From 7dc28c88bc4d9cb5ad06f4d7d8b33a5eb0cae079 Mon Sep 17 00:00:00 2001
From: Thomas <twatson52@icloud.com>
Date: Tue, 17 Aug 2021 19:00:13 -0500
Subject: [PATCH] opencv: fix OpenCL linkage

---
 pkgs/development/libraries/opencv/4.x.nix | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pkgs/development/libraries/opencv/4.x.nix b/pkgs/development/libraries/opencv/4.x.nix
index a33eff4faa53..cfc654717f52 100644
--- a/pkgs/development/libraries/opencv/4.x.nix
+++ b/pkgs/development/libraries/opencv/4.x.nix
@@ -12,6 +12,7 @@
 , gflags
 , protobuf
 , config
+, ocl-icd
 
 , enableJPEG ? true
 , libjpeg
@@ -305,6 +306,8 @@ stdenv.mkDerivation {
   ] ++ lib.optionals stdenv.isDarwin [
     "-DWITH_OPENCL=OFF"
     "-DWITH_LAPACK=OFF"
+  ] ++ lib.optionals (!stdenv.isDarwin) [
+    "-DOPENCL_LIBRARY=${ocl-icd}/lib/libOpenCL.so"
   ] ++ lib.optionals enablePython [
     "-DOPENCV_SKIP_PYTHON_LOADER=ON"
   ];