FTBFS: Multiple rules generated for _build/default/_doc/hostnet/index.html

[gerboland]

Hey,
I've checked out today's vpnkit (e203f93), following the README installed the opam dependencies ok, but when trying to build I hit this barrier:

$ make
[ERROR] No package named hostnet found.
opam config subst src/bin/depends.ml || true
cp src/bin/depends.ml src/bin/depends.tmp
sed -e 's/££VERSION££/e203f930f850bef3e4514a19abe441f466630c8c/g' src/bin/depends.tmp > src/bin/depends.ml
cp src/bin/depends.ml src/bin/depends.tmp
sed -e 's/££HOSTNET_PINNED££//g' src/bin/depends.tmp > src/bin/depends.ml
cp src/bin/depends.ml src/bin/depends.tmp
sed -e 's/££HVSOCK_PINNED££//g' src/bin/depends.tmp > src/bin/depends.ml
jbuilder build src/bin/main.exe
Multiple rules generated for _build/default/_doc/hostnet/index.html
make: *** [vpnkit.exe] Error 1

I'm trying to understand jbuilder, but if someone can see what I'm missing, I'd appreciate a hint.

Here's my opam config report: https://pastebin.com/4mktVd6x
and installed deps: https://pastebin.com/zxip0JqT

Thanks
-G

[gerboland]

Well this helps: https://pastebin.com/FLkRURxy but I don't know enough to understand why.

With that patch, and ensuring cstruct is at version 2.4.1 (version 3 is out), it all compiles ok.

[samoht]

Unfortunately, there are few more steps to do before running make, as described In the README, as vpnkit vendors its dependencies in the repo/ directory. It would be nice if the repo were buildable with upstream components, but we are not there yet.

The error you see is because jbuilder is scanning that repo directory -- the right way to avoid this is to add a jbuild-ignore file at the root of the repository, containing:

repo

Let me know if you manage to go further -- it would be nice if vpnkit was indeed easier to build.

[gerboland]

(Balated) Thanks for the feedback. Agreed building not super easy, I'll see if I can help at all on that

[yuce]

Thanks to the comments in this thread, I was able to compile vpnkit on MacOS. Here is what worked for me for anyone else struggling to compile it on MacOS. I assume brew is installed and up-to-date.

Install opam:

brew install opam

Update pkg-config. I had 0.28 which didn't work, 0.29.2 works:

brew upgrade pkg-config

Latest Ocaml 4.05 is not supported, so switch to an older version:

opam switch 4.04.2

Update the environment for the switched OCaml:

eval `opam config`

Clone vpnkit repo and cd to it:

https://github.com/moby/vpnkit.git
cd vpnkit

Get the dependencies:

opam remote add vpnkit ./repo/darwin
opam install --deps-only slirp
opam install cstruct=2.4.1
opam install uwt

Ignore the repo dir:

printf "repo\n" > ./repo/jbuild-ignore

You are now ready to compile:

make

[samoht]

The build instructions specified in the README should now work properly:

cd [path to vpnkit source]
opam remote add vpnkit ./repo/darwin
opam install --deps-only vpnkit
make

Please re-open if that's not the case.