Support new locations of unix, str and dynlink

[dra27]

Updates ocamlbuild for compatibility with the changes proposed in ocaml/ocaml#11198 in order to silence the alert displayed by that PR.

[gasche]

Is ocaml_otherlibs_lib "foo" not something you can already do with ocaml_lib ~extern:true ~dir:"+foo" "foo"? I have the impression that the latter already adds ocaml, compile, use_foo: -I +foo .

Documentation:

ocamlbuild/src/signatures.mli

Lines 800 to 815 in e11720f

	(** [ocaml_lib <options> library_pathname] Declare an ocaml library.
	This informs ocamlbuild and produce tags to use the library;
	they are named by default use_#{library_name}.
	Example: [ocaml_lib "foo/bar"] will setup the tag use_bar.
	At link time it will include:
	foo/bar.cma or foo/bar.cmxa
	@param dir supply the [~dir:"boo"] option to add '-I boo'
	at link and compile time.
	@param extern use ~extern:true for non-ocamlbuild handled libraries.
	Set this to add libraries whose sources are not in your project.
	@param byte use ~byte:false to disable byte mode.
	@param native use ~native:false to disable native mode.
	@param tag_name Use ~tag_name:"usebar" to override the default
	tag name. *)
	val ocaml_lib :

Implementation:

ocamlbuild/src/ocaml_utils.ml

Lines 100 to 134 in e11720f

	let ocaml_lib ?(extern=false) ?(byte=true) ?(native=true) ?dir ?tag_name libpath =
	let add_dir x =
	match dir with
	| Some dir -> S[A"-I"; P dir; x]
	| None -> x
	in
	let tag_name =
	match tag_name with
	| Some x -> x
	| None -> "use_" ^ Pathname.basename libpath
	in
	let flag_and_dep tags lib =
	flag tags (add_dir (A lib));
	if not extern then dep tags [lib] (* cannot happen? *)
	in
	Hashtbl.replace info_libraries tag_name (libpath, extern);
	(* adding [tag_name] to [info_libraries] will make this tag
	affect include-dir lookups, so it is used even if not
	mentioned explicitly in any rule. *)
	Flags.mark_tag_used tag_name;
	if extern then begin
	if byte then
	flag_and_dep ["ocaml"; tag_name; "link"; "byte"] (libpath^".cma");
	if native then
	flag_and_dep ["ocaml"; tag_name; "link"; "native"] (libpath^".cmxa");
	end else begin
	if not byte && not native then
	invalid_arg "ocaml_lib: ~byte:false or ~native:false only works with ~extern:true";
	end;
	match dir with
	| None -> ()
	| Some dir ->
	List.iter
	(fun x -> flag ["ocaml"; tag_name; x] (S[A"-I"; P dir]))
	["compile"; "doc"; "infer_interface"]

[gasche]

(Maybe one needs ocaml_lib ~extern:true ~dir:"+foo" "foo/foo"?)

[hhugo]

This can be closed, fixed in #328