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diff --git a/compiler/main/GHC.hs b/compiler/main/GHC.hs
index 44ec3ff..0ecc09b 100644 (file)
--- a/compiler/main/GHC.hs
+++ b/compiler/main/GHC.hs
@@ -933,6 +933,10 @@ getPackageModuleInfo :: HscEnv -> Module -> IO (Maybe ModuleInfo)
 #ifdef GHCI
 getPackageModuleInfo hsc_env mdl = do
   mb_avails <- hscGetModuleExports hsc_env mdl
 #ifdef GHCI
 getPackageModuleInfo hsc_env mdl = do
   mb_avails <- hscGetModuleExports hsc_env mdl

+     -- This is the only use of hscGetModuleExports.  Perhaps we could use
+     -- hscRnImportDecls instead, but that does a lot more than we need
+     -- (building instance environment, checking family instance consistency
+     -- etc.).

   case mb_avails of
     Nothing -> return Nothing
     Just avails -> do
   case mb_avails of
     Nothing -> return Nothing
     Just avails -> do