opam switch create . 5.2.0 isn't working on m2 mac

[feihong]

$ opam config report
# opam config report
# opam-version         2.1.6
# self-upgrade         no
# system               arch=arm64 os=macos os-distribution=homebrew os-version=14.4
# solver               builtin-mccs+glpk
# install-criteria     -removed,-count[avoid-version,changed],-count[version-lag,request],-count[version-lag,changed],-count[missing-depexts,changed],-changed
# upgrade-criteria     -removed,-count[avoid-version,changed],-count[version-lag,solution],-count[missing-depexts,changed],-new
# jobs                 7
# repositories         1 (http) (default repo at 402ab79d)
# pinned               0
# current-switch       default
# ocaml:native         true
# ocaml:native-tools   true
# ocaml:native-dynlink true
# ocaml:stubsdir       /Users/fhsu/.opam/default/lib/ocaml/stublibs:/Users/fhsu/.opam/default/lib/ocaml
# ocaml:preinstalled   false
# ocaml:compiler       5.0.0

I checked out the main branch of [melange-for-react-devs-template](https://github.com/melange-re/melange-for-react-devs-template} and then ran:

 $ opam switch create . 5.2.0 -y --deps-only

<><> Installing new switch packages <><><><><><><><><><><><><><><><><><><><>  🐫
Switch invariant: ["ocaml-base-compiler" {= "5.2.0"} | "ocaml-system" {= "5.2.0"}]
The following actions will be performed:
  ∗ install ocaml-options-vanilla 1
  ∗ install host-arch-arm64       1
  ∗ install base-bigarray         base
  ∗ install base-threads          base
  ∗ install ocaml-base-compiler   5.2.0
  ∗ install host-system-other     1
  ∗ install base-unix             base
  ∗ install ocaml-config          3
  ∗ install ocaml                 5.2.0
  ∗ install ocamlfind             1.9.6
  ∗ install dune                  3.15.3
  ∗ install cmdliner              1.3.0
  ∗ install base-domains          base
  ∗ install stdlib-shims          0.3.0
  ∗ install sexplib0              v0.17.0
  ∗ install ppx_derivers          1.2.1
  ∗ install ocaml-compiler-libs   v0.17.0
  ∗ install menhirSdk             20231231
  ∗ install menhirLib             20231231
  ∗ install menhirCST             20231231
  ∗ install fix                   20230505
  ∗ install dune-build-info       3.15.3
  ∗ install cppo                  1.6.9
  ∗ install base-nnp              base
  ∗ install ppxlib                0.32.1
  ∗ install menhir                20231231
  ∗ install merlin-extend         0.6.1
  ∗ install melange               4.0.0-52
  ∗ install reason                3.11.0
  ∗ install reason-react-ppx      0.14.1
  ∗ install reason-react          0.14.1
===== ∗ 31 =====

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><>  🐫
∗ installed base-bigarray.base
∗ installed base-threads.base
∗ installed base-unix.base
⬇ retrieved dune.3.15.3  (cached)
⬇ retrieved cppo.1.6.9  (cached)
⬇ retrieved cmdliner.1.3.0  (cached)
∗ installed host-arch-arm64.1
∗ installed host-system-other.1
⬇ retrieved fix.20230505  (cached)
⬇ retrieved menhir.20231231  (cached)
⬇ retrieved menhirCST.20231231  (cached)
⬇ retrieved menhirLib.20231231  (cached)
⬇ retrieved melange.4.0.0-52  (cached)
⬇ retrieved menhirSdk.20231231  (cached)
⬇ retrieved merlin-extend.0.6.1  (cached)
⬇ retrieved dune-build-info.3.15.3  (cached)
⬇ retrieved ocaml-config.3  (cached)
∗ installed ocaml-options-vanilla.1
⬇ retrieved ocaml-compiler-libs.v0.17.0  (cached)
⬇ retrieved ocaml-base-compiler.5.2.0  (cached)
⬇ retrieved ppxlib.0.32.1  (cached)
⬇ retrieved ppx_derivers.1.2.1  (cached)
⬇ retrieved ocamlfind.1.9.6  (cached)
⬇ retrieved reason.3.11.0  (cached)
⬇ retrieved reason-react-ppx.0.14.1  (cached)
⬇ retrieved sexplib0.v0.17.0  (cached)
⬇ retrieved stdlib-shims.0.3.0  (cached)
⬇ retrieved reason-react.0.14.1  (cached)
∗ installed ocaml-base-compiler.5.2.0
∗ installed ocaml-config.3
[ERROR] The compilation of ocaml.5.2.0 failed at "ocaml
        /Users/fhsu/work/melange-for-react-devs-template/_opam/share/ocaml-config/gen_ocaml_config.ml 5.2.0
        ocaml".

#=== ERROR while compiling ocaml.5.2.0 ========================================#
# context     2.1.6 | macos/arm64 | ocaml-base-compiler.5.2.0 | https://opam.ocaml.org#402ab79d
# path        ~/work/melange-for-react-devs-template/_opam/.opam-switch/build/ocaml.5.2.0
# command     ~/.opam/opam-init/hooks/sandbox.sh build ocaml /Users/fhsu/work/melange-for-react-devs-template/_opam/share/ocaml-config/gen_ocaml_config.ml 5.2.0 ocaml
# exit-code   2
# env-file    ~/.opam/log/ocaml-83931-dad3d7.env
# output-file ~/.opam/log/ocaml-83931-dad3d7.out
### output ###
# Cannot find file /Users/fhsu/work/melange-for-react-devs-template/_opam/share/ocaml-config/gen_ocaml_config.ml.



<><> Error report <><><><><><><><><><><><><><><><><><><><><><><><><><><><><>  🐫
┌─ The following actions failed
│ λ build ocaml 5.2.0
└─
┌─ The following changes have been performed (the rest was aborted)
│ ∗ install base-bigarray         base
│ ∗ install base-threads          base
│ ∗ install base-unix             base
│ ∗ install host-arch-arm64       1
│ ∗ install host-system-other     1
│ ∗ install ocaml-base-compiler   5.2.0
│ ∗ install ocaml-config          3
│ ∗ install ocaml-options-vanilla 1
└─
Switch initialisation failed: clean up? ('n' will leave the switch partially installed) [Y/n] y

[hannesm]

Thanks for your report, this seems to be caused by recent removals of files from opam-repository.

To recover from your situation, rm -rf ~/.opam/repo/default{,.tar.gz} && opam update default should help in the short-term. In the medium-term, please ensure to have GNU patch installed (via macports or homebrew).

This is further discussed at https://discuss.ocaml.org/t/the-compilation-of-ocaml-5-1-1-failed-at-ocaml-gen-ocaml-config-ml-5-1-1-ocaml/14731 and also #25961 #26050

[kit-ty-kate]

Duplicated of #25961