prevent crash for WinIO in GHC 9+

silently.cabal

@@ -63,50 +63,21 @@ Library
     ghc-options:
       -Wcompat
 
--- This tests the platform specific implementation.
---
--- NOTE: Cabal 1.10 can not deal with conditional (== if-else) options.  This
--- is why we depend on silently to test the platform specific implementation.
---
--- As a consequence we can not use Hspec for testing, as this would result in
--- depending on two different versions of silently at the same time!
-test-suite spec-specific
-  type:
-      exitcode-stdio-1.0
-  hs-source-dirs:
-      test
-  main-is:
-      Spec.hs
-  default-language:
-      Haskell98
-  ghc-options:
-      -Wall -threaded
-  build-depends:
-      base
-    , silently
-    , directory
-    , nanospec
-    , temporary
-
 -- This tests the generic implementation, that should work on all platforms.
 test-suite spec-generic
   type:
       exitcode-stdio-1.0
   hs-source-dirs:
-      src
-    , test
+      test
   main-is:
       Spec.hs
   default-language:
       Haskell98
   ghc-options:
-      -Wall -threaded
-  other-modules:
-      System.IO.Silently
-
+      -Wall -threaded -rtsopts
   build-depends:
       base
-    , deepseq
+    , silently
     , directory
     , nanospec
     , temporary

src/System/IO/Silently.hs

@@ -27,6 +27,10 @@ import System.IO
   , openFile, openTempFile, stdout
   )
 
+#if defined(WINDOWS) && __GLASGOW_HASKELL__ >= 900
+import GHC.IO.SubSystem ((<!>))
+#endif
+
 mNullDevice :: Maybe FilePath
 #ifdef WINDOWS
 mNullDevice = Just "\\\\.\\NUL"
@@ -110,7 +114,15 @@ hCapture handles action = withTempFile "capture" prepareAndRun
         go (h:hs) = goBracket go tmpHandle h hs
 
 goBracket :: ([Handle] -> IO a) -> Handle -> Handle -> [Handle] -> IO a
-goBracket go tmpHandle h hs = do
+#if defined(WINDOWS) && __GLASGOW_HASKELL__ >= 900
+goBracket = goBracketPosix <!> giveUp
+  where giveUp go _ _ _ = go []
+#else
+goBracket = goBracketPosix
+#endif
+
+goBracketPosix :: ([Handle] -> IO a) -> Handle -> Handle -> [Handle] -> IO a
+goBracketPosix go tmpHandle h hs = do
   buffering <- hGetBuffering h
   let redirect = do
         old <- hDuplicate h