From d1c9beebdbf22aa04419a1fe412c43160552aef7 Mon Sep 17 00:00:00 2001
From: Franz Pletz <fpletz@fnordicwalking.de>
Date: Mon, 11 Dec 2017 09:42:44 +0100
Subject: [PATCH] xmr-stak: fix evaluation with nix 1.11

---
 pkgs/applications/misc/xmr-stak/default.nix | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pkgs/applications/misc/xmr-stak/default.nix b/pkgs/applications/misc/xmr-stak/default.nix
index d12f649d5ee4..e5a419f6a8c1 100644
--- a/pkgs/applications/misc/xmr-stak/default.nix
+++ b/pkgs/applications/misc/xmr-stak/default.nix
@@ -1,6 +1,6 @@
 { stdenv, lib, fetchFromGitHub, cmake, libuv, libmicrohttpd, openssl
 , opencl-headers, ocl-icd, hwloc, cudatoolkit
-, devDonationLevel ? 0.0
+, devDonationLevel ? "0.0"
 , cudaSupport ? false  # doesn't work currently
 }:
 
@@ -26,7 +26,7 @@ stdenv.mkDerivation rec {
 
   postPatch = ''
     substituteInPlace xmrstak/donate-level.hpp \
-      --replace 'fDevDonationLevel = 2.0' 'fDevDonationLevel = ${toString devDonationLevel}'
+      --replace 'fDevDonationLevel = 2.0' 'fDevDonationLevel = ${devDonationLevel}'
   '';
 
   meta = with lib; {