Builds fail on some machines with 0.5.1

[talex5]

With 0.5.1, my project sometimes fails to compile. It seems to depend on the order of directory entries returned by readdir.

bisecting, it appears this was fixed in d1d90dda649f412ae6af3d0e2dae040cafae065b - would be nice to have a new release.

My test-case is:

docker run --rm -it ocaml/opam:debian-stable_ocaml-4.03.0
git clone https://github.com/talex5/test-namespaces
opam install -y ocamlfind namespaces
cd test-namespaces 
make

This fails on some machines and works on others, even with the exact same Docker image (just a different Linux kernel).

The output on failure is:

opam@59d85fb885a7:~/test-namespaces$ make
ocamlbuild -use-ocamlfind -plugin-tag "package(namespaces)" main.native
+ ocamlfind ocamlopt -package unix -package ocamlbuild -linkpkg -package namespaces myocamlbuild.ml /home/opam/.opam/4.03.0/lib/ocamlbuild/ocamlbuild.cmx -o myocamlbuild
File "_none_", line 1:
Warning 58: no cmx file was found in path for module Namespaces, and its interface was not compiled with -opaque
Finished, 1 target (0 cached) in 00:00:00.
+ ocamlfind ocamlopt -linkpkg _namespaces.cmxa main.cmx -o main.native
File "_none_", line 1:
Error: No implementations provided for the following modules:
         A__foo referenced from _namespaces.cmxa(B__bar)
Command exited with code 2.
Compilation unsuccessful after building 28 targets (0 cached) in 00:00:00.
Makefile:4: recipe for target 'binary' failed
make: *** [binary] Error 10