I believe there may be a bug in ocamlbuild when attempting to build
projects that require Jane Street's Core and related packages. Or perhaps
the error lies with Core, but I am no judge. Or perhaps my use of
ocamlbuild is flawed.

I started a simple project from scratch and with just 2 modules, and one of
them merely being dedicated to command line parsing, I could not get the
program to work with the most recent versions of OCaml (4.07.1), Core
(v.0.12.0), and ocamlbuild (0.14) available through opam (v2.0.0), all on a
Debian box. The project compiles but at runtime I get an error:

Fatal error: cannot load shared library dllcore_stubs
Reason: /<home_path>/.opam/4.07.1/lib/stublibs/dllcore_stubs.so: undefined
symbol: caml_exn_Invalid_argument

I double checked my environment variables. And this was not within an emacs
shell. In my Makefile I was passing -pkgs to ocamlbuild a list including
core, and I experimented with adding base and core_kernel, but that didn't
help. I slowly stripped away dependencies of anything related to Core, but
the error persisted until I completely removed Core. I was not even using
Core for command line parsing, nor in the module dedicated to command line
parsing. Compilation was always successful, however.

Finally, I gave up and downgraded to Ocaml 4.06.0 and Core 0.11.3 and the
same project compiles and runs just fine while including Core. Considering
that my version of ocamlbuild did not downgrade, I suspect something
changed over at Core...but still...it would be nice to support building
with Core even if the error lies there.   Has anyone else seen this issue?

Thank you.

-Paul