Fix:

error: unknown type name '_GLIBCXX_BEGIN_NAMESPACE'

https://github.com/love2d/love/issues/794
https://github.com/love2d/love/commit/70996a417fe8872b813315cc50f47fe3bdf1c475
--- src/common/config.h.orig	2012-04-02 15:31:32.000000000 -0500
+++ src/common/config.h	2013-11-15 14:35:11.000000000 -0600
@@ -30,6 +30,7 @@
 #endif
 #if defined(__APPLE__)
 #	define LOVE_MACOSX 1
+#	include <AvailabilityMacros.h>
 #endif
 #if defined(macintosh)
 #	define LOVE_MACOS 1
@@ -73,7 +74,9 @@
 #endif
 
 #if defined(LOVE_MACOSX)
-#	define LOVE_LEGENDARY_LIBSTDCXX_HACK
+#	if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
+#		define LOVE_LEGENDARY_LIBSTDCXX_HACK
+#	endif
 #endif
 
 // Autotools config.h
