diff --git a/src/driver/bin/odoc_driver.ml b/src/driver/bin/odoc_driver.ml
index d2386bd17d..44f94efde4 100644
--- a/src/driver/bin/odoc_driver.ml
+++ b/src/driver/bin/odoc_driver.ml
@@ -74,11 +74,28 @@ let run_inner ~odoc_dir ~odocl_dir ~index_dir ~mld_dir ~compile_grep ~link_grep
         let linked =
           Compile.link ~warnings_tags:packages ~custom_layout:false compiled
         in
+        let odoc_dirs =
+          List.fold_left
+            (fun acc pkg ->
+              let lib_dirs =
+                List.map
+                  (fun l -> Fpath.(odocl_dir // Odoc_unit.lib_dir pkg l))
+                  pkg.libraries
+              in
+              Fpath.Set.union acc (Fpath.Set.of_list lib_dirs))
+            Fpath.Set.empty all
+        in
+
+        Logs.debug (fun m ->
+            m "odoc_dirs: %a" (Fmt.Dump.list Fpath.pp)
+              (Fpath.Set.to_list odoc_dirs));
         let occurrence_file =
           let output =
-            Fpath.( / ) odoc_dir "occurrences-all.odoc-occurrences"
+            Fpath.( / ) odocl_dir "occurrences-all.odoc-occurrences"
+          in
+          let () =
+            Odoc.count_occurrences ~input:(Fpath.Set.to_list odoc_dirs) ~output
           in
-          let () = Odoc.count_occurrences ~input:[ odoc_dir ] ~output in
           output
         in
         let () =
diff --git a/src/driver/bin/odoc_driver_voodoo.ml b/src/driver/bin/odoc_driver_voodoo.ml
index d3f44614df..b6a00a8ae9 100644
--- a/src/driver/bin/odoc_driver_voodoo.ml
+++ b/src/driver/bin/odoc_driver_voodoo.ml
@@ -54,18 +54,24 @@ let run package_name blessed actions odoc_dir odocl_dir
   Logs.set_reporter (Logs_fmt.reporter ());
   Stats.init_nprocs nb_workers;
   let () = Worker_pool.start_workers env sw nb_workers in
+  let odocl_dir = Option.value odocl_dir ~default:odoc_dir in
 
-  let all, extra_paths, actions, generate_json, occurrence_file =
+  let all, extra_paths, actions, generate_json, occurrence_file, odocl_dirs =
     let pkg =
       let pkg_opt = Voodoo.find_pkg package_name ~blessed in
       match pkg_opt with Some pkg -> pkg | None -> exit 1
     in
     let all = Voodoo.of_voodoo pkg in
+    let odocl_dirs =
+      List.map
+        (fun l -> Fpath.(odocl_dir // Odoc_unit.lib_dir all l))
+        all.libraries
+    in
     let occurrence_file =
-      Fpath.(odoc_dir // Voodoo.occurrence_file_of_pkg pkg)
+      Fpath.(odocl_dir // Voodoo.occurrence_file_of_pkg pkg)
     in
     let extra_paths = Voodoo.extra_paths odoc_dir in
-    (all, extra_paths, actions, true, occurrence_file)
+    (all, extra_paths, actions, true, occurrence_file, odocl_dirs)
   in
 
   let all = Packages.remap_virtual [ all ] in
@@ -78,10 +84,7 @@ let run package_name blessed actions odoc_dir odocl_dir
     | _ -> failwith "Error, expecting singleton library in voodoo mode"
   in
   let units =
-    let dirs =
-      let odocl_dir = Option.value odocl_dir ~default:odoc_dir in
-      { Odoc_unit.odoc_dir; odocl_dir; index_dir; mld_dir }
-    in
+    let dirs = { Odoc_unit.odoc_dir; odocl_dir; index_dir; mld_dir } in
     Odoc_units_of.packages ~dirs ~indices_style:Voodoo ~extra_paths ~remap:false
       all
   in
@@ -101,7 +104,7 @@ let run package_name blessed actions odoc_dir odocl_dir
             compiled
         in
         let () =
-          Odoc.count_occurrences ~input:[ odoc_dir ] ~output:occurrence_file
+          Odoc.count_occurrences ~input:odocl_dirs ~output:occurrence_file
         in
         let () =
           Compile.html_generate ~occurrence_file ~remaps:[] ~generate_json