On Thu, Dec 12, 2024 at 8:46 AM Andreas Rossberg <rossberg@mpi-sws.org> wrote:
Good to know, thank you for the suggestions!

However, I’m afraid that hacking the compiler and tool chain for this purpose is not an option — that would require everybody else who wants to build the project to do the same, which is infeasible.

It’s a bit disappointing that there seems to be no easy solution for this problem. I would expect it to be a common pain point for folks using OCaml 5 to develop and publish application binaries for Windows. Or am I just alien?

OCaml's dependency on winpthreads will probably go away in the near future, see https://github.com/ocaml/ocaml/pull/13416 .

But, more generally, static linking of C libraries is getting more and more difficult -- even from C, not just OCaml.  For example, under Linux, it's essentially impossible to statically link with the glibc C standard library; a musl-based distribution must be used if static linking is desired.  It looks as if the consensus was that static linking of libraries is a bad idea and must be prevented.  I don't think it is, but that's something way beyond OCaml's control.

Best,

- Xavier Leroy


 

Cheers,
/Andreas


> On 2. Dec 2024, at 09:25, Antonin Décimo <antonin.decimo@gmail.com> wrote:
>
>> Regarding OCaml 5.3/mingw64 you shouldn't need to have to do anything with libwinpthreads because it's only used for the msvc port, not the mingw one.
>
> That is not quite exact, winpthreads is used with mingw-w64, but found
> in the system installation, and linked to. It is vendored for the MSVC
> port and we *statically* link into the runtime only the parts we're
> interested in.
>
> To statically link with winpthreads, I suggest you do all of it manually:
> - clone winpthreads sources at https://github.com/mingw-w64/mingw-w64,
> go to mingw-w64-libraries/winpthreads, and build a static version of
> the library with your preferred toolchain;
>
> - hack the OCaml compiler / Makefile to *not* use `-lpthreads`:
>  https://github.com/ocaml/ocaml/blob/5a5eb481c7a9d0f039e3169aa8ed19c9b926e982/configure.ac#L2372-L2373
>  Maybe it's just sufficient to set PTHREAD_LIBS when invoking
> configure; however seeing this line makes me think that winpthreads is
> already statically linked with the runtime.
>
>     PTHREAD_LIBS="-l:libpthread.a $link_gcc_eh"]
>
>  Haven't dug further.
>
> -- Antonin