Error while implementing fuzzy logic RPL in Contiki-2.7

Question

> make udp-client.sky TARGET=sky 
mkdir obj_sky
  CC        ../../../core/net/rime/rimeaddr.c
  CC        ../../../core/net/rime/timesynch.c
  CC        ../../../core/net/rime/rimestats.c
  CC        ../../../core/net/mac/cxmac.c
  CC        ../../../core/net/mac/xmac.c
../../../core/net/mac/xmac.c: In function ‘send_packet’:
../../../core/net/mac/xmac.c:457:7: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable]
  CC        ../../../core/net/mac/nullmac.c
  CC        ../../../core/net/mac/lpp.c
../../../core/net/mac/lpp.c: In function ‘input_packet’:
../../../core/net/mac/lpp.c:783:7: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable]
  CC        ../../../core/net/mac/frame802154.c
  CC        ../../../core/net/mac/sicslowmac.c
  CC        ../../../core/net/mac/nullrdc.c
../../../core/net/mac/nullrdc.c: In function ‘packet_input’:
../../../core/net/mac/nullrdc.c:288:12: warning: variable ‘original_dataptr’ set but not used [-Wunused-but-set-variable]
../../../core/net/mac/nullrdc.c:287:7: warning: variable ‘original_datalen’ set but not used [-Wunused-but-set-variable]
  CC        ../../../core/net/mac/nullrdc-noframer.c
  CC        ../../../core/net/mac/mac.c
  CC        ../../../core/net/mac/framer-nullmac.c
  CC        ../../../core/net/mac/framer-802154.c
  CC        ../../../core/net/mac/csma.c
  CC        ../../../core/net/mac/contikimac.c
../../../core/net/mac/contikimac.c: In function ‘powercycle’:
../../../core/net/mac/contikimac.c:386:27: warning: variable ‘t0’ set but not used [-Wunused-but-set-variable]
../../../core/net/mac/contikimac.c: In function ‘send_packet’:
../../../core/net/mac/contikimac.c:766:11: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable]
../../../core/net/mac/contikimac.c:544:11: warning: variable ‘is_reliable’ set but not used [-Wunused-but-set-variable]
  CC        ../../../core/net/mac/phase.c
  CC        ../../../core/net/rpl/rpl.c
../../../core/net/rpl/rpl.c:45:38: fatal error: net/rplfuzzy/rpl-private.h: No such file or directory
compilation terminated.
../../../Makefile.include:214: recipe for target 'obj_sky/rpl.o' failed
make: *** [obj_sky/rpl.o] Error 1
Process returned error code 2

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I want help regarding implementation of fuzzy logic on contiki-2.7 as its showing errors while implementing fuzzy logic objective function on Contiki-2.7. The above give code is the error message which was encountered during experimentation.