OCaml 4.08.1 RC1

Dear OCaml users,

The release of OCaml version 4.08.1 is imminent.
This new bugfix release fixes some compilation failures in presence of “-pack”,
and some native-code alignment issues on ARM64, PPC64 and amd64.
We have created a release candidate that you can test.

The source code is available at these addresses:


The compiler can also be installed as an OPAM switch with one of the
following commands:

opam switch create ocaml-variants.4.08.1+rc1 --repositories=default,ocaml-beta=git+https://github.com/ocaml/ocaml-beta-repository.git


opam switch create ocaml-variants.4.08.1+rc1+<VARIANT> --repositories=default,ocaml-beta=git+https://github.com/ocaml/ocaml-beta-repository.git

where you replace with one of these:

  • afl
  • default-unsafe-string
  • force-safe-string
  • flambda
  • fp
  • fp+flambda

We want to know about all bugs. Please report them here:

Happy hacking,
— Florian Angeletti for the OCaml team.

OCaml 4.08.1 changes:

Bug fixes:

  • #7887: ensure frame table is 8-aligned on ARM64 and PPC64
    (Xavier Leroy, report by Mark Hayden, review by Mark Shinwell
    and Gabriel Scherer)

  • #8751: fix bug that could result in misaligned data section when compiling to
    native-code on amd64. (observed with the mingw64 compiler)
    (Nicolás Ojeda Bär, review by David Allsopp)

  • #8769, #8770: Fix assertion failure with -pack
    (Leo White, review by Gabriel Scherer, report by Fabian @copy)


Are all the documentation fixes also included? I remember there were a bunch of minor issues with the manual.

The manual was fixed few days ago (the svg arrows are back too).

1 Like

Most, if not all, of the docs fixes have been cherry-picked to 4.08, yes - check https://github.com/ocaml/ocaml/commits/4.08/ if there are specific ones you were thinking of (although GitHub doesn’t show the 4.08.0 tag, you can clearly see the commit on 13 June for the version bump, so it’s less than a page of history)

1 Like

We released today a second release candidate to integrate a fix for dynlinking failures in bytecode mode that was affecting Frama-C .