Thanks for all the responses. The problem turned out to be the simple one
mentioned by Philippe. I just forgot to install PG'Ocaml. It would be nice
if findlib could give error messages about missing packages that are clearly
in the dependency list.

On Sun, Oct 9, 2011 at 8:23 AM, Christophe Papazian <
christophe.papazian@gmail.com> wrote:

> I got this problem a few days ago, and need a quick fix.
> Everything was installed but after an upgrade I got the same kind of error.
> To avoid the problem, i drop the "-syntax" parameter and replace it with
> "-pp" :
>
> What *should* work for me : ocamlfind ocamlc -package js_of_ocaml -syntax
> camlp4o
> What's *really* work for me : ocamlfind ocamlc -package js_of_ocaml -pp
> "camlp4o -I /path/to/js_of_ocaml pa_js.cmo"
>
> Hope this help
>
>  Christophe
>
> Le 9 oct. 11 à 00:46, Ashish Agarwal a écrit :
>
>
>  I get the error below after reinstalling OCaml with the latest version
>> with GODI. My code has not changed, so I'm wondering if there is a change to
>> ocamlbuild or ocamlfind that is causing this. The issue appears to be that
>> -package camlp4 should be included in the ocamlfind command but it is not.
>>
>> The section "Does Findlib support camlp4" in the findlib User's Guide
>> discusses the 'preprocessor' variable, but I can't figure out how exactly
>> how to adjust my META file or whether I really need to since it was working
>> before.
>>
>> ocamlbuild sequme.cma sequme.cmxa sequme.cmxs
>> Finished, 0 targets (0 cached) in 00:00:00.
>> + ocamlfind ocamldep -package batteries -package biocaml -package
>> netclient -package netstring -package shell -package sqlite3 -syntax camlp4o
>> -modules sequme/bowtie.mli > sequme/bowtie.mli.depends
>> ocamlfind: When using -syntax, the META variable 'preprocessor' must be
>> set
>> Command exited with code 2.
>>
>> --- META ---
>> requires = "netstring shell netclient batteries biocaml pgocaml"
>> version = "0.0"
>> archive(byte) = "sequme.cma"
>> archive(native) = "sequme.cmxa"
>>
>>
>