diff --git a/pkgs/applications/office/libreoffice/default.nix b/pkgs/applications/office/libreoffice/default.nix
index 70b439a5f77..c01048cdb3e 100644
--- a/pkgs/applications/office/libreoffice/default.nix
+++ b/pkgs/applications/office/libreoffice/default.nix
@@ -57,7 +57,9 @@ in (stdenv.mkDerivation rec {
 
   # For some reason librdf_redland sometimes refers to rasqal.h instead
   # of rasqal/rasqal.h
-  NIX_CFLAGS_COMPILE = builtins.toString ([ "-I${librdf_rasqal}/include/rasqal" ] ++ lib.optional stdenv.isx86_64 "-mno-fma");
+  NIX_CFLAGS_COMPILE = [
+    "-I${librdf_rasqal}/include/rasqal"
+  ] ++ lib.optional stdenv.isx86_64 "-mno-fma";
 
   patches = [
     ./xdg-open-brief.patch