unison-2.48 build fails with latest ocaml and flexdll (attn: Achim)

[Yaakov Selkowitz]

On 2017-03-31 12:00, Andrew Schulman wrote:
>> On 2017-02-24 12:15, Andrew Schulman wrote:
>> Could you try this again with the OCaml 4.04.0 stack I just uploaded,
>> and see if this is still an issue?
>
> Yes, with OCaml 4.04.0 the build of unison2.49 still fails with
>
>   flexdll error: cannot relocate RELOC_REL32, target is too far:
> 0xfffffffc185d8b5f  0x185d8b5f
>
> Running
>
>   rebase -b 0x06440000 /usr/lib/ocaml/stublibs/dllunix.so
>   rebase -b 0x06510000 /usr/lib/ocaml/stublibs/dllcamlstr.so
>
> as before fixed the flexdll error.

Achim, I think /usr/lib/ocaml needs to be ignored by autorebase; 
flexlink'ed DLLs are loaded very differently, and rebasing seems to 
break them.

> Then I got a different build error, but
> I'll ask on the unison list about that.

Is 2.49 a stable version?  It seems neither Fedora nor Debian have 
packaged it.  I was able to build the latest 2.48 OOTB, and 2.40 and 
2.45 with this patch:

http://pkgs.fedoraproject.org/cgit/rpms/unison240.git/tree/unison-2.40.128-ocaml-4.04.patch

> The build of orpie also failed, but for a different reason. It needed
> ocaml-camlp4, but when I installed that and tried again I got
>
>   ocamlopt.opt -c -pp camlp4o -I ./curses -I ./gsl -I ./units -thread
> curses_assist.ml
>   >> Fatal error: OCaml and preprocessor have incompatible versions

Oops, it seems there were some old curr:/prev: tags on ocaml-camlp4.  I 
removed those, so please try again with 4.04+1-1.

-- 
Yaakov