id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
4813	Program hangs without -threaded option	mitar	simonmar	"Attached program hangs without `-threaded` option very often (but not always). With `-threaded` it works as it should (exits almost immediately with an exception). As program does not use any FFI and almost none IO I think this is a bug.

I wasn't able to remove use of [http://hackage.haskell.org/package/Etage Etage] but I did simplified it much.

I tried to pin down the problem with debug messages in the library and it seems that although the `SampleVar` (I use to mark that thread has finished) is filled, main thread is still blocked on reading it. I have tested this by printing things before and after writing and reading. So print after writing is seen but reading is still waiting.

I am using 7.1.20101124. Tested both on Mac OS X and Linux amd64."	bug	closed	high	7.0.2	Compiler	7.1	fixed		mmitar@…	Unknown/Multiple	Unknown/Multiple	None/Unknown