diff --git a/pkgs/development/compilers/llvm/3.9/llvm.nix b/pkgs/development/compilers/llvm/3.9/llvm.nix
index 96efc97323c6..964b6232fb54 100644
--- a/pkgs/development/compilers/llvm/3.9/llvm.nix
+++ b/pkgs/development/compilers/llvm/3.9/llvm.nix
@@ -53,8 +53,8 @@ in stdenv.mkDerivation rec {
   buildInputs = [
     groff
     libxml2
-    libffi ]
-    ++ stdenv.lib.optionals stdenv.isDarwin [ libcxxabi ];
+    libffi
+  ] ++ stdenv.lib.optionals stdenv.isDarwin [ libcxxabi ];
 
   propagatedBuildInputs = [ ncurses zlib ];