diff --git a/pkgs/stdenv/nix/default.nix b/pkgs/stdenv/nix/default.nix
index b16c51f7580b..78e5b84a841e 100644
--- a/pkgs/stdenv/nix/default.nix
+++ b/pkgs/stdenv/nix/default.nix
@@ -9,6 +9,7 @@ import ../generic rec {
       export NIX_IGNORE_LD_THROUGH_GCC=1
 
       if [ "$system" = "i686-darwin" -o "$system" = "powerpc-darwin" -o "$system" = "x86_64-darwin" ]; then
+        export NIX_ENFORCE_PURITY=
         export NIX_DONT_SET_RPATH=1
         export NIX_NO_SELF_RPATH=1
         dontFixLibtool=1