ocamlPackages.ocaml_gettext: fix for OCaml 5.4

pkgs/development/ocaml-modules/ocaml-gettext/default.nix

@@ -4,27 +4,36 @@
   fetchpatch,
   applyPatches,
   buildDunePackage,
+  ocaml,
   cppo,
   gettext,
   fileutils,
   ounit2,
 }:
 
-buildDunePackage rec {
+buildDunePackage (finalAttrs: {
   pname = "gettext";
   version = "0.5.0";
 
   src = applyPatches {
     src = fetchurl {
-      url = "https://github.com/gildor478/ocaml-gettext/releases/download/v${version}/gettext-${version}.tbz";
+      url = "https://github.com/gildor478/ocaml-gettext/releases/download/v${finalAttrs.version}/gettext-${finalAttrs.version}.tbz";
       hash = "sha256-CN2d9Vsq8YOOIxK+S+lCtDddvBjCrtDKGSRIh1DjT10=";
     };
-    # Disable dune sites
-    # See https://github.com/gildor478/ocaml-gettext/pull/37
-    patches = fetchpatch {
-      url = "https://github.com/gildor478/ocaml-gettext/commit/5462396bee53cb13d8d6fde4c6d430412a17b64d.patch";
-      hash = "sha256-tOR+xgZTadvNeQpZnFTJEvZglK8P+ySvYnE3c1VWvKQ=";
-    };
+    patches = [
+      # Disable dune sites
+      # See https://github.com/gildor478/ocaml-gettext/pull/37
+      (fetchpatch {
+        url = "https://github.com/gildor478/ocaml-gettext/commit/5462396bee53cb13d8d6fde4c6d430412a17b64d.patch";
+        hash = "sha256-tOR+xgZTadvNeQpZnFTJEvZglK8P+ySvYnE3c1VWvKQ=";
+      })
+    ]
+    # Compatibility with OCaml ≥ 5.4
+    # See https://github.com/gildor478/ocaml-gettext/pull/41
+    ++ lib.optional (lib.versionAtLeast ocaml.version "5.4") (fetchpatch {
+      url = "https://github.com/gildor478/ocaml-gettext/commit/5d521981e39dcaeada6bbe7b15c5432d6de5d33c.patch";
+      hash = "sha256-82ajmpyXSd2RdVq/ND4lS8PIugRSkKe5oL8BL9CsLo4=";
+    });
   };
 
   nativeBuildInputs = [ cppo ];
@@ -46,4 +55,4 @@ buildDunePackage rec {
     maintainers = [ ];
     mainProgram = "ocaml-gettext";
   };
-}
+})