From 33a6220244cf59a26d2cfb05f8ad7fcb5c005c3b Mon Sep 17 00:00:00 2001
From: Sergei Trofimovich <slyich@gmail.com>
Date: Sat, 18 Sep 2021 19:59:01 +0100
Subject: [PATCH] osl: fix build by overriding llvm-as path

Closes: https://github.com/NixOS/nixpkgs/issues/138373
---
 pkgs/development/compilers/osl/default.nix | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/compilers/osl/default.nix b/pkgs/development/compilers/osl/default.nix
index eeaba75c0de4..736a9d3c34c6 100644
--- a/pkgs/development/compilers/osl/default.nix
+++ b/pkgs/development/compilers/osl/default.nix
@@ -17,7 +17,15 @@ in clangStdenv.mkDerivation rec {
     sha256 = "1dwf10f2fpxc55pymwkapql20nc462mq61hv21c527994c2qp1ll";
   };
 
-  cmakeFlags = [ "-DUSE_BOOST_WAVE=ON" "-DENABLERTTI=ON" ];
+  cmakeFlags = [
+    "-DUSE_BOOST_WAVE=ON"
+    "-DENABLERTTI=ON"
+
+    # Build system implies llvm-config and llvm-as are in the same directory.
+    # Override defaults.
+    "-DLLVM_DIRECTORY=${llvm}"
+    "-DLLVM_CONFIG=${llvm.dev}/bin/llvm-config"
+  ];
 
   preConfigure = "patchShebangs src/liboslexec/serialize-bc.bash ";