Here are some examples showing the problem.

Example1:
-------------

~~~~~~~~~~~~~~~~~~~~
class FOO

create

	make

feature

	make
		local
			l_thread: MY_THREAD
		do
			print ("Thread start%N")
			create l_thread.make
			l_thread.launch
			l_thread.join
			print ("Thread done%N")
		end

end
~~~~~~~~~~~~~~~~~~~~
class MY_THREAD

inherit

	THREAD
		rename
			terminated as thread_terminated
		end

create

	make

feature

	execute
		do
			print ("Execute thread (start)%N")
			(create {EXECUTION_ENVIRONMENT}).sleep (5000000000)
			print ("Execute thread (done)%N")
		end

end
~~~~~~~~~~~~~~~~~~~~

Output:
~~~~~~~~~~~~~~~~~~~~
Thread start
Execute thread (start)
Execute thread (done)
~~~~~~~~~~~~~~~~~~~~

The program never terminates.

Example2:
-------------

~~~~~~~~~~~~~~~~~~~~
class FOO

create

	make

feature

	make
		local
			l_thread: MY_THREAD
		do
			print ("Thread start%N")
			create l_thread.make
			l_thread.launch
			l_thread.join
			print ("Thread done%N")
			print ("%N")
		end

end
~~~~~~~~~~~~~~~~~~~~
class MY_THREAD

inherit

	THREAD
		rename
			terminated as thread_terminated
		end

create

	make

feature

	terminated: INTEGER

	execute
		do
			print ("Execute thread (start)%N")
			terminated := 0xFFFFFFFF
			(create {EXECUTION_ENVIRONMENT}).sleep (5000000000)
			print ("Execute thread (done)%N")
		end

end
~~~~~~~~~~~~~~~~~~~~

Output:
~~~~~~~~~~~~~~~~~~~~
Thread start
Execute thread (start)
Thread done
~~~~~~~~~~~~~~~~~~~~

The main thread stopped waiting, even though the thread was not finished.

Example3:
------------

~~~~~~~~~~~~~~~~~~~~
class FOO

create

	make

feature

	make
		local
			l_thread: MY_THREAD
		do
			print ("Thread start%N")
			create l_thread.make
			l_thread.launch
			l_thread.join
			print ("Thread done%N")
			print (l_thread.terminated)
			print ("%N")
		end

end
~~~~~~~~~~~~~~~~~~~~
class MY_THREAD

inherit

	THREAD
		rename
			terminated as thread_terminated
		end

create

	make

feature

	terminated: INTEGER

	execute
		do
			print ("Execute thread (start)%N")
			(create {EXECUTION_ENVIRONMENT}).sleep (5000000000)
			print ("Execute thread (done)%N")
		end

end
~~~~~~~~~~~~~~~~~~~~

Output:
~~~~~~~~~~~~~~~~~~~~
Thread start
Execute thread (start)
Execute thread (done)
Thread done
1
~~~~~~~~~~~~~~~~~~~~

Here the integer attribute `terminated' has been overwritten.
I don't want to imagine what would happen to the memory management if my attribute was a reference.

Tomorrow I will try to provide a bug fix using a setter (to be passed to {THREAD}.create_thread_with_attr, kept in the thread context on the C side, and then called in `eif_thr_exit') and a getter (to be passed to {THREAD}.thread_wait and {THREAD}.thread_wait_with_timeout).

--
Eric Bezault