[glib] Avoid gcc warning about redeclaration of atexit() on MinGW

[Tor Lillqvist <tml src gnome org>]

commit 6e86c9a6aa977331c6bd47b726aaf34398a5ad37
Author: Tor Lillqvist <tml iki fi>
Date:   Tue Nov 10 01:37:13 2009 +0200

    Avoid gcc warning about redeclaration of atexit() on MinGW

 glib/gutils.h |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/glib/gutils.h b/glib/gutils.h
index 149d496..46c372c 100644
--- a/glib/gutils.h
+++ b/glib/gutils.h
@@ -287,7 +287,9 @@ void	g_atexit		(GVoidFunc    func);
  * wants the function to be called when it *itself* exits (or is
  * detached, in case the caller, too, is a DLL).
  */
+#if defined(__MINGW_H) && !defined(_STDLIB_H_)
 int atexit (void (*)(void));
+#endif
 #define g_atexit(func) atexit(func)
 #endif