Fix build with GHC 9

Author: pepeiborra

ghcide/src/Development/IDE/Core/Compile.hs

@@ -106,9 +106,9 @@ import           Data.Map                          (Map)
 import           Data.Tuple.Extra                  (dupe)
 import           Data.Unique                       as Unique
 import           Development.IDE.Core.Tracing      (withTrace)
+import           Development.IDE.GHC.Compat.Util   (emptyUDFM, plusUDFM)
 import qualified Language.LSP.Server               as LSP
 import qualified Language.LSP.Types                as LSP
-import           UniqDFM                           (emptyUDFM, plusUDFM)
 import           Unsafe.Coerce
 
 -- | Given a string buffer, return the string (after preprocessing) and the 'ParsedModule'.

ghcide/src/Development/IDE/GHC/Compat/Util.hs

@@ -59,6 +59,9 @@ module Development.IDE.GHC.Compat.Util (
     Unique,
     mkUnique,
     newTagUnique,
+    -- * UniqDFM
+    emptyUDFM,
+    plusUDFM,
     -- * String Buffer
     StringBuffer(..),
     hGetStringBuffer,
@@ -76,6 +79,7 @@ import           GHC.Data.Maybe
 import           GHC.Data.Pair
 import           GHC.Data.StringBuffer
 import           GHC.Types.Unique
+import           GHC.Types.Unique.DFM
 import           GHC.Utils.Fingerprint
 import           GHC.Utils.Misc
 import           GHC.Utils.Outputable    (pprHsString)
@@ -94,6 +98,7 @@ import           Pair
 import           Outputable              (pprHsString)
 import           Panic                   hiding (try)
 import           StringBuffer
+import           UniqDFM
 import           Unique
 import           Util
 #endif