From 21a83ed49b4186f7f4bb0bd39ef17fdced4e786e Mon Sep 17 00:00:00 2001
From: Peter Simons <simons@cryp.to>
Date: Thu, 10 Jul 2014 15:13:03 +0200
Subject: [PATCH] darcs: build with ghc 7.6.3 to avoid errors with 7.8.x

---
 pkgs/top-level/all-packages.nix | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 819eaad27b1..cb7ac23cf3b 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -8270,10 +8270,11 @@ let
 
   d4x = callPackage ../applications/misc/d4x { };
 
-  darcs = haskellPackages.darcs.override {
+  darcs = haskellPackages_ghc763.darcs.override {
     # A variant of the Darcs derivation that containts only the executable and
-    # thus has no dependencies on other Haskell packages.
-    cabal = haskellPackages.cabal.override {
+    # thus has no dependencies on other Haskell packages. We have to use the older
+    # GHC 7.6.3 package set because darcs won't compile with 7.8.x.
+    cabal = haskellPackages_ghc763.cabal.override {
       extension = self : super : {
         isLibrary = false;
         configureFlags = "-f-library " + super.configureFlags or "";