cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration monetary/strfmon_l.c -o monetary/strfmon_l -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE  -lm -lpthread  -liconv
monetary/strfmon_l.c:25:7: error: call to undeclared function 'strfmon_l'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
   25 |         if ( strfmon_l(output, sizeof(output), locale,
      |              ^
monetary/strfmon_l.c:25:7: note: did you mean 'strfmon'?
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/_monetary.h:41:9: note: 'strfmon' declared here
   41 | ssize_t strfmon(char *_LIBC_COUNT(__maxsize), size_t __maxsize, const char *, ...);
      |         ^
1 error generated.