Update T3279 to use mask rather than block

I'm not 100% sure that this is still testing what it's meant to be
testing, but the test still passes.

1 files changed, 14 insertions, 8 deletions

diff --git a/testsuite/tests/concurrent/should_run/T3279.hs b/testsuite/tests/concurrent/should_run/T3279.hs
index f479704310..46e9b03674 100644
--- a/testsuite/tests/concurrent/should_run/T3279.hs
+++ b/testsuite/tests/concurrent/should_run/T3279.hs
@@ -1,24 +1,30 @@
 -- test for #3279
 
+import Data.IORef
 import System.IO.Unsafe
 import GHC.Conc
 import Control.Exception
 
-f :: Int
-f = (1 +) . unsafePerformIO $ do
-        error "foo" `catch` \(SomeException e) -> do
-            myThreadId >>= flip throwTo e
-            -- point X
-            unblock $ return 1
-
 main :: IO ()
 main = do
+    restoreRef <- newIORef id
+
+    let f :: Int
+        f = (1 +) . unsafePerformIO $ do
+                error "foo" `catch` \(SomeException e) -> do
+                    myThreadId >>= flip throwTo e
+                    -- point X
+                    restore <- readIORef restoreRef
+                    restore $ return 1
+
     evaluate f `catch` \(SomeException e) -> return 0
     -- the evaluation of 'x' is now suspended at point X
-    tid <- block $ forkIO (evaluate f >> return ())
+    tid <- mask $ \restore -> do writeIORef restoreRef restore
+                                 forkIO (evaluate f >> return ())
     killThread tid
     -- now execute the 'unblock' above with a pending exception
     yield
+    writeIORef restoreRef id
     -- should print 1 + 1 = 2
     print f