diff --git a/pkgs/development/libraries/libc++/default.nix b/pkgs/development/libraries/libc++/default.nix
index 6dc49f4684e..9f6f1ecdeb5 100644
--- a/pkgs/development/libraries/libc++/default.nix
+++ b/pkgs/development/libraries/libc++/default.nix
@@ -1,9 +1,8 @@
 { stdenv, fetchurl, cmake, libcxxabi }:
 
-let
-  version = "3.4.2";
+let version = "3.4.2"; in
 
-in stdenv.mkDerivation rec {
+stdenv.mkDerivation rec {
   name = "libc++-${version}";
 
   src = fetchurl {
@@ -21,6 +20,9 @@ in stdenv.mkDerivation rec {
 
   passthru.abi = libcxxabi;
 
+  # Remove a Makefile that causes many retained dependencies.
+  postInstall = "rm $out/include/c++/v1/Makefile";
+
   meta = {
     homepage = http://libcxx.llvm.org/;
     description = "A new implementation of the C++ standard library, targeting C++11";