wint_t towlower(wint_t);
wint_t towupper(wint_t);
wctype_t wctype(const char *);
+
+#ifndef __cplusplus
#undef iswdigit
-#define iswdigit(a) ((unsigned)(a)-'0' < 10)
+#define iswdigit(a) (0 ? iswdigit(a) : ((unsigned)(a)-'0') < 10)
+#endif
#endif
#ifdef __cplusplus