clang -O2  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations uchar/c32rtomb.c -o uchar/c32rtomb -D_POSIX_C_SOURCE=202405L  -lm  -lintl
uchar/c32rtomb.c:1:10: fatal error: 'uchar.h' file not found
#include <uchar.h>
         ^
1 error generated.