Internal error when building tezos docs with Odoc.2.4.0

[NicNomadic]

Running dune build @doc on current Tezos master (commit 5f8f680327d6cae1d383c9865ef153c77ae38bd6) causes Odoc 2.4.0 to fail with the following internal error:

$ git clone https://gitlab.com/tezos/tezos.git
$ cd tezos
$ make build-deps
$ eval $(opam env)
$ opam install odoc.2.4.0
$ dune build @doc --stop-on-first-error
[…]
File "src/lib_distributed_plonk/distribution/.distribution.objs/byte/_unknown_", line 1, characters 0-0:
odoc: internal error, uncaught exception:
  Not_found
  Raised at Ident.find_same in file "typing/ident.ml", line 253, characters 6-21
  Called from Odoc_loader__Ident_env.find_exception_identifier in file "src/loader/ident_env.cppo.ml" (inlined), line 654, characters 2-35
  Called from Odoc_loader__Cmi.read_exception in file "src/loader/cmi.ml", line 775, characters 11-47
  Called from Odoc_loader__Cmi.read_signature_noenv.loop in file "src/loader/cmi.ml", line 1028, characters 18-50
  Called from Odoc_loader__Cmt.read_open in file "src/loader/cmt.ml", line 572, characters 21-96
  Called from Odoc_loader__Cmt.read_structure_item in file "src/loader/cmt.ml", line 520, characters 14-38
  Called from Odoc_loader__Cmt.read_structure.(fun) in file "src/loader/cmt.ml", line 592, characters 24-61
  Called from Stdlib__List.fold_left in file "list.ml", line 121, characters 24-34
  Called from Odoc_loader__Cmt.read_structure in file "src/loader/cmt.ml", line 590, characters 4-127
  Called from Odoc_loader__Cmt.read_module_expr in file "src/loader/cmt.ml", line 362, characters 21-83
  Called from Odoc_loader__Cmt.read_module_expr in file "src/loader/cmt.ml", line 380, characters 18-85
  Called from Odoc_loader__Cmt.read_module_expr_maybe_canonical in file "src/loader/cmt.ml", line 422, characters 10-53
  Called from Odoc_loader__Cmt.read_module_binding in file "src/loader/cmt.ml", line 444, characters 10-81
  Called from Odoc_loader__Cmt.read_structure_item in file "src/loader/cmt.ml", line 510, characters 14-47
  Called from Odoc_loader__Cmt.read_structure.(fun) in file "src/loader/cmt.ml", line 592, characters 24-61
  Called from Stdlib__List.fold_left in file "list.ml", line 121, characters 24-34
  Called from Odoc_loader__Cmt.read_structure in file "src/loader/cmt.ml", line 590, characters 4-127
  Called from Odoc_loader__Cmt.read_implementation in file "src/loader/cmt.ml", line 605, characters 4-79
  Called from Odoc_loader.read_cmt in file "src/loader/odoc_loader.ml", line 169, characters 34-74
  Called from Odoc_loader.wrap_errors.(fun) in file "src/loader/odoc_loader.ml", line 192, characters 10-14
  Called from Odoc_model__Error.catch in file "src/model/error.ml", line 54, characters 21-27
  Called from Odoc_model__Error.catch_warnings.(fun) in file "src/model/error.ml", line 89, characters 18-22
  Called from Odoc_model__Error.with_ref in file "src/model/error.ml", line 67, characters 12-16
  Re-raised at Odoc_model__Error.with_ref in file "src/model/error.ml", line 72, characters 4-11
  Called from Odoc_odoc__Compile.resolve_and_substitute in file "src/odoc/compile.ml", line 111, characters 8-72
  Called from Odoc_model__Error.catch in file "src/model/error.ml", line 54, characters 21-27
  Called from Odoc_model__Error.catch_warnings.(fun) in file "src/model/error.ml", line 89, characters 18-22
  Called from Odoc_model__Error.with_ref in file "src/model/error.ml", line 67, characters 12-16
  Re-raised at Odoc_model__Error.with_ref in file "src/model/error.ml", line 72, characters 4-11
  Called from Odoc_odoc__Compile.compile.(fun) in file "src/odoc/compile.ml", line 297, characters 6-180
  Called from Cmdliner_term.app.(fun) in file "cmdliner_term.ml", line 24, characters 19-24
  Called from Cmdliner_term.app.(fun) in file "cmdliner_term.ml", line 22, characters 12-19
  Called from Cmdliner_eval.run_parser in file "cmdliner_eval.ml", line 34, characters 37-44

Note that this error is raised by all odoc versions 2.4.* and 2.3., but not by odoc 2.2..

[jonludlam]

I wouldn't be surprised to find this is fixed by #1082. It might be worth trying the master branch to see if it still fails?

[NicNomadic]

I think it doesn't fix it. This what I tried, to be sure:

• cloned the odoc repo under ~/Tmp/odoc
• cd odoc
• make
• cd ../tezos
• ln -s ~/Tmp/odoc/_build/default/src/odoc/bin/main.exe _opam/bin/odoc
• odoc --version
  %%VERSION%%
• dune build @doc --stop-on-first-error
  odoc: internal error, uncaught exception:
  Not_found
  Raised at Ident.find_same in file "typing/ident.ml", line 253, characters 6-21

So, as I couldn't install the master version with opam, I added a symlink in my path to the binary built on master. Is this test conclusive?

[jonludlam]

conclusive enough :-) I'll take a look.

[NicNomadic]

I confirm that replaying the test above works fine using the odoc on latest master branch. Thanks a lot!

Do you have an idea about which future odoc release should contain this fix?