diff options
Diffstat (limited to 'libraries/base/Control/Concurrent')
| -rw-r--r-- | libraries/base/Control/Concurrent/MVar.hs | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/libraries/base/Control/Concurrent/MVar.hs b/libraries/base/Control/Concurrent/MVar.hs index 45c05fdc9b..5ffac11077 100644 --- a/libraries/base/Control/Concurrent/MVar.hs +++ b/libraries/base/Control/Concurrent/MVar.hs @@ -270,5 +270,8 @@ addMVarFinalizer = GHC.MVar.addMVarFinalizer -- -- @since 4.6.0.0 mkWeakMVar :: MVar a -> IO () -> IO (Weak (MVar a)) -mkWeakMVar m@(MVar m#) f = IO $ \s -> - case mkWeak# m# m f s of (# s1, w #) -> (# s1, Weak w #) +mkWeakMVar m@(MVar m#) (IO f) = IO $ \s -> + case mkWeak# m# m finalizer s of (# s1, w #) -> (# s1, Weak w #) + where + finalizer :: State# RealWorld -> State# RealWorld + finalizer s' = case f s' of (# s'', () #) -> s'' |