diff --git a/core/include/queue.h b/core/include/queue.h
index d7a122e50..ae377409d 100644
--- a/core/include/queue.h
+++ b/core/include/queue.h
@@ -23,6 +23,7 @@ void queue_add_head(queue_node_t* root, queue_node_t* new_obj);
 queue_node_t *queue_remove_head(queue_node_t* root);
 void queue_priority_add(queue_node_t* root, queue_node_t* new_obj);
 void queue_priority_add_generic(queue_node_t* root, queue_node_t* new_obj, int(*cmp)(queue_node_t*,queue_node_t*)) ;
+void queue_remove(queue_node_t* root, queue_node_t *node);
 
 /** @} */
 #endif // __QUEUE_H
diff --git a/core/include/sched.h b/core/include/sched.h
index bce386431..9f9712249 100644
--- a/core/include/sched.h
+++ b/core/include/sched.h
@@ -27,13 +27,13 @@ void sched_run();
 void sched_set_status(tcb_t *process, unsigned int status);
 void sched_switch(uint16_t current_prio, uint16_t other_prio, int in_isr);
 
-volatile unsigned int sched_context_switch_request;
+extern volatile unsigned int sched_context_switch_request;
 
-volatile tcb_t *sched_threads[MAXTHREADS];
-volatile tcb_t *active_thread;
+extern volatile tcb_t *sched_threads[MAXTHREADS];
+extern volatile tcb_t *active_thread;
 
 extern volatile int num_tasks;
-volatile int thread_pid;
+extern volatile int thread_pid;
 
 //#define SCHEDSTATISTICS
 #if SCHEDSTATISTICS
diff --git a/core/sched.c b/core/sched.c
index 9b33d386d..51fdaef62 100644
--- a/core/sched.c
+++ b/core/sched.c
@@ -25,6 +25,13 @@
 
 volatile int num_tasks = 0;
 
+volatile unsigned int sched_context_switch_request;
+
+volatile tcb_t *sched_threads[MAXTHREADS];
+volatile tcb_t *active_thread;
+
+volatile int thread_pid;
+
 clist_node_t *runqueues[SCHED_PRIO_LEVELS];
 static uint32_t runqueue_bitcache = 0;