+ int result = 0;
+ /* Test whether the function supports a NULL destination argument.
+ This fails on native Windows. */
+ if (setlocale (LC_ALL, "$LOCALE_FR") != NULL)
+ {
+ const char input[] = "\337er";
+ const char *src = input;
+ mbstate_t state;
+
+ memset (&state, '\0', sizeof (mbstate_t));
+ if (mbsrtowcs (NULL, &src, 1, &state) != 3
+ || src != input)
+ result |= 1;
+ }