diff --git a/ChangeLog b/ChangeLog
index 0dde209f..f857c495 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,8 @@
 	parameter.
 	* src/userdel.c: Last audit_logger parameter is a
 	shadow_audit_result, use SHADOW_AUDIT_FAILURE instead of 0.
+	* lib/selinux.c: vasprintf requires _GNU_SOURCE to be defined
+	before including stdio.h.
 
 2011-11-19  Nicolas François  <nicolas.francois@centraliens.net>
 
diff --git a/lib/selinux.c b/lib/selinux.c
index e8b0726f..a6ba99c7 100644
--- a/lib/selinux.c
+++ b/lib/selinux.c
@@ -34,6 +34,7 @@
 
 #include "defines.h"
 
+#define _GNU_SOURCE
 #include <stdio.h>
 #include <stdarg.h>
 #include <selinux/selinux.h>