use pclock, rather than clock, needed for mirage 3.0

[yomimono]

No description provided.

[yomimono]

@djs55, this PR causes the xen backend tests to fail on reinstalling c3 (see here). I don't understand that bit of the site very well; before I dig in, do you have some sense of what might need to be fixed?

[djs55]

This is very odd, I've never seen it before:

mirage =>
  cd /home/travis/build/mirage/mirage-www/src && ocamlbuild -use-ocamlfind -tags annot,bin_annot -pkg mirage config.cmxs
Fatal error: exception (Invalid_argument "[ocamlgraph] in_degree")
make: *** [configure] Error 2
'OPAMYES=1 export OPAMYES; set -ex; MODE=$MIRAGE_BACKEND make configure' exited 2. Terminating with 2

[yomimono]

OK, thanks for taking a look; I'll see whether I can figure it out.

[yomimono]

I can reproduce this locally when supplying --tls false to mirage configure -f src/config.ml. --tls true doesn't trigger the Ocamlgraph exception. The default value of tls if not supplied is false, and supplying no --tls argument at all results in a successful run of mirage configure.

[yomimono]

Looking at the mirage describe --dot output when tls is unspecified, it seems that the default falseness of tls is not propagated and there are still nodes in the graph that expect to be supplied with the value of tls, whether true or false. Notably, there are child nodes under secrets-kv_ro which can only be reached from Dispatch_tls, which we'd expect not to see when tls is false. Orphaning these nodes would violate the invariants stated in Functoria_graph, which would lead to the kind of problem we'd expect to generate an exception like Invalid_argument "[ocamlgraph] in_degree".

It seems that providing mirage configure -t xen --tls false --secrets-kv_ro crunch (or some other option for --secrets-kv_ro) results in successful completion of mirage configure, so perhaps we're on the right track here?

[yomimono]

ocaml-fat had constraints preventing installation of cstruct >= 2.0.0. mirage/ocaml-fat#44 should fix this, and hopefully allow tests to pass with the mirage-dev repo.