Fix test bugs

* t8108 cannot run as a thread in the same process as other tests.
  It could perhaps run last.  But I'm not convinced we should bother.
* Fix deallocation/write race in FdReadBuf001

Author: hs-viktor

tests/FdReadBuf001.hs

@@ -2,7 +2,7 @@ module Main where
 
 import System.Posix
 import Control.Monad
-import Foreign
+import Foreign hiding (void)
 import Control.Concurrent
 import Data.Char
 import System.Exit
@@ -13,10 +13,10 @@ main = do
       block = 512
   (rd,wr) <- createPipe
   let bytes = take size (map (fromIntegral.ord) (cycle ['a'..'z']))
-  _ <- allocaBytes size $ \p -> do
-    pokeArray p bytes
-    forkIO $ do r <- fdWriteBuf wr p (fromIntegral size)
-                when (fromIntegral r /= size) $ error "fdWriteBuf failed"
+  void $ forkIO $ allocaBytes size $ \p -> do
+        pokeArray p bytes
+        r <- fdWriteBuf wr p (fromIntegral size)
+        when (fromIntegral r /= size) $ error "fdWriteBuf failed"
   allocaBytes block $ \p -> do
     let loop text = do
            r <- fdReadBuf rd p (fromIntegral block)

tests/Test.hs

@@ -38,7 +38,6 @@ main = defaultMain $ testGroup "All"
   , signals001
   , t1185
   , t3816
-  , t8108
   , user001
   , posix002
   , posix005
@@ -163,12 +162,6 @@ t3816 = testCase "T3816" $ do
   not . null <$> getAllGroupEntries
     @? "should be non-empty"
 
-t8108 :: TestTree
-t8108 = testCase "T8108" $ do
-  void $ forkIO $ forever $ getGroupEntryForID 0
-  void $ forkIO $ forever $ getGroupEntryForID 0
-  threadDelay 3000000
-
 user001 :: TestTree
 user001 = testCase "user001" $ do
   let force act = do