Fix Unix already loaded error

[Julow]

While migrating from Lwt_log to Logs, I got the basic eliom template fails with this message:

ocsigenserver: [ERROR] Fatal - While loading /nix/store/24p21ifnh3r3kb7fd69lc7pc2zmr9avz-ocaml-5.2.1/lib/ocaml/unix/unix.cma: The module `Unix' is already loaded (either by the main program or a previously-dynlinked library)

It seems that ocsigenserver now links Unix in a different order or perhaps Unix became a transitive dependency to something else?
Anyway, I think this error can be ignored.

[Julow]

On master, the loaded modules are (15 lines):

ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/ocsigenserver/ext/staticmod/staticmod.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/dbm/dbm.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/ocsipersist-lib/ocsipersist_lib.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/ocsipersist-dbm/__private__/ocsipersist_dbmtypes/ocsipersist_dbmtypes.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/ocsipersist-dbm/settings/ocsipersist_dbm_settings.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/ocsipersist-dbm/ocsipersist_dbm.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/ocsipersist-dbm-config/ocsipersist_dbm_config.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/js_of_ocaml/deriving/js_of_ocaml_deriving.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/react/react.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/lwt_react/lwt_react.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/uutf/uutf.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/tyxml/functor/tyxml_f.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/tyxml/tyxml.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/eliom/server/eliom_server.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/juloo/.opam/5.2-ocsigen-next/lib/ppx_deriving/runtime/ppx_deriving_runtime.cma

On #256 there are 163 modules being loaded. The new "cannot be loaded again" message is generated 143 times.
I tried with removing syslog support to check if it introduced new dependencies but the number of loaded modules is similar.

Is here something in #256 that changes the dependency of ocsigenserver extensions ?

[vouillon]

I was not able to reproduce the issue. I get this output:

$ ocsigenserver  -c local/etc/toto/toto-test.conf --debug
ocsigenserver: ocsigen:dynlink: Dependencies of ocsigenserver.ext.staticmod: ocsigenserver.ext.staticmod
ocsigenserver: ocsigen:ocsipersist:dbm: Initializing ...
ocsigenserver: ocsigen:dynlink: Needed: /home/jerome/.opam/5.3.0/lib/ocsigenserver/ext/staticmod/staticmod.cma
ocsigenserver: ocsigen:ocsipersist:dbm: Launching a new Ocsidbm process: ocsidbm on directory local/var/data/toto/ocsipersist.
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ocsigenserver/ext/staticmod/staticmod.cma
ocsigenserver: ocsigen:dynlink: Dependencies of ocsipersist-dbm-config: dbm, ocsipersist-lib, ocsipersist, ocsipersist-dbm.__private__.ocsipersist_dbmtypes, ocsipersist-dbm.settings, ocsipersist-dbm, ocsipersist-dbm-config
ocsigenserver: ocsigen:dynlink: Needed: /home/jerome/.opam/5.3.0/lib/dbm/dbm.cma, /home/jerome/.opam/5.3.0/lib/ocsipersist-lib/ocsipersist_lib.cma, /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm/__private__/ocsipersist_dbmtypes/ocsipersist_dbmtypes.cma, /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm/settings/ocsipersist_dbm_settings.cma, /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm/ocsipersist_dbm.cma, /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm-config/ocsipersist_dbm_config.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/dbm/dbm.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ocsipersist-lib/ocsipersist_lib.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm/__private__/ocsipersist_dbmtypes/ocsipersist_dbmtypes.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm/settings/ocsipersist_dbm_settings.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm/ocsipersist_dbm.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ocsipersist-dbm-config/ocsipersist_dbm_config.cma
ocsigenserver: ocsigen:ocsipersist:dbm: ...Initialization complete
ocsigenserver: ocsigen:dynlink: Dependencies of eliom.server: js_of_ocaml.deriving, react, lwt_react, ocsipersist-lib, ocsipersist, uutf, tyxml.functor, tyxml, eliom.server
ocsigenserver: ocsigen:dynlink: Needed: /home/jerome/.opam/5.3.0/lib/js_of_ocaml/deriving/js_of_ocaml_deriving.cma, /home/jerome/.opam/5.3.0/lib/react/react.cma, /home/jerome/.opam/5.3.0/lib/lwt_react/lwt_react.cma, /home/jerome/.opam/5.3.0/lib/ocsipersist-lib/ocsipersist_lib.cma, /home/jerome/.opam/5.3.0/lib/uutf/uutf.cma, /home/jerome/.opam/5.3.0/lib/tyxml/functor/tyxml_f.cma, /home/jerome/.opam/5.3.0/lib/tyxml/tyxml.cma, /home/jerome/.opam/5.3.0/lib/eliom/server/eliom_server.cma
ocsigenserver: ocsigen:config: While parsing config file, tag <host>: No defaulthostname, assuming it is "catalpa"
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/js_of_ocaml/deriving/js_of_ocaml_deriving.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/react/react.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/lwt_react/lwt_react.cma
ocsigenserver: ocsigen:dynlink: Extension /home/jerome/.opam/5.3.0/lib/ocsipersist-lib/ocsipersist_lib.cma already loaded
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/uutf/uutf.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/tyxml/functor/tyxml_f.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/tyxml/tyxml.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/eliom/server/eliom_server.cma
ocsigenserver: ocsigen:dynlink: Dependencies of logs: 
ocsigenserver: ocsigen:dynlink: Needed: 
ocsigenserver: ocsigen:dynlink: Dependencies of logs-syslog: ptime, syslog-message, logs-syslog
ocsigenserver: ocsigen:dynlink: Needed: /home/jerome/.opam/5.3.0/lib/ptime/ptime.cma, /home/jerome/.opam/5.3.0/lib/syslog-message/syslog_message.cma, /home/jerome/.opam/5.3.0/lib/logs-syslog/logs_syslog.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ptime/ptime.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/syslog-message/syslog_message.cma
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/logs-syslog/logs_syslog.cma
ocsigenserver: ocsigen:dynlink: Dependencies of js_of_ocaml-ppx_deriving_json: js_of_ocaml.deriving, ppx_deriving.runtime, ppx_deriving, js_of_ocaml-ppx_deriving_json
ocsigenserver: ocsigen:dynlink: Needed: /home/jerome/.opam/5.3.0/lib/js_of_ocaml/deriving/js_of_ocaml_deriving.cma, /home/jerome/.opam/5.3.0/lib/ppx_deriving/runtime/ppx_deriving_runtime.cma
ocsigenserver: ocsigen:dynlink: Extension /home/jerome/.opam/5.3.0/lib/js_of_ocaml/deriving/js_of_ocaml_deriving.cma already loaded
ocsigenserver: ocsigen:dynlink: Loading extension /home/jerome/.opam/5.3.0/lib/ppx_deriving/runtime/ppx_deriving_runtime.cma
ocsigenserver: ocsigen:mimetype: Loading mime types in '/home/jerome/.opam/5.3.0/lib/ocsigenserver/etc/ocsigenserver/mime.types'
ocsigenserver: ocsigen:dynlink: Loading local/lib/toto/toto.cma (will be reloaded every times)

[Julow]

@vouillon Did you try with #256 ?

[vouillon]

Oh, I did not try with the right branch, indeed. See my comment on #256.

[Julow]

Thanks! I'll fix the bug in that PR.