--- extra-1.5.3/extra.cabal~	2017-06-13 06:58:38.000000000 +0900

+++ extra-1.5.3/extra.cabal	2018-01-09 20:24:52.221337034 +0900

@@ -74,7 +74,7 @@

     if !os(windows)

         build-depends: unix

     hs-source-dirs: test

-    ghc-options: -main-is Test -threaded "-with-rtsopts=-N4 -K1K"

+    ghc-options: -main-is Test -threaded "-with-rtsopts=-K1K"

     main-is:        Test.hs

     other-modules:

         TestCustom