Have you considered following the "standard" instructions for building a
custom toplevel:
http://caml.inria.fr/pub/docs/manual-ocaml-4.03/toplevel.html#sec275?

Also, to the best of my knowledge, the standard toplevel (ocaml) is not a
native code application.  There _is_ a native toplevel called ocamlnat, but
as of 4.03 (IIRC) it was still undocumented, and "non-standard."  If your
goal is simply to produce a stand-alone "executable" which packages the
byte code an a COFF/ELF binary into a single file, then you can use the
"-custom" flag as documented in Chapters 8 and 19 of the manual I linked to
above.

Finally, if you are using the Cygwin version of OCaml you cannot avoid
Cygwin: your executable will be linked with cygwin.dll, and you will need
to have that present in order to start your executable.  If you wish to
produce an executable that doesn't require Cygwin at run-time, you need to
use one of the non-Cygwin OCaml compilers: on Windows, you have a choice
between MSVC and MingGW.  That is documented in the README.win32 that comes
with the OCaml distribution:
https://github.com/ocaml/ocaml/blob/4.03/README.win32.adoc

Does this help, or do you have further questions?

-- 
Best,
Zhenya

On Tue, Apr 18, 2017 at 3:21 AM, <paul.lachat@edu.univ-fcomte.fr> wrote:

> Hello,
>
> I've change the toplevel of Ocaml to replace the standard input and output
> by named pipes on Windows.
>
> To achieve this, I've change the toploop.ml (https://github.com/ocaml/
> ocaml/blob/trunk/toplevel/toploop.ml) to include the named pipes
> of Ocamlnet (http://projects.camlcity.org/projects/dl/ocamlnet-4.1.2/
> doc/html-main/Netsys_win32.html#1_Supportfornamedpipes).
>
> After that, I tried to understand how I could compile this custom toplevel.
> I want to compile the toplevel to have a .exe, so I could avoid using
> Cygwin to launch the application.
>
> I've run the makefile of the git repository of Ocaml and tried to follow
> the sequence of compilation for the toplevel.
> I use ocamlopt to have a native aplication and ocamlfind to link
> toploop.ml with the library ocamlnet
> (via the package netsys where the win32 named pipe are defined) and unix
> for catching exceptions.
>
> I use Opam : 1.3.0~dev, Ocaml : 4.03.0 and Cygwin on Windows 7.
>
> So I write a Makefile (see the attachement) and when I launch it, I get
> this :
> ______________________________________________________________________
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c genprintval.mli
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c genprintval.ml
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c toploop.mli
> ocamlfind ocamlopt -g -I +compiler-libs ocamlcommon.cmxa
> ocamlbytecomp.cmxa ocamlcommon.a ocamlbytecomp.a -c toploop.ml -linkpkg
> -package netsys -package unix
> File "C:\OCaml64\home\Zar\toplevel_custom\_none_", line 1:
> Warning 58: no cmx file was found in path for module Netsys_win32, and its
> interface was not compiled with -opaque
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c trace.mli
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c trace.ml
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c topdirs.mli
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c topdirs.ml
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c topmain.mli
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c topmain.ml
> ocamlopt -g -I +compiler-libs -a -o tmp_ocamltoplevel.cmxa genprintval.cmx
> toploop.cmx trace.cmx topdirs.cmx topmain.cmx
> ocamlopt -g -I +compiler-libs ocamlcommon.cmxa ocamlbytecomp.cmxa
> ocamlcommon.a ocamlbytecomp.a -c topstart.ml
> ocamlfind ocamlopt -g -I +compiler-libs ocamlcommon.cmxa
> ocamlbytecomp.cmxa ocamlcommon.a ocamlbytecomp.a -linkall -o
> toplevel_custom.exe tmp_ocamltoplevel.cmxa topstart.cmx tmp_ocamltoplevel.a
> -linkpkg -package netsys -package unix
> ** Cannot resolve symbols for tmp_ocamltoplevel.a(topdirs.o):
> caml_get_current_environment
> File "caml_startup", line 1:
> Error: Error during linking
> ______________________________________________________________________
>
> But I don't know how to resolve this error.
> I find that "caml_get_current_environment" is defined in meta.c (and used
> in topdirs.ml)
> (https://github.com/ocaml/ocaml/search?utf8=%E2%9C%93&q=
> caml_get_current_environment+&type=)
> But I think that meta.c is in the ocamlbytecomp.cmxa library, so I don't
> know why the linker don't find the symbols.
>
> Someone know how to resolve this problem ?
>
> Thank you in advance !
>