diff --git a/ocaml-411.patch b/ocaml-411.patch
new file mode 100644
index 0000000..575560e
--- /dev/null
+++ b/ocaml-411.patch
@@ -0,0 +1,11 @@
+--- ppx_deriving_yojson-3.5.2.old/src/ppx_deriving_yojson.cppo.ml	2020-02-20 21:01:12.000000000 +0000
++++ ppx_deriving_yojson-3.5.new/src/ppx_deriving_yojson.cppo.ml	2020-04-22 18:15:35.242395194 +0100
+@@ -385,7 +385,7 @@
+       let ty = Typ.poly poly_vars (polymorphize_ser [%type: [%t typ] -> Yojson.Safe.t]) in
+       let default_fun =
+         let type_path = String.concat "." (path @ [type_decl.ptype_name.txt]) in
+-        let e_type_path = Exp.constant (Pconst_string (type_path, None)) in
++        let e_type_path = Exp.constant (Pconst_string (type_path, Location.none, None)) in
+         [%expr fun _ ->
+           invalid_arg ("to_yojson: Maybe a [@@deriving yojson] is missing when extending the type "^
+                        [%e e_type_path])]
diff --git a/ocaml-ppx-deriving-yojson.spec b/ocaml-ppx-deriving-yojson.spec
index ddf19e1..1ad89e7 100644
--- a/ocaml-ppx-deriving-yojson.spec
+++ b/ocaml-ppx-deriving-yojson.spec
@@ -14,6 +14,9 @@ License:        MIT
 URL:            https://github.com/ocaml-ppx/%{upname}
 Source0:        %{url}/archive/v%{version}/%{upname}-%{version}.tar.gz
 
+# Fix for OCaml 4.11.  Sent upstream 2020-04-22.
+Patch1:         ocaml-411.patch
+
 BuildRequires:  ocaml >= 4.04.0
 BuildRequires:  ocaml-biniou-devel
 BuildRequires:  ocaml-cppo