From f6514239ee9b0739a6e884ba28e9302c0102f8c0 Mon Sep 17 00:00:00 2001
From: Frederik Rietdijk <fridh@fridh.nl>
Date: Thu, 31 Dec 2020 09:30:44 +0100
Subject: [PATCH] hidapi: fix cross build

---
 pkgs/development/libraries/hidapi/default.nix | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/pkgs/development/libraries/hidapi/default.nix b/pkgs/development/libraries/hidapi/default.nix
index c42a3528223..80f7aa150c4 100644
--- a/pkgs/development/libraries/hidapi/default.nix
+++ b/pkgs/development/libraries/hidapi/default.nix
@@ -1,5 +1,7 @@
 { stdenv, fetchFromGitHub, autoreconfHook, pkgconfig, udev, libusb1
-, darwin }:
+, darwin
+, gnum4
+}:
 
 stdenv.mkDerivation rec {
   pname = "hidapi";
@@ -12,7 +14,13 @@ stdenv.mkDerivation rec {
     sha256 = "1nr4z4b10vpbh3ss525r7spz4i43zim2ba5qzfl15dgdxshxxivb";
   };
 
-  nativeBuildInputs = [ autoreconfHook pkgconfig ];
+  nativeBuildInputs = [
+    autoreconfHook
+    pkgconfig
+  ] ++ stdenv.lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
+    # Could be added always, but added conditionally here to avoid large rebuild
+    gnum4
+  ];
 
   buildInputs = [ ]
     ++ stdenv.lib.optionals stdenv.isLinux [ libusb1 udev ];