cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations locale/duplocale.c -o locale/duplocale -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv
locale/duplocale.c:5:29: error: ‘duplocale’ undeclared here (not in a function); did you mean ‘setlocale’?
    5 | locale_t (*foo)(locale_t) = duplocale;
      |                             ^~~~~~~~~
      |                             setlocale