* libc/locale/locale.c (lc_ctype_charset): Set to "UTF-8" on Cygwin.

(lc_message_charset): Ditto.
	(loadlocale): Set charset of the "C" locale to "UTF-8" on Cygwin.
	* libc/stdlib/mbtowc_r.c (__mbtowc): Default to __utf8_mbtowc on
	Cygwin.
	* libc/stdlib/wctomb_r.c (__wctomb): Default to __utf8_wctomb on
	Cygwin.

newlib/libc/stdlib/mbtowc_r.c

@@ -9,7 +9,11 @@
 
 int (*__mbtowc) (struct _reent *, wchar_t *, const char *, size_t,
 		 const char *, mbstate_t *)
+#ifdef __CYGWIN__
+   = __utf8_mbtowc;
+#else
    = __ascii_mbtowc;
+#endif
 
 int
 _DEFUN (_mbtowc_r, (r, pwc, s, n, state),

newlib/libc/stdlib/wctomb_r.c

@@ -8,7 +8,11 @@
 
 int (*__wctomb) (struct _reent *, char *, wchar_t, const char *charset,
 		 mbstate_t *)
+#ifdef __CYGWIN__
+    = __utf8_wctomb;
+#else
     = __ascii_wctomb;
+#endif
 
 int
 _DEFUN (_wctomb_r, (r, s, wchar, state),