From 81548bf7da236e213733f1a151a4351ae80e6b93 Mon Sep 17 00:00:00 2001
From: Robin Gloster <mail@glob.in>
Date: Tue, 29 Oct 2019 23:21:22 +0100
Subject: [PATCH] olm: *Flags are lists

---
 pkgs/development/libraries/olm/default.nix | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/pkgs/development/libraries/olm/default.nix b/pkgs/development/libraries/olm/default.nix
index 224c01e2c50a..8fbdf28965bf 100644
--- a/pkgs/development/libraries/olm/default.nix
+++ b/pkgs/development/libraries/olm/default.nix
@@ -15,9 +15,11 @@ stdenv.mkDerivation rec {
   # requires optimisation but memory operations are compiled with -O0
   hardeningDisable = ["fortify"];
 
-  makeFlags = if stdenv.cc.isClang then [ "CC=cc" ] else null;
+  makeFlags = stdenv.lib.optional stdenv.cc.isClang "CC=cc";
 
-  installFlags = "PREFIX=$(out)";
+  installFlags = [
+    "PREFIX=${placeholder ''out''}"
+  ];
 
   meta = {
     description = "Implements double cryptographic ratchet and Megolm ratchet";