Remove the ?extra_targets argument of Build.run

Instead, use Hidden_targets

src/build.ml

@@ -211,14 +211,8 @@ let prog_and_args ?(dir=Path.root) prog args =
     >>>
     arr fst))
 
-let run ~context ?(dir=context.Context.build_dir) ?stdout_to ?(extra_targets=[])
-      prog args =
-  let extra_targets =
-    match stdout_to with
-    | None -> extra_targets
-    | Some fn -> fn :: extra_targets
-  in
-  let targets = Arg_spec.add_targets args extra_targets in
+let run ~context ?(dir=context.Context.build_dir) ?stdout_to prog args =
+  let targets = Arg_spec.add_targets args (Option.to_list stdout_to) in
   prog_and_args ~dir prog args
   >>>
   Targets targets

src/build.mli

@@ -133,7 +133,6 @@ val run
   :  context:Context.t
   -> ?dir:Path.t (* default: [context.build_dir] *)
   -> ?stdout_to:Path.t
-  -> ?extra_targets:Path.t list
   -> Action.Prog.t
   -> 'a Arg_spec.t list
   -> ('a, Action.t) t

src/gen_rules.ml

@@ -471,10 +471,6 @@ module Gen(P : Install_rules.Params) = struct
            (SC.expand_and_eval_set sctx ~scope ~dir lib.library_flags ~standard:[])
          >>>
          Build.run ~context:ctx (Ok compiler)
-           ~extra_targets:(
-             match mode with
-             | Byte -> []
-             | Native -> [lib_archive lib ~dir ~ext:ctx.ext_lib])
            [ Dyn (fun (_, _, flags, _) -> As flags)
            ; A "-a"; A "-o"; Target target
            ; As stubs_flags
@@ -484,6 +480,10 @@ module Gen(P : Install_rules.Params) = struct
                | Normal -> []
                | Ppx_deriver | Ppx_rewriter -> ["-linkall"])
            ; Dyn (fun (cm_files, _, _, _) -> Deps cm_files)
+           ; Hidden_targets
+               (match mode with
+                | Byte -> []
+                | Native -> [lib_archive lib ~dir ~ext:ctx.ext_lib])
            ]))
 
   let build_c_file (lib : Library.t) ~scope ~dir ~includes c_name =
@@ -652,7 +652,6 @@ module Gen(P : Install_rules.Params) = struct
                lib.c_library_flags ~standard:[]
              >>>
              Build.run ~context:ctx
-               ~extra_targets:targets
                (Ok ctx.ocamlmklib)
                [ As (Utils.g ())
                ; if custom then A "-custom" else As []
@@ -667,6 +666,7 @@ module Gen(P : Install_rules.Params) = struct
                    else
                      As cclibs
                  )
+               ; Hidden_targets targets
                ])
         in
         let static = stubs_archive lib ~dir in

src/menhir.ml

@@ -28,12 +28,12 @@ let gen_rules sctx ~dir ~scope (t : Jbuild.Menhir.t) =
   let menhir_binary =
     SC.resolve_program sctx "menhir" ~hint:"opam install menhir"
   in
-  (* [extra_targets] is to tell Jbuilder about generated files that do
-     not appear in the menhir command line. *)
-  let menhir ~extra_targets args =
+  (* [hidden_targets] is to tell Jbuilder about generated files that
+     do not appear in the menhir command line. *)
+  let menhir args =
     flags
     >>>
-    Build.run ~extra_targets
+    Build.run
       menhir_binary
       ~dir
       ~context:(SC.context sctx)
@@ -48,16 +48,16 @@ let gen_rules sctx ~dir ~scope (t : Jbuild.Menhir.t) =
     List.concat_map t.modules ~f:(fun name ->
       add_rule_get_targets (
         menhir
-          ~extra_targets:(targets name)
           [ Dyn (fun x -> As x)
           ; Dep (mly name)
+          ; Hidden_targets (targets name)
           ]))
   | Some merge_into ->
     add_rule_get_targets (
       menhir
-        ~extra_targets:(targets merge_into)
         [ A "--base" ; A merge_into
         ; Dyn (fun x -> As x)
         ; Deps (List.map ~f:mly t.modules)
-        ]
+        ; Hidden_targets (targets merge_into)
+      ]
     )

src/module_compilation.ml

@@ -70,13 +70,13 @@ let build_cm sctx ?sandbox ~dynlink ~flags ~cm_kind ~dep_graphs
           let fn = Option.value_exn (Target.cmt m ml_kind) in
           (fn :: other_targets, A "-bin-annot")
       in
-      let extra_targets = List.map other_targets ~f:(Target.file obj_dir) in
+      let hidden_targets = List.map other_targets ~f:(Target.file obj_dir) in
       if obj_dir <> dir then begin
         (* Symlink the object files in the original directory for
            backward compatibility *)
         let old_dst = Module.cm_file_unsafe m ~obj_dir:dir cm_kind in
         SC.add_rule sctx (Build.symlink ~src:dst ~dst:old_dst) ;
-        List.iter2 extra_targets other_targets ~f:(fun in_obj_dir target ->
+        List.iter2 hidden_targets other_targets ~f:(fun in_obj_dir target ->
           let in_dir = Target.file dir target in
           SC.add_rule sctx (Build.symlink ~src:in_obj_dir ~dst:in_dir))
       end;
@@ -91,7 +91,6 @@ let build_cm sctx ?sandbox ~dynlink ~flags ~cm_kind ~dep_graphs
          other_cm_files >>>
          Ocaml_flags.get_for_cm flags ~cm_kind >>>
          Build.run ~context:ctx (Ok compiler)
-           ~extra_targets
            [ Dyn (fun ocaml_flags -> As ocaml_flags)
            ; cmt_args
            ; A "-I"; Path obj_dir
@@ -105,6 +104,7 @@ let build_cm sctx ?sandbox ~dynlink ~flags ~cm_kind ~dep_graphs
                 As ["-open"; Module.Name.to_string m.name])
            ; A "-o"; Target dst
            ; A "-c"; Ml_kind.flag ml_kind; Dep src
+           ; Hidden_targets hidden_targets
            ])))
 
 let build_module sctx ?sandbox ~dynlink ~js_of_ocaml ~flags m ~scope ~dir

src/odoc.ml

@@ -175,11 +175,12 @@ module Gen (S : sig val sctx : SC.t end) = struct
          Build.remove_tree to_remove
          :: Build.mkdir odoc_file.html_dir
          :: Build.run ~context ~dir:Paths.html_root
-              odoc ~extra_targets:[odoc_file.html_file]
+              odoc
               [ A "html"
               ; odoc_include_flags requires
               ; A "-o"; Path Paths.html_root
               ; Dep odoc_file.odoc_input
+              ; Hidden_targets [odoc_file.html_file]
               ]
          :: jbuilder_keep
        )
@@ -213,9 +214,10 @@ module Gen (S : sig val sctx : SC.t end) = struct
     SC.add_rule sctx
       (Build.run ~context
          ~dir:context.build_dir
-         ~extra_targets:[css_file]
          odoc
-         [ A "css"; A "-o"; Path Paths.html_root ])
+         [ A "css"; A "-o"; Path Paths.html_root
+         ; Hidden_targets [css_file]
+         ])
 
   let sp = Printf.sprintf