diff --git a/Xfuncproto.h.in b/Xfuncproto.h.in
index afdd95b..96a585c 100644
--- a/Xfuncproto.h.in
+++ b/Xfuncproto.h.in
@@ -117,4 +117,10 @@ in this Software without prior written authorization from The Open Group.
 # define _X_DEPRECATED
 #endif
 
+#if defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 205)
+# define _X_NORETURN __attribute((noreturn))
+#else
+# define _X_NORETURN
+#endif /* GNUC  */
+
 #endif /* _XFUNCPROTO_H_ */