1 files changed, 6 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/development/ocaml-modules/dum/default.nix b/nixpkgs/pkgs/development/ocaml-modules/dum/default.nix
index 3faef36e8ec4..43584461af18 100644
--- a/nixpkgs/pkgs/development/ocaml-modules/dum/default.nix
+++ b/nixpkgs/pkgs/development/ocaml-modules/dum/default.nix
@@ -13,6 +13,12 @@ stdenv.mkDerivation rec {
     sha256 = "0yrxl97szjc0s2ghngs346x3y0xszx2chidgzxk93frjjpsr1mlr";
   };
 
+  postPatch = ''
+      substituteInPlace "dum.ml" \
+      --replace "Lazy.lazy_is_val" "Lazy.is_val" \
+      --replace "Obj.final_tag" "Obj.custom_tag"
+  '';
+
   nativeBuildInputs = [ ocaml findlib ];
   propagatedBuildInputs = [ easy-format ];