From a7203c54e8766d91ef0ec4b82be4ec36d686e114 Mon Sep 17 00:00:00 2001
From: Peter Simons <simons@cryp.to>
Date: Thu, 29 Mar 2018 11:06:55 +0200
Subject: [PATCH] haskell-arrows: apply patch to fix build with ghc 8.4.1

---
 .../development/haskell-modules/configuration-ghc-8.4.x.nix | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/pkgs/development/haskell-modules/configuration-ghc-8.4.x.nix b/pkgs/development/haskell-modules/configuration-ghc-8.4.x.nix
index 877636fe56c..ec9215175f8 100644
--- a/pkgs/development/haskell-modules/configuration-ghc-8.4.x.nix
+++ b/pkgs/development/haskell-modules/configuration-ghc-8.4.x.nix
@@ -637,4 +637,10 @@ self: super: {
   # https://github.com/xmonad/xmonad-contrib/issues/235
   xmonad-contrib = doJailbreak (appendPatch super.xmonad-contrib ./patches/xmonad-contrib-ghc-8.4.1-fix.patch);
 
+  # Contributed by Bertram Felgenhauer <int-e@gmx.de>.
+  arrows = appendPatch super.arrows (pkgs.fetchpatch {
+    url = https://raw.githubusercontent.com/lambdabot/lambdabot/ghc-8.4.1/patches/arrows-0.4.4.1.patch;
+    sha256 = "0j859vclcfnz8n2mw466mv00kjsa9gdbrppjc1m3b68jbypdmfvr";
+  });
+
 }