[coq] Composition with (boot) theories hangs with a cycle in Dune > 3.7 when coq lang > 0.6

[ejgallego]

I've discovered some issues when testing composition with Coq itself in Dune 3.8.

First issue is as follows, given:

• a composed Coq build (see [1] how to setup)
• a (lang coq 0.7) or 0.8

Then Dune will fail with:

Error: Dependency cycle between:  
   Computing installable artifacts for package coqide-server
-> required by Computing installable artifacts for package coq-core
-> required by _build/default/coq-core.install
-> required by alias default in dune:22

This seems to be related to the Coq_config resolution in boot. Note that the issue doesn't occur for lower versions of the Coq language.

cc @Alizter

[1] To reproduce, you can use Coq's main branch:

$ git clone https://github.com/coq/coq.git
$ cd coq && cp theories/dune.disabled theories/dune
$ # edit dune-project to raise `(lang coq ...)`
$ dune build @default

[ejgallego]

@rgrinberg it seems to the that the problem here is as follows:

• we have two packages coq-core and coq-stdlib, coqc is in coq-core, coq-stdlib has all the .v files
• to compute the list of files to install for coq-stdlib, Dune needs to call coqc --config to see if Coq has native compiler enabled
• the resolution of coqc in this case seems to depend on all the .install files in scope.

And boom! Here we got a cycle. Is there any hope to avoid this?

It would also be fine for us to use a weaker resolution method.

[rgrinberg]

Can you post the trace of the cycle?

EDIT: I see the cycle is in the first post.

I suppose we can change the computation of the artifacts db to do binaries and libraries separately.

[ejgallego]

I suppose we can change the computation of the artifacts db to do binaries and libraries separately.

Happy to follow your lead on this.

For a short-term fix, do we have a method that will resolve the binary more weakly ?

[Alizter]

Well there is Bin.which but that won't be able to find it from a super_context.

[ejgallego]

If that doesn't trigger the cycle we could live with it, no?

The only downside is that the Coq composed build wouldn't detect native or version, but that's not a big deal I think.

[ejgallego]

I am surprised tho the cycle doesn't trigger even in a non-composed scenario wil multiple packages tho.

We may likely have a problem there too, but maybe people haven't bumped the (lang coq ) variable yet so it is not bitting them.

[rgrinberg]

Could you prepare a small test case (with a fake coq package)? I'll have a look.

[Alizter]

I tried to prepare a case but I ended up creating a loop that hangs. Which is independently a strange occurrence.

Testing memo cycle in dune coq rules

  $ cat > dune-project << EOF
  > (lang dune 3.9)
  > (using coq 0.8)
  > (package (name foo))
  > (package (name bar))
  > EOF

  $ cat > dune << EOF
  > (executable
  >  (public_name coqc)
  >  (package foo))
  > 
  > (coq.theory
  >  (name bar)
  >  (package bar))
  > EOF

  $ cat > coqc.ml
  $ cat > bar.v

  $ dune build @install

[ejgallego]

Note that in my original case dune also hanged, but it did print the cycle information before getting stuck.

[rgrinberg]

Yeah those are separate issues.

One is a bug with dune's cycle detection. The other is a true cycle in our rules that we need to workaround.

Let's try to get a reproduction case of the latter.

[ejgallego]

@Alizter case works as a reproduction case for the rule cycles, even with just a single package.

The surprising thing is that if you rename the public name from coqc to some other name, the cycle disappears.

[ejgallego]

I'm afraid I'm stuck on how to make progress on this; it is unfortunate as I cannot migrate a few project to (lang coq 0.8) which I need in order to fix the remaining TODOs towards 1.0.

[Alizter]

I started printing dep nodes that are being added in the first second of dune running in my example and got this:

Details

  ("fs_memo_for_watching_via_parent", In_source_tree "dune-workspace")
  ("fs_memo_for_watching_directly", In_source_tree ".")
  ("fs_memo_for_watching_via_parent", In_source_tree ".bin")
  ("fs_memo_for_watching_directly", In_source_tree ".bin")
  ("readdir-of-source-path", In_source_tree ".")
  ("fs_memo_for_watching_via_parent", In_source_tree "dune-project")
  ("fs_memo_for_watching_via_parent", In_source_tree ".");
  ("fs_memo_for_watching_directly", In_source_tree ".")
  ("fs_memo_for_watching_via_parent", In_source_tree "dune-project")
  ("ensure-dune-project-file-exists",
  (false,
  { name = Named "foo"
  ; root = In_source_tree "."
  ; version = None
  ; dune_version = (3, 9)
  ; info =
      { source = None
      ; license = None
      ; homepage = None
      ; documentation = None
      ; bug_reports = None
      ; maintainers = None
      ; authors = None
      }
  ; project_file = In_source_tree "dune-project"
  ; packages =
      [ ("foo",
        { id = { name = "foo"; dir = In_source_tree "." }
        ; synopsis = None
        ; description = None
        ; depends = []
        ; conflicts = []
        ; depopts = []
        ; info =
            { source = None
            ; license = None
            ; homepage = None
            ; documentation = None
            ; bug_reports = None
            ; maintainers = None
            ; authors = None
            }
        ; has_opam_file = Exists false
        ; tags = []
        ; version = None
        ; deprecated_package_names = map {}
        ; sites = map {}
        ; allow_empty = false
        })
      ]
  ; implicit_transitive_deps = true
  ; wrapped_executables = true
  ; map_workspace_root = true
  ; executables_implicit_empty_intf = true
  ; accept_alternative_dune_file_name = false
  ; generate_opam_files = false
  ; warnings = <opaque>
  ; use_standard_c_and_cxx_flags = Some true
  ; file_key = "3c4086b92437"
  ; dialects =
      map
        { "ocaml" :
            { name = "ocaml"
            ; file_kinds =
                { impl =
                    Some
                      { kind = "impl"
                      ; extension = ".ml"
                      ; preprocess = None
                      ; format =
                          Some
                            ([ "chdir"
                             ; template "%{workspace_root}"
                             ; [ "run"
                               ; "ocamlformat"
                               ; "--impl"
                               ; template "%{input_file}"
                               ]
                             ],
                            [ ".ocamlformat"
                            ; ".ocamlformat-ignore"
                            ; ".ocamlformat-enable"
                            ])
                      }
                ; intf =
                    Some
                      { kind = "intf"
                      ; extension = ".mli"
                      ; preprocess = None
                      ; format =
                          Some
                            ([ "chdir"
                             ; template "%{workspace_root}"
                             ; [ "run"
                               ; "ocamlformat"
                               ; "--intf"
                               ; template "%{input_file}"
                               ]
                             ],
                            [ ".ocamlformat"
                            ; ".ocamlformat-ignore"
                            ; ".ocamlformat-enable"
                            ])
                      }
                }
            }
        ; "reason" :
            { name = "reason"
            ; file_kinds =
                { impl =
                    Some
                      { kind = "impl"
                      ; extension = ".re"
                      ; preprocess =
                          Some
                            [ "run"
                            ; "refmt"
                            ; "--print"
                            ; "binary"
                            ; template "%{input_file}"
                            ]
                      ; format =
                          Some
                            ([ "run"; "refmt"; template "%{input_file}" ], [])
                      }
                ; intf =
                    Some
                      { kind = "intf"
                      ; extension = ".rei"
                      ; preprocess =
                          Some
                            [ "run"
                            ; "refmt"
                            ; "--print"
                            ; "binary"
                            ; template "%{input_file}"
                            ]
                      ; format =
                          Some
                            ([ "run"; "refmt"; template "%{input_file}" ], [])
                      }
                }
            }
        }
  ; explicit_js_mode = true
  ; format_config = None
  ; subst_config = None
  ; strict_package_deps = false
  ; cram = true
  ; allow_approximate_merlin = <opaque>
  ; expand_aliases_in_sandbox = false
  ; opam_file_location = Relative_to_project
  }))
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  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/2z3arz5ni43qdkbk95pmkl25kf77ww3i-glib-2.76.4-bin/bin/ocamlc")
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  ("fs_memo_for_watching_via_parent",
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  ("which", <opaque>)
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  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/bin/ocamlopt.opt")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/bin/ocaml")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/bin/ocamldep.opt")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/bin/ocamlmklib.opt")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/bin/ocamlobjinfo.opt")
  ("ocaml_and_build_env_kind", ())
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  ("default_ocamlpath", ())
  ("build-contexts", ())
  ("context-db-get", "default")
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  ("build-contexts", ())
  ("findlib", ())
  ("default_ocamlpath", ())
  ("findlib_paths", ())
  ("ocaml_and_build_env_kind", ())
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/lib/ocaml/bigarray.cma")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/lib/ocaml/graphics.cma")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/l1vs77vaaby67lfbnribaimqzpd19bci-ocaml-4.14.1/lib/ocaml/nums.cma")
  ("findlib", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("build-contexts", ())
  ("Artifacts_db.all", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("Artifacts_db.all", ())
  ("make_sctx", ())
  ("Super_context.all", ())
  ("Super_context.all", ())
  ("filtered_stanzas", ())
  ("only_packages", ())
  ("dune_load", ())
  ("get_installed_binaries", ())
  ("<unnamed>", ())
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("find-dir-raw", In_source_tree ".")
  ("Dune_files.interpret", <opaque>)
  ("only_packages", ())
  ("ocaml_and_build_env_kind", ())
  ("env-nodes-memo", In_build_dir "default")
  ("env-nodes-memo", In_build_dir "default")
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("default_env", ())
  ("<unnamed>", ())
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("workspace", ())
  ("<unnamed>", ())
  ("Build_config.set", ())
  ("find-dir-raw", In_source_tree ".")
  ("workspace", ())
  ("find-dir-raw", In_source_tree ".")
  ("Dune_files.interpret", <opaque>)
  ("only_packages", ())
  ("get-dir-status", In_build_dir "default")
  ("find-dir-raw", In_source_tree ".")
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("fs_memo_for_watching_via_parent",
  External
    "/home/ali/dune/_build/default/test/blackbox-tests/test-cases/.bin/coqc")
  ("fs_memo_for_watching_via_parent",
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  ("fs_memo_for_watching_via_parent",
  External
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    "/nix/store/znqwpxy9jlxcgi2ms2hga0ch87bbbr9g-patchelf-0.15.0/bin/coqc")
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  External
    "/nix/store/0glncgfnkf522k56kvmbw0524zqc2ai9-ocaml4.14.1-js_of_ocaml-compiler-5.4.0/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/d9911dza8lpz5rdghaq599hfx530yjwn-ocaml4.14.1-yojson-2.1.1/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/lw6p4issadazgak0lhv5jmkn24c2q26n-ocaml4.14.1-utop-2.13.1/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/r6b2zl1zqr100ki5x6bbnpykj4rh6dc1-ocaml4.14.1-lambda-term-3.3.1/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/nm2b6r5fv634w5iygxrm6xjj0wg3776y-ocaml4.14.1-uutf-1.0.3/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/njnkwi1inzih1m9gq6zh4aqf0h6d3ygq-ocaml4.14.1-uuseg-15.0.0/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/vwkvhj69z4qqgmpa2lwm97kabf12p26r-coreutils-9.3/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/qyzfglbrqb5ck0dgljplin2bvc4995w7-findutils-4.9.0/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/x6y2i213maj6ibcn0qzgg7graif5qcvi-diffutils-3.10/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/g5p3ky90xa05ggg5szyb0pbbl2vp7n03-gnused-4.9/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/p2r51wfg9m3ga7pp7avslpfhfa7w5y83-gnugrep-3.11/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/cmn958i8qym0qvmvydl23fh3bm3fbhl7-gawk-5.2.2/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/f5qy259g9b4qh0hwz22z5j5bq3m53cpv-gnutar-1.35/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/kmr52zpw7wazxywqvzgpdx0vnn9prd3v-gzip-1.13/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External
    "/nix/store/w1mar48lwkavwy64mvj567lwaqnm2l11-bzip2-1.0.8-bin/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/9dh2csn531by6b1vr9jv85v4k17xwkid-gnumake-4.4.1/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/lf0wpjrj8yx4gsmw2s3xfl58ixmqk8qa-bash-5.2-p15/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/pinwlz7294p37d2sbkdpjildzxii42vv-patch-2.7.6/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/skrzk0g88jf9rg28labqsyxv7gg357q1-xz-5.4.4-bin/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/store/h5pshzq92r2xcv6w1p10cmkar4nyv0xp-file-5.45/bin/coqc")
  ("fs_memo_for_watching_via_parent", External "/run/wrappers/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/home/ali/.nix-profile/bin/coqc")
  ("fs_memo_for_watching_via_parent", External "/nix/profile/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/home/ali/.local/state/nix/profile/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/etc/profiles/per-user/ali/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/nix/var/nix/profiles/default/bin/coqc")
  ("fs_memo_for_watching_via_parent",
  External "/run/current-system/sw/bin/coqc")
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("which", <opaque>)
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("find-dir-raw", In_source_tree ".")
  ("Dune_files.interpret", <opaque>)
  ("only_packages", ())
  ("gen-rules", In_build_dir "default")
  ("Super_context.all", ())
  ("Super_context.all", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("filtered_stanzas", ())
  ("only_packages", ())
  ("dune_load", ())
  ("lib-entries-map", <opaque>)
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("filtered_stanzas", ())
  ("only_packages", ())
  ("dune_load", ())
  ("lib-entries-map", <opaque>)
  ("only_packages", ())
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("dune_load", ())
  ("only_packages", ())
  ("only_packages", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("filtered_stanzas", ())
  ("only_packages", ())
  ("dune_load", ())
  ("lib-entries-map", <opaque>)
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("filtered_stanzas", ())
  ("only_packages", ())
  ("dune_load", ())
  ("lib-entries-map", <opaque>)
  ("only_packages", ())
  ("Super_context.all", ())
  ("get-dir-status", In_build_dir "default")
  ("dir-contents-get0", ("default", In_build_dir "default"))
  ("build-contexts", ())
  ("Build_config.set", ())
  ("gen-rules", In_build_dir "default")
  ("gen-rules", In_build_dir "default/.dune")
  ("<unnamed>", ())
  ("find-dir-raw", In_source_tree ".")
  ("find-dir-raw", In_source_tree ".dune")
  ("find-dir-raw", In_source_tree ".dune")
  ("load-dir", In_build_dir "default/.dune")
  ("find-dir-raw", In_source_tree ".")
  ("workspace", ())
  ("execution-parameters-of-dir", In_build_dir "default/.dune")
  ("context-db-get", "default")
  ("ocaml_and_build_env_kind", ())
  ("Rule.make", ())
  ("execute-rule", { id = 3; info = Internal })
  ("<unnamed>", ())
  ("build-file", In_build_dir "default/.dune/configurator")
  ("load-dir", In_build_dir "default/.dune")
  ("execution-parameters-of-dir", In_build_dir "default/.dune")
  ("context-db-get", "default")
  ("ocaml_and_build_env_kind", ())
  ("Rule.make", ())
  ("execute-rule", { id = 4; info = Internal })
  ("<unnamed>", ())
  ("build-file", In_build_dir "default/.dune/configurator.v2")
  ("force-configuration-files", ())
  ("env-nodes-memo", In_build_dir "default")
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("find-dir-raw", In_source_tree ".")
  ("Dune_files.interpret", <opaque>)
  ("only_packages", ())
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("find-dir-raw", In_source_tree ".")
  ("<unnamed>", ())
  ("ocaml_and_build_env_kind", ())
  ("ocaml_and_build_env_kind", ())
  ("env-nodes-memo", In_build_dir "default")
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("find-dir-raw", In_source_tree ".")
  ("ocaml_and_build_env_kind", ())
  ("ocaml_and_build_env_kind", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("context-db-get", "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("<unnamed>", ())
  ("Artifacts.Bin.add_binaries", ())
  ("Artifacts.Bin.add_binaries", ())
  ("Artifacts.Bin.add_binaries", ())
  ("Build_config.set", ())
  ("workspace", ())
  ("gen-rules", In_build_dir "install")
  ("Super_context.all", ())
  ("dune_load", ())
  ("only_packages", ())
  ("install-rules-and-pkg-entries",
  ("default",
  { id = { name = "foo"; dir = In_source_tree "." }
  ; synopsis = None
  ; description = None
  ; depends = []
  ; conflicts = []
  ; depopts = []
  ; info =
      { source = None
      ; license = None
      ; homepage = None
      ; documentation = None
      ; bug_reports = None
      ; maintainers = None
      ; authors = None
      }
  ; has_opam_file = Exists false
  ; tags = []
  ; version = None
  ; deprecated_package_names = map {}
  ; sites = map {}
  ; allow_empty = false
  }))
  ("install-rule-scheme", "default")
  ("restrict-by-child-non-default-outer", ())
  ("filtered_stanzas", ())
  ("only_packages", ())
  ("dune_load", ())
  ("dune_load", ())
  ("only_packages", ())
  ("find-dir-raw", In_source_tree ".")
  ("env-nodes-memo", In_build_dir "default")
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("env-nodes-memo", In_build_dir "default")
  ("<unnamed>", ())
  ("Artifacts.Bin.add_binaries", ())
  [130]

I haven't looked at it in full detail yet but there seems to be a lot of stuff I don't understand. which appears way more then I think it should and env-nodes also appears too many times.

[Alizter]

Why for example, is coqc being depended on in every path in PATH? That seems like a bug.

It seems that PATH=foo:bar:baz adds memo nodes for foo/coqc, bar/coqc and baz/coqc.

[ejgallego]

Tested a bit more with gdb, but didn't make any progress. dune just deadlocks on the example.

[ejgallego]

Unsure why this wasn't closed by #9496 merge, doing it myself. Thanks Rudi !!