make it work also on 32-bit machines

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@13525 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
ignore .exe files

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@13526 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
continuation of r13523

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@13527 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02