  import GHC.Conc.Sync
  
 -#if !defined(mingw32_HOST_OS)
-+#if !defined(mingw32_HOST_OS) && !defined(ghcjs_HOST_OS)
++#if !defined(mingw32_HOST_OS) || defined(ghcjs_HOST_OS)
  import GHC.Conc.Signal
  #endif
 diff -Nru upstream/pkg/base/GHC/Event/Manager.hs boot/pkg/base/GHC/Event/Manager.hs

 
+#endif
diff -Nru upstream/pkg/base/GHC/Conc.hs boot/pkg/base/GHC/Conc.hs
--- upstream/pkg/base/GHC/Conc.hs	2018-01-23 23:17:56.000000000 +0100
+++ boot/pkg/base/GHC/Conc.hs	2018-04-20 05:07:18.566023075 +0200
@@ -95,14 +95,14 @@
         , asyncWriteBA
 #endif
 
-#if !defined(mingw32_HOST_OS)
+#if !defined(mingw32_HOST_OS) && !defined(ghcjs_HOST_OS)
         , Signal, HandlerFun, setHandler, runHandlers
 #endif
 

diff -Nru upstream/pkg/base/base.cabal boot/pkg/base/base.cabal
--- upstream/pkg/base/base.cabal	2018-04-26 09:55:16.000000000 +0000
+++ boot/pkg/base/base.cabal	2018-04-26 09:55:16.675026534 +0000
@@ -1,4 +1,4 @@
-cabal-version:  2.1
+cabal-version:  2.2
 name:           base
 version:        4.11.1.0
 -- NOTE: Don't forget to update ./changelog.md
@@ -51,7 +51,7 @@
 Flag integer-gmp
