RE: [Caml-list] Flexdll circular dependency fix uses system provided flexdll.h [was: opam-cross-windows]

[David Allsopp <dra-news@metastack.com>]

Michael Soegtrop wrote:
> Dear David,
> 
> I just managed now to test the flexdll dependency fix in 4.03.0 you
> mentioned in your post from March 15th:
> 
> >  1. Ensure FlexDLL sources are in flexdll/ in the OCaml build tree
> >	1a. If you're building from a git clone, issue git submodule update
> --init
> >	1b. If you're building from a sources tarball, issue git clone >
> >https://github.com/alainfrisch/flexdll.git
> > 2. Follow usual configuration steps in config/  3. make -f Makefile.nt
> >flexdll world opt opt.opt install
> 
> It is much better than it was, but I think there is still a minor flaw in
> it. When compiling byterun/win32.c (from asmrun) in the make opt phase, it
> doesn't find flexdll.h because gcc doesn't have an -I ../flexdll. If I
> copy flexdll.h to a system include directory it works fine. Is it possible
> that you had a flexdll.h somewhere and the build took it from there rather
> than from the flexdll subfolder when you tried this?

I'm not convinced this is a fundamental flaw - I think it more likely that you have an existing flexlink in PATH, which will cause config/Makefile to pick up the wrong include directory. I think it likely if you study the failing command during make -f Makefile.nt opt you will see a -I pointing to your PATH'd flexlink.exe directory.

Does it work if you remove your system included flexdll.h and alter config/Makefile to delete the line FLEXDIR:= (a la https://github.com/dra27/opam-repository/blob/next-windows/packages/ocaml/ocaml.4.03.0/files/win.sh#L9)?

> Also I think specific versions of OCaml should copy specific versions of
> flexdll.

Yes and no - this is a bit like insisting that a given OCaml version be built with a specific version of gcc. At present, OCaml 3.11 (when flexlink was introduced) still builds just fine with trunk flexdll.

> A git clone of the trunk version might lead to unexpected effects
> in the future and it might be hard to reconstruct older OCaml versions
> later.

A git clone of trunk will use the version of flexdll configured at the time - that's how git submodules work (because it stores a commit SHA, not a branch).

Best,


D