Index: libcfa/src/concurrency/thread.hfa
===================================================================
--- libcfa/src/concurrency/thread.hfa	(revision e23542987c42024e758269c7930ff52bdaf97f78)
+++ libcfa/src/concurrency/thread.hfa	(revision 342be435469470dee71cab92b46cf14f8fee7f3a)
@@ -22,12 +22,24 @@
 #include "kernel.hfa"
 #include "monitor.hfa"
+#include "exception.hfa"
 
 //-----------------------------------------------------------------------------
 // thread trait
 trait is_thread(dtype T) {
-      void ^?{}(T& mutex this);
-      void main(T& this);
-      $thread* get_thread(T& this);
+	void ^?{}(T& mutex this);
+	void main(T& this);
+	$thread* get_thread(T& this);
 };
+
+FORALL_DATA_EXCEPTION(ThreadCancelled, (dtype thread_t), (thread_t)) (
+	thread_t * the_thread;
+	exception_t * the_exception;
+);
+
+forall(dtype T)
+void copy(ThreadCancelled(T) * dst, ThreadCancelled(T) * src);
+
+forall(dtype T)
+const char * msg(ThreadCancelled(T) *);
 
 // define that satisfies the trait without using the thread keyword
@@ -65,4 +77,12 @@
 static inline void ?{}($thread & this, const char * const name, struct cluster & cl )                   { this{ name, cl, 0p, 65000 }; }
 static inline void ?{}($thread & this, const char * const name, struct cluster & cl, size_t stackSize ) { this{ name, cl, 0p, stackSize }; }
+
+struct thread_dtor_guard_t {
+	monitor_dtor_guard_t mg;
+};
+
+forall( dtype T | is_thread(T) | IS_EXCEPTION(ThreadCancelled, (T)) )
+void ?{}( thread_dtor_guard_t & this, T & thrd, void(*)(ThreadCancelled(T) &) );
+void ^?{}( thread_dtor_guard_t & this );
 
 //-----------------------------------------------------------------------------
@@ -108,5 +128,5 @@
 //----------
 // join
-forall( dtype T | is_thread(T) )
+forall( dtype T | is_thread(T) | IS_RESUMPTION_EXCEPTION(ThreadCancelled, (T)) )
 T & join( T & this );