gnu: luit: Accomodate stricter warnings of gcc-4.8.

* gnu/packages/patches/luit-posix.patch: New file.
* gnu-system.am (dist_patch_DATA): Register patch.
* gnu/packages/xorg.scm (luit): Apply patch.

gnu-system.am

@@ -254,6 +254,7 @@ dist_patch_DATA =						\
   gnu/packages/patches/libtheora-config-guess.patch		\
   gnu/packages/patches/libtool-skip-tests.patch			\
   gnu/packages/patches/libtool-skip-tests-for-mips.patch	\
+  gnu/packages/patches/luit-posix.patch				\
   gnu/packages/patches/m4-gets-undeclared.patch			\
   gnu/packages/patches/m4-readlink-EINVAL.patch			\
   gnu/packages/patches/make-impure-dirs.patch			\

gnu/packages/patches/luit-posix.patch

@@ -0,0 +1,15 @@
+See https://bugs.freedesktop.org/show_bug.cgi?id=47792;
+should become obsolete with the next release.
+
+diff -u luit-1.1.1.orig/sys.c luit-1.1.1/sys.c
+--- luit-1.1.1.orig/sys.c	2012-03-23 05:23:07.000000000 +0100
++++ luit-1.1.1/sys.c	2013-11-27 22:45:53.000000000 +0100
+@@ -20,6 +20,8 @@
+ THE SOFTWARE.
+ */
+ 
++#define _XOPEN_SOURCE 600
++
+ #ifdef HAVE_CONFIG_H
+ # include "config.h"
+ #endif

gnu/packages/xorg.scm

@@ -1406,7 +1406,10 @@ tracking.")
                ".tar.bz2"))
         (sha256
           (base32
-            "0dn694mk56x6hdk6y9ylx4f128h5jcin278gnw2gb807rf3ygc1h"))))
+            "0dn694mk56x6hdk6y9ylx4f128h5jcin278gnw2gb807rf3ygc1h"))
+        ;; See https://bugs.freedesktop.org/show_bug.cgi?id=47792;
+        ;; should become obsolete with the next release.
+        (patches (list (search-patch "luit-posix.patch")))))
     (build-system gnu-build-system)
     (inputs
       `(("libfontenc" ,libfontenc)