diff --git a/pkgs/development/libraries/libunistring/default.nix b/pkgs/development/libraries/libunistring/default.nix
index 02054f33ffd..dfd5593cf71 100644
--- a/pkgs/development/libraries/libunistring/default.nix
+++ b/pkgs/development/libraries/libunistring/default.nix
@@ -8,7 +8,7 @@ stdenv.mkDerivation rec {
     sha256 = "02qrsncjn7r350p1wgggkg14gbw2r4g4a7awvrggfriqs6nl5qf5";
   };
 
-  buildInputs =
+  propagatedBuildInputs =
     stdenv.lib.optional (stdenv.system == "i686-cygwin"
                          || stdenv.system == "i686-darwin")
                         libiconv;