Preprocessor error "Grammar.extend" with 2.0.3

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Install ocaml-bitstring-2.0.3
2. Pick any Foo.ml file
3.
ocamlfind ocamlc -package bitstring,bitstring.syntax -syntax bitstring.syntax 
-linkpkg Foo.ml -o Foo.exe

or

ocamlfind ocamldep -package bitstring,bitstring.syntax -syntax bitstring.syntax 
-modules Foo.ml

What is the expected output? What do you see instead?

Expected: success

Instead:

% ocamlfind ocamlc -package bitstring,bitstring.syntax -syntax bitstring.syntax 
-linkpkg Foo.ml -o Foo.exe
No level labelled ";" in entry "expr"
Failure: "Grammar.extend"
File "Foo.ml", line 1, characters 0-1:
Error: Preprocessor error

% ocamlfind ocamldep -package bitstring,bitstring.syntax -syntax 
bitstring.syntax -modules Foo.ml 
No level labelled ";" in entry "expr"
Failure: "Grammar.extend"
Preprocessing error on file Foo.ml

Specifically, its "-syntax bitstring.syntax" that is causing me the error. If I 
remove it, everything goes fine. If I uninstall 2.0.3 and install 2.0.2 
instead, the flag does not cause this error.

What version of the product are you using? On what operating system?

ocaml-bitstring 2.0.3 only (no problem with 2.0.2)
OCaml 3.12.1

This might not be a bug and be just me doing something wrong. Also, all tests 
pass in the build directory, it's only when I "make install" and try to compile 
some of my files that the errors arise.

Original issue reported on code.google.com by valentin.robert.42 on 27 Jan 2012 at 2:56

[GoogleCodeExporter]

Adding:
syntax(camlp4o)
to the _tags solve the problem.

cf.
https://groups.google.com/forum/?fromgroups#!topic/bitstring/jToWgrzZ8Z4
http://forge.ocamlcore.org/tracker/index.php?func=detail&aid=588&group_id=54&ati
d=291

Original comment by valentin.robert.42 on 28 Mar 2012 at 9:56