diff --git a/src/tint2conf/main.c b/src/tint2conf/main.c
index 356ef9d..e9767ba 100644
--- a/src/tint2conf/main.c
+++ b/src/tint2conf/main.c
@@ -17,6 +17,7 @@
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 **************************************************************************/
 
+#include <stdlib.h>
 #include <stdio.h>
 #include <locale.h>
 #include <gtk/gtk.h>