cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration uchar/mbrtoc16.c -o uchar/mbrtoc16 -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE  -lm -lpthread  -liconv
uchar/mbrtoc16.c:4:10: fatal error: 'uchar.h' file not found
    4 | #include <uchar.h>
      |          ^~~~~~~~~
1 error generated.