wctrans_t wctrans(const char *);
wctype_t wctype(const char *);
+#ifndef __cplusplus
#undef iswdigit
-#define iswdigit(a) (((unsigned)(a)-L'0') < 10)
+#define iswdigit(a) (0 ? iswdigit(a) : ((unsigned)(a)-'0') < 10)
+#endif
#if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
|| defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)