cc -O2 -pipe  -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations stdio/vfscanf.c -o stdio/vfscanf -D_POSIX_C_SOURCE=202405L  -lm -lpthread 
stdio/vfscanf.c:5:50: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Werror,-Wimplicit-int]
int (*foo)(FILE *restrict, const char *restrict, va_list) = vfscanf;
                                                 ^
                                                 int
stdio/vfscanf.c:5:7: error: incompatible function pointer types initializing 'int (*)(FILE *restrict, const char *restrict, int)' (aka 'int (*)(struct __sFILE *restrict, const char *restrict, int)') with an expression of type 'int (FILE *restrict, const char *restrict, struct __va_list_tag *)' (aka 'int (struct __sFILE *restrict, const char *restrict, struct __va_list_tag *)') [-Werror,-Wincompatible-function-pointer-types]
int (*foo)(FILE *restrict, const char *restrict, va_list) = vfscanf;
      ^                                                     ~~~~~~~
2 errors generated.