[mutter] build: Use non-deprecated feature test macros

[Florian Müllner <fmuellner src gnome org>]

commit b159d6a5e17219557574defb6c3788d9b0c39757
Author: Florian Müllner <fmuellner gnome org>
Date:   Wed Mar 5 23:06:44 2014 +0100

    build: Use non-deprecated feature test macros
    
    _SVID_SOURCE has been deprecated in newer versions of glibc breaking
    -WError; the recommended replacement of _DEFAULT_SOURCE is fairly
    new, so switch to _XOPEN_SOURCE instead.

 src/core/keybindings.c  |    2 +-
 src/core/main.c         |    2 +-
 src/core/window-props.c |    2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/src/core/keybindings.c b/src/core/keybindings.c
index e97c0f2..f2c6631 100644
--- a/src/core/keybindings.c
+++ b/src/core/keybindings.c
@@ -28,7 +28,7 @@
  */
 
 #define _GNU_SOURCE
-#define _SVID_SOURCE /* for putenv() */
+#define _XOPEN_SOURCE /* for putenv() */
 
 #include <config.h>
 #include "keybindings-private.h"
diff --git a/src/core/main.c b/src/core/main.c
index b2eb4cd..3f5f3c5 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -42,7 +42,7 @@
  */
 
 #define _GNU_SOURCE
-#define _SVID_SOURCE /* for putenv() and some signal-related functions */
+#define _XOPEN_SOURCE /* for putenv() and some signal-related functions */
 
 #include <config.h>
 #include <meta/main.h>
diff --git a/src/core/window-props.c b/src/core/window-props.c
index b7799db..81dce84 100644
--- a/src/core/window-props.c
+++ b/src/core/window-props.c
@@ -35,7 +35,7 @@
  */
 
 #define _GNU_SOURCE
-#define _SVID_SOURCE /* for gethostname() */
+#define _XOPEN_SOURCE 500 /* for gethostname() */
 
 #include <config.h>
 #include "window-props.h"