an error message:
File not found: /RTOSDemo_CORTEX_A5_SC589_CCES_LwlP/system/osal/adi_osal.h.
Thanks.