Compilation error when adding lwm2m client on CHIP/matter sample

[Romain_KM]

Hi,

We are trying to add lwm2m (client) into light bulb sample (matter).

It results a redefinition of gethosname : CONFIG_LWM2M defines CONFIG_NET_SOCKETS_POSIX_NAMES and it seems that CHIP is using BSP ones.

Do you have an idea to solve that problem? 

In file included from C:/Users/Romain/Soft/ncs/zephyr/include/zephyr/posix/pthread.h:13,
                 from C:/Users/Romain/Soft/ncs/zephyr/lib/posix/pthread.c:12:
C:/Users/Romain/Soft/ncs/zephyr/include/zephyr/posix/unistd.h:38:19: error: redefinition of 'gethostname'
   38 | static inline int gethostname(char *buf, size_t len)
      |                   ^~~~~~~~~~~
In file included from C:/Users/Romain/Soft/ncs/zephyr/include/zephyr/posix/unistd.h:13,
                 from C:/Users/Romain/Soft/ncs/zephyr/include/zephyr/posix/pthread.h:13,
                 from C:/Users/Romain/Soft/ncs/zephyr/lib/posix/pthread.c:12:
C:/Users/Romain/Soft/ncs/zephyr/include/zephyr/net/socket.h:809:19: note: previous definition of 'gethostname' was here
  809 | static inline int gethostname(char *buf, size_t len)

How to reproduce : use the matter sample (light bulb) and add CONFIG_LWM2M.

Thanks for your help

[Simonr]

Hi

The LWM2M client utils library is not made for the nRF5340, but rather nRF9160-based devices, and we don't have any libraries for LWM2M on the nRF52/53 series devices at the moment. As for the error you're seeing, I need to know what version of NCS you're working with so I can test this on my end and possibly contact the development team on. 

Best regards,

Simon