stddef.h: Define _BSD_WCHAR_T_DEFINED_ if _BSD_WCHAR_T_ gets undefined.

	* ginclude/stddef.h: Define _BSD_WCHAR_T_DEFINED_ if _BSD_WCHAR_T_
	gets undefined. For Darwin.

From-SVN: r48672

gcc/ChangeLog

+2002-01-09  Bryce McKinlay  <bryce@waitaki.otago.ac.nz>
+
+	* ginclude/stddef.h: Define _BSD_WCHAR_T_DEFINED_ if _BSD_WCHAR_T_
+	gets undefined. For Darwin.
+
 2002-01-09  Herman A.J. ten Brugge <Haj.Ten.Brugge@net.HCC.nl>
 
 	* config/c4x/c4x.h: Use PUSH_ARGS and PUSH_ROUNDING for stack passing.

gcc/ginclude/stddef.h

@@ -275,6 +275,7 @@ typedef long ssize_t;
 #ifdef _BSD_RUNE_T_
 #if !defined (_ANSI_SOURCE) && !defined (_POSIX_SOURCE)
 typedef _BSD_RUNE_T_ rune_t;
+#define _BSD_WCHAR_T_DEFINED_
 #if defined (__FreeBSD__)
 /* Why is this file so hard to maintain properly?  In constrast to
    the comment above regarding BSD/386 1.1, on FreeBSD for as long