I just updated my current sources and did a buildworld and buildkernel. This warning was spit out, although it didn't result in buildkernel failing:
In file included from /usr/src/sys/teken/teken.c:70: /usr/src/sys/teken/teken_wcwidth.h:128:1: warning: unused function 'teken_utf8_bytes_to_codepoint' [-Wunused-function] teken_utf8_bytes_to_codepoint(uint8_t bytes[4], int nbytes) ^ 1 warning generated. Just FYI. -- Gary Jennejohn