poky/documentation/migration-guides/migration-5.0.rst

.. SPDX-License-Identifier: CC-BY-SA-2.0-UK

Release 5.0 LTS (scarthgap)
===========================

Migration notes for 5.0 (scarthgap)
------------------------------------

This section provides migration information for moving to the Yocto
Project 5.0 Release (codename "scarthgap") from the prior release.

To migrate from an earlier LTS release, you **also** need to check all
the previous migration notes from your release to this new one:

-  :doc:`/migration-guides/migration-4.3`
-  :doc:`/migration-guides/migration-4.2`
-  :doc:`/migration-guides/migration-4.1`
-  :doc:`/migration-guides/migration-4.0`
-  :doc:`/migration-guides/migration-3.4`
-  :doc:`/migration-guides/migration-3.3`
-  :doc:`/migration-guides/migration-3.2`

.. _migration-5.0-supported-kernel-versions:

Supported kernel versions
~~~~~~~~~~~~~~~~~~~~~~~~~

The :term:`OLDEST_KERNEL` setting is still "5.15" in this release, meaning that
out the box, older kernels are not supported. See :ref:`4.3 migration notes
<migration-4.3-supported-kernel-versions>` for details.

.. _migration-5.0-supported-distributions:

Supported distributions
~~~~~~~~~~~~~~~~~~~~~~~

Compared to the previous releases, running BitBake is supported on new
GNU/Linux distributions:

-  Rocky 9

On the other hand, some earlier distributions are no longer supported:

-  Fedora 37
-  Ubuntu 22.10
-  OpenSUSE Leap 15.3

See :ref:`all supported distributions <system-requirements-supported-distros>`.

.. _migration-5.0-go-changes:

Go language changes
~~~~~~~~~~~~~~~~~~~

The ``linkmode`` flag was dropped from ``GO_LDFLAGS`` for ``nativesdk`` and
``cross-canadian``. Also, dynamic linking was disabled for the whole set of
(previously) supported architectures in the ``goarch`` class.

.. _migration-5.0-systemd-changes:

systemd changes
~~~~~~~~~~~~~~~

Systemd's nss-resolve plugin is now supported and can be added via the
``nss-resolve`` :term:`PACKAGECONFIG` option , which is from now on required
(along with ``resolved``) by the ``systemd-resolved`` feature. Related to that
(i.e., Systemd's network name resolution), an option to use ``stub-resolv.conf``
was added as well.

.. _migration-5.0-recipe-changes:

Recipe changes
~~~~~~~~~~~~~~

-  Runtime testing of ptest now fails if no test results are returned by
   any given ptest.

.. _migration-5.0-deprecated-variables:

Deprecated variables
~~~~~~~~~~~~~~~~~~~~

-  ``CVE_CHECK_IGNORE`` should be replaced with :term:`CVE_STATUS`


.. _migration-5.0-removed-variables:

Removed variables
~~~~~~~~~~~~~~~~~

The following variables have been removed:

-  ``DEPLOY_DIR_TAR``: no longer needed since the package_tar class was removed in 4.2.
-  ``PYTHON_PN``: Python 2 has previously been removed, leaving Python 3 as the sole
   major version. Therefore, this abstraction to differentiate both versions is
   no longer needed.
-  ``oldincludedir``
-  ``USE_L10N``: previously deprecated, and now removed.
-  ``CVE_SOCKET_TIMEOUT``
-  ``SERIAL_CONSOLES_CHECK`` - use :term:`SERIAL_CONSOLES` instead as all consoles specified in the latter are checked for their existence before a ``getty`` is started.

.. _migration-5.0-removed-recipes:

Removed recipes
~~~~~~~~~~~~~~~

The following recipes have been removed in this release:

-  ``libcroco``: deprecated and archived by the Gnome Project.
-  ``liberror-perl``: unmaintained and no longer needed - moved to meta-perl.
-  ``linux-yocto``: version 6.1 (version 6.6 provided instead).
-  ``systemtap-uprobes``: obsolete.
-  ``zvariant``: fails to build with newer Rust.

.. _migration-5.0-removed-classes:

Removed classes
~~~~~~~~~~~~~~~

No classes have been removed in this release.

.. _migration-5.0-qemu-changes:

QEMU changes
~~~~~~~~~~~~

In ``tune-core2``, the cpu models ``n270`` and ``core2duo`` are no longer
passed to QEMU, since its documentation recommends not using them with ``-cpu``
option. Therefore, from now on, ``Nehalem`` model is used instead.


ipk packaging changes
~~~~~~~~~~~~~~~~~~~~~

ipk packaging (using ``opkg``) now uses ``zstd`` compression instead of ``xz``
for better compression and performance. This does mean that ``.ipk`` packages
built using the 5.0 release requires Opkg built with zstd enabled --- naturally
this is the case in 5.0, but at least by default these packages will not be
usable on older systems where Opkg does not have zstd enabled at build time.

Additionally, the internal dependency solver in Opkg is now deprecated --- it
is still available in this release but will trigger a warning if selected.
The default has been the external ``libsolv`` solver for some time, but if you
have explicitly removed that from :term:`PACKAGECONFIG` for Opkg to
select the internal solver, you should plan to switch to ``libsolv`` in the
near future (by including ``libsolv`` your custom :term:`PACKAGECONFIG` value
for Opkg, or reverting to the default value).


motd message when using ``DISTRO = "poky"``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The default ``poky`` :term:`DISTRO` is explicitly a *reference* distribution
for testing and development purposes.  It enables most hardware and software
features so that they can be tested, but this also means that
from a security point of view the attack surface is very large.

We encourage anyone using the Yocto Project for production use to create
their own distribution and not use Poky. To encourage this behaviour
further, in 5.0 a warning has been added to ``/etc/motd`` when Poky is used
so that the developer will see it when they log in. If you are creating your
own distribution this message will not show up.

For information on how to create your own distribution, see
":ref:`dev-manual/custom-distribution:creating your own distribution`".

.. _migration-5.0-misc-changes:

Miscellaneous changes
~~~~~~~~~~~~~~~~~~~~~

-  ``bitbake-whatchanged`` script was removed as it was broken and unmaintained.

-  ``scripts/sstate-cache-management.sh`` has been replaced by
   ``scripts/sstate-cache-management.py``, a more performant Python-based version.

-  The ``bmap-tools`` recipe has been renamed to ``bmaptool``.

-  ``gpgme`` has had Python binding support disabled since upstream does not
   support Python 3.12 yet. This will be fixed in future once it is fixed upstream.)

-  A warning will now be shown if the ``virtual/`` prefix is used in runtime
   contexts (:term:`RDEPENDS` / :term:`RPROVIDES`) ---
   See :ref:`virtual-slash <qa-check-virtual-slash>` for details.

-  ``recipetool`` now prefixes the names of recipes created for Python modules
   with ``python3-``.

-  The :ref:`ref-classes-cve-check` class no longer produces a warning for
   remote patches --- it only logs a note and does not try to fetch the patch
   in order to scan it for issues or CVE numbers. However, CVE number
   references in remote patch file names will now be picked up.

-  The values of :term:`PE` and :term:`PR` have been dropped from
   ``-f{file,macro,debug}-prefix-map``, in order to avoid unnecessary churn
   in debugging symbol paths when the version is bumped. This is unlikely to
   cause issues, but if you are paying attention to the debugging source path
   (e.g. in recipes that need to manipulate these files during packaging) then
   you will notice the difference. A new :term:`TARGET_DBGSRC_DIR` variable is
   provided to make this easier.

-  ``ccache`` no longer supports FORTRAN.