Warn, not error, on duplicate modules (fixes #5407)

Author: snoyberg

src/Stack/Ghci.hs

@@ -825,7 +825,9 @@ checkForDuplicateModules pkgs = do
         borderedWarning $ do
             prettyError $ "Multiple files use the same module name:" <>
               line <> bulletedList (map prettyDuplicate duplicates)
-        throwM LoadingDuplicateModules
+        -- MSS 2020-10-13 Disabling, may remove entirely in the future
+        -- See: https://github.com/commercialhaskell/stack/issues/5407#issuecomment-707339928
+        -- throwM LoadingDuplicateModules
   where
     duplicates :: [(ModuleName, Map (Path Abs File) (Set (PackageName, NamedComponent)))]
     duplicates =