--- bin/gwrepl/mk_data.ml.orig	2024-04-21 10:35:20
+++ bin/gwrepl/mk_data.ml	2024-04-21 10:33:38
@@ -43,35 +43,8 @@
   before_after_ocaml_version "5.1.0" ~before ~after
 
 let () =
-  let opam_switch_prefix = Sys.getenv "OPAM_SWITCH_PREFIX" in
-  let opam_switch_prefix_lib = opam_switch_prefix // "lib" in
-  let ocaml_stdlib_directory =
-    let output_filename, error_filename =
-      let temporary_filename = Filename.temp_file "gwrepl_" "_ocaml_stdlib" in
-      (temporary_filename ^ ".out", temporary_filename ^ ".err")
-    in
-    let command =
-      let double_quote_if_win32 = if Sys.win32 then "\"" else "" in
-      Printf.sprintf "%sopam exec -- ocamlc -where > %s 2> %s%s"
-        double_quote_if_win32
-        (Filename.quote output_filename)
-        (Filename.quote error_filename)
-        double_quote_if_win32
-    in
-    let exit_code = Sys.command command in
-    if exit_code <> 0 then
-      failwith
-      @@ Printf.sprintf "Command '%s' failed:\nexit code: %d\nerror: %s" command
-           exit_code
-           (String.concat "\n" (read_lines @@ open_in error_filename))
-    else
-      match read_lines @@ open_in output_filename with
-      | ([] | _ :: _ :: _) as lines ->
-          failwith
-          @@ Printf.sprintf "Unexpected output of command '%s':\n%s" command
-               (String.concat "\n" lines)
-      | [ line ] -> line
-  in
+  let mp_ocaml_site_lib = "__MACPORTS_PREFIX__/lib/ocaml/site-lib/" in
+  let ocaml_stdlib_directory = "__MACPORTS_PREFIX__/lib/ocaml/" in
 
   let dune_root, root, (directories0, files0) =
     let ic = open_in ".depend" in
@@ -93,8 +66,8 @@
                (String.length fn - String.length prefix))
         else None
       in
-      match aux opam_switch_prefix_lib with
-      | Some x -> Some (`opam (opam_switch_prefix_lib, x))
+      match aux mp_ocaml_site_lib with
+      | Some x -> Some (`opam (mp_ocaml_site_lib, x))
       | None -> ( match aux root with Some x -> Some (`root x) | None -> None)
     in
     ( dune_root,
@@ -219,7 +192,7 @@
                ~after:(fun () -> "dllunixbyt.so") );
       ];
     if_sosa_zarith out (fun () ->
-        aux (opam_switch_prefix_lib, "stublibs" // "dllzarith.so")));
+        aux (mp_ocaml_site_lib, "stublibs" // "dllzarith.so")));
   Printf.fprintf out {||];;|};
   let b = Buffer.create 1024 in
   let aux =