From 7139d2c8815121bb4d028d8749985f3105d1e272 Mon Sep 17 00:00:00 2001
From: Robin Gloster <mail@glob.in>
Date: Tue, 29 Oct 2019 23:21:22 +0100
Subject: [PATCH] vxl: *Flags are lists

---
 pkgs/development/libraries/vxl/default.nix | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/pkgs/development/libraries/vxl/default.nix b/pkgs/development/libraries/vxl/default.nix
index 9651e9a5f80c..17d11d4fb749 100644
--- a/pkgs/development/libraries/vxl/default.nix
+++ b/pkgs/development/libraries/vxl/default.nix
@@ -11,14 +11,17 @@ stdenv.mkDerivation {
 
   buildInputs = [ cmake unzip libtiff expat zlib libpng libjpeg ];
 
-  # BUILD_OUL wants old linux headers for videodev.h, not available
-  # in stdenv linux headers
-  # BUILD_BRL fails to find open()
-  cmakeFlags = "-DBUILD_OUL=OFF -DBUILD_BRL=OFF -DBUILD_CONTRIB=OFF "
-    + (if stdenv.hostPlatform.system == "x86_64-linux" then
-      "-DCMAKE_CXX_FLAGS=-fPIC -DCMAKE_C_FLAGS=-fPIC"
-    else
-      "");
+  cmakeFlags = [
+    # BUILD_OUL wants old linux headers for videodev.h, not available
+    # in stdenv linux headers
+    "-DBUILD_OUL=OFF"
+    # BUILD_BRL fails to find open()
+    "-DBUILD_BRL=OFF"
+    "-DBUILD_CONTRIB=OFF"
+  ] ++ stdenv.lib.optionals (stdenv.hostPlatform.system == "x86_64-linux") [
+    "-DCMAKE_CXX_FLAGS=-fPIC"
+    "-DCMAKE_C_FLAGS=-fPIC"
+  ];
 
   enableParallelBuilding = true;