cc -pthread -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations wchar/swscanf.c -o wchar/swscanf -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv wchar/swscanf.c:5:69: error: ‘swscanf’ undeclared here (not in a function) 5 | int (*foo)(const wchar_t *restrict, const wchar_t *restrict, ...) = swscanf; | ^~~~~~~