id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
4123	Control.Concurrent.MVar doesn't need to depend on the Prelude	tibbe		"`Control.Concurrent.MVar` currently depends on the `Prelude`, causing an import cycle in the new I/O manager. This patch replaces the dependency on the `Prelude` with modules in the `GHC` hierarchy, breaking the cycle. 
"	bug	closed	high	7.0.1	libraries/base	6.13	fixed			Unknown/Multiple	Unknown/Multiple	Building GHC failed