Index: kernel/generic/include/ipc/ipc.h
===================================================================
--- kernel/generic/include/ipc/ipc.h	(revision b76a22177c4c3a1dbff86603b43c86fa730488e2)
+++ kernel/generic/include/ipc/ipc.h	(revision d79dcdb243234a393790bfe6920e372ef1b3ff49)
@@ -273,6 +273,6 @@
 extern void task_print_list(void);
 extern int ipc_forward(call_t *call, phone_t *newphone, answerbox_t *oldbox);
-void ipc_cleanup(void);
-int ipc_phone_hangup(phone_t *phone);
+extern void ipc_cleanup(void);
+extern int ipc_phone_hangup(phone_t *phone);
 extern void ipc_backsend_err(phone_t *phone, call_t *call, unative_t err);
 extern void ipc_print_task(task_id_t taskid);