First release candidate for OCaml 5.4.0

Dear OCaml users,

The release of OCaml 5.4.0 is imminent.

As a final step, we are publishing a release candidate to check one last 
time
that everything is in order before the release in the upcoming week.

If you find any bugs, please report them on the OCaml's issue
tracker (https://github.com/ocaml/ocaml/issues).

Compared to the second beta, this release candidate contains a fix in 
the TSAN mode,
and one metadata fix in the change log. The full change log for OCaml 
5.4.0 is available on
GitHub(https://github.com/ocaml/ocaml/blob/5.4/Changes).

Happy hacking,
Florian Angeletti for the OCaml team.

Installation instructions
--------------------------------

The base compiler can be installed as an opam switch with the following 
commands on opam 2.1 and later:

     opam update
     opam switch create 5.4.0~rc1

The source code for the release candidate is also directly available on:

* GitHub: https://github.com/ocaml/ocaml/archive/5.4.0-rc1.tar.gz
* OCaml archives at Inria: 
https://caml.inria.fr/pub/distrib/ocaml-5.4/ocaml-5.4.0~rc1.tar.gz

Fine-tuned compiler configuration
---------------------------------------------

If you want to tweak the configuration of the compiler, you can switch 
to the option variant with:

     opam update
     opam switch create <switch_name> ocaml-variants.5.4.0~rc1+options 
<option_list>

where `<option_list>` is a space-separated list of `ocaml-option-*` 
packages. For instance, for a `flambda` and `no-flat-float-array` switch:

      opam switch create 5.4.0~rc1+flambda+nffa 
ocaml-variants.5.4.0~rc1+options ocaml-option-flambda 
ocaml-option-no-flat-float-array


All available options can be listed with `opam search ocaml-option`.