3.22.0 release tracker

[shonfeder]

Known blockers

• Update code error message to stop mentioning _build/log #13679 because it could lead to user confusion if they encounter bugs that they need to report.
• fix: diff action missing files #13696
• Print diffs on patch back source tree diff failures #13697
• dune rpc: handle errors from server requests #13709
• portable lock directories don't filter depexts in the same manner #13699
  • fix(pkg): filter unknown variables in depexts #13729
• Fix dependency bounds for dune-action-trace #13730
• dune-action-trace packaging is misconfigured #13732
  • chore: skip install tests for dune-action-trace #13736
• Place default trace file in the build directory #13735
• regression in dune lang 1.0 semantics of cxx_ fields due to changes in select semantics #13802
• Add upper bound on dune-rpc at 3.22 opam-repository#29555
• Add upper bound on stdune 3.22 opam-repository#29561

Release

• Update dune changelog to 3.22.0 on 3.22.0-rc branch [link to dune PR]
• Run mirage tests: https://github.com/ocaml/dune/actions/runs/22589371741/job/65442926531
• Triage (ensure it does not break anything) via draft opam-repo PRs of alpha releases
  • [new release] dune (18 packages) (3.22.0~alpha0) opam-repository#29497
  • [new release] dune (18 packages) (3.22.0~alpha1) opam-repository#29535
  • [new release] dune (18 packages) (3.22.0~alpha2) opam-repository#29547
• Open pull request on opam-repository
  • [new release] dune (18 packages) (3.22.0) opam-repository#29562

Post-release

• Merge release branch into main
• Write a post about the release on Discuss: https://discuss.ocaml.org/t/ann-dune-3-22/17912
• Update on ocaml.org: Announce release of dune 3.22 ocaml.org#3570
• Store the revdeps error file in the logs

[avsm]

There seems to have been a regression in 3.21 here that's resulted in an upper bound (always dangerous with dune) https://tangled.org/futur.blue/pegasus/commit/e1813c251ec39742bca961aaa96d501a8279170f -- I've not looked further though.

[Alizter]

@avsm I can confirm that Dune 3.20 can lock and build correctly whereas 3.21 is locking slightly differently causing the build to fail. As long as you don't update your lock file with 3.21, this shouldn't count as a regression as both versions of dune will be able to build with it. Therefore a fix for this issue does not need to be backported to 3.21. However in 3.22 we should fix it. I will open an issue and a reproduction case when I've understood the problem a bit better. For now, I would recommend lifting the dune version constraints in that repo.

[shonfeder]

There are packaging regressions turned up by ocaml CI. I'm working on fixes there currently.

dune-action-trace.3.22.0~alpha0

lower-bounds (failed: Unbound type constructor Csexp.t)
tests (failed: Library "stdune" not found.)

And on ocaml 4.11 and earlier:

#=== ERROR while compiling dune-action-trace.3.22.0~alpha0 ====================#
# context              2.5.0 | linux/x86_64 | ocaml-base-compiler.4.08.1 | pinned(https://github.com/ocaml/dune/releases/download/3.22.0_alpha0/dune-3.22.0.alpha0.tbz)
# path                 ~/.opam/4.08/.opam-switch/build/dune-action-trace.3.22.0~alpha0
# command              ~/.opam/opam-init/hooks/sandbox.sh build dune build -p dune-action-trace -j 71 @install
# exit-code            1
# env-file             ~/.opam/log/dune-action-trace-7-1fc7f7.env
# output-file          ~/.opam/log/dune-action-trace-7-1fc7f7.out
### output ###
# (cd _build/default && /home/opam/.opam/4.08/bin/ocamlc.opt -w @1..3@5..28@31..39@43@46..47@49..57@61..62@67@69-40 -strict-sequence -strict-formats -alert -unstable -g -bin-annot -I otherlibs/dune-action-trace/.dune_action_trace.objs/byte -I /home/opam/.opam/4.08/lib/csexp -intf-suffix .ml -no-alias-deps -o otherlibs/dune-action-trace/.dune_action_trace.objs/byte/dune_action_trace.cmo -c -impl otherlibs/dune-action-trace/dune_action_trace.ml)
# File "otherlibs/dune-action-trace/dune_action_trace.ml", line 56, characters 29-34:
# 56 |          match Sys.mkdir dir 0o777 with
#                                   ^^^^^
# Error (warning 20): this argument will not be used by the function.
# (cd _build/default && /home/opam/.opam/4.08/bin/ocamlopt.opt -w @1..3@5..28@31..39@43@46..47@49..57@61..62@67@69-40 -strict-sequence -strict-formats -alert -unstable -g -I otherlibs/dune-action-trace/.dune_action_trace.objs/byte -I otherlibs/dune-action-trace/.dune_action_trace.objs/native -I /home/opam/.opam/4.08/lib/csexp -intf-suffix .ml -no-alias-deps -o otherlibs/dune-action-trace/.dune_action_trace.objs/native/dune_action_trace.cmx -c -impl otherlibs/dune-action-trace/dune_action_trace.ml)
# File "otherlibs/dune-action-trace/dune_action_trace.ml", line 56, characters 29-34:
# 56 |          match Sys.mkdir dir 0o777 with
#                                   ^^^^^
# Error (warning 20): this argument will not be used by the function.

[Alizter]

@shonfeder You can change the lower bound for OCaml on dune-action-trace to 4.12 (the version where Sys.mkdir with these arguments was introduced). This should be done in the dune-project.