takeMVar/putMVar were missing some write barriers when modifying a TSO
This relates to the recent introduction of clean/dirty TSOs, and the consqeuent write barriers required. We were missing some write barriers in the takeMVar/putMVar family of primops, when performing the take/put directly on another TSO. Fixes #705, and probably some test failures.
Showing with 10 additions and 6 deletions