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[<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
<chapter id='migration'>
<title>Migrating to a Newer Yocto Project Release</title>
<para>
This chapter provides information you can use to migrate work to a
newer Yocto Project release. You can find the same information in the
release notes for a given release.
</para>
<section id='general-migration-considerations'>
<title>General Migration Considerations</title>
<para>
Some considerations are not tied to a specific Yocto Project
release.
This section presents information you should consider when
migrating to any new Yocto Project release.
<itemizedlist>
<listitem><para><emphasis>Dealing with Customized Recipes</emphasis>:
Issues could arise if you take older recipes that contain
customizations and simply copy them forward expecting them
to work after you migrate to new Yocto Project metadata.
For example, suppose you have a recipe in your layer that is
a customized version of a core recipe copied from the earlier
release, rather than through the use of an append file.
When you migrate to a newer version of Yocto Project, the
metadata (e.g. perhaps an include file used by the recipe)
could have changed in a way that would break the build.
Say, for example, a function is removed from an include file
and the customized recipe tries to call that function.
</para>
<para>You could "forward-port" all your customizations in your
recipe so that everything works for the new release.
However, this is not the optimal solution as you would have
to repeat this process with each new release if changes
occur that give rise to problems.</para>
<para>The better solution (where practical) is to use append
files (<filename>*.bbappend</filename>) to capture any
customizations you want to make to a recipe.
Doing so, isolates your changes from the main recipe making
them much more manageable.
However, sometimes it is not practical to use an append
file.
A good example of this is when introducing a newer or older
version of a recipe in another layer.</para>
</listitem>
<listitem><para><emphasis>Updating Append Files</emphasis>:
Since append files generally only contain your customizations,
they often do not need to be adjusted for new releases.
However, if the <filename>.bbappend</filename> file is
specific to a particular version of the recipe (i.e. its
name does not use the % wildcard) and the version of the
recipe to which it is appending has changed, then you will
at a minimum need to rename the append file to match the
name of the recipe file.
A mismatch between an append file and its corresponding
recipe file (<filename>.bb</filename>) will
trigger an error during parsing.</para>
<para>Depending on the type of customization the append file
applies, other incompatibilities might occur when you
upgrade.
For example, if your append file applies a patch and the
recipe to which it is appending is updated to a newer
version, the patch might no longer apply.
If this is the case and assuming the patch is still needed,
you must modify the patch file so that it does apply.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='moving-to-the-yocto-project-1.3-release'>
<title>Moving to the Yocto Project 1.3 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 1.3 Release from the prior release.
</para>
<section id='1.3-local-configuration'>
<title>Local Configuration</title>
<para>
Differences include changes for
<link linkend='var-SSTATE_MIRRORS'><filename>SSTATE_MIRRORS</filename></link>
and <filename>bblayers.conf</filename>.
</para>
<section id='migration-1.3-sstate-mirrors'>
<title>SSTATE_MIRRORS</title>
<para>
The shared state cache (sstate-cache), as pointed to by
<link linkend='var-SSTATE_DIR'><filename>SSTATE_DIR</filename></link>,
by default now has two-character subdirectories to prevent
issues arising from too many files in the same directory.
Also, native sstate-cache packages, which are built to run
on the host system, will go into a subdirectory named using
the distro ID string.
If you copy the newly structured sstate-cache to a mirror
location (either local or remote) and then point to it in
<link linkend='var-SSTATE_MIRRORS'><filename>SSTATE_MIRRORS</filename></link>,
you need to append "PATH" to the end of the mirror URL so that
the path used by BitBake before the mirror substitution is
appended to the path used to access the mirror.
Here is an example:
<literallayout class='monospaced'>
SSTATE_MIRRORS = "file://.* http://<replaceable>someserver</replaceable>.tld/share/sstate/PATH"
</literallayout>
</para>
</section>
<section id='migration-1.3-bblayers-conf'>
<title>bblayers.conf</title>
<para>
The <filename>meta-yocto</filename> layer consists of two parts
that correspond to the Poky reference distribution and the
reference hardware Board Support Packages (BSPs), respectively:
<filename>meta-yocto</filename> and
<filename>meta-yocto-bsp</filename>.
When running BitBake for the first time after upgrading,
your <filename>conf/bblayers.conf</filename> file will be
updated to handle this change and you will be asked to
re-run or restart for the changes to take effect.
</para>
</section>
</section>
<section id='1.3-recipes'>
<title>Recipes</title>
<para>
Differences include changes for the following:
<itemizedlist>
<listitem><para>Python function whitespace</para></listitem>
<listitem><para><filename>proto=</filename> in <filename>SRC_URI</filename></para></listitem>
<listitem><para><filename>nativesdk</filename></para></listitem>
<listitem><para>Task recipes</para></listitem>
<listitem><para><filename>IMAGE_FEATURES</filename></para></listitem>
<listitem><para>Removed recipes</para></listitem>
</itemizedlist>
</para>
<section id='migration-1.3-python-function-whitespace'>
<title>Python Function Whitespace</title>
<para>
All Python functions must now use four spaces for indentation.
Previously, an inconsistent mix of spaces and tabs existed,
which made extending these functions using
<filename>_append</filename> or <filename>_prepend</filename>
complicated given that Python treats whitespace as
syntactically significant.
If you are defining or extending any Python functions (e.g.
<filename>populate_packages</filename>, <filename>do_unpack</filename>,
<filename>do_patch</filename> and so forth) in custom recipes
or classes, you need to ensure you are using consistent
four-space indentation.
</para>
</section>
<section id='migration-1.3-proto=-in-src-uri'>
<title>proto= in SRC_URI</title>
<para>
Any use of <filename>proto=</filename> in
<link linkend='var-SRC_URI'><filename>SRC_URI</filename></link>
needs to be changed to <filename>protocol=</filename>.
In particular, this applies to the following URIs:
<itemizedlist>
<listitem><para><filename>svn://</filename></para></listitem>
<listitem><para><filename>bzr://</filename></para></listitem>
<listitem><para><filename>hg://</filename></para></listitem>
<listitem><para><filename>osc://</filename></para></listitem>
</itemizedlist>
Other URIs were already using <filename>protocol=</filename>.
This change improves consistency.
</para>
</section>
<section id='migration-1.3-nativesdk'>
<title>nativesdk</title>
<para>
The suffix <filename>nativesdk</filename> is now implemented
as a prefix, which simplifies a lot of the packaging code for
<filename>nativesdk</filename> recipes.
All custom <filename>nativesdk</filename> recipes, which are
relocatable packages that are native to
<link linkend='var-SDK_ARCH'><filename>SDK_ARCH</filename></link>,
and any references need to be updated to use
<filename>nativesdk-*</filename> instead of
<filename>*-nativesdk</filename>.
</para>
</section>
<section id='migration-1.3-task-recipes'>
<title>Task Recipes</title>
<para>
"Task" recipes are now known as "Package groups" and have
been renamed from <filename>task-*.bb</filename> to
<filename>packagegroup-*.bb</filename>.
Existing references to the previous <filename>task-*</filename>
names should work in most cases as there is an automatic
upgrade path for most packages.
However, you should update references in your own recipes and
configurations as they could be removed in future releases.
You should also rename any custom <filename>task-*</filename>
recipes to <filename>packagegroup-*</filename>, and change
them to inherit <filename>packagegroup</filename> instead of
<filename>task</filename>, as well as taking the opportunity
to remove anything now handled by
<filename>packagegroup.bbclass</filename>, such as providing
<filename>-dev</filename> and <filename>-dbg</filename>
packages, setting
<link linkend='var-LIC_FILES_CHKSUM'><filename>LIC_FILES_CHKSUM</filename></link>,
and so forth.
See the
"<link linkend='ref-classes-packagegroup'><filename>packagegroup.bbclass</filename></link>"
section for further details.
</para>
</section>
<section id='migration-1.3-image-features'>
<title>IMAGE_FEATURES</title>
<para>
Image recipes that previously included "apps-console-core"
in <link linkend='var-IMAGE_FEATURES'><filename>IMAGE_FEATURES</filename></link>
should now include "splash" instead to enable the boot-up
splash screen.
Retaining "apps-console-core" will still include the splash
screen but generates a warning.
The "apps-x11-core" and "apps-x11-games"
<filename>IMAGE_FEATURES</filename> features have been removed.
</para>
</section>
<section id='migration-1.3-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed.
For most of them, it is unlikely that you would have any
references to them in your own
<link linkend='metadata'>Metadata</link>.
However, you should check your metadata against this list to be sure:
<itemizedlist>
<listitem><para><emphasis><filename>libx11-trim</filename></emphasis>:
Replaced by <filename>libx11</filename>, which has a negligible
size difference with modern Xorg.</para></listitem>
<listitem><para><emphasis><filename>xserver-xorg-lite</filename></emphasis>:
Use <filename>xserver-xorg</filename>, which has a negligible
size difference when DRI and GLX modules are not installed.</para></listitem>
<listitem><para><emphasis><filename>xserver-kdrive</filename></emphasis>:
Effectively unmaintained for many years.</para></listitem>
<listitem><para><emphasis><filename>mesa-xlib</filename></emphasis>:
No longer serves any purpose.</para></listitem>
<listitem><para><emphasis><filename>galago</filename></emphasis>:
Replaced by telepathy.</para></listitem>
<listitem><para><emphasis><filename>gail</filename></emphasis>:
Functionality was integrated into GTK+ 2.13.</para></listitem>
<listitem><para><emphasis><filename>eggdbus</filename></emphasis>:
No longer needed.</para></listitem>
<listitem><para><emphasis><filename>gcc-*-intermediate</filename></emphasis>:
The build has been restructured to avoid the need for
this step.</para></listitem>
<listitem><para><emphasis><filename>libgsmd</filename></emphasis>:
Unmaintained for many years.
Functionality now provided by
<filename>ofono</filename> instead.</para></listitem>
<listitem><para><emphasis>contacts, dates, tasks, eds-tools</emphasis>:
Largely unmaintained PIM application suite.
It has been moved to <filename>meta-gnome</filename>
in <filename>meta-openembedded</filename>.</para></listitem>
</itemizedlist>
In addition to the previously listed changes, the
<filename>meta-demoapps</filename> directory has also been removed
because the recipes in it were not being maintained and many
had become obsolete or broken.
Additionally, these recipes were not parsed in the default configuration.
Many of these recipes are already provided in an updated and
maintained form within the OpenEmbedded community layers such as
<filename>meta-oe</filename> and <filename>meta-gnome</filename>.
For the remainder, you can now find them in the
<filename>meta-extras</filename> repository, which is in the
Yocto Project
<ulink url='&YOCTO_DOCS_OM_URL;#source-repositories'>Source Repositories</ulink>.
</para>
</section>
</section>
<section id='1.3-linux-kernel-naming'>
<title>Linux Kernel Naming</title>
<para>
The naming scheme for kernel output binaries has been changed to
now include
<link linkend='var-PE'><filename>PE</filename></link> as part of the
filename:
<literallayout class='monospaced'>
KERNEL_IMAGE_BASE_NAME ?= "${KERNEL_IMAGETYPE}-${PE}-${PV}-${PR}-${MACHINE}-${DATETIME}"
</literallayout>
</para>
<para>
Because the <filename>PE</filename> variable is not set by default,
these binary files could result with names that include two dash
characters.
Here is an example:
<literallayout class='monospaced'>
bzImage--3.10.9+git0+cd502a8814_7144bcc4b8-r0-qemux86-64-20130830085431.bin
</literallayout>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-1.4-release'>
<title>Moving to the Yocto Project 1.4 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 1.4 Release from the prior release.
</para>
<section id='migration-1.4-bitbake'>
<title>BitBake</title>
<para>
Differences include the following:
<itemizedlist>
<listitem><para><emphasis>Comment Continuation:</emphasis>
If a comment ends with a line continuation (\) character,
then the next line must also be a comment.
Any instance where this is not the case, now triggers
a warning.
You must either remove the continuation character, or be
sure the next line is a comment.
</para></listitem>
<listitem><para><emphasis>Package Name Overrides:</emphasis>
The runtime package specific variables
<link linkend='var-RDEPENDS'><filename>RDEPENDS</filename></link>,
<link linkend='var-RRECOMMENDS'><filename>RRECOMMENDS</filename></link>,
<link linkend='var-RSUGGESTS'><filename>RSUGGESTS</filename></link>,
<link linkend='var-RPROVIDES'><filename>RPROVIDES</filename></link>,
<link linkend='var-RCONFLICTS'><filename>RCONFLICTS</filename></link>,
<link linkend='var-RREPLACES'><filename>RREPLACES</filename></link>,
<link linkend='var-FILES'><filename>FILES</filename></link>,
<link linkend='var-ALLOW_EMPTY'><filename>ALLOW_EMPTY</filename></link>,
and the pre, post, install, and uninstall script functions
<filename>pkg_preinst</filename>,
<filename>pkg_postinst</filename>,
<filename>pkg_prerm</filename>, and
<filename>pkg_postrm</filename> should always have a
package name override.
For example, use <filename>RDEPENDS_${PN}</filename> for
the main package instead of <filename>RDEPENDS</filename>.
BitBake uses more strict checks when it parses recipes.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.4-build-behavior'>
<title>Build Behavior</title>
<para>
Differences include the following:
<itemizedlist>
<listitem><para><emphasis>Shared State Code:</emphasis>
The shared state code has been optimized to avoid running
unnecessary tasks.
For example, the following no longer populates the target
sysroot since that is not necessary:
<literallayout class='monospaced'>
$ bitbake -c rootfs <replaceable>some-image</replaceable>
</literallayout>
Instead, the system just needs to extract the output
package contents, re-create the packages, and construct
the root filesystem.
This change is unlikely to cause any problems unless
you have missing declared dependencies.
</para></listitem>
<listitem><para><emphasis>Scanning Directory Names:</emphasis>
When scanning for files in
<link linkend='var-SRC_URI'><filename>SRC_URI</filename></link>,
the build system now uses
<link linkend='var-FILESOVERRIDES'><filename>FILESOVERRIDES</filename></link>
instead of <link linkend='var-OVERRIDES'><filename>OVERRIDES</filename></link>
for the directory names.
In general, the values previously in
<filename>OVERRIDES</filename> are now in
<filename>FILESOVERRIDES</filename> as well.
However, if you relied upon an additional value
you previously added to <filename>OVERRIDES</filename>,
you might now need to add it to
<filename>FILESOVERRIDES</filename> unless you are already
adding it through the
<link linkend='var-MACHINEOVERRIDES'><filename>MACHINEOVERRIDES</filename></link>
or <link linkend='var-DISTROOVERRIDES'><filename>DISTROOVERRIDES</filename></link>
variables, as appropriate.
For more related changes, see the
"<link linkend='migration-1.4-variables'>Variables</link>"
section.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.4-proxies-and-fetching-source'>
<title>Proxies and Fetching Source</title>
<para>
A new <filename>oe-git-proxy</filename> script has been added to
replace previous methods of handling proxies and fetching source
from Git.
See the <filename>meta-yocto/conf/site.conf.sample</filename> file
for information on how to use this script.
</para>
</section>
<section id='migration-1.4-custom-interfaces-file-netbase-change'>
<title>Custom Interfaces File (netbase change)</title>
<para>
If you have created your own custom
<filename>etc/network/interfaces</filename> file by creating
an append file for the <filename>netbase</filename> recipe,
you now need to create an append file for the
<filename>init-ifupdown</filename> recipe instead, which you can
find in the
<link linkend='source-directory'>Source Directory</link>
at <filename>meta/recipes-core/init-ifupdown</filename>.
For information on how to use append files, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#using-bbappend-files'>Using .bbappend Files</ulink>"
section in the Yocto Project Development Tasks Manual.
</para>
</section>
<section id='migration-1.4-remote-debugging'>
<title>Remote Debugging</title>
<para>
Support for remote debugging with the Eclipse IDE is now
separated into an image feature
(<filename>eclipse-debug</filename>) that corresponds to the
<filename>packagegroup-core-eclipse-debug</filename> package group.
Previously, the debugging feature was included through the
<filename>tools-debug</filename> image feature, which corresponds
to the <filename>packagegroup-core-tools-debug</filename>
package group.
</para>
</section>
<section id='migration-1.4-variables'>
<title>Variables</title>
<para>
The following variables have changed:
<itemizedlist>
<listitem><para><emphasis><filename>SANITY_TESTED_DISTROS</filename>:</emphasis>
This variable now uses a distribution ID, which is composed
of the host distributor ID followed by the release.
Previously,
<link linkend='var-SANITY_TESTED_DISTROS'><filename>SANITY_TESTED_DISTROS</filename></link>
was composed of the description field.
For example, "Ubuntu 12.10" becomes "Ubuntu-12.10".
You do not need to worry about this change if you are not
specifically setting this variable, or if you are
specifically setting it to "".
</para></listitem>
<listitem><para><emphasis><filename>SRC_URI</filename>:</emphasis>
The <filename>${</filename><link linkend='var-PN'><filename>PN</filename></link><filename>}</filename>,
<filename>${</filename><link linkend='var-PF'><filename>PF</filename></link><filename>}</filename>,
<filename>${</filename><link linkend='var-P'><filename>P</filename></link><filename>}</filename>,
and <filename>FILE_DIRNAME</filename> directories have been
dropped from the default value of the
<link linkend='var-FILESPATH'><filename>FILESPATH</filename></link>
variable, which is used as the search path for finding files
referred to in
<link linkend='var-SRC_URI'><filename>SRC_URI</filename></link>.
If you have a recipe that relied upon these directories,
which would be unusual, then you will need to add the
appropriate paths within the recipe or, alternatively,
rearrange the files.
The most common locations are still covered by
<filename>${BP}</filename>, <filename>${BPN}</filename>,
and "files", which all remain in the default value of
<link linkend='var-FILESPATH'><filename>FILESPATH</filename></link>.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-target-package-management-with-rpm'>
<title>Target Package Management with RPM</title>
<para>
If runtime package management is enabled and the RPM backend
is selected, Smart is now installed for package download, dependency
resolution, and upgrades instead of Zypper.
For more information on how to use Smart, run the following command
on the target:
<literallayout class='monospaced'>
smart --help
</literallayout>
</para>
</section>
<section id='migration-1.4-recipes-moved'>
<title>Recipes Moved</title>
<para>
The following recipes were moved from their previous locations
because they are no longer used by anything in
the OpenEmbedded-Core:
<itemizedlist>
<listitem><para><emphasis><filename>clutter-box2d</filename>:</emphasis>
Now resides in the <filename>meta-oe</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>evolution-data-server</filename>:</emphasis>
Now resides in the <filename>meta-gnome</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>gthumb</filename>:</emphasis>
Now resides in the <filename>meta-gnome</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>gtkhtml2</filename>:</emphasis>
Now resides in the <filename>meta-oe</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>gupnp</filename>:</emphasis>
Now resides in the <filename>meta-multimedia</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>gypsy</filename>:</emphasis>
Now resides in the <filename>meta-oe</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>libcanberra</filename>:</emphasis>
Now resides in the <filename>meta-gnome</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>libgdata</filename>:</emphasis>
Now resides in the <filename>meta-gnome</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>libmusicbrainz</filename>:</emphasis>
Now resides in the <filename>meta-multimedia</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>metacity</filename>:</emphasis>
Now resides in the <filename>meta-gnome</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>polkit</filename>:</emphasis>
Now resides in the <filename>meta-oe</filename> layer.
</para></listitem>
<listitem><para><emphasis><filename>zeroconf</filename>:</emphasis>
Now resides in the <filename>meta-networking</filename> layer.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.4-removals-and-renames'>
<title>Removals and Renames</title>
<para>
The following list shows what has been removed or renamed:
<itemizedlist>
<listitem><para><emphasis><filename>evieext</filename>:</emphasis>
Removed because it has been removed from
<filename>xserver</filename> since 2008.
</para></listitem>
<listitem><para><emphasis>Gtk+ DirectFB:</emphasis>
Removed support because upstream Gtk+ no longer supports it
as of version 2.18.
</para></listitem>
<listitem><para><emphasis><filename>libxfontcache / xfontcacheproto</filename>:</emphasis>
Removed because they were removed from the Xorg server in 2008.
</para></listitem>
<listitem><para><emphasis><filename>libxp / libxprintapputil / libxprintutil / printproto</filename>:</emphasis>
Removed because the XPrint server was removed from
Xorg in 2008.
</para></listitem>
<listitem><para><emphasis><filename>libxtrap / xtrapproto</filename>:</emphasis>
Removed because their functionality was broken upstream.
</para></listitem>
<listitem><para><emphasis>linux-yocto 3.0 kernel:</emphasis>
Removed with linux-yocto 3.8 kernel being added.
The linux-yocto 3.2 and linux-yocto 3.4 kernels remain
as part of the release.
</para></listitem>
<listitem><para><emphasis><filename>lsbsetup</filename>:</emphasis>
Removed with functionality now provided by
<filename>lsbtest</filename>.
</para></listitem>
<listitem><para><emphasis><filename>matchbox-stroke</filename>:</emphasis>
Removed because it was never more than a proof-of-concept.
</para></listitem>
<listitem><para><emphasis><filename>matchbox-wm-2 / matchbox-theme-sato-2</filename>:</emphasis>
Removed because they are not maintained.
However, <filename>matchbox-wm</filename> and
<filename>matchbox-theme-sato</filename> are still
provided.
</para></listitem>
<listitem><para><emphasis><filename>mesa-dri</filename>:</emphasis>
Renamed to <filename>mesa</filename>.
</para></listitem>
<listitem><para><emphasis><filename>mesa-xlib</filename>:</emphasis>
Removed because it was no longer useful.
</para></listitem>
<listitem><para><emphasis><filename>mutter</filename>:</emphasis>
Removed because nothing ever uses it and the recipe is
very old.
</para></listitem>
<listitem><para><emphasis><filename>orinoco-conf</filename>:</emphasis>
Removed because it has become obsolete.
</para></listitem>
<listitem><para><emphasis><filename>update-modules</filename>:</emphasis>
Removed because it is no longer used.
The kernel module <filename>postinstall</filename> and
<filename>postrm</filename> scripts can now do the same
task without the use of this script.
</para></listitem>
<listitem><para><emphasis><filename>web</filename>:</emphasis>
Removed because it is not maintained. Superseded by
<filename>web-webkit</filename>.
</para></listitem>
<listitem><para><emphasis><filename>xf86bigfontproto</filename>:</emphasis>
Removed because upstream it has been disabled by default
since 2007.
Nothing uses <filename>xf86bigfontproto</filename>.
</para></listitem>
<listitem><para><emphasis><filename>xf86rushproto</filename>:</emphasis>
Removed because its dependency in
<filename>xserver</filename> was spurious and it was
removed in 2005.
</para></listitem>
<listitem><para><emphasis><filename>zypper / libzypp / sat-solver</filename>:</emphasis>
Removed and been functionally replaced with Smart
(<filename>python-smartpm</filename>) when RPM packaging
is used and package management is enabled on the target.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-1.5-release'>
<title>Moving to the Yocto Project 1.5 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 1.5 Release from the prior release.
</para>
<section id='migration-1.5-host-dependency-changes'>
<title>Host Dependency Changes</title>
<para>
The OpenEmbedded build system now has some additional requirements
on the host system:
<itemizedlist>
<listitem><para>Python 2.7.3+</para></listitem>
<listitem><para>Tar 1.24+</para></listitem>
<listitem><para>Git 1.7.8+</para></listitem>
<listitem><para>Patched version of Make if you are using
3.82.
Most distributions that provide Make 3.82 use the patched
version.</para></listitem>
</itemizedlist>
If the Linux distribution you are using on your build host
does not provide packages for these, you can install and use
the Buildtools tarball, which provides an SDK-like environment
containing them.
</para>
<para>
For more information on this requirement, see the
"<link linkend='required-git-tar-python-and-gcc-versions'>Required Git, tar, Python and gcc Versions</link>"
section.
</para>
</section>
<section id='migration-1.5-atom-pc-bsp'>
<title><filename>atom-pc</filename> Board Support Package (BSP)</title>
<para>
The <filename>atom-pc</filename> hardware reference BSP has been
replaced by a <filename>genericx86</filename> BSP.
This BSP is not necessarily guaranteed to work on all x86
hardware, but it will run on a wider range of systems than the
<filename>atom-pc</filename> did.
<note>
Additionally, a <filename>genericx86-64</filename> BSP has
been added for 64-bit Atom systems.
</note>
</para>
</section>
<section id='migration-1.5-bitbake'>
<title>BitBake</title>
<para>
The following changes have been made that relate to BitBake:
<itemizedlist>
<listitem><para>
BitBake now supports a <filename>_remove</filename>
operator.
The addition of this operator means you will have to
rename any items in recipe space (functions, variables)
whose names currently contain
<filename>_remove_</filename> or end with
<filename>_remove</filename> to avoid unexpected behavior.
</para></listitem>
<listitem><para>
BitBake's global method pool has been removed.
This method is not particularly useful and led to clashes
between recipes containing functions that had the
same name.</para></listitem>
<listitem><para>
The "none" server backend has been removed.
The "process" server backend has been serving well as the
default for a long time now.</para></listitem>
<listitem><para>
The <filename>bitbake-runtask</filename> script has been
removed.</para></listitem>
<listitem><para>
<filename>${</filename><link linkend='var-P'><filename>P</filename></link><filename>}</filename>
and
<filename>${</filename><link linkend='var-PF'><filename>PF</filename></link><filename>}</filename>
are no longer added to
<link linkend='var-PROVIDES'><filename>PROVIDES</filename></link>
by default in <filename>bitbake.conf</filename>.
These version-specific <filename>PROVIDES</filename>
items were seldom used.
Attempting to use them could result in two versions being
built simultaneously rather than just one version due to
the way BitBake resolves dependencies.</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.5-qa-warnings'>
<title>QA Warnings</title>
<para>
The following changes have been made to the package QA checks:
<itemizedlist>
<listitem><para>
If you have customized
<link linkend='var-ERROR_QA'><filename>ERROR_QA</filename></link>
or <link linkend='var-WARN_QA'><filename>WARN_QA</filename></link>
values in your configuration, check that they contain all of
the issues that you wish to be reported.
Previous Yocto Project versions contained a bug that meant
that any item not mentioned in <filename>ERROR_QA</filename>
or <filename>WARN_QA</filename> would be treated as a
warning.
Consequently, several important items were not already in
the default value of <filename>WARN_QA</filename>.
All of the possible QA checks are now documented in the
"<link linkend='ref-classes-insane'><filename>insane.bbclass</filename></link>"
section.</para></listitem>
<listitem><para>
An additional QA check has been added to check if
<filename>/usr/share/info/dir</filename> is being installed.
Your recipe should delete this file within
<link linkend='ref-tasks-install'><filename>do_install</filename></link>
if "make install" is installing it.
</para></listitem>
<listitem><para>
If you are using the buildhistory class, the check for the
package version going backwards is now controlled using a
standard QA check.
Thus, if you have customized your
<filename>ERROR_QA</filename> or
<filename>WARN_QA</filename> values and still wish to have
this check performed, you should add
"version-going-backwards" to your value for one or the
other variables depending on how you wish it to be handled.
See the documented QA checks in the
"<link linkend='ref-classes-insane'><filename>insane.bbclass</filename></link>"
section.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.5-directory-layout-changes'>
<title>Directory Layout Changes</title>
<para>
The following directory changes exist:
<itemizedlist>
<listitem><para>
Output SDK installer files are now named to include the
image name and tuning architecture through the
<link linkend='var-SDK_NAME'><filename>SDK_NAME</filename></link>
variable.</para></listitem>
<listitem><para>
Images and related files are now installed into a directory
that is specific to the machine, instead of a parent
directory containing output files for multiple machines.
The
<link linkend='var-DEPLOY_DIR_IMAGE'><filename>DEPLOY_DIR_IMAGE</filename></link>
variable continues to point to the directory containing
images for the current
<link linkend='var-MACHINE'><filename>MACHINE</filename></link>
and should be used anywhere there is a need to refer to
this directory.
The <filename>runqemu</filename> script now uses this
variable to find images and kernel binaries and will use
BitBake to determine the directory.
Alternatively, you can set the
<filename>DEPLOY_DIR_IMAGE</filename> variable in the
external environment.</para></listitem>
<listitem><para>
When buildhistory is enabled, its output is now written
under the
<link linkend='build-directory'>Build Directory</link>
rather than
<link linkend='var-TMPDIR'><filename>TMPDIR</filename></link>.
Doing so makes it easier to delete
<filename>TMPDIR</filename> and preserve the build history.
Additionally, data for produced SDKs is now split by
<link linkend='var-IMAGE_NAME'><filename>IMAGE_NAME</filename></link>.
</para></listitem>
<listitem><para>
The <filename>pkgdata</filename> directory produced as
part of the packaging process has been collapsed into a
single machine-specific directory.
This directory is located under
<filename>sysroots</filename> and uses a machine-specific
name (i.e.
<filename>tmp/sysroots/<replaceable>machine</replaceable>/pkgdata</filename>).
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.5-shortened-git-srcrev-values'>
<title>Shortened Git <filename>SRCREV</filename> Values</title>
<para>
BitBake will now shorten revisions from Git repositories from the
normal 40 characters down to 10 characters within
<link linkend='var-SRCPV'><filename>SRCPV</filename></link>
for improved usability in path and file names.
This change should be safe within contexts where these revisions
are used because the chances of spatially close collisions
is very low.
Distant collisions are not a major issue in the way
the values are used.
</para>
</section>
<section id='migration-1.5-image-features'>
<title><filename>IMAGE_FEATURES</filename></title>
<para>
The following changes have been made that relate to
<link linkend='var-IMAGE_FEATURES'><filename>IMAGE_FEATURES</filename></link>:
<itemizedlist>
<listitem><para>
The value of <filename>IMAGE_FEATURES</filename> is now
validated to ensure invalid feature items are not added.
Some users mistakenly add package names to this variable
instead of using
<link linkend='var-IMAGE_INSTALL'><filename>IMAGE_INSTALL</filename></link>
in order to have the package added to the image, which does
not work.
This change is intended to catch those kinds of situations.
Valid <filename>IMAGE_FEATURES</filename> are drawn from
<filename>PACKAGE_GROUP</filename> definitions,
<link linkend='var-COMPLEMENTARY_GLOB'><filename>COMPLEMENTARY_GLOB</filename></link>
and a new "validitems" varflag on
<filename>IMAGE_FEATURES</filename>.
The "validitems" varflag change allows additional features
to be added if they are not provided using the previous
two mechanisms.
</para></listitem>
<listitem><para>
The previously deprecated "apps-console-core"
<filename>IMAGE_FEATURES</filename> item is no longer
supported.
Add "splash" to <filename>IMAGE_FEATURES</filename> if you
wish to have the splash screen enabled, since this is
all that apps-console-core was doing.</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.5-run'>
<title><filename>/run</filename></title>
<para>
The <filename>/run</filename> directory from the Filesystem
Hierarchy Standard 3.0 has been introduced.
You can find some of the implications for this change
<ulink url='http://cgit.openembedded.org/openembedded-core/commit/?id=0e326280a15b0f2c4ef2ef4ec441f63f55b75873'>here</ulink>.
The change also means that recipes that install files to
<filename>/var/run</filename> must be changed.
You can find a guide on how to make these changes
<ulink url='http://permalink.gmane.org/gmane.comp.handhelds.openembedded/58530'>here</ulink>.
</para>
</section>
<section id='migration-1.5-removal-of-package-manager-database-within-image-recipes'>
<title>Removal of Package Manager Database Within Image Recipes</title>
<para>
The image <filename>core-image-minimal</filename> no longer adds
<filename>remove_packaging_data_files</filename> to
<link linkend='var-ROOTFS_POSTPROCESS_COMMAND'><filename>ROOTFS_POSTPROCESS_COMMAND</filename></link>.
This addition is now handled automatically when "package-management"
is not in
<link linkend='var-IMAGE_FEATURES'><filename>IMAGE_FEATURES</filename></link>.
If you have custom image recipes that make this addition,
you should remove the lines, as they are not needed and might
interfere with correct operation of postinstall scripts.
</para>
</section>
<section id='migration-1.5-images-now-rebuild-only-on-changes-instead-of-every-time'>
<title>Images Now Rebuild Only on Changes Instead of Every Time</title>
<para>
The
<link linkend='ref-tasks-rootfs'><filename>do_rootfs</filename></link>
and other related image
construction tasks are no longer marked as "nostamp".
Consequently, they will only be re-executed when their inputs have
changed.
Previous versions of the OpenEmbedded build system always rebuilt
the image when requested rather when necessary.
</para>
</section>
<section id='migration-1.5-task-recipes'>
<title>Task Recipes</title>
<para>
The previously deprecated <filename>task.bbclass</filename> has
now been dropped.
For recipes that previously inherited from this class, you should
rename them from <filename>task-*</filename> to
<filename>packagegroup-*</filename> and inherit packagegroup
instead.
</para>
<para>
For more information, see the
"<link linkend='ref-classes-packagegroup'><filename>packagegroup.bbclass</filename></link>"
section.
</para>
</section>
<section id='migration-1.5-busybox'>
<title>BusyBox</title>
<para>
By default, we now split BusyBox into two binaries:
one that is suid root for those components that need it, and
another for the rest of the components.
Splitting BusyBox allows for optimization that eliminates the
<filename>tinylogin</filename> recipe as recommended by upstream.
You can disable this split by setting
<link linkend='var-BUSYBOX_SPLIT_SUID'><filename>BUSYBOX_SPLIT_SUID</filename></link>
to "0".
</para>
</section>
<section id='migration-1.5-automated-image-testing'>
<title>Automated Image Testing</title>
<para>
A new automated image testing framework has been added
through the
<link linkend='ref-classes-testimage*'><filename>testimage.bbclass</filename></link>
class.
This framework replaces the older
<filename>imagetest-qemu</filename> framework.
</para>
<para>
You can learn more about performing automated image tests in the
"<ulink url='&YOCTO_DOCS_DEV_URL;#performing-automated-runtime-testing'>Performing Automated Runtime Testing</ulink>"
section in the Yocto Project Development Tasks Manual.
</para>
</section>
<section id='migration-1.5-build-history'>
<title>Build History</title>
<para>
Following are changes to Build History:
<itemizedlist>
<listitem><para>
Installed package sizes:
<filename>installed-package-sizes.txt</filename> for an
image now records the size of the files installed by each
package instead of the size of each compressed package
archive file.</para></listitem>
<listitem><para>
The dependency graphs (<filename>depends*.dot</filename>)
now use the actual package names instead of replacing
dashes, dots and plus signs with underscores.
</para></listitem>
<listitem><para>
The <filename>buildhistory-diff</filename> and
<filename>buildhistory-collect-srcrevs</filename>
utilities have improved command-line handling.
Use the <filename>--help</filename> option for
each utility for more information on the new syntax.
</para></listitem>
</itemizedlist>
For more information on Build History, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#maintaining-build-output-quality'>Maintaining Build Output Quality</ulink>"
section in the Yocto Project Development Tasks Manual.
</para>
</section>
<section id='migration-1.5-udev'>
<title><filename>udev</filename></title>
<para>
Following are changes to <filename>udev</filename>:
<itemizedlist>
<listitem><para>
<filename>udev</filename> no longer brings in
<filename>udev-extraconf</filename> automatically
through
<link linkend='var-RRECOMMENDS'><filename>RRECOMMENDS</filename></link>,
since this was originally intended to be optional.
If you need the extra rules, then add
<filename>udev-extraconf</filename> to your image.
</para></listitem>
<listitem><para>
<filename>udev</filename> no longer brings in
<filename>pciutils-ids</filename> or
<filename>usbutils-ids</filename> through
<filename>RRECOMMENDS</filename>.
These are not needed by <filename>udev</filename> itself
and removing them saves around 350KB.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.5-removed-renamed-recipes'>
<title>Removed and Renamed Recipes</title>
<itemizedlist>
<listitem><para>
The <filename>linux-yocto</filename> 3.2 kernel has been
removed.</para></listitem>
<listitem><para>
<filename>libtool-nativesdk</filename> has been renamed to
<filename>nativesdk-libtool</filename>.</para></listitem>
<listitem><para>
<filename>tinylogin</filename> has been removed.
It has been replaced by a suid portion of Busybox.
See the
"<link linkend='migration-1.5-busybox'>BusyBox</link>" section
for more information.</para></listitem>
<listitem><para>
<filename>external-python-tarball</filename> has been renamed
to <filename>buildtools-tarball</filename>.
</para></listitem>
<listitem><para>
<filename>web-webkit</filename> has been removed.
It has been functionally replaced by
<filename>midori</filename>.</para></listitem>
<listitem><para>
<filename>imake</filename> has been removed.
It is no longer needed by any other recipe.
</para></listitem>
<listitem><para>
<filename>transfig-native</filename> has been removed.
It is no longer needed by any other recipe.
</para></listitem>
<listitem><para>
<filename>anjuta-remote-run</filename> has been removed.
Anjuta IDE integration has not been officially supported for
several releases.</para></listitem>
</itemizedlist>
</section>
<section id='migration-1.5-other-changes'>
<title>Other Changes</title>
<para>
Following is a list of short entries describing other changes:
<itemizedlist>
<listitem><para>
<filename>run-postinsts</filename>: Make this generic.
</para></listitem>
<listitem><para>
<filename>base-files</filename>: Remove the unnecessary
<filename>media/</filename><replaceable>xxx</replaceable> directories.
</para></listitem>
<listitem><para>
<filename>alsa-state</filename>: Provide an empty
<filename>asound.conf</filename> by default.
</para></listitem>
<listitem><para>
<filename>classes/image</filename>: Ensure
<link linkend='var-BAD_RECOMMENDATIONS'><filename>BAD_RECOMMENDATIONS</filename></link>
supports pre-renamed package names.</para></listitem>
<listitem><para>
<filename>classes/rootfs_rpm</filename>: Implement
<filename>BAD_RECOMMENDATIONS</filename> for RPM.
</para></listitem>
<listitem><para>
<filename>systemd</filename>: Remove
<filename>systemd_unitdir</filename> if
<filename>systemd</filename> is not in
<link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link>.
</para></listitem>
<listitem><para>
<filename>systemd</filename>: Remove
<filename>init.d</filename> dir if
<filename>systemd</filename> unit file is present and
<filename>sysvinit</filename> is not a distro feature.
</para></listitem>
<listitem><para>
<filename>libpam</filename>: Deny all services for the
<filename>OTHER</filename> entries.
</para></listitem>
<listitem><para>
<filename>image.bbclass</filename>: Move
<filename>runtime_mapping_rename</filename> to avoid
conflict with <filename>multilib</filename>.
See
<ulink url='https://bugzilla.yoctoproject.org/show_bug.cgi?id=4993'><filename>YOCTO #4993</filename></ulink>
in Bugzilla for more information.
</para></listitem>
<listitem><para>
<filename>linux-dtb</filename>: Use kernel build system
to generate the <filename>dtb</filename> files.
</para></listitem>
<listitem><para>
<filename>kern-tools</filename>: Switch from guilt to
new <filename>kgit-s2q</filename> tool.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-1.6-release'>
<title>Moving to the Yocto Project 1.6 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 1.6 Release from the prior release.
</para>
<section id='migration-1.6-archiver-class'>
<title><filename>archiver</filename> Class</title>
<para>
The
<link linkend='ref-classes-archiver'><filename>archiver</filename></link>
class has been rewritten and its configuration has been simplified.
For more details on the source archiver, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#maintaining-open-source-license-compliance-during-your-products-lifecycle'>Maintaining Open Source License Compliance During Your Product's Lifecycle</ulink>"
section in the Yocto Project Development Tasks Manual.
</para>
</section>
<section id='migration-1.6-packaging-changes'>
<title>Packaging Changes</title>
<para>
The following packaging changes have been made:
<itemizedlist>
<listitem><para>
The <filename>binutils</filename> recipe no longer produces
a <filename>binutils-symlinks</filename> package.
<filename>update-alternatives</filename> is now used to
handle the preferred <filename>binutils</filename>
variant on the target instead.
</para></listitem>
<listitem><para>
The tc (traffic control) utilities have been split out of
the main <filename>iproute2</filename> package and put
into the <filename>iproute2-tc</filename> package.
</para></listitem>
<listitem><para>
The <filename>gtk-engines</filename> schemas have been
moved to a dedicated
<filename>gtk-engines-schemas</filename> package.
</para></listitem>
<listitem><para>
The <filename>armv7a</filename> with thumb package
architecture suffix has changed.
The suffix for these packages with the thumb
optimization enabled is "t2" as it should be.
Use of this suffix was not the case in the 1.5 release.
Architecture names will change within package feeds as a
result.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.6-bitbake'>
<title>BitBake</title>
<para>
The following changes have been made to
<link linkend='bitbake-term'>BitBake</link>.
</para>
<section id='migration-1.6-matching-branch-requirement-for-git-fetching'>
<title>Matching Branch Requirement for Git Fetching</title>
<para>
When fetching source from a Git repository using
<link linkend='var-SRC_URI'><filename>SRC_URI</filename></link>,
BitBake will now validate the
<link linkend='var-SRCREV'><filename>SRCREV</filename></link>
value against the branch.
You can specify the branch using the following form:
<literallayout class='monospaced'>
SRC_URI = "git://server.name/repository;branch=<replaceable>branchname</replaceable>"
</literallayout>
If you do not specify a branch, BitBake looks
in the default "master" branch.
</para>
<para>
Alternatively, if you need to bypass this check (e.g.
if you are fetching a revision corresponding to a tag that
is not on any branch), you can add ";nobranch=1" to
the end of the URL within <filename>SRC_URI</filename>.
</para>
</section>
<section id='migration-1.6-bitbake-deps'>
<title>Python Definition substitutions</title>
<para>
BitBake had some previously deprecated Python definitions
within its <filename>bb</filename> module removed.
You should use their sub-module counterparts instead:
<itemizedlist>
<listitem><para><filename>bb.MalformedUrl</filename>:
Use <filename>bb.fetch.MalformedUrl</filename>.
</para></listitem>
<listitem><para><filename>bb.encodeurl</filename>:
Use <filename>bb.fetch.encodeurl</filename>.
</para></listitem>
<listitem><para><filename>bb.decodeurl</filename>:
Use <filename>bb.fetch.decodeurl</filename>
</para></listitem>
<listitem><para><filename>bb.mkdirhier</filename>:
Use <filename>bb.utils.mkdirhier</filename>.
</para></listitem>
<listitem><para><filename>bb.movefile</filename>:
Use <filename>bb.utils.movefile</filename>.
</para></listitem>
<listitem><para><filename>bb.copyfile</filename>:
Use <filename>bb.utils.copyfile</filename>.
</para></listitem>
<listitem><para><filename>bb.which</filename>:
Use <filename>bb.utils.which</filename>.
</para></listitem>
<listitem><para><filename>bb.vercmp_string</filename>:
Use <filename>bb.utils.vercmp_string</filename>.
</para></listitem>
<listitem><para><filename>bb.vercmp</filename>:
Use <filename>bb.utils.vercmp</filename>.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.6-bitbake-fetcher'>
<title>SVK Fetcher</title>
<para>
The SVK fetcher has been removed from BitBake.
</para>
</section>
<section id='migration-1.6-bitbake-console-output'>
<title>Console Output Error Redirection</title>
<para>
The BitBake console UI will now output errors to
<filename>stderr</filename> instead of
<filename>stdout</filename>.
Consequently, if you are piping or redirecting the output of
<filename>bitbake</filename> to somewhere else, and you wish
to retain the errors, you will need to add
<filename>2>&amp;1</filename> (or something similar) to the
end of your <filename>bitbake</filename> command line.
</para>
</section>
<section id='migration-1.6-task-taskname-overrides'>
<title><filename>task-</filename><replaceable>taskname</replaceable> Overrides</title>
<para>
<filename>task-</filename><replaceable>taskname</replaceable> overrides have been
adjusted so that tasks whose names contain underscores have the
underscores replaced by hyphens for the override so that they
now function properly.
For example, the task override for
<link linkend='ref-tasks-populate_sdk'><filename>do_populate_sdk</filename></link>
is <filename>task-populate-sdk</filename>.
</para>
</section>
</section>
<section id='migration-1.6-variable-changes'>
<title>Changes to Variables</title>
<para>
The following variables have changed.
For information on the OpenEmbedded build system variables, see the
"<link linkend='ref-variables-glos'>Variables Glossary</link>" Chapter.
</para>
<section id='migration-1.6-variable-changes-TMPDIR'>
<title><filename>TMPDIR</filename></title>
<para>
<link linkend='var-TMPDIR'><filename>TMPDIR</filename></link>
can no longer be on an NFS mount.
NFS does not offer full POSIX locking and inode consistency
and can cause unexpected issues if used to store
<filename>TMPDIR</filename>.
</para>
<para>
The check for this occurs on startup.
If <filename>TMPDIR</filename> is detected on an NFS mount,
an error occurs.
</para>
</section>
<section id='migration-1.6-variable-changes-PRINC'>
<title><filename>PRINC</filename></title>
<para>
The <filename>PRINC</filename>
variable has been deprecated and triggers a warning if
detected during a build.
For
<link linkend='var-PR'><filename>PR</filename></link>
increments on changes, use the PR service instead.
You can find out more about this service in the
"<ulink url='&YOCTO_DOCS_DEV_URL;#working-with-a-pr-service'>Working With a PR Service</ulink>"
section in the Yocto Project Development Tasks Manual.
</para>
</section>
<section id='migration-1.6-variable-changes-IMAGE_TYPES'>
<title><filename>IMAGE_TYPES</filename></title>
<para>
The "sum.jffs2" option for
<link linkend='var-IMAGE_TYPES'><filename>IMAGE_TYPES</filename></link>
has been replaced by the "jffs2.sum" option, which fits the
processing order.
</para>
</section>
<section id='migration-1.6-variable-changes-COPY_LIC_MANIFEST'>
<title><filename>COPY_LIC_MANIFEST</filename></title>
<para>
The
<link linkend='var-COPY_LIC_MANIFEST'><filename>COPY_LIC_MANIFEST</filename></link>
variable must
now be set to "1" rather than any value in order to enable
it.
</para>
</section>
<section id='migration-1.6-variable-changes-COPY_LIC_DIRS'>
<title><filename>COPY_LIC_DIRS</filename></title>
<para>
The
<link linkend='var-COPY_LIC_DIRS'><filename>COPY_LIC_DIRS</filename></link>
variable must
now be set to "1" rather than any value in order to enable
it.
</para>
</section>
<section id='migration-1.6-variable-changes-PACKAGE_GROUP'>
<title><filename>PACKAGE_GROUP</filename></title>
<para>
The
<filename>PACKAGE_GROUP</filename> variable has been renamed to
<link linkend='var-FEATURE_PACKAGES'><filename>FEATURE_PACKAGES</filename></link>
to more accurately reflect its purpose.
You can still use <filename>PACKAGE_GROUP</filename> but
the OpenEmbedded build system produces a warning message when
it encounters the variable.
</para>
</section>
<section id='migration-1.6-variable-changes-variable-entry-behavior'>
<title>Preprocess and Post Process Command Variable Behavior</title>
<para>
The following variables now expect a semicolon separated
list of functions to call and not arbitrary shell commands:
<literallayout class='monospaced'>
<link linkend='var-ROOTFS_PREPROCESS_COMMAND'>ROOTFS_PREPROCESS_COMMAND</link>
<link linkend='var-ROOTFS_POSTPROCESS_COMMAND'>ROOTFS_POSTPROCESS_COMMAND</link>
<link linkend='var-SDK_POSTPROCESS_COMMAND'>SDK_POSTPROCESS_COMMAND</link>
<link linkend='var-POPULATE_SDK_POST_TARGET_COMMAND'>POPULATE_SDK_POST_TARGET_COMMAND</link>
<link linkend='var-POPULATE_SDK_POST_HOST_COMMAND'>POPULATE_SDK_POST_HOST_COMMAND</link>
<link linkend='var-IMAGE_POSTPROCESS_COMMAND'>IMAGE_POSTPROCESS_COMMAND</link>
<link linkend='var-IMAGE_PREPROCESS_COMMAND'>IMAGE_PREPROCESS_COMMAND</link>
<link linkend='var-ROOTFS_POSTUNINSTALL_COMMAND'>ROOTFS_POSTUNINSTALL_COMMAND</link>
<link linkend='var-ROOTFS_POSTINSTALL_COMMAND'>ROOTFS_POSTINSTALL_COMMAND</link>
</literallayout>
For migration purposes, you can simply wrap shell commands in
a shell function and then call the function.
Here is an example:
<literallayout class='monospaced'>
my_postprocess_function() {
echo "hello" > ${IMAGE_ROOTFS}/hello.txt
}
ROOTFS_POSTPROCESS_COMMAND += "my_postprocess_function; "
</literallayout>
</para>
</section>
</section>
<section id='migration-1.6-package-test-ptest'>
<title>Package Test (ptest)</title>
<para>
Package Tests (ptest) are built but not installed by default.
For information on using Package Tests, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#testing-packages-with-ptest'>Testing Packages with ptest</ulink>"
section in the Yocto Project Development Tasks Manual.
For information on the <filename>ptest</filename> class, see the
"<link linkend='ref-classes-ptest'><filename>ptest.bbclass</filename></link>"
section.
</para>
</section>
<section id='migration-1.6-build-changes'>
<title>Build Changes</title>
<para>
Separate build and source directories have been enabled
by default for selected recipes where it is known to work
(a whitelist) and for all recipes that inherit the
<link linkend='ref-classes-cmake'><filename>cmake</filename></link>
class.
In future releases the
<link linkend='ref-classes-autotools'><filename>autotools</filename></link>
class will enable a separate build directory by default as
well.
Recipes building Autotools-based
software that fails to build with a separate build directory
should be changed to inherit from the
<link linkend='ref-classes-autotools'><filename>autotools-brokensep</filename></link>
class instead of the <filename>autotools</filename> or
<filename>autotools_stage</filename>classes.
</para>
</section>
<section id='migration-1.6-building-qemu-native'>
<title><filename>qemu-native</filename></title>
<para>
<filename>qemu-native</filename> now builds without
SDL-based graphical output support by default.
The following additional lines are needed in your
<filename>local.conf</filename> to enable it:
<literallayout class='monospaced'>
PACKAGECONFIG_pn-qemu-native = "sdl"
ASSUME_PROVIDED += "libsdl-native"
</literallayout>
<note>
The default <filename>local.conf</filename>
contains these statements.
Consequently, if you are building a headless system and using
a default <filename>local.conf</filename> file, you will need
comment these two lines out.
</note>
</para>
</section>
<section id='migration-1.6-core-image-basic'>
<title><filename>core-image-basic</filename></title>
<para>
<filename>core-image-basic</filename> has been renamed to
<filename>core-image-full-cmdline</filename>.
</para>
<para>
In addition to <filename>core-image-basic</filename> being renamed,
<filename>packagegroup-core-basic</filename> has been renamed to
<filename>packagegroup-core-full-cmdline</filename> to match.
</para>
</section>
<section id='migration-1.6-licensing'>
<title>Licensing</title>
<para>
The top-level <filename>LICENSE</filename> file has been changed
to better describe the license of the various components of
<link linkend='oe-core'>OE-Core</link>.
However, the licensing itself remains unchanged.
</para>
<para>
Normally, this change would not cause any side-effects.
However, some recipes point to this file within
<link linkend='var-LIC_FILES_CHKSUM'><filename>LIC_FILES_CHKSUM</filename></link>
(as <filename>${COREBASE}/LICENSE</filename>) and thus the
accompanying checksum must be changed from
3f40d7994397109285ec7b81fdeb3b58 to
4d92cd373abda3937c2bc47fbc49d690.
A better alternative is to have
<filename>LIC_FILES_CHKSUM</filename> point to a file
describing the license that is distributed with the source
that the recipe is building, if possible, rather than pointing
to <filename>${COREBASE}/LICENSE</filename>.
</para>
</section>
<section id='migration-1.6-cflags-options'>
<title><filename>CFLAGS</filename> Options</title>
<para>
The "-fpermissive" option has been removed from the default
<link linkend='var-CFLAGS'><filename>CFLAGS</filename></link>
value.
You need to take action on individual recipes that fail when
building with this option.
You need to either patch the recipes to fix the issues reported by
the compiler, or you need to add "-fpermissive" to
<filename>CFLAGS</filename> in the recipes.
</para>
</section>
<section id='migration-1.6-custom-images'>
<title>Custom Image Output Types</title>
<para>
Custom image output types, as selected using
<link linkend='var-IMAGE_FSTYPES'><filename>IMAGE_FSTYPES</filename></link>,
must declare their dependencies on other image types (if any) using
a new
<link linkend='var-IMAGE_TYPEDEP'><filename>IMAGE_TYPEDEP</filename></link>
variable.
</para>
</section>
<section id='migration-1.6-do-package-write-task'>
<title>Tasks</title>
<para>
The <filename>do_package_write</filename> task has been removed.
The task is no longer needed.
</para>
</section>
<section id='migration-1.6-update-alternatives-provider'>
<title><filename>update-alternative</filename> Provider</title>
<para>
The default <filename>update-alternatives</filename> provider has
been changed from <filename>opkg</filename> to
<filename>opkg-utils</filename>.
This change resolves some troublesome circular dependencies.
The runtime package has also been renamed from
<filename>update-alternatives-cworth</filename>
to <filename>update-alternatives-opkg</filename>.
</para>
</section>
<section id='migration-1.6-virtclass-overrides'>
<title><filename>virtclass</filename> Overrides</title>
<para>
The <filename>virtclass</filename> overrides are now deprecated.
Use the equivalent class overrides instead (e.g.
<filename>virtclass-native</filename> becomes
<filename>class-native</filename>.)
</para>
</section>
<section id='migration-1.6-removed-renamed-recipes'>
<title>Removed and Renamed Recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para><filename>packagegroup-toolset-native</filename> -
This recipe is largely unused.
</para></listitem>
<listitem><para><filename>linux-yocto-3.8</filename> -
Support for the Linux yocto 3.8 kernel has been dropped.
Support for the 3.10 and 3.14 kernels have been added
with the <filename>linux-yocto-3.10</filename> and
<filename>linux-yocto-3.14</filename> recipes.
</para></listitem>
<listitem><para><filename>ocf-linux</filename> -
This recipe has been functionally replaced using
<filename>cryptodev-linux</filename>.
</para></listitem>
<listitem><para><filename>genext2fs</filename> -
<filename>genext2fs</filename> is no longer used by the
build system and is unmaintained upstream.
</para></listitem>
<listitem><para><filename>js</filename> -
This provided an ancient version of Mozilla's javascript
engine that is no longer needed.
</para></listitem>
<listitem><para><filename>zaurusd</filename> -
The recipe has been moved to the
<filename>meta-handheld</filename> layer.
</para></listitem>
<listitem><para><filename>eglibc 2.17</filename> -
Replaced by the <filename>eglibc 2.19</filename>
recipe.
</para></listitem>
<listitem><para><filename>gcc 4.7.2</filename> -
Replaced by the now stable
<filename>gcc 4.8.2</filename>.
</para></listitem>
<listitem><para><filename>external-sourcery-toolchain</filename> -
this recipe is now maintained in the
<filename>meta-sourcery</filename> layer.
</para></listitem>
<listitem><para><filename>linux-libc-headers-yocto 3.4+git</filename> -
Now using version 3.10 of the
<filename>linux-libc-headers</filename> by default.
</para></listitem>
<listitem><para><filename>meta-toolchain-gmae</filename> -
This recipe is obsolete.
</para></listitem>
<listitem><para><filename>packagegroup-core-sdk-gmae</filename> -
This recipe is obsolete.
</para></listitem>
<listitem><para><filename>packagegroup-core-standalone-gmae-sdk-target</filename> -
This recipe is obsolete.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.6-removed-classes'>
<title>Removed Classes</title>
<para>
The following classes have become obsolete and have been removed:
<itemizedlist>
<listitem><para><filename>module_strip</filename>
</para></listitem>
<listitem><para><filename>pkg_metainfo</filename>
</para></listitem>
<listitem><para><filename>pkg_distribute</filename>
</para></listitem>
<listitem><para><filename>image-empty</filename>
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.6-reference-bsps'>
<title>Reference Board Support Packages (BSPs)</title>
<para>
The following reference BSPs changes occurred:
<itemizedlist>
<listitem><para>The BeagleBoard
(<filename>beagleboard</filename>) ARM reference hardware
has been replaced by the BeagleBone
(<filename>beaglebone</filename>) hardware.
</para></listitem>
<listitem><para>The RouterStation Pro
(<filename>routerstationpro</filename>) MIPS reference
hardware has been replaced by the EdgeRouter Lite
(<filename>edgerouter</filename>) hardware.
</para></listitem>
</itemizedlist>
The previous reference BSPs for the
<filename>beagleboard</filename> and
<filename>routerstationpro</filename> machines are still available
in a new <filename>meta-yocto-bsp-old</filename> layer in the
<ulink url='&YOCTO_GIT_URL;'>Source Repositories</ulink>
at
<ulink url='http://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto-bsp-old/'>http://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto-bsp-old/</ulink>.
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-1.7-release'>
<title>Moving to the Yocto Project 1.7 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 1.7 Release from the prior release.
</para>
<section id='migration-1.7-changes-to-setting-qemu-packageconfig-options'>
<title>Changes to Setting QEMU <filename>PACKAGECONFIG</filename> Options in <filename>local.conf</filename></title>
<para>
The QEMU recipe now uses a number of
<link linkend='var-PACKAGECONFIG'><filename>PACKAGECONFIG</filename></link>
options to enable various optional features.
The method used to set defaults for these options means that
existing
<filename>local.conf</filename> files will need to be be
modified to append to <filename>PACKAGECONFIG</filename> for
<filename>qemu-native</filename> and
<filename>nativesdk-qemu</filename> instead of setting it.
In other words, to enable graphical output for QEMU, you should
now have these lines in <filename>local.conf</filename>:
<literallayout class='monospaced'>
PACKAGECONFIG_append_pn-qemu-native = " sdl"
PACKAGECONFIG_append_pn-nativesdk-qemu = " sdl"
</literallayout>
</para>
</section>
<section id='migration-1.7-minimum-git-version'>
<title>Minimum Git version</title>
<para>
The minimum
<ulink url='&YOCTO_DOCS_OM_URL;#git'>Git</ulink> version
required on the build host is now 1.7.8 because the
<filename>--list</filename> option is now required by
BitBake's Git fetcher.
As always, if your host distribution does not provide a version of
Git that meets this requirement, you can use the
<filename>buildtools-tarball</filename> that does.
See the
"<link linkend='required-git-tar-python-and-gcc-versions'>Required Git, tar, Python and gcc Versions</link>"
section for more information.
</para>
</section>
<section id='migration-1.7-autotools-class-changes'>
<title>Autotools Class Changes</title>
<para>
The following
<link linkend='ref-classes-autotools'><filename>autotools</filename></link>
class changes occurred:
<itemizedlist>
<listitem><para><emphasis>
A separate build directory is now used by default:</emphasis>
The <filename>autotools</filename> class has been changed
to use a directory for building
(<link linkend='var-B'><filename>B</filename></link>),
which is separate from the source directory
(<link linkend='var-S'><filename>S</filename></link>).
This is commonly referred to as
<filename>B != S</filename>, or an out-of-tree build.</para>
<para>If the software being built is already capable of
building in a directory separate from the source, you
do not need to do anything.
However, if the software is not capable of being built
in this manner, you will
need to either patch the software so that it can build
separately, or you will need to change the recipe to
inherit the
<link linkend='ref-classes-autotools'><filename>autotools-brokensep</filename></link>
class instead of the <filename>autotools</filename> or
<filename>autotools_stage</filename> classes.
</para></listitem>
<listitem><para><emphasis>
The <filename>--foreign</filename> option is
no longer passed to <filename>automake</filename> when
running <filename>autoconf</filename>:</emphasis>
This option tells <filename>automake</filename> that a
particular software package does not follow the GNU
standards and therefore should not be expected
to distribute certain files such as
<filename>ChangeLog</filename>,
<filename>AUTHORS</filename>, and so forth.
Because the majority of upstream software packages already
tell <filename>automake</filename> to enable foreign mode
themselves, the option is mostly superfluous.
However, some recipes will need patches for this change.
You can easily make the change by patching
<filename>configure.ac</filename> so that it passes
"foreign" to <filename>AM_INIT_AUTOMAKE()</filename>.
See
<ulink url='http://cgit.openembedded.org/openembedded-core/commit/?id=01943188f85ce6411717fb5bf702d609f55813f2'>this commit</ulink>
for an example showing how to make the patch.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.7-binary-configuration-scripts-disabled'>
<title>Binary Configuration Scripts Disabled</title>
<para>
Some of the core recipes that package binary configuration scripts
now disable the scripts due to the
scripts previously requiring error-prone path substitution.
Software that links against these libraries using these scripts
should use the much more robust <filename>pkg-config</filename>
instead.
The list of recipes changed in this version (and their
configuration scripts) is as follows:
<literallayout class='monospaced'>
directfb (directfb-config)
freetype (freetype-config)
gpgme (gpgme-config)
libassuan (libassuan-config)
libcroco (croco-6.0-config)
libgcrypt (libgcrypt-config)
libgpg-error (gpg-error-config)
libksba (ksba-config)
libpcap (pcap-config)
libpcre (pcre-config)
libpng (libpng-config, libpng16-config)
libsdl (sdl-config)
libusb-compat (libusb-config)
libxml2 (xml2-config)
libxslt (xslt-config)
ncurses (ncurses-config)
neon (neon-config)
npth (npth-config)
pth (pth-config)
taglib (taglib-config)
</literallayout>
Additionally, support for <filename>pkg-config</filename> has been
added to some recipes in the previous list in the rare cases
where the upstream software package does not already provide
it.
</para>
</section>
<section id='migration-1.7-glibc-replaces-eglibc'>
<title><filename>eglibc 2.19</filename> Replaced with <filename>glibc 2.20</filename></title>
<para>
Because <filename>eglibc</filename> and
<filename>glibc</filename> were already fairly close, this
replacement should not require any significant changes to other
software that links to <filename>eglibc</filename>.
However, there were a number of minor changes in
<filename>glibc 2.20</filename> upstream that could require
patching some software (e.g. the removal of the
<filename>_BSD_SOURCE</filename> feature test macro).
</para>
<para>
<filename>glibc 2.20</filename> requires version 2.6.32 or greater
of the Linux kernel.
Thus, older kernels will no longer be usable in conjunction with it.
</para>
<para>
For full details on the changes in <filename>glibc 2.20</filename>,
see the upstream release notes
<ulink url='https://sourceware.org/ml/libc-alpha/2014-09/msg00088.html'>here</ulink>.
</para>
</section>
<section id='migration-1.7-kernel-module-autoloading'>
<title>Kernel Module Autoloading</title>
<para>
The
<link linkend='var-module_autoload'><filename>module_autoload_*</filename></link>
variable is now deprecated and a new
<link linkend='var-KERNEL_MODULE_AUTOLOAD'><filename>KERNEL_MODULE_AUTOLOAD</filename></link>
variable should be used instead.
Also,
<link linkend='var-module_conf'><filename>module_conf_*</filename></link>
must now be used in conjunction with a new
<link linkend='var-KERNEL_MODULE_PROBECONF'><filename>KERNEL_MODULE_PROBECONF</filename></link>
variable.
The new variables no longer require you to specify the module name
as part of the variable name.
This change not only simplifies usage but also allows the values
of these variables to be appropriately incorporated into task
signatures and thus trigger the appropriate tasks to re-execute
when changed.
You should replace any references to
<filename>module_autoload_*</filename> with
<filename>KERNEL_MODULE_AUTOLOAD</filename>, and add any modules
for which <filename>module_conf_*</filename> is specified to
<filename>KERNEL_MODULE_PROBECONF</filename>.
</para>
</section>
<section id='migration-1.7-qa-check-changes'>
<title>QA Check Changes</title>
<para>
The following changes have occurred to the QA check process:
<itemizedlist>
<listitem><para>
Additional QA checks <filename>file-rdeps</filename>
and <filename>build-deps</filename> have been added in
order to verify that file dependencies are satisfied
(e.g. package contains a script requiring
<filename>/bin/bash</filename>) and build-time dependencies
are declared, respectively.
For more information, please see the
"<link linkend='ref-qa-checks'>QA Error and Warning Messages</link>"
chapter.
</para></listitem>
<listitem><para>
Package QA checks are now performed during a new
<link linkend='ref-tasks-package_qa'><filename>do_package_qa</filename></link>
task rather than being part of the
<link linkend='ref-tasks-package'><filename>do_package</filename></link>
task.
This allows more parallel execution.
This change is unlikely to be an issue except for highly
customized recipes that disable packaging tasks themselves
by marking them as <filename>noexec</filename>.
For those packages, you will need to disable the
<filename>do_package_qa</filename> task as well.
</para></listitem>
<listitem><para>
Files being overwritten during the
<link linkend='ref-tasks-populate_sysroot'><filename>do_populate_sysroot</filename></link>
task now trigger an error instead of a warning.
Recipes should not be overwriting files written to the
sysroot by other recipes.
If you have these types of recipes, you need to alter them
so that they do not overwrite these files.</para>
<para>You might now receive this error after changes in
configuration or metadata resulting in orphaned files
being left in the sysroot.
If you do receive this error, the way to resolve the issue
is to delete your
<link linkend='var-TMPDIR'><filename>TMPDIR</filename></link>
or to move it out of the way and then re-start the build.
Anything that has been fully built up to that point and
does not need rebuilding will be restored from the shared
state cache and the rest of the build will be able to
proceed as normal.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.7-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para>
<filename>x-load</filename>:
This recipe has been superseded by
U-boot SPL for all Cortex-based TI SoCs.
For legacy boards, the <filename>meta-ti</filename>
layer, which contains a maintained recipe, should be used
instead.
</para></listitem>
<listitem><para>
<filename>ubootchart</filename>:
This recipe is obsolete.
A <filename>bootchart2</filename> recipe has been added
to functionally replace it.
</para></listitem>
<listitem><para>
<filename>linux-yocto 3.4</filename>:
Support for the linux-yocto 3.4 kernel has been dropped.
Support for the 3.10 and 3.14 kernels remains, while
support for version 3.17 has been added.
</para></listitem>
<listitem><para>
<filename>eglibc</filename> has been removed in favor of
<filename>glibc</filename>.
See the
"<link linkend='migration-1.7-glibc-replaces-eglibc'><filename>eglibc 2.19</filename> Replaced with <filename>glibc 2.20</filename></link>"
section for more information.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.7-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following miscellaneous change occurred:
<itemizedlist>
<listitem><para>
The build history feature now writes
<filename>build-id.txt</filename> instead of
<filename>build-id</filename>.
Additionally, <filename>build-id.txt</filename>
now contains the full build header as printed by
BitBake upon starting the build.
You should manually remove old "build-id" files from your
existing build history repositories to avoid confusion.
For information on the build history feature, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#maintaining-build-output-quality'>Maintaining Build Output Quality</ulink>"
section in the Yocto Project Development Tasks Manual.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-1.8-release'>
<title>Moving to the Yocto Project 1.8 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 1.8 Release from the prior release.
</para>
<section id='migration-1.8-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para><filename>owl-video</filename>:
Functionality replaced by <filename>gst-player</filename>.
</para></listitem>
<listitem><para><filename>gaku</filename>:
Functionality replaced by <filename>gst-player</filename>.
</para></listitem>
<listitem><para><filename>gnome-desktop</filename>:
This recipe is now available in
<filename>meta-gnome</filename> and is no longer needed.
</para></listitem>
<listitem><para><filename>gsettings-desktop-schemas</filename>:
This recipe is now available in
<filename>meta-gnome</filename> and is no longer needed.
</para></listitem>
<listitem><para><filename>python-argparse</filename>:
The <filename>argparse</filename> module is already
provided in the default Python distribution in a
package named <filename>python-argparse</filename>.
Consequently, the separate
<filename>python-argparse</filename> recipe is no
longer needed.
</para></listitem>
<listitem><para><filename>telepathy-python, libtelepathy, telepathy-glib, telepathy-idle, telepathy-mission-control</filename>:
All these recipes have moved to
<filename>meta-oe</filename> and are consequently no
longer needed by any recipes in OpenEmbedded-Core.
</para></listitem>
<listitem><para><filename>linux-yocto_3.10</filename> and <filename>linux-yocto_3.17</filename>:
Support for the linux-yocto 3.10 and 3.17 kernels has been
dropped.
Support for the 3.14 kernel remains, while support for
3.19 kernel has been added.
</para></listitem>
<listitem><para><filename>poky-feed-config-opkg</filename>:
This recipe has become obsolete and is no longer needed.
Use <filename>distro-feed-config</filename> from
<filename>meta-oe</filename> instead.
</para></listitem>
<listitem><para><filename>libav 0.8.x</filename>:
<filename>libav 9.x</filename> is now used.
</para></listitem>
<listitem><para><filename>sed-native</filename>:
No longer needed.
A working version of <filename>sed</filename> is expected
to be provided by the host distribution.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.8-bluez'>
<title>BlueZ 4.x / 5.x Selection</title>
<para>
Proper built-in support for selecting BlueZ 5.x in preference
to the default of 4.x now exists.
To use BlueZ 5.x, simply add "bluez5" to your
<link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link>
value.
If you had previously added append files
(<filename>*.bbappend</filename>) to make this selection, you can
now remove them.
</para>
<para>
Additionally, a <filename>bluetooth</filename> class has been added
to make selection of the appropriate bluetooth support within a
recipe a little easier.
If you wish to make use of this class in a recipe, add something
such as the following:
<literallayout class='monospaced'>
inherit bluetooth
PACKAGECONFIG ??= "${@bb.utils.contains('DISTRO_FEATURES', 'bluetooth', '${BLUEZ}', '', d)}"
PACKAGECONFIG[bluez4] = "--enable-bluetooth,--disable-bluetooth,bluez4"
PACKAGECONFIG[bluez5] = "--enable-bluez5,--disable-bluez5,bluez5"
</literallayout>
</para>
</section>
<section id='migration-1.8-kernel-build-changes'>
<title>Kernel Build Changes</title>
<para>
The kernel build process was changed to place the source
in a common shared work area and to place build artifacts
separately in the source code tree.
In theory, migration paths have been provided for most common
usages in kernel recipes but this might not work in all cases.
In particular, users need to ensure that
<filename>${S}</filename> (source files) and
<filename>${B}</filename> (build artifacts) are used
correctly in functions such as
<link linkend='ref-tasks-configure'><filename>do_configure</filename></link>
and
<link linkend='ref-tasks-install'><filename>do_install</filename></link>.
For kernel recipes that do not inherit from
<filename>kernel-yocto</filename> or include
<filename>linux-yocto.inc</filename>, you might wish to
refer to the <filename>linux.inc</filename> file in the
<filename>meta-oe</filename> layer for the kinds of changes you
need to make.
For reference, here is the
<ulink url='http://cgit.openembedded.org/meta-openembedded/commit/meta-oe/recipes-kernel/linux/linux.inc?id=fc7132ede27ac67669448d3d2845ce7d46c6a1ee'>commit</ulink>
where the <filename>linux.inc</filename> file in
<filename>meta-oe</filename> was updated.
</para>
<para>
Recipes that rely on the kernel source code and do not inherit
the module classes might need to add explicit dependencies on
the <filename>do_shared_workdir</filename> kernel task, for example:
<literallayout class='monospaced'>
do_configure[depends] += "virtual/kernel:do_shared_workdir"
</literallayout>
</para>
</section>
<section id='migration-1.8-ssl'>
<title>SSL 3.0 is Now Disabled in OpenSSL</title>
<para>
SSL 3.0 is now disabled when building OpenSSL.
Disabling SSL 3.0 avoids any lingering instances of the POODLE
vulnerability.
If you feel you must re-enable SSL 3.0, then you can add an
append file (<filename>*.bbappend</filename>) for the
<filename>openssl</filename> recipe to remove "-no-ssl3"
from
<link linkend='var-EXTRA_OECONF'><filename>EXTRA_OECONF</filename></link>.
</para>
</section>
<section id='migration-1.8-default-sysroot-poisoning'>
<title>Default Sysroot Poisoning</title>
<para>
<filename>gcc's</filename> default sysroot and include directories
are now "poisoned".
In other words, the sysroot and include directories are being
redirected to a non-existent location in order to catch when
host directories are being used due to the correct options not
being passed.
This poisoning applies both to the cross-compiler used within the
build and to the cross-compiler produced in the SDK.
</para>
<para>
If this change causes something in the build to fail, it almost
certainly means the various compiler flags and commands are not
being passed correctly to the underlying piece of software.
In such cases, you need to take corrective steps.
</para>
</section>
<section id='migration-1.8-rebuild-improvements'>
<title>Rebuild Improvements</title>
<para>
Changes have been made to the
<link linkend='ref-classes-base'><filename>base</filename></link>,
<link linkend='ref-classes-autotools'><filename>autotools</filename></link>,
and
<link linkend='ref-classes-cmake'><filename>cmake</filename></link>
classes to clean out generated files when the
<link linkend='ref-tasks-configure'><filename>do_configure</filename></link>
task needs to be re-executed.
</para>
<para>
One of the improvements is to attempt to run "make clean" during
the <filename>do_configure</filename> task if a
<filename>Makefile</filename> exists.
Some software packages do not provide a working clean target
within their make files.
If you have such recipes, you need to set
<link linkend='var-CLEANBROKEN'><filename>CLEANBROKEN</filename></link>
to "1" within the recipe, for example:
<literallayout class='monospaced'>
CLEANBROKEN = "1"
</literallayout>
</para>
</section>
<section id='migration-1.8-qa-check-and-validation-changes'>
<title>QA Check and Validation Changes</title>
<para>
The following QA Check and Validation Changes have occurred:
<itemizedlist>
<listitem><para>
Usage of <filename>PRINC</filename>
previously triggered a warning.
It now triggers an error.
You should remove any remaining usage of
<filename>PRINC</filename> in any recipe or append file.
</para></listitem>
<listitem><para>
An additional QA check has been added to detect usage of
<filename>${D}</filename> in
<link linkend='var-FILES'><filename>FILES</filename></link>
values where
<link linkend='var-D'><filename>D</filename></link> values
should not be used at all.
The same check ensures that <filename>$D</filename> is used
in
<filename>pkg_preinst/pkg_postinst/pkg_prerm/pkg_postrm</filename>
functions instead of <filename>${D}</filename>.
</para></listitem>
<listitem><para>
<link linkend='var-S'><filename>S</filename></link> now
needs to be set to a valid value within a recipe.
If <filename>S</filename> is not set in the recipe, the
directory is not automatically created.
If <filename>S</filename> does not point to a directory
that exists at the time the
<link linkend='ref-tasks-unpack'><filename>do_unpack</filename></link>
task finishes, a warning will be shown.
</para></listitem>
<listitem><para>
<link linkend='var-LICENSE'><filename>LICENSE</filename></link>
is now validated for correct formatting of multiple
licenses.
If the format is invalid (e.g. multiple licenses are
specified with no operators to specify how the multiple
licenses interact), then a warning will be shown.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-1.8-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following miscellaneous changes have occurred:
<itemizedlist>
<listitem><para>
The <filename>send-error-report</filename> script now
expects a "-s" option to be specified before the server
address.
This assumes a server address is being specified.
</para></listitem>
<listitem><para>
The <filename>oe-pkgdata-util</filename> script now
expects a "-p" option to be specified before the
<filename>pkgdata</filename> directory, which is now
optional.
If the <filename>pkgdata</filename> directory is not
specified, the script will run BitBake to query
<link linkend='var-PKGDATA_DIR'><filename>PKGDATA_DIR</filename></link>
from the build environment.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.0-release'>
<title>Moving to the Yocto Project 2.0 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.0 Release from the prior release.
</para>
<section id='migration-2.0-gcc-5'>
<title>GCC 5</title>
<para>
The default compiler is now GCC 5.2.
This change has required fixes for compilation errors in a number
of other recipes.
</para>
<para>
One important example is a fix for when the Linux kernel freezes at
boot time on ARM when built with GCC 5.
If you are using your own kernel recipe or source tree and
building for ARM, you will likely need to apply this
<ulink url='https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit?id=a077224fd35b2f7fbc93f14cf67074fc792fbac2'>patch</ulink>.
The standard <filename>linux-yocto</filename> kernel source tree
already has a workaround for the same issue.
</para>
<para>
For further details, see
<ulink url='https://gcc.gnu.org/gcc-5/changes.html'></ulink> and
the porting guide at
<ulink url='https://gcc.gnu.org/gcc-5/porting_to.html'></ulink>.
</para>
<para>
Alternatively, you can switch back to GCC 4.9 or 4.8 by
setting <filename>GCCVERSION</filename> in your configuration,
as follows:
<literallayout class='monospaced'>
GCCVERSION = "4.9%"
</literallayout>
</para>
</section>
<section id='migration-2.0-Gstreamer-0.10-removed'>
<title>Gstreamer 0.10 Removed</title>
<para>
Gstreamer 0.10 has been removed in favor of Gstreamer 1.x.
As part of the change, recipes for Gstreamer 0.10 and related
software are now located
in <filename>meta-multimedia</filename>.
This change results in Qt4 having Phonon and Gstreamer
support in QtWebkit disabled by default.
</para>
</section>
<section id='migration-2.0-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been moved or removed:
<itemizedlist>
<listitem><para>
<filename>bluez4</filename>: The recipe is obsolete and
has been moved due to <filename>bluez5</filename>
becoming fully integrated.
The <filename>bluez4</filename> recipe now resides in
<filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>gamin</filename>: The recipe is obsolete and
has been removed.
</para></listitem>
<listitem><para>
<filename>gnome-icon-theme</filename>: The recipe's
functionally has been replaced by
<filename>adwaita-icon-theme</filename>.
</para></listitem>
<listitem><para>
Gstreamer 0.10 Recipes: Recipes for Gstreamer 0.10 have
been removed in favor of the recipes for Gstreamer 1.x.
</para></listitem>
<listitem><para>
<filename>insserv</filename>: The recipe is obsolete and
has been removed.
</para></listitem>
<listitem><para>
<filename>libunique</filename>: The recipe is no longer
used and has been moved to <filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>midori</filename>: The recipe's functionally
has been replaced by <filename>epiphany</filename>.
</para></listitem>
<listitem><para>
<filename>python-gst</filename>: The recipe is obsolete
and has been removed since it only contains bindings for
Gstreamer 0.10.
</para></listitem>
<listitem><para>
<filename>qt-mobility</filename>: The recipe is obsolete and
has been removed since it requires
<filename>Gstreamer 0.10</filename>, which has been
replaced.
</para></listitem>
<listitem><para>
<filename>subversion</filename>: All 1.6.x versions of this
recipe have been removed.
</para></listitem>
<listitem><para>
<filename>webkit-gtk</filename>: The older 1.8.3 version
of this recipe has been removed in favor of
<filename>webkitgtk</filename>.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.0-bitbake-datastore-improvements'>
<title>BitBake datastore improvements</title>
<para>
The method by which BitBake's datastore handles overrides has
changed.
Overrides are now applied dynamically and
<filename>bb.data.update_data()</filename> is now a no-op.
Thus, <filename>bb.data.update_data()</filename> is no longer
required in order to apply the correct overrides.
In practice, this change is unlikely to require any changes to
Metadata.
However, these minor changes in behavior exist:
<itemizedlist>
<listitem><para>
All potential overrides are now visible in the variable
history as seen when you run the following:
<literallayout class='monospaced'>
$ bitbake -e
</literallayout>
</para></listitem>
<listitem><para>
<filename>d.delVar('</filename><replaceable>VARNAME</replaceable><filename>')</filename> and
<filename>d.setVar('</filename><replaceable>VARNAME</replaceable><filename>', None)</filename>
result in the variable and all of its overrides being
cleared out.
Before the change, only the non-overridden values
were cleared.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.0-shell-message-function-changes'>
<title>Shell Message Function Changes</title>
<para>
The shell versions of the BitBake message functions (i.e.
<filename>bbdebug</filename>, <filename>bbnote</filename>,
<filename>bbwarn</filename>, <filename>bbplain</filename>,
<filename>bberror</filename>, and <filename>bbfatal</filename>)
are now connected through to their BitBake equivalents
<filename>bb.debug()</filename>, <filename>bb.note()</filename>,
<filename>bb.warn()</filename>, <filename>bb.plain()</filename>,
<filename>bb.error()</filename>, and
<filename>bb.fatal()</filename>, respectively.
Thus, those message functions that you would expect to be printed
by the BitBake UI are now actually printed.
In practice, this change means two things:
<itemizedlist>
<listitem><para>
If you now see messages on the console that you did not
previously see as a result of this change, you might
need to clean up the calls to
<filename>bbwarn</filename>, <filename>bberror</filename>,
and so forth.
Or, you might want to simply remove the calls.
</para></listitem>
<listitem><para>
The <filename>bbfatal</filename> message function now
suppresses the full error log in the UI, which means any
calls to <filename>bbfatal</filename> where you still
wish to see the full error log should be replaced by
<filename>die</filename> or
<filename>bbfatal_log</filename>.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.0-extra-development-debug-package-cleanup'>
<title>Extra Development/Debug Package Cleanup</title>
<para>
The following recipes have had extra
<filename>dev/dbg</filename> packages removed:
<itemizedlist>
<listitem><para>
<filename>acl</filename>
</para></listitem>
<listitem><para>
<filename>apmd</filename>
</para></listitem>
<listitem><para>
<filename>aspell</filename>
</para></listitem>
<listitem><para>
<filename>attr</filename>
</para></listitem>
<listitem><para>
<filename>augeas</filename>
</para></listitem>
<listitem><para>
<filename>bzip2</filename>
</para></listitem>
<listitem><para>
<filename>cogl</filename>
</para></listitem>
<listitem><para>
<filename>curl</filename>
</para></listitem>
<listitem><para>
<filename>elfutils</filename>
</para></listitem>
<listitem><para>
<filename>gcc-target</filename>
</para></listitem>
<listitem><para>
<filename>libgcc</filename>
</para></listitem>
<listitem><para>
<filename>libtool</filename>
</para></listitem>
<listitem><para>
<filename>libxmu</filename>
</para></listitem>
<listitem><para>
<filename>opkg</filename>
</para></listitem>
<listitem><para>
<filename>pciutils</filename>
</para></listitem>
<listitem><para>
<filename>rpm</filename>
</para></listitem>
<listitem><para>
<filename>sysfsutils</filename>
</para></listitem>
<listitem><para>
<filename>tiff</filename>
</para></listitem>
<listitem><para>
<filename>xz</filename>
</para></listitem>
</itemizedlist>
All of the above recipes now conform to the standard packaging
scheme where a single <filename>-dev</filename>,
<filename>-dbg</filename>, and <filename>-staticdev</filename>
package exists per recipe.
</para>
</section>
<section id='migration-2.0-recipe-maintenance-tracking-data-moved-to-oe-core'>
<title>Recipe Maintenance Tracking Data Moved to OE-Core</title>
<para>
Maintenance tracking data for recipes that was previously part
of <filename>meta-yocto</filename> has been moved to
<link linkend='oe-core'>OE-Core</link>.
The change includes <filename>package_regex.inc</filename> and
<filename>distro_alias.inc</filename>, which are typically enabled
when using the <filename>distrodata</filename> class.
Additionally, the contents of
<filename>upstream_tracking.inc</filename> has now been split out
to the relevant recipes.
</para>
</section>
<section id='migration-2.0-automatic-stale-sysroot-file-cleanup'>
<title>Automatic Stale Sysroot File Cleanup</title>
<para>
Stale files from recipes that no longer exist in the current
configuration are now automatically removed from
sysroot as well as removed from
any other place managed by shared state.
This automatic cleanup means that the build system now properly
handles situations such as renaming the build system side of
recipes, removal of layers from
<filename>bblayers.conf</filename>, and
<link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link>
changes.
</para>
<para>
Additionally, work directories for old versions of recipes are
now pruned.
If you wish to disable pruning old work directories, you can set
the following variable in your configuration:
<literallayout class='monospaced'>
SSTATE_PRUNE_OBSOLETEWORKDIR = "0"
</literallayout>
</para>
</section>
<section id='migration-2.0-linux-yocto-kernel-metadata-repository-now-split-from-source'>
<title><filename>linux-yocto</filename> Kernel Metadata Repository Now Split from Source</title>
<para>
The <filename>linux-yocto</filename> tree has up to now been a
combined set of kernel changes and configuration (meta) data
carried in a single tree.
While this format is effective at keeping kernel configuration and
source modifications synchronized, it is not always obvious to
developers how to manipulate the Metadata as compared to the
source.
</para>
<para>
Metadata processing has now been removed from the
<link linkend='ref-classes-kernel-yocto'><filename>kernel-yocto</filename></link>
class and the external Metadata repository
<filename>yocto-kernel-cache</filename>, which has always been used
to seed the <filename>linux-yocto</filename> "meta" branch.
This separate <filename>linux-yocto</filename> cache repository
is now the primary location for this data.
Due to this change, <filename>linux-yocto</filename> is no longer
able to process combined trees.
Thus, if you need to have your own combined kernel repository,
you must do the split there as well and update your recipes
accordingly.
See the <filename>meta/recipes-kernel/linux/linux-yocto_4.1.bb</filename>
recipe for an example.
</para>
</section>
<section id='migration-2.0-additional-qa-checks'>
<title>Additional QA checks</title>
<para>
The following QA checks have been added:
<itemizedlist>
<listitem><para>
Added a "host-user-contaminated" check for ownership
issues for packaged files outside of
<filename>/home</filename>.
The check looks for files that are incorrectly owned by the
user that ran BitBake instead of owned by a valid user in
the target system.
</para></listitem>
<listitem><para>
Added an "invalid-chars" check for invalid (non-UTF8)
characters in recipe metadata variable values
(i.e.
<link linkend='var-DESCRIPTION'><filename>DESCRIPTION</filename></link>,
<link linkend='var-SUMMARY'><filename>SUMMARY</filename></link>,
<link linkend='var-LICENSE'><filename>LICENSE</filename></link>,
and
<link linkend='var-SECTION'><filename>SECTION</filename></link>).
Some package managers do not support these characters.
</para></listitem>
<listitem><para>
Added an "invalid-packageconfig" check for any options
specified in
<link linkend='var-PACKAGECONFIG'><filename>PACKAGECONFIG</filename></link>
that do not match any <filename>PACKAGECONFIG</filename>
option defined for the recipe.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.0-miscellaneous'>
<title>Miscellaneous Changes</title>
<para>
These additional changes exist:
<itemizedlist>
<listitem><para>
<filename>gtk-update-icon-cache</filename> has been
renamed to <filename>gtk-icon-utils</filename>.
</para></listitem>
<listitem><para>
The <filename>tools-profile</filename>
<link linkend='var-IMAGE_FEATURES'><filename>IMAGE_FEATURES</filename></link>
item as well as its corresponding packagegroup and
<filename>packagegroup-core-tools-profile</filename> no
longer bring in <filename>oprofile</filename>.
Bringing in <filename>oprofile</filename> was originally
added to aid compilation on resource-constrained
targets.
However, this aid has not been widely used and is not
likely to be used going forward due to the more powerful
target platforms and the existence of better
cross-compilation tools.
</para></listitem>
<listitem><para>
The
<link linkend='var-IMAGE_FSTYPES'><filename>IMAGE_FSTYPES</filename></link>
variable's default value now specifies
<filename>ext4</filename> instead of
<filename>ext3</filename>.
</para></listitem>
<listitem><para>
All support for the <filename>PRINC</filename>
variable has been removed.
</para></listitem>
<listitem><para>
The <filename>packagegroup-core-full-cmdline</filename>
packagegroup no longer brings in
<filename>lighttpd</filename> due to the fact that
bringing in <filename>lighttpd</filename> is not really in
line with the packagegroup's purpose, which is to add full
versions of command-line tools that by default are
provided by <filename>busybox</filename>.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.1-release'>
<title>Moving to the Yocto Project 2.1 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.1 Release from the prior release.
</para>
<section id='migration-2.1-variable-expansion-in-python-functions'>
<title>Variable Expansion in Python Functions</title>
<para>
Variable expressions, such as
<filename>${</filename><replaceable>VARNAME</replaceable><filename>}</filename>
no longer expand automatically within Python functions.
Suppressing expansion was done to allow Python functions to
construct shell scripts or other code for situations in which you
do not want such expressions expanded.
For any existing code that relies on these expansions, you need to
change the expansions to expand the value of individual
variables through <filename>d.getVar()</filename>.
To alternatively expand more complex expressions,
use <filename>d.expand()</filename>.
</para>
</section>
<section id='migration-2.1-overrides-must-now-be-lower-case'>
<title>Overrides Must Now be Lower-Case</title>
<para>
The convention for overrides has always been for them to be
lower-case characters.
This practice is now a requirement as BitBake's datastore now
assumes lower-case characters in order to give a slight performance
boost during parsing.
In practical terms, this requirement means that anything that ends
up in
<link linkend='var-OVERRIDES'><filename>OVERRIDES</filename></link>
must now appear in lower-case characters (e.g. values for
<filename>MACHINE</filename>, <filename>TARGET_ARCH</filename>,
<filename>DISTRO</filename>, and also recipe names if
<filename>_pn-</filename><replaceable>recipename</replaceable>
overrides are to be effective).
</para>
</section>
<section id='migration-2.1-expand-parameter-to-getvar-and-getvarflag-now-mandatory'>
<title>Expand Parameter to <filename>getVar()</filename> and
<filename>getVarFlag()</filename> is Now Mandatory</title>
<para>
The expand parameter to <filename>getVar()</filename> and
<filename>getVarFlag()</filename> previously defaulted to
False if not specified.
Now, however, no default exists so one must be specified.
You must change any <filename>getVar()</filename> calls that
do not specify the final expand parameter to calls that do specify
the parameter.
You can run the following <filename>sed</filename> command at the
base of a layer to make this change:
<literallayout class='monospaced'>
sed -e 's:\(\.getVar([^,()]*\)):\1, False):g' -i `grep -ril getVar *`
sed -e 's:\(\.getVarFlag([^,()]*, [^,()]*\)):\1, False):g' -i `grep -ril getVarFlag *`
</literallayout>
<note>
The reason for this change is that it prepares the way for
changing the default to True in a future Yocto Project release.
This future change is a much more sensible default than False.
However, the change needs to be made gradually as a sudden
change of the default would potentially cause side-effects
that would be difficult to detect.
</note>
</para>
</section>
<section id='migration-2.1-makefile-environment-changes'>
<title>Makefile Environment Changes</title>
<para>
<link linkend='var-EXTRA_OEMAKE'><filename>EXTRA_OEMAKE</filename></link>
now defaults to "" instead of "-e MAKEFLAGS=".
Setting <filename>EXTRA_OEMAKE</filename> to "-e MAKEFLAGS=" by
default was a historical accident that has required many classes
(e.g. <filename>autotools</filename>, <filename>module</filename>)
and recipes to override this default in order to work with
sensible build systems.
When upgrading to the release, you must edit any recipe that
relies upon this old default by either setting
<filename>EXTRA_OEMAKE</filename> back to "-e MAKEFLAGS=" or by
explicitly setting any required variable value overrides using
<filename>EXTRA_OEMAKE</filename>, which is typically only needed
when a Makefile sets a default value for a variable that is
inappropriate for cross-compilation using the "=" operator rather
than the "?=" operator.
</para>
</section>
<section id='migration-2.1-libexecdir-reverted-to-prefix-libexec'>
<title><filename>libexecdir</filename> Reverted to <filename>${prefix}/libexec</filename></title>
<para>
The use of <filename>${libdir}/${BPN}</filename> as
<filename>libexecdir</filename> is different as compared to all
other mainstream distributions, which either uses
<filename>${prefix}/libexec</filename> or
<filename>${libdir}</filename>.
The use is also contrary to the GNU Coding Standards
(i.e. <ulink url='https://www.gnu.org/prep/standards/html_node/Directory-Variables.html'></ulink>)
that suggest <filename>${prefix}/libexec</filename> and also
notes that any package-specific nesting should be done by the
package itself.
Finally, having <filename>libexecdir</filename> change between
recipes makes it very difficult for different recipes to invoke
binaries that have been installed into
<filename>libexecdir</filename>.
The Filesystem Hierarchy Standard
(i.e. <ulink url='http://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch04s07.html'></ulink>)
now recognizes the use of <filename>${prefix}/libexec/</filename>,
giving distributions the choice between
<filename>${prefix}/lib</filename> or
<filename>${prefix}/libexec</filename> without breaking FHS.
</para>
</section>
<section id='migration-2.1-ac-cv-sizeof-off-t-no-longer-cached-in-site-files'>
<title><filename>ac_cv_sizeof_off_t</filename> is No Longer Cached in Site Files</title>
<para>
For recipes inheriting the
<link linkend='ref-classes-autotools'><filename>autotools</filename></link>
class, <filename>ac_cv_sizeof_off_t</filename> is no longer cached
in the site files for <filename>autoconf</filename>.
The reason for this change is because the
<filename>ac_cv_sizeof_off_t</filename> value is not necessarily
static per architecture as was previously assumed.
Rather, the value changes based on whether large file support is
enabled.
For most software that uses <filename>autoconf</filename>, this
change should not be a problem.
However, if you have a recipe that bypasses the standard
<link linkend='ref-tasks-configure'><filename>do_configure</filename></link>
task from the <filename>autotools</filename> class and the software
the recipe is building uses a very old version of
<filename>autoconf</filename>, the recipe might be incapable of
determining the correct size of <filename>off_t</filename> during
<filename>do_configure</filename>.
</para>
<para>
The best course of action is to patch the software as necessary
to allow the default implementation from the
<filename>autotools</filename> class to work such that
<filename>autoreconf</filename> succeeds and produces a working
configure script, and to remove the
overridden <filename>do_configure</filename> task such that the
default implementation does get used.
</para>
</section>
<section id='migration-2.1-image-generation-split-out-from-filesystem-generation'>
<title>Image Generation is Now Split Out from Filesystem Generation</title>
<para>
Previously, for image recipes the
<link linkend='ref-tasks-rootfs'><filename>do_rootfs</filename></link>
task assembled the filesystem and then from that filesystem
generated images.
With this Yocto Project release, image generation is split into
separate
<link linkend='ref-tasks-image'><filename>do_image_*</filename></link>
tasks for clarity both in operation and in the code.
</para>
<para>
For most cases, this change does not present any problems.
However, if you have made customizations that directly modify the
<filename>do_rootfs</filename> task or that mention
<filename>do_rootfs</filename>, you might need to update those
changes.
In particular, if you had added any tasks after
<filename>do_rootfs</filename>, you should make edits so that
those tasks are after the
<link linkend='ref-tasks-image-complete'><filename>do_image_complete</filename></link>
task rather than after <filename>do_rootfs</filename>
so that the your added tasks
run at the correct time.
</para>
<para>
A minor part of this restructuring is that the post-processing
definitions and functions have been moved from the
<link linkend='ref-classes-image'><filename>image</filename></link>
class to the
<link linkend='ref-classes-rootfs*'><filename>rootfs-postcommands</filename></link>
class.
Functionally, however, they remain unchanged.
</para>
</section>
<section id='migration-2.1-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed in the 2.1 release:
<itemizedlist>
<listitem><para><filename>gcc</filename> version 4.8:
Versions 4.9 and 5.3 remain.
</para></listitem>
<listitem><para><filename>qt4</filename>:
All support for Qt 4.x has been moved out to a separate
<filename>meta-qt4</filename> layer because Qt 4 is no
longer supported upstream.
</para></listitem>
<listitem><para><filename>x11vnc</filename>:
Moved to the <filename>meta-oe</filename> layer.
</para></listitem>
<listitem><para><filename>linux-yocto-3.14</filename>:
No longer supported.
</para></listitem>
<listitem><para><filename>linux-yocto-3.19</filename>:
No longer supported.
</para></listitem>
<listitem><para><filename>libjpeg</filename>:
Replaced by the <filename>libjpeg-turbo</filename> recipe.
</para></listitem>
<listitem><para><filename>pth</filename>:
Became obsolete.
</para></listitem>
<listitem><para><filename>liboil</filename>:
Recipe is no longer needed and has been moved to the
<filename>meta-multimedia</filename> layer.
</para></listitem>
<listitem><para><filename>gtk-theme-torturer</filename>:
Recipe is no longer needed and has been moved to the
<filename>meta-gnome</filename> layer.
</para></listitem>
<listitem><para><filename>gnome-mime-data</filename>:
Recipe is no longer needed and has been moved to the
<filename>meta-gnome</filename> layer.
</para></listitem>
<listitem><para><filename>udev</filename>:
Replaced by the <filename>eudev</filename> recipe for
compatibility when using <filename>sysvinit</filename>
with newer kernels.
</para></listitem>
<listitem><para><filename>python-pygtk</filename>:
Recipe became obsolete.
</para></listitem>
<listitem><para><filename>adt-installer</filename>:
Recipe became obsolete.
See the
"<link linkend='migration-2.1-adt-removed'>ADT Removed</link>"
section for more information.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.1-class-changes'>
<title>Class Changes</title>
<para>
The following classes have changed:
<itemizedlist>
<listitem><para><filename>autotools_stage</filename>:
Removed because the
<link linkend='ref-classes-autotools'><filename>autotools</filename></link>
class now provides its functionality.
Recipes that inherited from
<filename>autotools_stage</filename> should now inherit
from <filename>autotools</filename> instead.
</para></listitem>
<listitem><para><filename>boot-directdisk</filename>:
Merged into the <filename>image-vm</filename>
class.
The <filename>boot-directdisk</filename> class was rarely
directly used.
Consequently, this change should not cause any issues.
</para></listitem>
<listitem><para><filename>bootimg</filename>:
Merged into the
<link linkend='ref-classes-image-live'><filename>image-live</filename></link>
class.
The <filename>bootimg</filename> class was rarely
directly used.
Consequently, this change should not cause any issues.
</para></listitem>
<listitem><para><filename>packageinfo</filename>:
Removed due to its limited use by the Hob UI, which has
itself been removed.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.1-build-system-ui-changes'>
<title>Build System User Interface Changes</title>
<para>
The following changes have been made to the build system user
interface:
<itemizedlist>
<listitem><para><emphasis>Hob GTK+-based UI</emphasis>:
Removed because it is unmaintained and based on the
outdated GTK+ 2 library.
The Toaster web-based UI is much more capable and is
actively maintained.
See the
"<ulink url='&YOCTO_DOCS_TOAST_URL;#using-the-toaster-web-interface'>Using the Toaster Web Interface</ulink>"
section in the Toaster User Manual for more
information on this interface.
</para></listitem>
<listitem><para><emphasis>"puccho" BitBake UI</emphasis>:
Removed because is unmaintained and no longer useful.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.1-adt-removed'>
<title>ADT Removed</title>
<para>
The Application Development Toolkit (ADT) has been removed
because its functionality almost completely overlapped with the
<ulink url='&YOCTO_DOCS_SDK_URL;#sdk-using-the-standard-sdk'>standard SDK</ulink>
and the
<ulink url='&YOCTO_DOCS_SDK_URL;#sdk-extensible'>extensible SDK</ulink>.
For information on these SDKs and how to build and use them, see the
<ulink url='&YOCTO_DOCS_SDK_URL;'>Yocto Project Application Development and the Extensible Software Development Kit (eSDK)</ulink>
manual.
<note>
The Yocto Project Eclipse IDE Plug-in is still supported and
is not affected by this change.
</note>
</para>
</section>
<section id='migration-2.1-poky-reference-distribution-changes'>
<title>Poky Reference Distribution Changes</title>
<para>
The following changes have been made for the Poky distribution:
<itemizedlist>
<listitem><para>
The <filename>meta-yocto</filename> layer has been renamed
to <filename>meta-poky</filename> to better match its
purpose, which is to provide the Poky reference
distribution.
The <filename>meta-yocto-bsp</filename> layer retains its
original name since it provides reference machines for
the Yocto Project and it is otherwise unrelated to Poky.
References to <filename>meta-yocto</filename> in your
<filename>conf/bblayers.conf</filename> should
automatically be updated, so you should not need to change
anything unless you are relying on this naming elsewhere.
</para></listitem>
<listitem><para>
The
<link linkend='ref-classes-uninative'><filename>uninative</filename></link>
class is now enabled by default in Poky.
This class attempts to isolate the build system from the
host distribution's C library and makes re-use of native
shared state artifacts across different host distributions
practical.
With this class enabled, a tarball containing a pre-built
C library is downloaded at the start of the build.</para>
<para>The <filename>uninative</filename> class is enabled
through the
<filename>meta/conf/distro/include/yocto-uninative.inc</filename>
file, which for those not using the Poky distribution, can
include to easily enable the same functionality.</para>
<para>Alternatively, if you wish to build your own
<filename>uninative</filename> tarball, you can do so by
building the <filename>uninative-tarball</filename> recipe,
making it available to your build machines
(e.g. over HTTP/HTTPS) and setting a similar configuration
as the one set by <filename>yocto-uninative.inc</filename>.
</para></listitem>
<listitem><para>
Static library generation, for most cases, is now disabled
by default in the Poky distribution.
Disabling this generation saves some build time as well
as the size used for build output artifacts.</para>
<para>Disabling this library generation is accomplished
through a
<filename>meta/conf/distro/include/no-static-libs.inc</filename>,
which for those not using the Poky distribution can
easily include to enable the same functionality.</para>
<para>Any recipe that needs to opt-out of having the
"--disable-static" option specified on the configure
command line either because it is not a supported option
for the configure script or because static libraries are
needed should set the following variable:
<literallayout class='monospaced'>
DISABLE_STATIC = ""
</literallayout>
</para></listitem>
<listitem><para>
The separate <filename>poky-tiny</filename> distribution
now uses the musl C library instead of a heavily pared
down <filename>glibc</filename>.
Using musl results in a smaller
distribution and facilitates much greater maintainability
because musl is designed to have a small footprint.</para>
<para>If you have used <filename>poky-tiny</filename> and
have customized the <filename>glibc</filename>
configuration you will need to redo those customizations
with musl when upgrading to the new release.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.1-packaging-changes'>
<title>Packaging Changes</title>
<para>
The following changes have been made to packaging:
<itemizedlist>
<listitem><para>
The <filename>runuser</filename> and
<filename>mountpoint</filename> binaries, which were
previously in the main <filename>util-linux</filename>
package, have been split out into the
<filename>util-linux-runuser</filename> and
<filename>util-linux-mountpoint</filename> packages,
respectively.
</para></listitem>
<listitem><para>
The <filename>python-elementtree</filename> package has
been merged into the <filename>python-xml</filename>
package.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.1-tuning-file-changes'>
<title>Tuning File Changes</title>
<para>
The following changes have been made to the tuning files:
<itemizedlist>
<listitem><para>
The "no-thumb-interwork" tuning feature has been dropped
from the ARM tune include files.
Because interworking is required for ARM EABI, attempting
to disable it through a tuning feature no longer makes
sense.
<note>
Support for ARM OABI was deprecated in gcc 4.7.
</note>
</para></listitem>
<listitem><para>
The <filename>tune-cortexm*.inc</filename> and
<filename>tune-cortexr4.inc</filename> files have been
removed because they are poorly tested.
Until the OpenEmbedded build system officially gains
support for CPUs without an MMU, these tuning files would
probably be better maintained in a separate layer
if needed.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.1-supporting-gobject-introspection'>
<title>Supporting GObject Introspection</title>
<para>
This release supports generation of GLib Introspective
Repository (GIR) files through GObject introspection, which is
the standard mechanism for accessing GObject-based software from
runtime environments.
You can enable, disable, and test the generation of this data.
See the
"<ulink url='&YOCTO_DOCS_DEV_URL;#enabling-gobject-introspection-support'>Enabling GObject Introspection Support</ulink>"
section in the Yocto Project Development Tasks Manual
for more information.
</para>
</section>
<section id='migration-2.1-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
These additional changes exist:
<itemizedlist>
<listitem><para>
The minimum Git version has been increased to 1.8.3.1.
If your host distribution does not provide a sufficiently
recent version, you can install the buildtools, which
will provide it.
See the
"<link linkend='required-git-tar-python-and-gcc-versions'>Required Git, tar, Python and gcc Versions</link>"
section for more information on the buildtools tarball.
</para></listitem>
<listitem><para>
The buggy and incomplete support for the RPM version 4
package manager has been removed.
The well-tested and maintained support for RPM version 5
remains.
</para></listitem>
<listitem><para>
Previously, the following list of packages were removed
if package-management was not in
<link linkend='var-IMAGE_FEATURES'><filename>IMAGE_FEATURES</filename></link>,
regardless of any dependencies:
<literallayout class='monospaced'>
update-rc.d
base-passwd
shadow
update-alternatives
run-postinsts
</literallayout>
With the Yocto Project 2.1 release, these packages are only
removed if "read-only-rootfs" is in
<filename>IMAGE_FEATURES</filename>, since they might
still be needed for a read-write image even in the absence
of a package manager (e.g. if users need to be added,
modified, or removed at runtime).
</para></listitem>
<listitem><para>
The
<ulink url='&YOCTO_DOCS_SDK_URL;#sdk-devtool-use-devtool-modify-to-modify-the-source-of-an-existing-component'><filename>devtool modify</filename></ulink>
command now defaults to extracting the source since that
is most commonly expected.
The "-x" or "--extract" options are now no-ops.
If you wish to provide your own existing source tree, you
will now need to specify either the "-n" or
"--no-extract" options when running
<filename>devtool modify</filename>.
</para></listitem>
<listitem><para>
If the formfactor for a machine is either not supplied
or does not specify whether a keyboard is attached, then
the default is to assume a keyboard is attached rather
than assume no keyboard.
This change primarily affects the Sato UI.
</para></listitem>
<listitem><para>
The <filename>.debug</filename> directory packaging is
now automatic.
If your recipe builds software that installs binaries into
directories other than the standard ones, you no longer
need to take care of setting
<filename>FILES_${PN}-dbg</filename> to pick up the
resulting <filename>.debug</filename> directories as these
directories are automatically found and added.
</para></listitem>
<listitem><para>
Inaccurate disk and CPU percentage data has been dropped
from <filename>buildstats</filename> output.
This data has been replaced with
<filename>getrusage()</filename> data and corrected IO
statistics.
You will probably need to update any custom code that reads
the <filename>buildstats</filename> data.
</para></listitem>
<listitem><para>
The
<filename>meta/conf/distro/include/package_regex.inc</filename>
is now deprecated.
The contents of this file have been moved to individual
recipes.
<note><title>Tip</title>
Because this file will likely be removed in a future
Yocto Project release, it is suggested that you remove
any references to the file that might be in your
configuration.
</note>
</para></listitem>
<listitem><para>
The <filename>v86d/uvesafb</filename> has been removed from
the <filename>genericx86</filename> and
<filename>genericx86-64</filename> reference machines,
which are provided by the
<filename>meta-yocto-bsp</filename> layer.
Most modern x86 boards do not rely on this file and it only
adds kernel error messages during startup.
If you do still need to support
<filename>uvesafb</filename>, you can
simply add <filename>v86d</filename> to your image.
</para></listitem>
<listitem><para>
Build sysroot paths are now removed from debug symbol
files.
Removing these paths means that remote GDB using an
unstripped build system sysroot will no longer work
(although this was never documented to work).
The supported method to accomplish something similar is
to set <filename>IMAGE_GEN_DEBUGFS</filename> to "1",
which will generate a companion debug image
containing unstripped binaries and associated debug
sources alongside the image.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.2-release'>
<title>Moving to the Yocto Project 2.2 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.2 Release from the prior release.
</para>
<section id='migration-2.2-minimum-kernel-version'>
<title>Minimum Kernel Version</title>
<para>
The minimum kernel version for the target system and for SDK
is now 3.2.0, due to the upgrade
to <filename>glibc 2.24</filename>.
Specifically, for AArch64-based targets the version is
3.14.
For Nios II-based targets, the minimum kernel version is 3.19.
<note>
For x86 and x86_64, you can reset
<link linkend='var-OLDEST_KERNEL'><filename>OLDEST_KERNEL</filename></link>
to anything down to 2.6.32 if desired.
</note>
</para>
</section>
<section id='migration-2.2-staging-directories-in-sysroot-simplified'>
<title>Staging Directories in Sysroot Has Been Simplified</title>
<para>
The way directories are staged in sysroot has been simplified and
introduces the new
<link linkend='var-SYSROOT_DIRS'><filename>SYSROOT_DIRS</filename></link>,
<link linkend='var-SYSROOT_DIRS_NATIVE'><filename>SYSROOT_DIRS_NATIVE</filename></link>,
and
<link linkend='var-SYSROOT_DIRS_BLACKLIST'><filename>SYSROOT_DIRS_BLACKLIST</filename></link>.
See the
<ulink url='http://lists.openembedded.org/pipermail/openembedded-core/2016-May/121365.html'>v2 patch series on the OE-Core Mailing List</ulink>
for additional information.
</para>
</section>
<section id='migration-2.2-removal-of-old-images-from-tmp-deploy-now-enabled'>
<title>Removal of Old Images and Other Files in <filename>tmp/deploy</filename> Now Enabled</title>
<para>
Removal of old images and other files in
<filename>tmp/deploy/</filename> is now enabled by default due
to a new staging method used for those files.
As a result of this change, the
<filename>RM_OLD_IMAGE</filename> variable is now redundant.
</para>
</section>
<section id='migration-2.2-python-changes'>
<title>Python Changes</title>
<para>
The following changes for Python occurred:
</para>
<section id='migration-2.2-bitbake-now-requires-python-3.4'>
<title>BitBake Now Requires Python 3.4+</title>
<para>
BitBake requires Python 3.4 or greater.
</para>
</section>
<section id='migration-2.2-utf-8-locale-required-on-build-host'>
<title>UTF-8 Locale Required on Build Host</title>
<para>
A UTF-8 locale is required on the build host due to Python 3.
Since C.UTF-8 is not a standard, the default is en_US.UTF-8.
</para>
</section>
<section id='migration-2.2-metadata-now-must-use-python-3-syntax'>
<title>Metadata Must Now Use Python 3 Syntax</title>
<para>
The metadata is now required to use Python 3 syntax.
For help preparing metadata, see any of the many Python 3 porting
guides available.
Alternatively, you can reference the conversion commits for Bitbake
and you can use
<link linkend='oe-core'>OE-Core</link> as a guide for changes.
Following are particular areas of interest:
<literallayout class='monospaced'>
* subprocess command-line pipes needing locale decoding
* the syntax for octal values changed
* the <filename>iter*()</filename> functions changed name
* iterators now return views, not lists
* changed names for Python modules
</literallayout>
</para>
</section>
<section id='migration-2.2-target-python-recipes-switched-to-python-3'>
<title>Target Python Recipes Switched to Python 3</title>
<para>
Most target Python recipes have now been switched to Python 3.
Unfortunately, systems using RPM as a package manager and
providing online package-manager support through SMART still
require Python 2.
<note>
Python 2 and recipes that use it can still be built for the
target as with previous versions.
</note>
</para>
</section>
<section id='migration-2.2-buildtools-tarball-includes-python-3'>
<title><filename>buildtools-tarball</filename> Includes Python 3</title>
<para>
<filename>buildtools-tarball</filename> now includes Python 3.
</para>
</section>
</section>
<section id='migration-2.2-uclibc-replaced-by-musl'>
<title>uClibc Replaced by musl</title>
<para>
uClibc has been removed in favor of musl.
Musl has matured, is better maintained, and is compatible with a
wider range of applications as compared to uClibc.
</para>
</section>
<section id='migration-2.2-B-no-longer-default-working-directory-for-tasks'>
<title><filename>${B}</filename> No Longer Default Working Directory for Tasks</title>
<para>
<filename>${</filename><link linkend='var-B'><filename>B</filename></link><filename>}</filename>
is no longer the default working directory for tasks.
Consequently, any custom tasks you define now need to either
have the
<filename>[</filename><ulink url='&YOCTO_DOCS_BB_URL;#variable-flags'><filename>dirs</filename></ulink><filename>]</filename> flag set, or the task needs to change into the
appropriate working directory manually (e.g using
<filename>cd</filename> for a shell task).
<note>
The preferred method is to use the
<filename>[dirs]</filename> flag.
</note>
</para>
</section>
<section id='migration-2.2-runqemu-ported-to-python'>
<title><filename>runqemu</filename> Ported to Python</title>
<para>
<filename>runqemu</filename> has been ported to Python and has
changed behavior in some cases.
Previous usage patterns continue to be supported.
</para>
<para>
The new <filename>runqemu</filename> is a Python script.
Machine knowledge is no longer hardcoded into
<filename>runqemu</filename>.
You can choose to use the <filename>qemuboot</filename>
configuration file to define the BSP's own arguments and to make
it bootable with <filename>runqemu</filename>.
If you use a configuration file, use the following form:
<literallayout class='monospaced'>
<replaceable>image-name</replaceable>-<replaceable>machine</replaceable>.qemuboot.conf
</literallayout>
The configuration file enables fine-grained tuning of options
passed to QEMU without the <filename>runqemu</filename> script
hard-coding any knowledge about different machines.
Using a configuration file is particularly convenient when trying
to use QEMU with machines other than the
<filename>qemu*</filename> machines in
<link linkend='oe-core'>OE-Core</link>.
The <filename>qemuboot.conf</filename> file is generated by the
<filename>qemuboot</filename>
class when the root filesystem is being build (i.e.
build rootfs).
QEMU boot arguments can be set in BSP's configuration file and
the <filename>qemuboot</filename> class will save them to
<filename>qemuboot.conf</filename>.
</para>
<para>
If you want to use <filename>runqemu</filename> without a
configuration file, use the following command form:
<literallayout class='monospaced'>
$ runqemu <replaceable>machine</replaceable> <replaceable>rootfs</replaceable> <replaceable>kernel</replaceable> [<replaceable>options</replaceable>]
</literallayout>
Supported <replaceable>machines</replaceable> are as follows:
<literallayout class='monospaced'>
qemuarm
qemuarm64
qemux86
qemux86-64
qemuppc
qemumips
qemumips64
qemumipsel
qemumips64el
</literallayout>
Consider the following example, which uses the
<filename>qemux86-64</filename> machine,
provides a root filesystem, provides an image, and uses
the <filename>nographic</filename> option:
<literallayout class='monospaced'>
$ runqemu qemux86-64 tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.ext4 tmp/deploy/images/qemux86-64/bzImage nographic
</literallayout>
</para>
<para>
Following is a list of variables that can be set in configuration
files such as <filename>bsp.conf</filename> to enable the BSP
to be booted by <filename>runqemu</filename>:
<note>
"QB" means "QEMU Boot".
</note>
<literallayout class='monospaced'>
QB_SYSTEM_NAME: QEMU name (e.g. "qemu-system-i386")
QB_OPT_APPEND: Options to append to QEMU (e.g. "-show-cursor")
QB_DEFAULT_KERNEL: Default kernel to boot (e.g. "bzImage")
QB_DEFAULT_FSTYPE: Default FSTYPE to boot (e.g. "ext4")
QB_MEM: Memory (e.g. "-m 512")
QB_MACHINE: QEMU machine (e.g. "-machine virt")
QB_CPU: QEMU cpu (e.g. "-cpu qemu32")
QB_CPU_KVM: Similar to QB_CPU except used for kvm support (e.g. "-cpu kvm64")
QB_KERNEL_CMDLINE_APPEND: Options to append to the kernel's -append
option (e.g. "console=ttyS0 console=tty")
QB_DTB: QEMU dtb name
QB_AUDIO_DRV: QEMU audio driver (e.g. "alsa", set it when support audio)
QB_AUDIO_OPT: QEMU audio option (e.g. "-soundhw ac97,es1370"), which is used
when QB_AUDIO_DRV is set.
QB_KERNEL_ROOT: Kernel's root (e.g. /dev/vda)
QB_TAP_OPT: Network option for 'tap' mode (e.g.
"-netdev tap,id=net0,ifname=@TAP@,script=no,downscript=no -device virtio-net-device,netdev=net0").
runqemu will replace "@TAP@" with the one that is used, such as tap0, tap1 ...
QB_SLIRP_OPT: Network option for SLIRP mode (e.g. "-netdev user,id=net0 -device virtio-net-device,netdev=net0")
QB_ROOTFS_OPT: Used as rootfs (e.g.
"-drive id=disk0,file=@ROOTFS@,if=none,format=raw -device virtio-blk-device,drive=disk0").
runqemu will replace "@ROOTFS@" with the one which is used, such as
core-image-minimal-qemuarm64.ext4.
QB_SERIAL_OPT: Serial port (e.g. "-serial mon:stdio")
QB_TCPSERIAL_OPT: tcp serial port option (e.g.
" -device virtio-serial-device -chardev socket,id=virtcon,port=@PORT@,host=127.0.0.1 -device virtconsole,chardev=virtcon"
runqemu will replace "@PORT@" with the port number which is used.
</literallayout>
</para>
<para>
To use <filename>runqemu</filename>, set
<link linkend='var-IMAGE_CLASSES'><filename>IMAGE_CLASSES</filename></link>
as follows and run <filename>runqemu</filename>:
<note>
For command-line syntax, use
<filename>runqemu help</filename>.
</note>
<literallayout class='monospaced'>
IMAGE_CLASSES += "qemuboot"
</literallayout>
</para>
</section>
<section id='migration-2.2-default-linker-hash-style-changed'>
<title>Default Linker Hash Style Changed</title>
<para>
The default linker hash style for <filename>gcc-cross</filename>
is now "sysv" in order to catch recipes that are building software
without using the OpenEmbedded
<link linkend='var-LDFLAGS'><filename>LDFLAGS</filename></link>.
This change could result in seeing some "No GNU_HASH in the elf
binary" QA issues when building such recipes.
You need to fix these recipes so that they use the expected
<filename>LDFLAGS</filename>.
Depending on how the software is built, the build system used by
the software (e.g. a Makefile) might need to be patched.
However, sometimes making this fix is as simple as adding the
following to the recipe:
<literallayout class='monospaced'>
TARGET_CC_ARCH += "${LDFLAGS}"
</literallayout>
</para>
</section>
<section id='migration-2.2-kernel-image-base-name-no-longer-uses-kernel-imagetype'>
<title><filename>KERNEL_IMAGE_BASE_NAME</filename> no Longer Uses <filename>KERNEL_IMAGETYPE</filename></title>
<para>
The
<filename>KERNEL_IMAGE_BASE_NAME</filename>
variable no longer uses the
<link linkend='var-KERNEL_IMAGETYPE'><filename>KERNEL_IMAGETYPE</filename></link>
variable to create the image's base name.
Because the OpenEmbedded build system can now build multiple kernel
image types, this part of the kernel image base name as been
removed leaving only the following:
<literallayout class='monospaced'>
KERNEL_IMAGE_BASE_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}-${DATETIME}"
</literallayout>
If you have recipes or classes that use
<filename>KERNEL_IMAGE_BASE_NAME</filename> directly, you might
need to update the references to ensure they continue to work.
</para>
</section>
<section id='migration-2.2-bitbake-changes'>
<title>BitBake Changes</title>
<para>
The following changes took place for BitBake:
<itemizedlist>
<listitem><para>
The "goggle" UI and standalone image-writer tool have
been removed as they both require GTK+ 2.0 and
were not being maintained.
</para></listitem>
<listitem><para>
The Perforce fetcher now supports
<link linkend='var-SRCREV'><filename>SRCREV</filename></link>
for specifying the source revision to use, be it
<filename>${</filename><link linkend='var-AUTOREV'><filename>AUTOREV</filename></link><filename>}</filename>,
changelist number, p4date, or label, in preference to
separate
<link linkend='var-SRC_URI'><filename>SRC_URI</filename></link>
parameters to specify these.
This change is more in-line with how the other fetchers
work for source control systems.
Recipes that fetch from Perforce will need to be updated
to use <filename>SRCREV</filename> in place of specifying
the source revision within
<filename>SRC_URI</filename>.
</para></listitem>
<listitem><para>
Some of BitBake's internal code structures for accessing
the recipe cache needed to be changed to support the new
multi-configuration functionality.
These changes will affect external tools that use BitBake's
tinfoil module.
For information on these changes, see the changes made to
the scripts supplied with OpenEmbedded-Core:
<ulink url='http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=189371f8393971d00bca0fceffd67cc07784f6ee'>1</ulink>
and
<ulink url='http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=4a5aa7ea4d07c2c90a1654b174873abb018acc67'>2</ulink>.
</para></listitem>
<listitem><para>
The task management code has been rewritten to avoid using
ID indirection in order to improve performance.
This change is unlikely to cause any problems for most
users.
However, the setscene verification function as pointed to
by <filename>BB_SETSCENE_VERIFY_FUNCTION</filename>
needed to change signature.
Consequently, a new variable named
<filename>BB_SETSCENE_VERIFY_FUNCTION2</filename>
has been added allowing multiple versions of BitBake
to work with suitably written metadata, which includes
OpenEmbedded-Core and Poky.
Anyone with custom BitBake task scheduler code might also
need to update the code to handle the new structure.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.2-swabber-has-been-removed'>
<title>Swabber has Been Removed</title>
<para>
Swabber, a tool that was intended to detect host contamination in
the build process, has been removed, as it has been unmaintained
and unused for some time and was never particularly effective.
The OpenEmbedded build system has since incorporated a number of
mechanisms including enhanced QA checks that mean that there is
less of a need for such a tool.
</para>
</section>
<section id='migration-2.2-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para>
<filename>augeas</filename>:
No longer needed and has been moved to
<filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>directfb</filename>:
Unmaintained and has been moved to
<filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>gcc</filename>:
Removed 4.9 version.
Versions 5.4 and 6.2 are still present.
</para></listitem>
<listitem><para>
<filename>gnome-doc-utils</filename>:
No longer needed.
</para></listitem>
<listitem><para>
<filename>gtk-doc-stub</filename>:
Replaced by <filename>gtk-doc</filename>.
</para></listitem>
<listitem><para>
<filename>gtk-engines</filename>:
No longer needed and has been moved to
<filename>meta-gnome</filename>.
</para></listitem>
<listitem><para>
<filename>gtk-sato-engine</filename>:
Became obsolete.
</para></listitem>
<listitem><para>
<filename>libglade</filename>:
No longer needed and has been moved to
<filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>libmad</filename>:
Unmaintained and functionally replaced by
<filename>libmpg123</filename>.
<filename>libmad</filename> has been moved to
<filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>libowl</filename>:
Became obsolete.
</para></listitem>
<listitem><para>
<filename>libxsettings-client</filename>:
No longer needed.
</para></listitem>
<listitem><para>
<filename>oh-puzzles</filename>:
Functionally replaced by
<filename>puzzles</filename>.
</para></listitem>
<listitem><para>
<filename>oprofileui</filename>:
Became obsolete.
OProfile has been largely supplanted by perf.
</para></listitem>
<listitem><para>
<filename>packagegroup-core-directfb.bb</filename>:
Removed.
</para></listitem>
<listitem><para>
<filename>core-image-directfb.bb</filename>:
Removed.
</para></listitem>
<listitem><para>
<filename>pointercal</filename>:
No longer needed and has been moved to
<filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>python-imaging</filename>:
No longer needed and moved to
<filename>meta-python</filename>
</para></listitem>
<listitem><para>
<filename>python-pyrex</filename>:
No longer needed and moved to
<filename>meta-python</filename>.
</para></listitem>
<listitem><para>
<filename>sato-icon-theme</filename>:
Became obsolete.
</para></listitem>
<listitem><para>
<filename>swabber-native</filename>:
Swabber has been removed.
See the
<link linkend='migration-2.2-swabber-has-been-removed'>entry on Swabber</link>.
</para></listitem>
<listitem><para>
<filename>tslib</filename>:
No longer needed and has been moved to
<filename>meta-oe</filename>.
</para></listitem>
<listitem><para>
<filename>uclibc</filename>:
Removed in favor of musl.
</para></listitem>
<listitem><para>
<filename>xtscal</filename>:
No longer needed and moved to
<filename>meta-oe</filename>
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.2-removed-classes'>
<title>Removed Classes</title>
<para>
The following classes have been removed:
<itemizedlist>
<listitem><para>
<filename>distutils-native-base</filename>:
No longer needed.
</para></listitem>
<listitem><para>
<filename>distutils3-native-base</filename>:
No longer needed.
</para></listitem>
<listitem><para>
<filename>sdl</filename>:
Only set
<link linkend='var-DEPENDS'><filename>DEPENDS</filename></link>
and
<link linkend='var-SECTION'><filename>SECTION</filename></link>,
which are better set within the recipe instead.
</para></listitem>
<listitem><para>
<filename>sip</filename>:
Mostly unused.
</para></listitem>
<listitem><para>
<filename>swabber</filename>:
See the
<link linkend='migration-2.2-swabber-has-been-removed'>entry on Swabber</link>.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.2-minor-packaging-changes'>
<title>Minor Packaging Changes</title>
<para>
The following minor packaging changes have occurred:
<itemizedlist>
<listitem><para>
<filename>grub</filename>:
Split <filename>grub-editenv</filename> into its own
package.
</para></listitem>
<listitem><para>
<filename>systemd</filename>:
Split container and vm related units into a new package,
systemd-container.
</para></listitem>
<listitem><para>
<filename>util-linux</filename>:
Moved <filename>prlimit</filename> to a separate
<filename>util-linux-prlimit</filename> package.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.2-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following miscellaneous changes have occurred:
<itemizedlist>
<listitem><para>
<filename>package_regex.inc</filename>:
Removed because the definitions
<filename>package_regex.inc</filename> previously contained
have been moved to their respective recipes.
</para></listitem>
<listitem><para>
Both <filename>devtool add</filename> and
<filename>recipetool create</filename> now use a fixed
<link linkend='var-SRCREV'><filename>SRCREV</filename></link>
by default when fetching from a Git repository.
You can override this in either case to use
<filename>${</filename><link linkend='var-AUTOREV'><filename>AUTOREV</filename></link><filename>}</filename>
instead by using the <filename>-a</filename> or
<filename>&dash;&dash;autorev</filename> command-line
option
</para></listitem>
<listitem><para>
<filename>distcc</filename>:
GTK+ UI is now disabled by default.
</para></listitem>
<listitem><para>
<filename>packagegroup-core-tools-testapps</filename>:
Removed Piglit.
</para></listitem>
<listitem><para>
<filename>image.bbclass</filename>:
Renamed COMPRESS(ION) to CONVERSION.
This change means that
<filename>COMPRESSIONTYPES</filename>,
<filename>COMPRESS_DEPENDS</filename> and
<filename>COMPRESS_CMD</filename> are deprecated in favor
of <filename>CONVERSIONTYPES</filename>,
<filename>CONVERSION_DEPENDS</filename> and
<filename>CONVERSION_CMD</filename>.
The <filename>COMPRESS*</filename> variable names will
still work in the 2.2 release but metadata that does not
need to be backwards-compatible should be changed to
use the new names as the <filename>COMPRESS*</filename>
ones will be removed in a future release.
</para></listitem>
<listitem><para>
<filename>gtk-doc</filename>:
A full version of <filename>gtk-doc</filename> is now
made available.
However, some old software might not be capable of using
the current version of <filename>gtk-doc</filename>
to build documentation.
You need to change recipes that build such software so that
they explicitly disable building documentation with
<filename>gtk-doc</filename>.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.3-release'>
<title>Moving to the Yocto Project 2.3 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.3 Release from the prior release.
</para>
<section id='migration-2.3-recipe-specific-sysroots'>
<title>Recipe-specific Sysroots</title>
<para>
The OpenEmbedded build system now uses one sysroot per
recipe to resolve long-standing issues with configuration
script auto-detection of undeclared dependencies.
Consequently, you might find that some of your previously
written custom recipes are missing declared dependencies,
particularly those dependencies that are incidentally built
earlier in a typical build process and thus are already likely
to be present in the shared sysroot in previous releases.
</para>
<para>
Consider the following:
<itemizedlist>
<listitem><para>
<emphasis>Declare Build-Time Dependencies:</emphasis>
Because of this new feature, you must explicitly
declare all build-time dependencies for your recipe.
If you do not declare these dependencies, they are not
populated into the sysroot for the recipe.
</para></listitem>
<listitem><para>
<emphasis>Specify Pre-Installation and Post-Installation
Native Tool Dependencies:</emphasis>
You must specifically specify any special native tool
dependencies of <filename>pkg_preinst</filename> and
<filename>pkg_postinst</filename> scripts by using the
<link linkend='var-PACKAGE_WRITE_DEPS'><filename>PACKAGE_WRITE_DEPS</filename></link>
variable.
Specifying these dependencies ensures that these tools
are available if these scripts need to be run on the
build host during the
<link linkend='ref-tasks-rootfs'><filename>do_rootfs</filename></link>
task.</para>
<para>As an example, see the <filename>dbus</filename>
recipe.
You will see that this recipe has a
<filename>pkg_postinst</filename> that calls
<filename>systemctl</filename> if "systemd" is in
<link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link>.
In the example,
<filename>systemd-systemctl-native</filename> is added to
<filename>PACKAGE_WRITE_DEPS</filename>, which is also
conditional on "systemd" being in
<filename>DISTRO_FEATURES</filename>.
</para></listitem>
<listitem><para>
<emphasis>Examine Recipes that Use
<filename>SSTATEPOSTINSTFUNCS</filename>:</emphasis>
You need to examine any recipe that uses
<filename>SSTATEPOSTINSTFUNCS</filename> and determine
steps to take.</para>
<para>Functions added to
<filename>SSTATEPOSTINSTFUNCS</filename> are still
called as they were in previous Yocto Project releases.
However, since a separate sysroot is now being populated
for every recipe and if existing functions being called
through <filename>SSTATEPOSTINSTFUNCS</filename> are
doing relocation, then you will need to change these
to use a post-installation script that is installed by a
function added to
<link linkend='var-SYSROOT_PREPROCESS_FUNCS'><filename>SYSROOT_PREPROCESS_FUNCS</filename></link>.
</para>
<para>For an example, see the
<filename>pixbufcache</filename> class in
<filename>meta/classes/</filename> in the Yocto Project
<ulink url='&YOCTO_DOCS_OM_URL;#source-repositories'>Source Repositories</ulink>.
<note>
The <filename>SSTATEPOSTINSTFUNCS</filename> variable
itself is now deprecated in favor of the
<filename>do_populate_sysroot[postfuncs]</filename>
task.
Consequently, if you do still have any function or
functions that need to be called after the sysroot
component is created for a recipe, then you would be
well advised to take steps to use a post installation
script as described previously.
Taking these steps prepares your code for when
<filename>SSTATEPOSTINSTFUNCS</filename> is
removed in a future Yocto Project release.
</note>
</para></listitem>
<listitem><para>
<emphasis>Specify the Sysroot when Using Certain
External Scripts:</emphasis>
Because the shared sysroot is now gone, the scripts
<filename>oe-find-native-sysroot</filename> and
<filename>oe-run-native</filename> have been changed such
that you need to specify which recipe's
<link linkend='var-STAGING_DIR_NATIVE'><filename>STAGING_DIR_NATIVE</filename></link>
is used.
</para></listitem>
</itemizedlist>
<note>
You can find more information on how recipe-specific sysroots
work in the
"<link linkend='ref-classes-staging'><filename>staging.bbclass</filename></link>"
section.
</note>
</para>
</section>
<section id='migration-2.3-path-variable'>
<title><filename>PATH</filename> Variable</title>
<para>
Within the environment used to run build tasks, the environment
variable <filename>PATH</filename> is now sanitized such that
the normal native binary paths
(<filename>/bin</filename>, <filename>/sbin</filename>,
<filename>/usr/bin</filename> and so forth) are
removed and a directory containing symbolic links linking only
to the binaries from the host mentioned in the
<link linkend='var-HOSTTOOLS'><filename>HOSTTOOLS</filename></link>
and
<link linkend='var-HOSTTOOLS_NONFATAL'><filename>HOSTTOOLS_NONFATAL</filename></link>
variables is added to <filename>PATH</filename>.
</para>
<para>
Consequently, any native binaries provided by the host that you
need to call needs to be in one of these two variables at
the configuration level.
</para>
<para>
Alternatively, you can add a native recipe (i.e.
<filename>-native</filename>) that provides the
binary to the recipe's
<link linkend='var-DEPENDS'><filename>DEPENDS</filename></link>
value.
<note>
<filename>PATH</filename> is not sanitized in the same way
within <filename>devshell</filename>.
If it were, you would have difficulty running host tools for
development and debugging within the shell.
</note>
</para>
</section>
<section id='migration-2.3-scripts'>
<title>Changes to Scripts</title>
<para>
The following changes to scripts took place:
<itemizedlist>
<listitem><para>
<emphasis><filename>oe-find-native-sysroot</filename>:</emphasis>
The usage for the
<filename>oe-find-native-sysroot</filename> script has
changed to the following:
<literallayout class='monospaced'>
$ . oe-find-native-sysroot <replaceable>recipe</replaceable>
</literallayout>
You must now supply a recipe for
<replaceable>recipe</replaceable> as part of the command.
Prior to the Yocto Project &DISTRO; release, it was not
necessary to provide the script with the command.
</para></listitem>
<listitem><para>
<emphasis><filename>oe-run-native</filename>:</emphasis>
The usage for the
<filename>oe-run-native</filename> script has changed
to the following:
<literallayout class='monospaced'>
$ oe-run-native <replaceable>native_recipe</replaceable> <replaceable>tool</replaceable>
</literallayout>
You must supply the name of the native recipe and the tool
you want to run as part of the command.
Prior to the Yocto Project &DISTRO; release, it was not
necessary to provide the native recipe with the command.
</para></listitem>
<listitem><para>
<emphasis><filename>cleanup-workdir</filename>:</emphasis>
The <filename>cleanup-workdir</filename> script has been
removed because the script was found to be deleting
files it should not have, which lead to broken build
trees.
Rather than trying to delete portions of
<link linkend='var-TMPDIR'><filename>TMPDIR</filename></link>
and getting it wrong, it is recommended that you
delete <filename>TMPDIR</filename> and have it restored
from shared state (sstate) on subsequent builds.
</para></listitem>
<listitem><para>
<emphasis><filename>wipe-sysroot</filename>:</emphasis>
The <filename>wipe-sysroot</filename> script has been
removed as it is no longer needed with recipe-specific
sysroots.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.3-functions'>
<title>Changes to Functions</title>
<para>
The previously deprecated
<filename>bb.data.getVar()</filename>,
<filename>bb.data.setVar()</filename>, and
related functions have been removed in favor of
<filename>d.getVar()</filename>,
<filename>d.setVar()</filename>, and so forth.
</para>
<para>
You need to fix any references to these old functions.
</para>
</section>
<section id='migration-2.3-bitbake-changes'>
<title>BitBake Changes</title>
<para>
The following changes took place for BitBake:
<itemizedlist>
<listitem><para>
<emphasis>BitBake's Graphical Dependency Explorer UI Replaced:</emphasis>
BitBake's graphical dependency explorer UI
<filename>depexp</filename> was replaced by
<filename>taskexp</filename> ("Task Explorer"), which
provides a graphical way of exploring the
<filename>task-depends.dot</filename> file.
The data presented by Task Explorer is much more
accurate than the data that was presented by
<filename>depexp</filename>.
Being able to visualize the data is an often requested
feature as standard <filename>*.dot</filename> file
viewers cannot usual cope with the size of
the <filename>task-depends.dot</filename> file.
</para></listitem>
<listitem><para>
<emphasis>BitBake "-g" Output Changes:</emphasis>
The <filename>package-depends.dot</filename> and
<filename>pn-depends.dot</filename> files as previously
generated using the <filename>bitbake -g</filename> command
have been removed.
A <filename>recipe-depends.dot</filename> file
is now generated as a collapsed version of
<filename>task-depends.dot</filename> instead.
</para>
<para>The reason for this change is because
<filename>package-depends.dot</filename> and
<filename>pn-depends.dot</filename> largely date back
to a time before task-based execution and do not take
into account task-level dependencies between recipes,
which could be misleading.
</para></listitem>
<listitem><para>
<emphasis>Mirror Variable Splitting Changes:</emphasis>
Mirror variables including
<link linkend='var-MIRRORS'><filename>MIRRORS</filename></link>,
<link linkend='var-PREMIRRORS'><filename>PREMIRRORS</filename></link>,
and
<link linkend='var-SSTATE_MIRRORS'><filename>SSTATE_MIRRORS</filename></link>
can now separate values entirely with spaces.
Consequently, you no longer need "\\n".
BitBake looks for pairs of values, which simplifies usage.
There should be no change required to existing mirror
variable values themselves.
</para></listitem>
<listitem><para>
<emphasis>The Subversion (SVN) Fetcher Uses an "ssh" Parameter and Not an "rsh" Parameter:</emphasis>
The SVN fetcher now takes an "ssh" parameter instead of an
"rsh" parameter.
This new optional parameter is used when the "protocol"
parameter is set to "svn+ssh".
You can only use the new parameter to specify the
<filename>ssh</filename> program used by SVN.
The SVN fetcher passes the new parameter through the
<filename>SVN_SSH</filename> environment variable during
the
<link linkend='ref-tasks-fetch'><filename>do_fetch</filename></link>
task.</para>
<para>See the
"<ulink url='&YOCTO_DOCS_BB_URL;#svn-fetcher'>Subversion (SVN) Fetcher (svn://)</ulink>"
section in the BitBake User Manual for additional
information.
</para></listitem>
<listitem><para>
<emphasis><filename>BB_SETSCENE_VERIFY_FUNCTION</filename>
and <filename>BB_SETSCENE_VERIFY_FUNCTION2</filename>
Removed:</emphasis>
Because the mechanism they were part of is no longer
necessary with recipe-specific sysroots, the
<filename>BB_SETSCENE_VERIFY_FUNCTION</filename> and
<filename>BB_SETSCENE_VERIFY_FUNCTION2</filename>
variables have been removed.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.3-absolute-symlinks'>
<title>Absolute Symbolic Links</title>
<para>
Absolute symbolic links (symlinks) within staged files are no
longer permitted and now trigger an error.
Any explicit creation of symlinks can use the
<filename>lnr</filename> script, which is a replacement for
<filename>ln -r</filename>.
</para>
<para>
If the build scripts in the software that the recipe is building
are creating a number of absolute symlinks that need to be
corrected, you can inherit
<filename>relative_symlinks</filename> within the recipe to turn
those absolute symlinks into relative symlinks.
</para>
</section>
<section id='migration-2.3-gplv2-and-gplv3-moves'>
<title>GPLv2 Versions of GPLv3 Recipes Moved</title>
<para>
Older GPLv2 versions of GPLv3 recipes have moved to a
separate <filename>meta-gplv2</filename> layer.
</para>
<para>
If you use
<link linkend='var-INCOMPATIBLE_LICENSE'><filename>INCOMPATIBLE_LICENSE</filename></link>
to exclude GPLv3 or set
<link linkend='var-PREFERRED_VERSION'><filename>PREFERRED_VERSION</filename></link>
to substitute a GPLv2 version of a GPLv3 recipe, then you must add
the <filename>meta-gplv2</filename> layer to your configuration.
<note>
You can find <filename>meta-gplv2</filename> layer in the
OpenEmbedded layer index at
<ulink url='https://layers.openembedded.org/layerindex/branch/master/layer/meta-gplv2/'></ulink>.
</note>
</para>
<para>
These relocated GPLv2 recipes do not receive the same level of
maintenance as other core recipes.
The recipes do not get security fixes and upstream no longer
maintains them.
In fact, the upstream community is actively hostile towards people
that use the old versions of the recipes.
Moving these recipes into a separate layer both makes the different
needs of the recipes clearer and clearly identifies the number of
these recipes.
<note>
The long-term solution might be to move to BSD-licensed
replacements of the GPLv3 components for those that need to
exclude GPLv3-licensed components from the target system.
This solution will be investigated for future Yocto
Project releases.
</note>
</para>
</section>
<section id='migration-2.3-package-management-changes'>
<title>Package Management Changes</title>
<para>
The following package management changes took place:
<itemizedlist>
<listitem><para>
Smart package manager is replaced by DNF package manager.
Smart has become unmaintained upstream, is not ported
to Python 3.x.
Consequently, Smart needed to be replaced.
DNF is the only feasible candidate.</para>
<para>The change in functionality is that the on-target
runtime package management from remote package feeds is
now done with a different tool that has a
different set of command-line options.
If you have scripts that call the
tool directly, or use its API, they need to be fixed.</para>
<para>For more information, see the
<ulink url='http://dnf.readthedocs.io/en/latest/'>DNF Documentation</ulink>.
</para></listitem>
<listitem><para>
Rpm 5.x is replaced with Rpm 4.x.
This is done for two major reasons:
<itemizedlist>
<listitem><para>
DNF is API-incompatible with Rpm 5.x and porting
it and maintaining the port is non-trivial.
</para></listitem>
<listitem><para>
Rpm 5.x itself has limited maintenance upstream,
and the Yocto Project is one of the very few
remaining users.
</para></listitem>
</itemizedlist>
</para></listitem>
<listitem><para>
Berkeley DB 6.x is removed and Berkeley DB 5.x becomes
the default:
<itemizedlist>
<listitem><para>
Version 6.x of Berkeley DB has largely been
rejected by the open source community due to its
AGPLv3 license.
As a result, most mainstream open source projects
that require DB are still developed and tested with
DB 5.x.
</para></listitem>
<listitem><para>
In OE-core, the only thing that was requiring
DB 6.x was Rpm 5.x.
Thus, no reason exists to continue carrying DB 6.x
in OE-core.
</para></listitem>
</itemizedlist>
</para></listitem>
<listitem><para>
<filename>createrepo</filename> is replaced with
<filename>createrepo_c</filename>.</para>
<para><filename>createrepo_c</filename> is the current
incarnation of the tool that generates remote repository
metadata.
It is written in C as compared to
<filename>createrepo</filename>, which is written in
Python.
<filename>createrepo_c</filename> is faster and is
maintained.
</para></listitem>
<listitem><para>
Architecture-independent RPM packages are "noarch"
instead of "all".</para>
<para>This change was made because too many places in
DNF/RPM4 stack already make that assumption.
Only the filenames and the architecture tag has changed.
Nothing else has changed in OE-core system, particularly
in the
<link linkend='ref-classes-allarch'><filename>allarch.bbclass</filename></link>
class.
</para></listitem>
<listitem><para>
Signing of remote package feeds using
<filename>PACKAGE_FEED_SIGN</filename>
is not currently supported.
This issue will be fully addressed in a future
Yocto Project release.
See <ulink url='https://bugzilla.yoctoproject.org/show_bug.cgi?id=11209'>defect 11209</ulink>
for more information on a solution to package feed
signing with RPM in the Yocto Project 2.3 release.
</para></listitem>
<listitem><para>
OPKG now uses the libsolv backend for resolving package
dependencies by default.
This is vastly superior to OPKG's internal ad-hoc solver
that was previously used.
This change does have a small impact on disk (around
500 KB) and memory footprint.
<note>
For further details on this change, see the
<ulink url='http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?
id=f4d4f99cfbc2396e49c1613a7d237b9e57f06f81'>commit message</ulink>.
</note>
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.3-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para>
<emphasis><filename>linux-yocto 4.8:</filename></emphasis>
Version 4.8 has been removed.
Versions 4.1 (LTSI), 4.4 (LTS), 4.9 (LTS/LTSI) and 4.10
are now present.
</para></listitem>
<listitem><para>
<emphasis><filename>python-smartpm:</filename></emphasis>
Functionally replaced by <filename>dnf</filename>.
</para></listitem>
<listitem><para>
<emphasis><filename>createrepo:</filename></emphasis>
Replaced by the <filename>createrepo-c</filename> recipe.
</para></listitem>
<listitem><para>
<emphasis><filename>rpmresolve:</filename></emphasis>
No longer needed with the move to RPM 4 as RPM itself is
used instead.
</para></listitem>
<listitem><para>
<emphasis><filename>gstreamer:</filename></emphasis>
Removed the GStreamer Git version recipes as they have
been stale.
<filename>1.10.</filename><replaceable>x</replaceable>
recipes are still present.
</para></listitem>
<listitem><para>
<emphasis><filename>alsa-conf-base:</filename></emphasis>
Merged into <filename>alsa-conf</filename> since
<filename>libasound</filename> depended on both.
Essentially, no way existed to install only one of these.
</para></listitem>
<listitem><para>
<emphasis><filename>tremor:</filename></emphasis>
Moved to <filename>meta-multimedia</filename>.
Fixed-integer Vorbis decoding is not
needed by current hardware.
Thus, GStreamer's ivorbis plugin has been disabled
by default eliminating the need for the
<filename>tremor</filename> recipe in
<link linkend='oe-core'>OE-Core</link>.
</para></listitem>
<listitem><para>
<emphasis><filename>gummiboot:</filename></emphasis>
Replaced by <filename>systemd-boot</filename>.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.3-wic-changes'>
<title>Wic Changes</title>
<para>
The following changes have been made to Wic:
<note>
For more information on Wic, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#creating-partitioned-images-using-wic'>Creating Partitioned Images Using Wic</ulink>"
section in the Yocto Project Development Tasks Manual.
</note>
<itemizedlist>
<listitem><para>
<emphasis>Default Output Directory Changed:</emphasis>
Wic's default output directory is now the current directory
by default instead of the unusual
<filename>/var/tmp/wic</filename>.</para>
<para>The "-o" and "--outdir" options remain unchanged
and are used to specify your preferred output directory
if you do not want to use the default directory.
</para></listitem>
<listitem><para>
<emphasis>fsimage Plug-in Removed:</emphasis>
The Wic fsimage plugin has been removed as it duplicates
functionality of the rawcopy plugin.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.3-qa-changes'>
<title>QA Changes</title>
<para>
The following QA checks have changed:
<itemizedlist>
<listitem><para>
<emphasis><filename>unsafe-references-in-binaries</filename>:</emphasis>
The <filename>unsafe-references-in-binaries</filename>
QA check, which was disabled by default, has now been
removed.
This check was intended to detect binaries in
<filename>/bin</filename> that link to libraries in
<filename>/usr/lib</filename> and have the case where
the user has <filename>/usr</filename> on a separate
filesystem to <filename>/</filename>.</para>
<para>The removed QA check was buggy.
Additionally, <filename>/usr</filename> residing on a
separate partition from <filename>/</filename> is now
a rare configuration.
Consequently,
<filename>unsafe-references-in-binaries</filename> was
removed.
</para></listitem>
<listitem><para>
<emphasis><filename>file-rdeps</filename>:</emphasis>
The <filename>file-rdeps</filename> QA check is now an
error by default instead of a warning.
Because it is an error instead of a warning, you need to
address missing runtime dependencies.</para>
<para>For additional information, see the
<link linkend='ref-classes-insane'><filename>insane</filename></link>
class and the
"<link linkend='qa-errors-and-warnings'>Errors and Warnings</link>"
section.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.3-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following miscellaneous changes have occurred:
<itemizedlist>
<listitem><para>
In this release, a number of recipes have been changed to
ignore the <filename>largefile</filename>
<link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link>
item, enabling large file support unconditionally.
This feature has always been enabled by default.
Disabling the feature has not been widely tested.
<note>
Future releases of the Yocto Project will remove
entirely the ability to disable the
<filename>largefile</filename> feature,
which would make it unconditionally enabled everywhere.
</note>
</para></listitem>
<listitem><para>
If the
<link linkend='var-DISTRO_VERSION'><filename>DISTRO_VERSION</filename></link>
value contains the value of the
<link linkend='var-DATE'><filename>DATE</filename></link>
variable, which is the default between Poky releases,
the <filename>DATE</filename> value is explicitly excluded
from <filename>/etc/issue</filename> and
<filename>/etc/issue.net</filename>, which is displayed at
the login prompt, in order to avoid conflicts with
Multilib enabled.
Regardless, the <filename>DATE</filename> value is
inaccurate if the <filename>base-files</filename>
recipe is restored from shared state (sstate) rather
than rebuilt.</para>
<para>If you need the build date recorded in
<filename>/etc/issue*</filename> or anywhere else in your
image, a better method is to define a post-processing
function to do it and have the function called from
<link linkend='var-ROOTFS_POSTPROCESS_COMMAND'><filename>ROOTFS_POSTPROCESS_COMMAND</filename></link>.
Doing so ensures the value is always up-to-date with the
created image.
</para></listitem>
<listitem><para>
Dropbear's <filename>init</filename> script now disables
DSA host keys by default.
This change is in line with the systemd service
file, which supports RSA keys only, and with recent
versions of OpenSSH, which deprecates DSA host keys.
</para></listitem>
<listitem><para>
The
<link linkend='ref-classes-buildhistory'><filename>buildhistory</filename></link>
class now correctly uses tabs as separators between all
columns in <filename>installed-package-sizes.txt</filename>
in order to aid import into other tools.
</para></listitem>
<listitem><para>
The <filename>USE_LDCONFIG</filename> variable has been
replaced with the "ldconfig"
<filename>DISTRO_FEATURES</filename> feature.
Distributions that previously set:
<literallayout class='monospaced'>
USE_LDCONFIG = "0"
</literallayout>
should now instead use the following:
<literallayout class='monospaced'>
DISTRO_FEATURES_BACKFILL_CONSIDERED_append = " ldconfig"
</literallayout>
</para></listitem>
<listitem><para>
The default value of
<link linkend='var-COPYLEFT_LICENSE_INCLUDE'><filename>COPYLEFT_LICENSE_INCLUDE</filename></link>
now includes all versions of AGPL licenses in addition
to GPL and LGPL.
<note>
The default list is not intended to be guaranteed
as a complete safe list.
You should seek legal advice based on what you are
distributing if you are unsure.
</note>
</para></listitem>
<listitem><para>
Kernel module packages are now suffixed with the kernel
version in order to allow module packages from multiple
kernel versions to co-exist on a target system.
If you wish to return to the previous naming scheme
that does not include the version suffix, use the
following:
<literallayout class='monospaced'>
KERNEL_MODULE_PACKAGE_SUFFIX to ""
</literallayout>
</para></listitem>
<listitem><para>
Removal of <filename>libtool</filename>
<filename>*.la</filename> files is now enabled by default.
The <filename>*.la</filename> files are not actually
needed on Linux and relocating them is an unnecessary
burden.</para>
<para>If you need to preserve these
<filename>.la</filename> files (e.g. in a custom
distribution), you must change
<link linkend='var-INHERIT_DISTRO'><filename>INHERIT_DISTRO</filename></link>
such that "remove-libtool" is not included in the value.
</para></listitem>
<listitem><para>
Extensible SDKs built for GCC 5+ now refuse to install on a
distribution where the host GCC version is 4.8 or 4.9.
This change resulted from the fact that the installation
is known to fail due to the way the
<filename>uninative</filename> shared state (sstate)
package is built.
See the
<link linkend='ref-classes-uninative'><filename>uninative</filename></link>
class for additional information.
</para></listitem>
<listitem><para>
All native and nativesdk recipes now use a separate
<filename>DISTRO_FEATURES</filename> value instead of
sharing the value used by recipes for the target, in order
to avoid unnecessary rebuilds.</para>
<para>The <filename>DISTRO_FEATURES</filename> for
<filename>native</filename> recipes is
<link linkend='var-DISTRO_FEATURES_NATIVE'><filename>DISTRO_FEATURES_NATIVE</filename></link>
added to an intersection of
<filename>DISTRO_FEATURES</filename> and
<link linkend='var-DISTRO_FEATURES_FILTER_NATIVE'><filename>DISTRO_FEATURES_FILTER_NATIVE</filename></link>.
</para>
<para>For nativesdk recipes, the
corresponding variables are
<link linkend='var-DISTRO_FEATURES_NATIVESDK'><filename>DISTRO_FEATURES_NATIVESDK</filename></link>
and
<link linkend='var-DISTRO_FEATURES_FILTER_NATIVESDK'><filename>DISTRO_FEATURES_FILTER_NATIVESDK</filename></link>.
</para></listitem>
<listitem><para>
The <filename>FILESDIR</filename>
variable, which was previously deprecated and rarely used,
has now been removed.
You should change any recipes that set
<filename>FILESDIR</filename> to set
<link linkend='var-FILESPATH'><filename>FILESPATH</filename></link>
instead.
</para></listitem>
<listitem><para>
The <filename>MULTIMACH_HOST_SYS</filename>
variable has been removed as it is no longer needed
with recipe-specific sysroots.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.4-release'>
<title>Moving to the Yocto Project 2.4 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.4 Release from the prior release.
</para>
<section id='migration-2.4-memory-resident-mode'>
<title>Memory Resident Mode</title>
<para>
A persistent mode is now available in BitBake's default operation,
replacing its previous "memory resident mode" (i.e.
<filename>oe-init-build-env-memres</filename>).
Now you only need to set
<link linkend='var-BB_SERVER_TIMEOUT'><filename>BB_SERVER_TIMEOUT</filename></link>
to a timeout (in seconds) and BitBake's server stays resident for
that amount of time between invocations.
The <filename>oe-init-build-env-memres</filename> script has been
removed since a separate environment setup script is no longer
needed.
</para>
</section>
<section id='migration-2.4-packaging-changes'>
<title>Packaging Changes</title>
<para>
This section provides information about packaging changes that have
occurred:
<itemizedlist>
<listitem><para>
<emphasis><filename>python3</filename> Changes:</emphasis>
<itemizedlist>
<listitem><para>
The main "python3" package now brings in all of the
standard Python 3 distribution rather than a subset.
This behavior matches what is expected based on
traditional Linux distributions.
If you wish to install a subset of Python 3, specify
<filename>python-core</filename> plus one or more of
the individual packages that are still produced.
</para></listitem>
<listitem><para>
<emphasis><filename>python3</filename>:</emphasis>
The <filename>bz2.py</filename>,
<filename>lzma.py</filename>, and
<filename>_compression.py</filename> scripts have
been moved from the
<filename>python3-misc</filename> package to
the <filename>python3-compression</filename> package.
</para></listitem>
</itemizedlist>
</para></listitem>
<listitem><para>
<emphasis><filename>binutils</filename>:</emphasis>
The <filename>libbfd</filename> library is now packaged in
a separate "libbfd" package.
This packaging saves space when certain tools
(e.g. <filename>perf</filename>) are installed.
In such cases, the tools only need
<filename>libbfd</filename> rather than all the packages in
<filename>binutils</filename>.
</para></listitem>
<listitem><para>
<emphasis><filename>util-linux</filename> Changes:</emphasis>
<itemizedlist>
<listitem><para>
The <filename>su</filename> program is now packaged
in a separate "util-linux-su" package, which is only
built when "pam" is listed in the
<link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link>
variable.
<filename>util-linux</filename> should not be
installed unless it is needed because
<filename>su</filename> is normally provided through
the shadow file format.
The main <filename>util-linux</filename> package has
runtime dependencies (i.e.
<link linkend='var-RDEPENDS'><filename>RDEPENDS</filename></link>)
on the <filename>util-linux-su</filename> package
when "pam" is in
<filename>DISTRO_FEATURES</filename>.
</para></listitem>
<listitem><para>
The <filename>switch_root</filename> program is now
packaged in a separate "util-linux-switch-root"
package for small initramfs images that do not need
the whole <filename>util-linux</filename> package or
the busybox binary, which are both much larger than
<filename>switch_root</filename>.
The main <filename>util-linux</filename> package has
a recommended runtime dependency (i.e.
<link linkend='var-RRECOMMENDS'><filename>RRECOMMENDS</filename></link>)
on the <filename>util-linux-switch-root</filename> package.
</para></listitem>
<listitem><para>
The <filename>ionice</filename> program is now
packaged in a separate "util-linux-ionice" package.
The main <filename>util-linux</filename> package has
a recommended runtime dependency (i.e.
<filename>RRECOMMENDS</filename>)
on the <filename>util-linux-ionice</filename> package.
</para></listitem>
</itemizedlist>
</para></listitem>
<listitem><para>
<emphasis><filename>initscripts</filename>:</emphasis>
The <filename>sushell</filename> program is now packaged in
a separate "initscripts-sushell" package.
This packaging change allows systems to pull
<filename>sushell</filename> in when
<filename>selinux</filename> is enabled.
The change also eliminates needing to pull in the entire
<filename>initscripts</filename> package.
The main <filename>initscripts</filename> package has a
runtime dependency (i.e. <filename>RDEPENDS</filename>)
on the <filename>sushell</filename> package when
"selinux" is in <filename>DISTRO_FEATURES</filename>.
</para></listitem>
<listitem><para>
<emphasis><filename>glib-2.0</filename>:</emphasis>
The <filename>glib-2.0</filename> package now has a
recommended runtime dependency (i.e.
<filename>RRECOMMENDS</filename>) on the
<filename>shared-mime-info</filename> package, since large
portions of GIO are not useful without the MIME database.
You can remove the dependency by using the
<link linkend='var-BAD_RECOMMENDATIONS'><filename>BAD_RECOMMENDATIONS</filename></link>
variable if <filename>shared-mime-info</filename> is too
large and is not required.
</para></listitem>
<listitem><para>
<emphasis>Go Standard Runtime:</emphasis>
The Go standard runtime has been split out from the main
<filename>go</filename> recipe into a separate
<filename>go-runtime</filename> recipe.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.4-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para>
<emphasis><filename>acpitests</filename>:</emphasis>
This recipe is not maintained.
</para></listitem>
<listitem><para>
<emphasis><filename>autogen-native</filename>:</emphasis>
No longer required by Grub, oe-core, or meta-oe.
</para></listitem>
<listitem><para>
<emphasis><filename>bdwgc</filename>:</emphasis>
Nothing in OpenEmbedded-Core requires this recipe.
It has moved to meta-oe.
</para></listitem>
<listitem><para>
<emphasis><filename>byacc</filename>:</emphasis>
This recipe was only needed by rpm 5.x and has moved to
meta-oe.
</para></listitem>
<listitem><para>
<emphasis><filename>gcc (5.4)</filename>:</emphasis>
The 5.4 series dropped the recipe in favor of 6.3 / 7.2.
</para></listitem>
<listitem><para>
<emphasis><filename>gnome-common</filename>:</emphasis>
Deprecated upstream and no longer needed.
</para></listitem>
<listitem><para>
<emphasis><filename>go-bootstrap-native</filename>:</emphasis>
Go 1.9 does its own bootstrapping so this recipe has been
removed.
</para></listitem>
<listitem><para>
<emphasis><filename>guile</filename>:</emphasis>
This recipe was only needed by
<filename>autogen-native</filename> and
<filename>remake</filename>.
The recipe is no longer needed by either of these programs.
</para></listitem>
<listitem><para>
<emphasis><filename>libclass-isa-perl</filename>:</emphasis>
This recipe was previously needed for LSB 4, no longer
needed.
</para></listitem>
<listitem><para>
<emphasis><filename>libdumpvalue-perl</filename>:</emphasis>
This recipe was previously needed for LSB 4, no longer
needed.
</para></listitem>
<listitem><para>
<emphasis><filename>libenv-perl</filename>:</emphasis>
This recipe was previously needed for LSB 4, no longer
needed.
</para></listitem>
<listitem><para>
<emphasis><filename>libfile-checktree-perl</filename>:</emphasis>
This recipe was previously needed for LSB 4, no longer
needed.
</para></listitem>
<listitem><para>
<emphasis><filename>libi18n-collate-perl</filename>:</emphasis>
This recipe was previously needed for LSB 4, no longer
needed.
</para></listitem>
<listitem><para>
<emphasis><filename>libiconv</filename>:</emphasis>
This recipe was only needed for <filename>uclibc</filename>,
which was removed in the previous release.
<filename>glibc</filename> and <filename>musl</filename>
have their own implementations.
<filename>meta-mingw</filename> still needs
<filename>libiconv</filename>, so it has
been moved to <filename>meta-mingw</filename>.
</para></listitem>
<listitem><para>
<emphasis><filename>libpng12</filename>:</emphasis>
This recipe was previously needed for LSB. The current
<filename>libpng</filename> is 1.6.x.
</para></listitem>
<listitem><para>
<emphasis><filename>libpod-plainer-perl</filename>:</emphasis>
This recipe was previously needed for LSB 4, no longer
needed.
</para></listitem>
<listitem><para>
<emphasis><filename>linux-yocto (4.1)</filename>:</emphasis>
This recipe was removed in favor of 4.4, 4.9, 4.10 and 4.12.
</para></listitem>
<listitem><para>
<emphasis><filename>mailx</filename>:</emphasis>
This recipe was previously only needed for LSB
compatibility, and upstream is defunct.
</para></listitem>
<listitem><para>
<emphasis><filename>mesa (git version only)</filename>:</emphasis>
The git version recipe was stale with respect to the release
version.
</para></listitem>
<listitem><para>
<emphasis><filename>ofono (git version only)</filename>:</emphasis>
The git version recipe was stale with respect to the release
version.
</para></listitem>
<listitem><para>
<emphasis><filename>portmap</filename>:</emphasis>
This recipe is obsolete and is superseded by
<filename>rpcbind</filename>.
</para></listitem>
<listitem><para>
<emphasis><filename>python3-pygpgme</filename>:</emphasis>
This recipe is old and unmaintained. It was previously
required by <filename>dnf</filename>, which has switched
to official <filename>gpgme</filename> Python bindings.
</para></listitem>
<listitem><para>
<emphasis><filename>python-async</filename>:</emphasis>
This recipe has been removed in favor of the Python 3
version.
</para></listitem>
<listitem><para>
<emphasis><filename>python-gitdb</filename>:</emphasis>
This recipe has been removed in favor of the Python 3
version.
</para></listitem>
<listitem><para>
<emphasis><filename>python-git</filename>:</emphasis>
This recipe was removed in favor of the Python 3
version.
</para></listitem>
<listitem><para>
<emphasis><filename>python-mako</filename>:</emphasis>
This recipe was removed in favor of the Python 3
version.
</para></listitem>
<listitem><para>
<emphasis><filename>python-pexpect</filename>:</emphasis>
This recipe was removed in favor of the Python 3 version.
</para></listitem>
<listitem><para>
<emphasis><filename>python-ptyprocess</filename>:</emphasis>
This recipe was removed in favor of Python the 3 version.
</para></listitem>
<listitem><para>
<emphasis><filename>python-pycurl</filename>:</emphasis>
Nothing is using this recipe in OpenEmbedded-Core
(i.e. <filename>meta-oe</filename>).
</para></listitem>
<listitem><para>
<emphasis><filename>python-six</filename>:</emphasis>
This recipe was removed in favor of the Python 3 version.
</para></listitem>
<listitem><para>
<emphasis><filename>python-smmap</filename>:</emphasis>
This recipe was removed in favor of the Python 3 version.
</para></listitem>
<listitem><para>
<emphasis><filename>remake</filename>:</emphasis>
Using <filename>remake</filename> as the provider of
<filename>virtual/make</filename> is broken.
Consequently, this recipe is not needed in OpenEmbedded-Core.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.4-kernel-device-tree-move'>
<title>Kernel Device Tree Move</title>
<para>
Kernel Device Tree support is now easier to enable in a kernel
recipe.
The Device Tree code has moved to a
<link linkend='ref-classes-kernel-devicetree'><filename>kernel-devicetree</filename></link>
class.
Functionality is automatically enabled for any recipe that inherits
the
<link linkend='ref-classes-kernel'><filename>kernel</filename></link>
class and sets the
<link linkend='var-KERNEL_DEVICETREE'><filename>KERNEL_DEVICETREE</filename></link>
variable.
The previous mechanism for doing this,
<filename>meta/recipes-kernel/linux/linux-dtb.inc</filename>,
is still available to avoid breakage, but triggers a
deprecation warning.
Future releases of the Yocto Project will remove
<filename>meta/recipes-kernel/linux/linux-dtb.inc</filename>.
It is advisable to remove any <filename>require</filename>
statements that request
<filename>meta/recipes-kernel/linux/linux-dtb.inc</filename>
from any custom kernel recipes you might have.
This will avoid breakage in post 2.4 releases.
</para>
</section>
<section id='migration-2.4-package-qa-changes'>
<title>Package QA Changes</title>
<para>
The following package QA changes took place:
<itemizedlist>
<listitem><para>
The "unsafe-references-in-scripts" QA check has been
removed.
</para></listitem>
<listitem><para>
If you refer to <filename>${COREBASE}/LICENSE</filename>
within
<link linkend='var-LIC_FILES_CHKSUM'><filename>LIC_FILES_CHKSUM</filename></link>
you receive a warning because this file is a description of
the license for OE-Core.
Use <filename>${COMMON_LICENSE_DIR}/MIT</filename>
if your recipe is MIT-licensed and you cannot use the
preferred method of referring to a file within the source
tree.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.4-readme-changes'>
<title><filename>README</filename> File Changes</title>
<para>
The following are changes to <filename>README</filename> files:
<itemizedlist>
<listitem><para>
The main Poky <filename>README</filename> file has been
moved to the <filename>meta-poky</filename> layer and
has been renamed <filename>README.poky</filename>.
A symlink has been created so that references to the old
location work.
</para></listitem>
<listitem><para>
The <filename>README.hardware</filename> file has been moved
to <filename>meta-yocto-bsp</filename>.
A symlink has been created so that references to the old
location work.
</para></listitem>
<listitem><para>
A <filename>README.qemu</filename> file has been created
with coverage of the <filename>qemu*</filename> machines.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.4-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following are additional changes:
<itemizedlist>
<listitem><para>
The <filename>ROOTFS_PKGMANAGE_BOOTSTRAP</filename>
variable and any references to it have been removed.
You should remove this variable from any custom recipes.
</para></listitem>
<listitem><para>
The <filename>meta-yocto</filename> directory has been
removed.
<note>
In the Yocto Project 2.1 release
<filename>meta-yocto</filename> was renamed to
<filename>meta-poky</filename> and the
<filename>meta-yocto</filename> subdirectory remained
to avoid breaking existing configurations.
</note>
</para></listitem>
<listitem><para>
The <filename>maintainers.inc</filename> file, which tracks
maintainers by listing a primary person responsible for each
recipe in OE-Core, has been moved from
<filename>meta-poky</filename> to OE-Core (i.e. from
<filename>meta-poky/conf/distro/include</filename> to
<filename>meta/conf/distro/include</filename>).
</para></listitem>
<listitem><para>
The
<link linkend='ref-classes-buildhistory'><filename>buildhistory</filename></link>
class now makes a single commit per build rather than one
commit per subdirectory in the repository.
This behavior assumes the commits are enabled with
<link linkend='var-BUILDHISTORY_COMMIT'><filename>BUILDHISTORY_COMMIT</filename></link>
= "1", which is typical.
Previously, the <filename>buildhistory</filename> class made
one commit per subdirectory in the repository in order to
make it easier to see the changes for a particular
subdirectory.
To view a particular change, specify that subdirectory as
the last parameter on the <filename>git show</filename>
or <filename>git diff</filename> commands.
</para></listitem>
<listitem><para>
The <filename>x86-base.inc</filename> file, which is
included by all x86-based machine configurations, now sets
<link linkend='var-IMAGE_FSTYPES'><filename>IMAGE_FSTYPES</filename></link>
using <filename>?=</filename> to "live" rather than
appending with <filename>+=</filename>.
This change makes the default easier to override.
</para></listitem>
<listitem><para>
BitBake fires multiple "BuildStarted" events when
multiconfig is enabled (one per configuration).
For more information, see the
"<ulink url='&YOCTO_DOCS_BB_URL;#events'>Events</ulink>"
section in the BitBake User Manual.
</para></listitem>
<listitem><para>
By default, the <filename>security_flags.inc</filename> file
sets a
<link linkend='var-GCCPIE'><filename>GCCPIE</filename></link>
variable with an option to enable Position Independent
Executables (PIE) within <filename>gcc</filename>.
Enabling PIE in the GNU C Compiler (GCC), makes Return
Oriented Programming (ROP) attacks much more difficult to
execute.
</para></listitem>
<listitem><para>
OE-Core now provides a
<filename>bitbake-layers</filename> plugin that implements
a "create-layer" subcommand.
The implementation of this subcommand has resulted in the
<filename>yocto-layer</filename> script being deprecated and
will likely be removed in the next Yocto Project release.
</para></listitem>
<listitem><para>
The <filename>vmdk</filename>, <filename>vdi</filename>,
and <filename>qcow2</filename> image file types are now
used in conjunction with the "wic" image type through
<filename>CONVERSION_CMD</filename>.
Consequently, the equivalent image types are now
<filename>wic.vmdk</filename>, <filename>wic.vdi</filename>,
and <filename>wic.qcow2</filename>, respectively.
</para></listitem>
<listitem><para>
<filename>do_image_&lt;type&gt;[depends]</filename> has
replaced <filename>IMAGE_DEPENDS_&lt;type&gt;</filename>.
If you have your own classes that implement custom image
types, then you need to update them.
</para></listitem>
<listitem><para>
OpenSSL 1.1 has been introduced.
However, the default is still 1.0.x through the
<link linkend='var-PREFERRED_VERSION'><filename>PREFERRED_VERSION</filename></link>
variable.
This preference is set is due to the remaining compatibility
issues with other software.
The
<link linkend='var-PROVIDES'><filename>PROVIDES</filename></link>
variable in the openssl 1.0 recipe now includes "openssl10"
as a marker that can be used in
<link linkend='var-DEPENDS'><filename>DEPENDS</filename></link>
within recipes that build software that still depend on
OpenSSL 1.0.
</para></listitem>
<listitem><para>
To ensure consistent behavior, BitBake's "-r" and "-R"
options (i.e. prefile and postfile), which are used to
read or post-read additional configuration files from the
command line, now only affect the current BitBake command.
Before these BitBake changes, these options would "stick"
for future executions.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.5-release'>
<title>Moving to the Yocto Project 2.5 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.5 Release from the prior release.
</para>
<section id='migration-2.5-packaging-changes'>
<title>Packaging Changes</title>
<para>
This section provides information about packaging changes that have
occurred:
<itemizedlist>
<listitem><para>
<emphasis><filename>bind-libs</filename>:</emphasis>
The libraries packaged by the bind recipe are in a
separate <filename>bind-libs</filename> package.
</para></listitem>
<listitem><para>
<emphasis><filename>libfm-gtk</filename>:</emphasis>
The <filename>libfm</filename> GTK+ bindings are split into
a separate <filename>libfm-gtk</filename> package.
</para></listitem>
<listitem><para>
<emphasis><filename>flex-libfl</filename>:</emphasis>
The flex recipe splits out libfl into a separate
<filename>flex-libfl</filename> package to avoid too many
dependencies being pulled in where only the library is
needed.
</para></listitem>
<listitem><para>
<emphasis><filename>grub-efi</filename>:</emphasis>
The <filename>grub-efi</filename> configuration is split
into a separate <filename>grub-bootconf</filename>
recipe.
However, the dependency relationship from
<filename>grub-efi</filename> is through a
virtual/grub-bootconf provider making it possible to have
your own recipe provide the dependency.
Alternatively, you can use a BitBake append file to bring
the configuration back into the
<filename>grub-efi</filename> recipe.
</para></listitem>
<listitem><para>
<emphasis>armv7a Legacy Package Feed Support:</emphasis>
Legacy support is removed for transitioning from
<filename>armv7a</filename> to
<filename>armv7a-vfp-neon</filename> in package feeds,
which was previously enabled by setting
<filename>PKGARCHCOMPAT_ARMV7A</filename>.
This transition occurred in 2011 and active package feeds
should by now be updated to the new naming.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.5-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para>
<emphasis><filename>gcc</filename>:</emphasis>
The version 6.4 recipes are replaced by 7.x.
</para></listitem>
<listitem><para>
<emphasis><filename>gst-player</filename>:</emphasis>
Renamed to <filename>gst-examples</filename> as per
upstream.
</para></listitem>
<listitem><para>
<emphasis><filename>hostap-utils</filename>:</emphasis>
This software package is obsolete.
</para></listitem>
<listitem><para>
<emphasis><filename>latencytop</filename>:</emphasis>
This recipe is no longer maintained upstream.
The last release was in 2009.
</para></listitem>
<listitem><para>
<emphasis><filename>libpfm4</filename>:</emphasis>
The only file that requires this recipe is
<filename>oprofile</filename>, which has been removed.
</para></listitem>
<listitem><para>
<emphasis><filename>linux-yocto</filename>:</emphasis>
The version 4.4, 4.9, and 4.10 recipes have been removed.
Versions 4.12, 4.14, and 4.15 remain.
</para></listitem>
<listitem><para>
<emphasis><filename>man</filename>:</emphasis>
This recipe has been replaced by modern
<filename>man-db</filename>
</para></listitem>
<listitem><para>
<emphasis><filename>mkelfimage</filename>:</emphasis>
This tool has been removed in the upstream coreboot project,
and is no longer needed with the removal of the ELF image
type.
</para></listitem>
<listitem><para>
<emphasis><filename>nativesdk-postinst-intercept</filename>:</emphasis>
This recipe is not maintained.
</para></listitem>
<listitem><para>
<emphasis><filename>neon</filename>:</emphasis>
This software package is no longer maintained upstream and
is no longer needed by anything in OpenEmbedded-Core.
</para></listitem>
<listitem><para>
<emphasis><filename>oprofile</filename>:</emphasis>
The functionality of this recipe is replaced by
<filename>perf</filename> and keeping compatibility on
an ongoing basis with <filename>musl</filename> is
difficult.
</para></listitem>
<listitem><para>
<emphasis><filename>pax</filename>:</emphasis>
This software package is obsolete.
</para></listitem>
<listitem><para>
<emphasis><filename>stat</filename>:</emphasis>
This software package is not maintained upstream.
<filename>coreutils</filename> provides a modern stat binary.
</para></listitem>
<listitem><para>
<emphasis><filename>zisofs-tools-native</filename>:</emphasis>
This recipe is no longer needed because the compressed
ISO image feature has been removed.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.5-scripts-and-tools-changes'>
<title>Scripts and Tools Changes</title>
<para>
The following are changes to scripts and tools:
<itemizedlist>
<listitem><para>
<emphasis><filename>yocto-bsp</filename>,
<filename>yocto-kernel</filename>, and
<filename>yocto-layer</filename></emphasis>:
The <filename>yocto-bsp</filename>,
<filename>yocto-kernel</filename>, and
<filename>yocto-layer</filename> scripts previously shipped
with poky but not in OpenEmbedded-Core have been removed.
These scripts are not maintained and are outdated.
In many cases, they are also limited in scope.
The <filename>bitbake-layers create-layer</filename> command
is a direct replacement for <filename>yocto-layer</filename>.
See the documentation to create a BSP or kernel recipe in
the
"<ulink url='&YOCTO_DOCS_BSP_URL;#bsp-kernel-recipe-example'>BSP Kernel Recipe Example</ulink>"
section.
</para></listitem>
<listitem><para>
<emphasis><filename>devtool finish</filename>:</emphasis>
<filename>devtool finish</filename> now exits with an error
if there are uncommitted changes or a rebase/am in progress
in the recipe's source repository.
If this error occurs, there might be uncommitted changes
that will not be included in updates to the patches applied
by the recipe.
A -f/--force option is provided for situations that the
uncommitted changes are inconsequential and you want to
proceed regardless.
</para></listitem>
<listitem><para>
<emphasis><filename>scripts/oe-setup-rpmrepo</filename> script:</emphasis>
The functionality of
<filename>scripts/oe-setup-rpmrepo</filename> is replaced by
<filename>bitbake package-index</filename>.
</para></listitem>
<listitem><para>
<emphasis><filename>scripts/test-dependencies.sh</filename> script:</emphasis>
The script is largely made obsolete by the
recipe-specific sysroots functionality introduced in the
previous release.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.5-bitbake-changes'>
<title>BitBake Changes</title>
<para>
The following are BitBake changes:
<itemizedlist>
<listitem><para>
The <filename>--runall</filename> option has changed.
There are two different behaviors people might want:
<itemizedlist>
<listitem><para>
<emphasis>Behavior A:</emphasis>
For a given target (or set of targets) look through
the task graph and run task X only if it is present
and will be built.
</para></listitem>
<listitem><para>
<emphasis>Behavior B:</emphasis>
For a given target (or set of targets) look through
the task graph and run task X if any recipe in the
taskgraph has such a target, even if it is not in
the original task graph.
</para></listitem>
</itemizedlist>
The <filename>--runall</filename> option now performs
"Behavior B".
Previously <filename>--runall</filename> behaved like
"Behavior A".
A <filename>--runonly</filename> option has been added to
retain the ability to perform "Behavior A".
</para></listitem>
<listitem><para>
Several explicit "run this task for all recipes in the
dependency tree" tasks have been removed (e.g.
<filename>fetchall</filename>,
<filename>checkuriall</filename>, and the
<filename>*all</filename> tasks provided by the
<filename>distrodata</filename> and
<filename>archiver</filename> classes).
There is a BitBake option to complete this for any arbitrary
task. For example:
<literallayout class='monospaced'>
bitbake &lt;target&gt; -c fetchall
</literallayout>
should now be replaced with:
<literallayout class='monospaced'>
bitbake &lt;target&gt; --runall=fetch
</literallayout>
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.5-python-and-python3-changes'>
<title>Python and Python 3 Changes</title>
<para>
The following are auto-packaging changes to Python and Python 3:
</para>
<para>
The script-managed <filename>python-*-manifest.inc</filename> files
that were previously used to generate Python and Python 3
packages have been replaced with a JSON-based file that is
easier to read and maintain.
A new task is available for maintainers of the Python recipes to
update the JSON file when upgrading to new Python versions.
You can now edit the file directly instead of having to edit a
script and run it to update the file.
</para>
<para>
One particular change to note is that the Python recipes no longer
have build-time provides for their packages.
This assumes <filename>python-foo</filename> is one of the packages
provided by the Python recipe.
You can no longer run <filename>bitbake python-foo</filename> or
have a <ulink url='&YOCTO_DOCS_REF_URL;#var-DEPENDS'><filename>DEPENDS</filename></ulink> on
<filename>python-foo</filename>, but doing either of the following
causes the package to work as expected:
<literallayout class='monospaced'>
IMAGE_INSTALL_append = " python-foo"
</literallayout>
or
<literallayout class='monospaced'>
RDEPENDS_${PN} = "python-foo"
</literallayout>
The earlier build-time provides behavior was a quirk of the way the
Python manifest file was created.
For more information on this change please see
<ulink url='http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=8d94b9db221d1def42f091b991903faa2d1651ce'>this commit</ulink>.
</para>
</section>
<section id='migration-2.5-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following are additional changes:
<itemizedlist>
<listitem><para>
The <filename>kernel</filename> class supports building
packages for multiple kernels.
If your kernel recipe or <filename>.bbappend</filename> file
mentions packaging at all, you should replace references to
the kernel in package names with
<filename>${KERNEL_PACKAGE_NAME}</filename>.
For example, if you disable automatic installation of the
kernel image using
<filename>RDEPENDS_kernel-base = ""</filename> you can avoid
warnings using
<filename>RDEPENDS_${KERNEL_PACKAGE_NAME}-base = ""</filename>
instead.
</para></listitem>
<listitem><para>
The <filename>buildhistory</filename> class commits changes
to the repository by default so you no longer need to set
<filename>BUILDHISTORY_COMMIT = "1"</filename>.
If you want to disable commits you need to set
<filename>BUILDHISTORY_COMMIT = "0"</filename> in your
configuration.
</para></listitem>
<listitem><para>
The <filename>beaglebone</filename> reference machine has
been renamed to <filename>beaglebone-yocto</filename>.
The <filename>beaglebone-yocto</filename> BSP is a reference
implementation using only mainline components available in
OpenEmbedded-Core and <filename>meta-yocto-bsp</filename>,
whereas Texas Instruments maintains a full-featured BSP in
the <filename>meta-ti</filename> layer.
This rename avoids the previous name clash that existed
between the two BSPs.
</para></listitem>
<listitem><para>
The <filename>update-alternatives</filename> class no longer
works with SysV <filename>init</filename> scripts because
this usage has been problematic.
Also, the <filename>sysklogd</filename> recipe no longer
uses <filename>update-alternatives</filename> because it is
incompatible with other implementations.
</para></listitem>
<listitem><para>
By default, the
<link linkend='ref-classes-cmake'><filename>cmake</filename></link>
class uses <filename>ninja</filename> instead of
<filename>make</filename> for building.
This improves build performance.
If a recipe is broken with <filename>ninja</filename>, then
the recipe can set
<filename>OECMAKE_GENERATOR = "Unix Makefiles"</filename>
to change back to <filename>make</filename>.
</para></listitem>
<listitem><para>
The previously deprecated <filename>base_*</filename>
functions have been removed in favor of their replacements
in <filename>meta/lib/oe</filename> and
<filename>bitbake/lib/bb</filename>.
These are typically used from recipes and classes.
Any references to the old functions must be updated.
The following table shows the removed functions and their
replacements:
<literallayout class='monospaced'>
<emphasis>Removed</emphasis> <emphasis>Replacement</emphasis>
============================ ============================
base_path_join() oe.path.join()
base_path_relative() oe.path.relative()
base_path_out() oe.path.format_display()
base_read_file() oe.utils.read_file()
base_ifelse() oe.utils.ifelse()
base_conditional() oe.utils.conditional()
base_less_or_equal() oe.utils.less_or_equal()
base_version_less_or_equal() oe.utils.version_less_or_equal()
base_contains() bb.utils.contains()
base_both_contain() oe.utils.both_contain()
base_prune_suffix() oe.utils.prune_suffix()
oe_filter() oe.utils.str_filter()
oe_filter_out() oe.utils.str_filter_out() (or use the _remove operator).
</literallayout>
</para></listitem>
<listitem><para>
Using <filename>exit 1</filename> to explicitly defer a
postinstall script until first boot is now deprecated since
it is not an obvious mechanism and can mask actual errors.
If you want to explicitly defer a postinstall to first boot
on the target rather than at <filename>rootfs</filename>
creation time, use
<filename>pkg_postinst_ontarget()</filename>
or call
<filename>postinst_intercept delay_to_first_boot</filename>
from <filename>pkg_postinst()</filename>.
Any failure of a <filename>pkg_postinst()</filename>
script (including <filename>exit 1</filename>)
will trigger a warning during
<filename>do_rootfs</filename>.</para>
<para>For more information, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#new-recipe-post-installation-scripts'>Post-Installation Scripts</ulink>"
section in the Yocto Project Development Tasks Manual.
</para></listitem>
<listitem><para>
The <filename>elf</filename> image type has been removed.
This image type was removed because the
<filename>mkelfimage</filename> tool
that was required to create it is no longer provided by
coreboot upstream and required updating every time
<filename>binutils</filename> updated.
</para></listitem>
<listitem><para>
Support for .iso image compression (previously enabled
through <filename>COMPRESSISO = "1"</filename>) has been
removed.
The userspace tools (<filename>zisofs-tools</filename>) are
unmaintained and <filename>squashfs</filename> provides
better performance and compression.
In order to build a live image with squashfs+lz4 compression
enabled you should now set
<filename>LIVE_ROOTFS_TYPE = "squashfs-lz4"</filename>
and ensure that <filename>live</filename>
is in <filename>IMAGE_FSTYPES</filename>.
</para></listitem>
<listitem><para>
Recipes with an unconditional dependency on
<filename>libpam</filename> are only buildable with
<filename>pam</filename> in
<filename>DISTRO_FEATURES</filename>.
If the dependency is truly optional then it is recommended
that the dependency be conditional upon
<filename>pam</filename> being in
<filename>DISTRO_FEATURES</filename>.
</para></listitem>
<listitem><para>
For EFI-based machines, the bootloader
(<filename>grub-efi</filename> by default) is installed into
the image at /boot.
Wic can be used to split the bootloader into separate boot
and rootfs partitions if necessary.
</para></listitem>
<listitem><para>
Patches whose context does not match exactly (i.e. where
patch reports "fuzz" when applying) will generate a
warning.
For an example of this see
<ulink url='http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=cc97bc08125b63821ce3f616771830f77c456f57'>this commit</ulink>.
</para></listitem>
<listitem><para>
Layers are expected to set
<filename>LAYERSERIES_COMPAT_layername</filename>
to match the version(s) of OpenEmbedded-Core they are
compatible with.
This is specified as codenames using spaces to separate
multiple values (e.g. "rocko sumo").
If a layer does not set
<filename>LAYERSERIES_COMPAT_layername</filename>, a warning
will is shown.
If a layer sets a value that does not include the current
version ("sumo" for the 2.5 release), then an error will be
produced.
</para></listitem>
<listitem><para>
The <filename>TZ</filename> environment variable is set to
"UTC" within the build environment in order to fix
reproducibility problems in some recipes.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.6-release'>
<title>Moving to the Yocto Project 2.6 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.6 Release from the prior release.
</para>
<section id='migration-2.6-gcc-changes'>
<title>GCC 8.2 is Now Used by Default</title>
<para>
The GNU Compiler Collection version 8.2 is now used by default
for compilation.
For more information on what has changed in the GCC 8.x release,
see
<ulink url='https://gcc.gnu.org/gcc-8/changes.html'></ulink>.
</para>
<para>
If you still need to compile with version 7.x, GCC 7.3 is
also provided.
You can select this version by setting the
and can be selected by setting the
<link linkend='var-GCCVERSION'><filename>GCCVERSION</filename></link>
variable to "7.%" in your configuration.
</para>
</section>
<section id='migration-2.6-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<literallayout class='monospaced'>
<emphasis><filename>beecrypt</filename>:</emphasis> No longer needed since moving to RPM 4.
<emphasis><filename>bigreqsproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>calibrateproto</filename>:</emphasis> Removed in favor of <filename>xinput</filename>.
<emphasis><filename>compositeproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>damageproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>dmxproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>dri2proto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>dri3proto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>eee-acpi-scripts</filename>:</emphasis> Became obsolete.
<emphasis><filename>fixesproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>fontsproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>fstests</filename>:</emphasis> Became obsolete.
<emphasis><filename>gccmakedep</filename>:</emphasis> No longer used.
<emphasis><filename>glproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>gnome-desktop3</filename>:</emphasis> No longer needed. This recipe has moved to <filename>meta-oe</filename>.
<emphasis><filename>icon-naming-utils</filename>:</emphasis> No longer used since the Sato theme was removed in 2016.
<emphasis><filename>inputproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>kbproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>libusb-compat</filename>:</emphasis> Became obsolete.
<emphasis><filename>libuser</filename>:</emphasis> Became obsolete.
<emphasis><filename>libnfsidmap</filename>:</emphasis> No longer an external requirement since <filename>nfs-utils</filename> 2.2.1. <filename>libnfsidmap</filename> is now integrated.
<emphasis><filename>libxcalibrate</filename>:</emphasis> No longer needed with <filename>xinput</filename>
<emphasis><filename>mktemp</filename>:</emphasis> Became obsolete. The <filename>mktemp</filename> command is provided by both <filename>busybox</filename> and <filename>coreutils</filename>.
<emphasis><filename>ossp-uuid</filename>:</emphasis> Is not being maintained and has mostly been replaced by <filename>uuid.h</filename> in <filename>util-linux</filename>.
<emphasis><filename>pax-utils</filename>:</emphasis> No longer needed. Previous QA tests that did use this recipe are now done at build time.
<emphasis><filename>pcmciautils</filename>:</emphasis> Became obsolete.
<emphasis><filename>pixz</filename>:</emphasis> No longer needed. <filename>xz</filename> now supports multi-threaded compression.
<emphasis><filename>presentproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>randrproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>recordproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>renderproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>resourceproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>scrnsaverproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>trace-cmd</filename>:</emphasis> Became obsolete. <filename>perf</filename> replaced this recipe's functionally.
<emphasis><filename>videoproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>wireless-tools</filename>:</emphasis> Became obsolete. Superseded by <filename>iw</filename>.
<emphasis><filename>xcmiscproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>xextproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>xf86dgaproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>xf86driproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>xf86miscproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>xf86-video-omapfb</filename>:</emphasis> Became obsolete. Use kernel modesetting driver instead.
<emphasis><filename>xf86-video-omap</filename>:</emphasis> Became obsolete. Use kernel modesetting driver instead.
<emphasis><filename>xf86vidmodeproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>xineramaproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>xproto</filename>:</emphasis> Replaced by <filename>xorgproto</filename>.
<emphasis><filename>yasm</filename>:</emphasis> No longer needed since previous usages are now satisfied by <filename>nasm</filename>.
</literallayout>
</para>
</section>
<section id='migration-2.6-packaging-changes'>
<title>Packaging Changes</title>
<para>
The following packaging changes have been made:
<itemizedlist>
<listitem><para>
<emphasis><filename>cmake</filename>:</emphasis>
<filename>cmake.m4</filename> and
<filename>toolchain</filename> files have been moved to the
main package.
</para></listitem>
<listitem><para>
<emphasis><filename>iptables</filename>:</emphasis>
The <filename>iptables</filename> modules have been split
into separate packages.
</para></listitem>
<listitem><para>
<emphasis><filename>alsa-lib</filename>:</emphasis>
<filename>libasound</filename> is now in the main
<filename>alsa-lib</filename> package instead of
<filename>libasound</filename>.
</para></listitem>
<listitem><para>
<emphasis><filename>glibc</filename>:</emphasis>
<filename>libnss-db</filename> is now in its own package
along with a <filename>/var/db/makedbs.sh</filename>
script to update databases.
</para></listitem>
<listitem><para>
<emphasis><filename>python</filename> and <filename>python3</filename>:</emphasis>
The main package has been removed from the recipe.
You must install specific packages or
<filename>python-modules</filename> /
<filename>python3-modules</filename> for everything.
</para></listitem>
<listitem><para>
<emphasis><filename>systemtap</filename>:</emphasis>
Moved <filename>systemtap-exporter</filename> into its own
package.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.6-xorg-protocol-dependencies'>
<title>XOrg Protocol dependencies</title>
<para>
The "*proto" upstream repositories have been combined into one
"xorgproto" repository.
Thus, the corresponding recipes have also been combined into a
single <filename>xorgproto</filename> recipe.
Any recipes that depend upon the older <filename>*proto</filename>
recipes need to be changed to depend on the newer
<filename>xorgproto</filename> recipe instead.
</para>
<para>
For names of recipes removed because of this repository change,
see the
<link linkend="migration-2.6-removed-recipes">Removed Recipes</link>
section.
</para>
</section>
<section id='migration-2.6-distutils-distutils3-fetching-dependencies'>
<title><filename>distutils</filename> and <filename>distutils3</filename> Now Prevent Fetching Dependencies During the <filename>do_configure</filename> Task</title>
<para>
Previously, it was possible for Python recipes that inherited
the
<link linkend='ref-classes-distutils'><filename>distutils</filename></link>
and
<link linkend='ref-classes-distutils3'><filename>distutils3</filename></link>
classes to fetch code during the
<link linkend='ref-tasks-configure'><filename>do_configure</filename></link>
task to satisfy dependencies mentioned in
<filename>setup.py</filename> if those dependencies were not
provided in the sysroot (i.e. recipes providing the dependencies
were missing from
<link linkend='var-DEPENDS'><filename>DEPENDS</filename></link>).
<note>
This change affects classes beyond just the two mentioned
(i.e. <filename>distutils</filename> and
<filename>distutils3</filename>).
Any recipe that inherits <filename>distutils*</filename>
classes are affected.
For example, the <filename>setuptools</filename> and
<filename>setuptools3</filename> recipes are affected since
they inherit the <filename>distutils*</filename> classes.
</note>
</para>
<para>
Fetching these types of dependencies that are not provided in the
sysroot negatively affects the ability to reproduce builds.
This type of fetching is now explicitly disabled.
Consequently, any missing dependencies in Python recipes that
use these classes now result in an error during the
<filename>do_configure</filename> task.
</para>
</section>
<section id='migration-2.6-linux-yocto-configuration-audit-issues-now-correctly-reported'>
<title><filename>linux-yocto</filename> Configuration Audit Issues Now Correctly Reported</title>
<para>
Due to a bug, the kernel configuration audit functionality was
not writing out any resulting warnings during the build.
This issue is now corrected.
You might notice these warnings now if you have a custom kernel
configuration with a <filename>linux-yocto</filename> style
kernel recipe.
</para>
</section>
<section id='migration-2.6-image-kernel-artifact-naming-changes'>
<title>Image/Kernel Artifact Naming Changes</title>
<para>
The following changes have been made:
<itemizedlist>
<listitem><para>
Name variables (e.g.
<link linkend='var-IMAGE_NAME'><filename>IMAGE_NAME</filename></link>)
use a new <filename>IMAGE_VERSION_SUFFIX</filename>
variable instead of
<link linkend='var-DATETIME'><filename>DATETIME</filename></link>.
Using <filename>IMAGE_VERSION_SUFFIX</filename> allows
easier and more direct changes.</para>
<para>The <filename>IMAGE_VERSION_SUFFIX</filename>
variable is set in the
<filename>bitbake.conf</filename> configuration file as
follows:
<literallayout class='monospaced'>
IMAGE_VERSION_SUFFIX = "-${DATETIME}"
</literallayout>
</para></listitem>
<listitem><para>
Several variables have changed names for consistency:
<literallayout class='monospaced'>
Old Variable Name New Variable Name
========================================================
KERNEL_IMAGE_BASE_NAME <link linkend='var-KERNEL_IMAGE_NAME'>KERNEL_IMAGE_NAME</link>
KERNEL_IMAGE_SYMLINK_NAME <link linkend='var-KERNEL_IMAGE_LINK_NAME'>KERNEL_IMAGE_LINK_NAME</link>
MODULE_TARBALL_BASE_NAME <link linkend='var-MODULE_TARBALL_NAME'>MODULE_TARBALL_NAME</link>
MODULE_TARBALL_SYMLINK_NAME <link linkend='var-MODULE_TARBALL_LINK_NAME'>MODULE_TARBALL_LINK_NAME</link>
INITRAMFS_BASE_NAME <link linkend='var-INITRAMFS_NAME'>INITRAMFS_NAME</link>
</literallayout>
</para></listitem>
<listitem><para>
The <filename>MODULE_IMAGE_BASE_NAME</filename> variable
has been removed.
The module tarball name is now controlled directly with the
<link linkend='var-MODULE_TARBALL_NAME'><filename>MODULE_TARBALL_NAME</filename></link>
variable.
</para></listitem>
<listitem><para>
The
<link linkend='var-KERNEL_DTB_NAME'><filename>KERNEL_DTB_NAME</filename></link>
and
<link linkend='var-KERNEL_DTB_LINK_NAME'><filename>KERNEL_DTB_LINK_NAME</filename></link>
variables have been introduced to control kernel Device
Tree Binary (DTB) artifact names instead of mangling
<filename>KERNEL_IMAGE_*</filename> variables.
</para></listitem>
<listitem><para>
The
<link linkend='var-KERNEL_FIT_NAME'><filename>KERNEL_FIT_NAME</filename></link>
and
<link linkend='var-KERNEL_FIT_LINK_NAME'><filename>KERNEL_FIT_LINK_NAME</filename></link>
variables have been introduced to specify the name of
flattened image tree (FIT) kernel images similar to other
deployed artifacts.
</para></listitem>
<listitem><para>
The
<link linkend='var-MODULE_TARBALL_NAME'><filename>MODULE_TARBALL_NAME</filename></link>
and
<link linkend='var-MODULE_TARBALL_LINK_NAME'><filename>MODULE_TARBALL_LINK_NAME</filename></link>
variable values no longer include the "module-" prefix or
".tgz" suffix.
These parts are now hardcoded so that the values are
consistent with other artifact naming variables.
</para></listitem>
<listitem><para>
Added the
<link linkend='var-INITRAMFS_LINK_NAME'><filename>INITRAMFS_LINK_NAME</filename></link>
variable so that the symlink can be controlled similarly
to other artifact types.
</para></listitem>
<listitem><para>
<link linkend='var-INITRAMFS_NAME'><filename>INITRAMFS_NAME</filename></link>
now uses
"${PKGE}-${PKGV}-${PKGR}-${MACHINE}${IMAGE_VERSION_SUFFIX}"
instead of
"${PV}-${PR}-${MACHINE}-${DATETIME}", which
makes it consistent with other variables.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.6-serial-console-deprecated'>
<title><filename>SERIAL_CONSOLE</filename> Deprecated</title>
<para>
The
<link linkend='var-SERIAL_CONSOLE'><filename>SERIAL_CONSOLE</filename></link>
variable has been functionally replaced by the
<link linkend='var-SERIAL_CONSOLES'><filename>SERIAL_CONSOLES</filename></link>
variable for some time.
With the Yocto Project 2.6 release,
<filename>SERIAL_CONSOLE</filename> has been officially deprecated.
</para>
<para>
<filename>SERIAL_CONSOLE</filename> will continue to work as
before for the 2.6 release.
However, for the sake of future compatibility, it is recommended
that you replace all instances of
<filename>SERIAL_CONSOLE</filename> with
<filename>SERIAL_CONSOLES</filename>.
<note>
The only difference in usage is that
<filename>SERIAL_CONSOLES</filename> expects entries to be
separated using semicolons as compared to
<filename>SERIAL_CONSOLE</filename>, which expects spaces.
</note>
</para>
</section>
<section id='migration-2.6-poky-sets-unknown-configure-option-to-qa-error'>
<title>Configure Script Reports Unknown Options as Errors</title>
<para>
If the configure script reports an unknown option, this now
triggers a QA error instead of a warning.
Any recipes that previously got away with specifying such unknown
options now need to be fixed.
</para>
</section>
<section id='migration-2.6-override-changes'>
<title>Override Changes</title>
<para>
The following changes have occurred:
<itemizedlist>
<listitem><para>
<emphasis>The <filename>virtclass-native</filename> and
<filename>virtclass-nativesdk</filename> Overrides Have
Been Removed:</emphasis>
The <filename>virtclass-native</filename> and
<filename>virtclass-nativesdk</filename> overrides have
been deprecated since 2012 in favor of
<filename>class-native</filename> and
<filename>class-nativesdk</filename>, respectively.
Both <filename>virtclass-native</filename> and
<filename>virtclass-nativesdk</filename> are now dropped.
<note>
The <filename>virtclass-multilib-</filename> overrides
for multilib are still valid.
</note>
</para></listitem>
<listitem><para>
<emphasis>The <filename>forcevariable</filename>
Override Now Has a Higher Priority Than
<filename>libc</filename> Overrides:</emphasis>
The <filename>forcevariable</filename> override is
documented to be the highest priority override.
However, due to a long-standing quirk of how
<link linkend='var-OVERRIDES'><filename>OVERRIDES</filename></link>
is set, the <filename>libc</filename> overrides (e.g.
<filename>libc-glibc</filename>,
<filename>libc-musl</filename>, and so forth) erroneously
had a higher priority.
This issue is now corrected.</para>
<para>It is likely this change will not cause any
problems.
However, it is possible with some unusual configurations
that you might see a change in behavior if you were
relying on the previous behavior.
Be sure to check how you use
<filename>forcevariable</filename> and
<filename>libc-*</filename> overrides in your custom
layers and configuration files to ensure they make sense.
</para></listitem>
<listitem><para>
<emphasis>The <filename>build-${BUILD_OS}</filename>
Override Has Been Removed:</emphasis>
The <filename>build-${BUILD_OS}</filename>, which is
typically <filename>build-linux</filename>, override has
been removed because building on a host operating system
other than a recent version of Linux is neither supported
nor recommended.
Dropping the override avoids giving the impression that
other host operating systems might be supported.
</para></listitem>
<listitem><para>
The "_remove" operator now preserves whitespace.
Consequently, when specifying list items to remove, be
aware that leading and trailing whitespace resulting from
the removal is retained.</para>
<para>See the
"<ulink url='&YOCTO_DOCS_BB_URL;#removing-override-style-syntax'>Removal (Override Style Syntax)</ulink>"
section in the BitBake User Manual for a detailed example.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.6-systemd-configuration-now-split-out-to-system-conf'>
<title><filename>systemd</filename> Configuration is Now Split Into <filename>systemd-conf</filename></title>
<para>
The configuration for the <filename>systemd</filename> recipe
has been moved into a <filename>system-conf</filename> recipe.
Moving this configuration to a separate recipe avoids the
<filename>systemd</filename> recipe from becoming machine-specific
for cases where machine-specific configurations need to be applied
(e.g. for <filename>qemu*</filename> machines).
</para>
<para>
Currently, the new recipe packages the following files:
<literallayout class='monospaced'>
${sysconfdir}/machine-id
${sysconfdir}/systemd/coredump.conf
${sysconfdir}/systemd/journald.conf
${sysconfdir}/systemd/logind.conf
${sysconfdir}/systemd/system.conf
${sysconfdir}/systemd/user.conf
</literallayout>
If you previously used bbappend files to append the
<filename>systemd</filename> recipe to change any of the
listed files, you must do so for the
<filename>systemd-conf</filename> recipe instead.
</para>
</section>
<section id='migration-2.6-automatic-testing-changes'>
<title>Automatic Testing Changes</title>
<para>
This section provides information about automatic testing
changes:
<itemizedlist>
<listitem><para>
<emphasis><filename>TEST_IMAGE</filename> Variable Removed:</emphasis>
Prior to this release, you set the
<filename>TEST_IMAGE</filename> variable to "1" to
enable automatic testing for successfully built images.
The <filename>TEST_IMAGE</filename> variable no longer
exists and has been replaced by the
<link linkend='var-TESTIMAGE_AUTO'><filename>TESTIMAGE_AUTO</filename></link>
variable.
</para></listitem>
<listitem><para>
<emphasis>Inheriting the <filename>testimage</filename> and
<filename>testsdk</filename> Classes:</emphasis>
Best practices now dictate that you use the
<link linkend='var-IMAGE_CLASSES'><filename>IMAGE_CLASSES</filename></link>
variable rather than the
<link linkend='var-INHERIT'><filename>INHERIT</filename></link>
variable when you inherit the
<link linkend='ref-classes-testimage*'><filename>testimage</filename></link>
and
<link linkend='ref-classes-testsdk'><filename>testsdk</filename></link>
classes used for automatic testing.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.6-openssl-changes'>
<title>OpenSSL Changes</title>
<para>
<ulink url='https://www.openssl.org/'>OpenSSL</ulink> has been
upgraded from 1.0 to 1.1.
By default, this upgrade could cause problems for recipes that
have both versions in their dependency chains.
The problem is that both versions cannot be installed together
at build time.
<note>
It is possible to have both versions of the library at runtime.
</note>
</para>
</section>
<section id='migration-2.6-bitbake-changes'>
<title>BitBake Changes</title>
<para>
The server logfile <filename>bitbake-cookerdaemon.log</filename> is
now always placed in the
<link linkend='build-directory'>Build Directory</link>
instead of the current directory.
</para>
</section>
<section id='migration-2.6-security-changes'>
<title>Security Changes</title>
<para>
The Poky distribution now uses security compiler flags by
default.
Inclusion of these flags could cause new failures due to stricter
checking for various potential security issues in code.
</para>
</section>
<section id='migration-2.6-post-installation-changes'>
<title>Post Installation Changes</title>
<para>
You must explicitly mark post installs to defer to the target.
If you want to explicitly defer a postinstall to first boot on
the target rather than at rootfs creation time, use
<filename>pkg_postinst_ontarget()</filename> or call
<filename>postinst_intercept delay_to_first_boot</filename> from
<filename>pkg_postinst()</filename>.
Any failure of a <filename>pkg_postinst()</filename> script
(including exit 1) triggers an error during the
<link linkend='ref-tasks-rootfs'><filename>do_rootfs</filename></link> task.
</para>
<para>
For more information on post-installation behavior, see the
"<ulink url='&YOCTO_DOCS_DEV_URL;#new-recipe-post-installation-scripts'>Post-Installation Scripts</ulink>"
section in the Yocto Project Development Tasks Manual.
</para>
</section>
<section id='migration-2.6-python-3-profile-guided-optimizations'>
<title>Python 3 Profile-Guided Optimization</title>
<para>
The <filename>python3</filename> recipe now enables profile-guided
optimization.
Using this optimization requires a little extra build time in
exchange for improved performance on the target at runtime.
Additionally, the optimization is only enabled if the current
<link linkend='var-MACHINE'><filename>MACHINE</filename></link>
has support for user-mode emulation in QEMU (i.e. "qemu-usermode"
is in
<link linkend='var-MACHINE_FEATURES'><filename>MACHINE_FEATURES</filename></link>,
which it is by default).
</para>
<para>
If you wish to disable Python profile-guided optimization
regardless of the value of
<filename>MACHINE_FEATURES</filename>, then ensure that
<link linkend='var-PACKAGECONFIG'><filename>PACKAGECONFIG</filename></link>
for the <filename>python3</filename> recipe does not contain "pgo".
You could accomplish the latter using the following at the
configuration level:
<literallayout class='monospaced'>
PACKAGECONFIG_remove_pn-python3 = "pgo"
</literallayout>
Alternatively, you can set
<filename>PACKAGECONFIG</filename> using an append file for the
<filename>python3</filename> recipe.
</para>
</section>
<section id='migration-2.6-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following miscellaneous changes occurred:
<itemizedlist>
<listitem><para>
Default to using the Thumb-2 instruction set for armv7a
and above.
If you have any custom recipes that build software that
needs to be built with the ARM instruction set, change the
recipe to set the instruction set as follows:
<literallayout class='monospaced'>
ARM_INSTRUCTION_SET = "arm"
</literallayout>
</para></listitem>
<listitem><para>
<filename>run-postinsts</filename> no longer uses
<filename>/etc/*-postinsts</filename> for
<filename>dpkg/opkg</filename> in favor of built-in
postinst support.
RPM behavior remains unchanged.
</para></listitem>
<listitem><para>
The <filename>NOISO</filename> and
<filename>NOHDD</filename> variables are no longer used.
You now control building <filename>*.iso</filename> and
<filename>*.hddimg</filename> image types directly
by using the
<link linkend='var-IMAGE_FSTYPES'><filename>IMAGE_FSTYPES</filename></link>
variable.
</para></listitem>
<listitem><para>
The <filename>scripts/contrib/mkefidisk.sh</filename>
has been removed in favor of Wic.
</para></listitem>
<listitem><para>
<filename>kernel-modules</filename> has been removed from
<link linkend='var-RRECOMMENDS'><filename>RRECOMMENDS</filename></link>
for <filename>qemumips</filename> and
<filename>qemumips64</filename> machines.
Removal also impacts the <filename>x86-base.inc</filename>
file.
<note>
<filename>genericx86</filename> and
<filename>genericx86-64</filename> retain
<filename>kernel-modules</filename> as part of the
<filename>RRECOMMENDS</filename> variable setting.
</note>
</para></listitem>
<listitem><para>
The <filename>LGPLv2_WHITELIST_GPL-3.0</filename>
variable has been removed.
If you are setting this variable in your configuration,
set or append it to the
<filename>WHITELIST_GPL-3.0</filename> variable instead.
</para></listitem>
<listitem><para>
<filename>${ASNEEDED}</filename> is now included in
the
<link linkend='var-TARGET_LDFLAGS'><filename>TARGET_LDFLAGS</filename></link>
variable directly.
The remaining definitions from
<filename>meta/conf/distro/include/as-needed.inc</filename>
have been moved to corresponding recipes.
</para></listitem>
<listitem><para>
Support for DSA host keys has been dropped from the
OpenSSH recipes.
If you are still using DSA keys, you must switch over to a
more secure algorithm as recommended by OpenSSH upstream.
</para></listitem>
<listitem><para>
The <filename>dhcp</filename> recipe now uses the
<filename>dhcpd6.conf</filename> configuration file in
<filename>dhcpd6.service</filename> for IPv6 DHCP rather
than re-using <filename>dhcpd.conf</filename>, which is
now reserved for IPv4.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-2.7-release'>
<title>Moving to the Yocto Project 2.7 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 2.7 Release from the prior release.
</para>
<section id='migration-2.7-bitbake-changes'>
<title>BitBake Changes</title>
<para>
The following changes have been made to BitBake:
<itemizedlist>
<listitem><para>
BitBake now checks anonymous Python functions and pure
Python functions (e.g. <filename>def funcname:</filename>)
in the metadata for tab indentation.
If found, BitBake produces a warning.
</para></listitem>
<listitem><para>
Bitbake now checks
<link linkend='var-BBFILE_COLLECTIONS'><filename>BBFILE_COLLECTIONS</filename></link>
for duplicate entries and triggers an error if any are
found.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.7-eclipse-support-dropped'>
<title><trademark class='trade'>Eclipse</trademark> Support Removed</title>
<para>
Support for the Eclipse IDE has been removed.
Support continues for those releases prior to 2.7 that did include
support.
The 2.7 release does not include the Eclipse Yocto plugin.
</para>
</section>
<section id='migration-2.7-qemu-native-splits-system-and-user-mode-parts'>
<title><filename>qemu-native</filename> Splits the System and User-Mode Parts</title>
<para>
The system and user-mode parts of <filename>qemu-native</filename>
are now split.
<filename>qemu-native</filename> provides the user-mode components
and <filename>qemu-system-native</filename> provides the system
components.
If you have recipes that depend on QEMU's system emulation
functionality at build time, they should now depend upon
<filename>qemu-system-native</filename> instead of
<filename>qemu-native</filename>.
</para>
</section>
<section id='migration-2.7-upstream-tracking.inc-removed'>
<title>The <filename>upstream-tracking.inc</filename> File Has Been Removed</title>
<para>
The previously deprecated <filename>upstream-tracking.inc</filename>
file is now removed.
Any <filename>UPSTREAM_TRACKING*</filename> variables are now set
in the corresponding recipes instead.
</para>
<para>
Remove any references you have to the
<filename>upstream-tracking.inc</filename> file in your
configuration.
</para>
</section>
<section id='migration-2.7-distro-features-libc-removed'>
<title>The <filename>DISTRO_FEATURES_LIBC</filename> Variable Has Been Removed</title>
<para>
The <filename>DISTRO_FEATURES_LIBC</filename> variable is no
longer used.
The ability to configure glibc using kconfig has been removed
for quite some time making the <filename>libc-*</filename> features
set no longer effective.
</para>
<para>
Remove any references you have to
<filename>DISTRO_FEATURES_LIBC</filename> in your own layers.
</para>
</section>
<section id='migration-2.7-license-values'>
<title>License Value Corrections</title>
<para>
The following corrections have been made to the
<link linkend='var-LICENSE'><filename>LICENSE</filename></link>
values set by recipes:
<literallayout class='monospaced'>
<emphasis>socat</emphasis>: Corrected <filename>LICENSE</filename> to be "GPLv2" rather than
"GPLv2+".
<emphasis>libgfortran</emphasis>: Set license to "GPL-3.0-with-GCC-exception".
<emphasis>elfutils</emphasis>: Removed "Elfutils-Exception" and set to "GPLv2" for shared
libraries
</literallayout>
</para>
</section>
<section id='migration-2.7-packaging-changes'>
<title>Packaging Changes</title>
<para>
This section provides information about packaging changes.
<itemizedlist>
<listitem><para>
<filename>bind</filename>: The
<filename>nsupdate</filename> binary has been moved to
the <filename>bind-utils</filename> package.
</para></listitem>
<listitem><para>
Debug split: The default debug split has been changed to
create separate source packages (i.e.
<replaceable>package_name</replaceable><filename>-dbg</filename>
and
<replaceable>package_name</replaceable><filename>-src</filename>).
If you are currently using <filename>dbg-pkgs</filename>
in
<link linkend='var-IMAGE_FEATURES'><filename>IMAGE_FEATURES</filename></link>
to bring in debug symbols and you still need the sources,
you must now also add <filename>src-pkgs</filename> to
<filename>IMAGE_FEATURES</filename>.
Source packages remain in the target portion of the SDK
by default, unless you have set your own value for
<link linkend='var-SDKIMAGE_FEATURES'><filename>SDKIMAGE_FEATURES</filename></link>
that does not include <filename>src-pkgs</filename>.
</para></listitem>
<listitem><para>
Mount all using <filename>util-linux</filename>:
<filename>/etc/default/mountall</filename> has
moved into the -mount sub-package.
</para></listitem>
<listitem><para>
Splitting binaries using <filename>util-linux</filename>:
<filename>util-linux</filename> now splits each binary into
its own package for fine-grained control.
The main <filename>util-linux</filename> package pulls in
the individual binary packages using the
<link linkend='var-RRECOMMENDS'><filename>RRECOMMENDS</filename></link>
and
<link linkend='var-RDEPENDS'><filename>RDEPENDS</filename></link>
variables.
As a result, existing images should not see any changes
assuming
<link linkend='var-NO_RECOMMENDATIONS'><filename>NO_RECOMMENDATIONS</filename></link>
is not set.
</para></listitem>
<listitem><para>
<filename>netbase/base-files</filename>:
<filename>/etc/hosts</filename> has moved from
<filename>netbase</filename> to
<filename>base-files</filename>.
</para></listitem>
<listitem><para>
<filename>tzdata</filename>: The main package has been
converted to an empty meta package that pulls in all
<filename>tzdata</filename> packages by default.
</para></listitem>
<listitem><para>
<filename>lrzsz</filename>: This package has been removed
from <filename>packagegroup-self-hosted</filename> and
<filename>packagegroup-core-tools-testapps</filename>.
The X/Y/ZModem support is less likely to be needed on
modern systems.
If you are relying on these packagegroups to include the
<filename>lrzsz</filename> package in your image, you
now need to explicitly add the package.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-2.7-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed:
<literallayout class='monospaced'>
<emphasis>gcc</emphasis>: Drop version 7.3 recipes. Version 8.3 now remains.
<emphasis>linux-yocto</emphasis>: Drop versions 4.14 and 4.18 recipes. Versions 4.19 and 5.0 remain.
<emphasis>go</emphasis>: Drop version 1.9 recipes. Versions 1.11 and 1.12 remain.
<emphasis>xvideo-tests</emphasis>: Became obsolete.
<emphasis>libart-lgpl</emphasis>: Became obsolete.
<emphasis>gtk-icon-utils-native</emphasis>: These tools are now provided by gtk+3-native
<emphasis>gcc-cross-initial</emphasis>: No longer needed. gcc-cross/gcc-crosssdk is now used instead.
<emphasis>gcc-crosssdk-initial</emphasis>: No longer needed. gcc-cross/gcc-crosssdk is now used instead.
<emphasis>glibc-initial</emphasis>: Removed because the benefits of having it for site_config are
currently outweighed by the cost of building the recipe.
</literallayout>
</para>
</section>
<section id='migration-2.7-removed-classes'>
<title>Removed Classes</title>
<para>
The following classes have been removed:
<literallayout class='monospaced'>
<emphasis>distutils-tools</emphasis>: This class was never used.
<emphasis>bugzilla.bbclass</emphasis>: Became obsolete.
<emphasis>distrodata</emphasis>: This functionally has been replaced by a more modern
tinfoil-based implementation.
</literallayout>
</para>
</section>
<section id='migration-2.7-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following miscellaneous changes occurred:
<itemizedlist>
<listitem><para>
The <filename>distro</filename> subdirectory of the Poky
repository has been removed from the top-level
<filename>scripts</filename> directory.
</para></listitem>
<listitem><para>
Perl now builds for the target using
<ulink url='http://arsv.github.io/perl-cross/'><filename>perl-cross</filename></ulink>
for better maintainability and improved build performance.
This change should not present any problems unless you have
heavily customized your Perl recipe.
</para></listitem>
<listitem><para>
<filename>arm-tunes</filename>: Removed the "-march"
option if mcpu is already added.
</para></listitem>
<listitem><para>
<filename>update-alternatives</filename>: Convert file
renames to
<link linkend='var-PACKAGE_PREPROCESS_FUNCS'><filename>PACKAGE_PREPROCESS_FUNCS</filename></link>
</para></listitem>
<listitem><para>
<filename>base/pixbufcache</filename>: Obsolete
<filename>sstatecompletions</filename> code has been
removed.
</para></listitem>
<listitem><para>
<link linkend='ref-classes-native'><filename>native</filename></link>
class:
<link linkend='var-RDEPENDS'><filename>RDEPENDS</filename></link>
handling has been enabled.
</para></listitem>
<listitem><para>
<filename>inetutils</filename>: This recipe has rsh
disabled.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-3.0-release'>
<title>Moving to the Yocto Project 3.0 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 3.0 Release from the prior release.
</para>
<section id='migration-3.0-init-system-selection'>
<title>Init System Selection</title>
<para>
Changing the init system manager previously required setting a
number of different variables.
You can now change the manager by setting the
<filename>INIT_MANAGER</filename> variable and the corresponding
include files
(i.e. <filename>conf/distro/include/init-manager-*.conf</filename>).
Include files are provided for four values: "none", "sysvinit",
"systemd", and "mdev-busybox".
The default value, "none", for <filename>INIT_MANAGER</filename>
should allow your current settings to continue working.
However, it is advisable to explicitly set
<filename>INIT_MANAGER</filename>.
</para>
</section>
<section id='migration-3.0-lsb-support-removed'>
<title>LSB Support Removed</title>
<para>
Linux Standard Base (LSB) as a standard is not current, and
is not well suited for embedded applications.
Support can be continued in a separate layer if needed.
However, presently LSB support has been removed from the core.
</para>
<para>
As a result of this change, the <filename>poky-lsb</filename>
derivative distribution configuration that was also used for
testing alternative configurations has been replaced with a
<filename>poky-altcfg</filename> distribution that has LSB
parts removed.
</para>
</section>
<section id='migration-3.0-removed-recipes'>
<title>Removed Recipes</title>
<para>
The following recipes have been removed.
<itemizedlist>
<listitem><para>
<filename>core-image-lsb-dev</filename>: Part of removed
LSB support.
</para></listitem>
<listitem><para>
<filename>core-image-lsb</filename>: Part of removed
LSB support.
</para></listitem>
<listitem><para>
<filename>core-image-lsb-sdk</filename>: Part of removed
LSB support.
</para></listitem>
<listitem><para>
<filename>cve-check-tool</filename>: Functionally replaced
by the <filename>cve-update-db</filename> recipe and
<filename>cve-check</filename> class.
</para></listitem>
<listitem><para>
<filename>eglinfo</filename>: No longer maintained.
<filename>eglinfo</filename> from
<filename>mesa-demos</filename> is an adequate and
maintained alternative.
</para></listitem>
<listitem><para>
<filename>gcc-8.3</filename>: Version 8.3 removed.
Replaced by 9.2.
</para></listitem>
<listitem><para>
<filename>gnome-themes-standard</filename>: Only needed
by gtk+ 2.x, which has been removed.
</para></listitem>
<listitem><para>
<filename>gtk+</filename>: GTK+ 2 is obsolete and has been
replaced by gtk+3.
</para></listitem>
<listitem><para>
<filename>irda-utils</filename>: Has become obsolete.
IrDA support has been removed from the Linux kernel in
version 4.17 and later.
</para></listitem>
<listitem><para>
<filename>libnewt-python</filename>:
<filename>libnewt</filename> Python support merged into
main <filename>libnewt</filename> recipe.
</para></listitem>
<listitem><para>
<filename>libsdl</filename>: Replaced by newer
<filename>libsdl2</filename>.
</para></listitem>
<listitem><para>
<filename>libx11-diet</filename>: Became obsolete.
</para></listitem>
<listitem><para>
<filename>libxx86dga</filename>: Removed obsolete client
library.
</para></listitem>
<listitem><para>
<filename>libxx86misc</filename>: Removed. Library is
redundant.
</para></listitem>
<listitem><para>
<filename>linux-yocto</filename>: Version 5.0 removed,
which is now redundant (5.2 / 4.19 present).
</para></listitem>
<listitem><para>
<filename>lsbinitscripts</filename>: Part of removed LSB
support.
</para></listitem>
<listitem><para>
<filename>lsb</filename>: Part of removed LSB support.
</para></listitem>
<listitem><para>
<filename>lsbtest</filename>: Part of removed LSB support.
</para></listitem>
<listitem><para>
<filename>openssl10</filename>: Replaced by newer
<filename>openssl</filename> version 1.1.
</para></listitem>
<listitem><para>
<filename>packagegroup-core-lsb</filename>: Part of removed
LSB support.
</para></listitem>
<listitem><para>
<filename>python-nose</filename>: Removed the Python 2.x
version of the recipe.
</para></listitem>
<listitem><para>
<filename>python-numpy</filename>: Removed the Python 2.x
version of the recipe.
</para></listitem>
<listitem><para>
<filename>python-scons</filename>: Removed the Python 2.x
version of the recipe.
</para></listitem>
<listitem><para>
<filename>source-highlight</filename>: No longer needed.
</para></listitem>
<listitem><para>
<filename>stress</filename>: Replaced by
<filename>stress-ng</filename>.
</para></listitem>
<listitem><para>
<filename>vulkan</filename>: Split into
<filename>vulkan-loader</filename>,
<filename>vulkan-headers</filename>, and
<filename>vulkan-tools</filename>.
</para></listitem>
<listitem><para>
<filename>weston-conf</filename>: Functionality moved to
<filename>weston-init</filename>.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.0-packaging-changes'>
<title>Packaging Changes</title>
<para>
The following packaging changes have occurred.
<itemizedlist>
<listitem><para>
The
<ulink url='https://en.wikipedia.org/wiki/GNOME_Web'>Epiphany</ulink>
browser has been dropped from
<filename>packagegroup-self-hosted</filename> as it has
not been needed inside
<filename>build-appliance-image</filename> for
quite some time and was causing resource problems.
</para></listitem>
<listitem><para>
<filename>libcap-ng</filename> Python support has been
moved to a separate <filename>libcap-ng-python</filename>
recipe to streamline the build process when the Python
bindings are not needed.
</para></listitem>
<listitem><para>
<filename>libdrm</filename> now packages the file
<filename>amdgpu.ids</filename> into a separate
<filename>libdrm-amdgpu</filename> package.
</para></listitem>
<listitem><para>
<filename>python3</filename>: The
<filename>runpy</filename> module is now in the
<filename>python3-core</filename> package as it is
required to support the common "python3 -m" command usage.
</para></listitem>
<listitem><para>
<filename>distcc</filename> now provides separate
<filename>distcc-client</filename> and
<filename>distcc-server</filename> packages as typically
one or the other are needed, rather than both.
</para></listitem>
<listitem><para>
<filename>python*-setuptools</filename> recipes now
separately package the <filename>pkg_resources</filename>
module in a <filename>python-pkg-resources</filename> /
<filename>python3-pkg-resources</filename> package as
the module is useful independent of the rest of the
setuptools package.
The main <filename>python-setuptools</filename> /
<filename>python3-setuptools</filename> package depends
on this new package so you should only need to update
dependencies unless you want to take advantage of the
increased granularity.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.0-cve-checking'>
<title>CVE Checking</title>
<para>
<filename>cve-check-tool</filename> has been functionally replaced
by a new <filename>cve-update-db</filename> recipe and
functionality built into the <filename>cve-check</filename> class.
The result uses NVD JSON data feeds rather than the deprecated
XML feeds that <filename>cve-check-tool</filename> was using,
supports CVSSv3 scoring, and makes other improvements.
</para>
<para>
Additionally, the <filename>CVE_CHECK_CVE_WHITELIST</filename>
variable has been replaced by
<filename>CVE_CHECK_WHITELIST</filename>.
</para>
</section>
<section id='migration-3.0-bitbake-changes'>
<title>Bitbake Changes</title>
<para>
The following BitBake changes have occurred.
<itemizedlist>
<listitem><para>
<filename>addtask</filename> statements now properly
validate dependent tasks.
Previously, an invalid task was silently ignored.
With this change, the invalid task generates a warning.
</para></listitem>
<listitem><para>
Other invalid <filename>addtask</filename> and
<filename>deltask</filename> usages now trigger these
warnings: "multiple target tasks arguments with
addtask / deltask", and "multiple before/after clauses".
</para></listitem>
<listitem><para>
The "multiconfig" prefix is now shortened to "mc".
"multiconfig" will continue to work, however it may be
removed in a future release.
</para></listitem>
<listitem><para>
The <filename>bitbake -g</filename> command no longer
generates a <filename>recipe-depends.dot</filename> file
as the contents (i.e. a reprocessed version of
<filename>task-depends.dot</filename>) were confusing.
</para></listitem>
<listitem><para>
The <filename>bb.build.FuncFailed</filename> exception,
previously raised by
<filename>bb.build.exec_func()</filename> when certain
other exceptions have occurred, has been removed.
The real underlying exceptions will be raised instead.
If you have calls to
<filename>bb.build.exec_func()</filename> in custom classes
or <filename>tinfoil-using</filename> scripts, any
references to <filename>bb.build.FuncFailed</filename>
should be cleaned up.
</para></listitem>
<listitem><para>
Additionally, the
<filename>bb.build.exec_func()</filename> no longer accepts
the "pythonexception" parameter.
The function now always raises exceptions.
Remove this argument in any calls to
<filename>bb.build.exec_func()</filename> in custom classes
or scripts.
</para></listitem>
<listitem><para>
The
<ulink url='&YOCTO_DOCS_BB_URL;#var-bb-BB_SETSCENE_VERIFY_FUNCTION2'><filename>BB_SETSCENE_VERIFY_FUNCTION2</filename></ulink>
is no longer used.
In the unlikely event that you have any references to it,
they should be removed.
</para></listitem>
<listitem><para>
The <filename>RunQueueExecuteScenequeue</filename> and
<filename>RunQueueExecuteTasks</filename> events have been
removed since setscene tasks are now executed as part of
the normal runqueue.
Any event handling code in custom classes or scripts that
handles these two events need to be updated.
</para></listitem>
<listitem><para>
The arguments passed to functions used with
<ulink url='&YOCTO_DOCS_BB_URL;#var-bb-BB_HASHCHECK_FUNCTION'><filename>BB_HASHCHECK_FUNCTION</filename></ulink>
have changed.
If you are using your own custom hash check function, see
<ulink url='http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=40a5e193c4ba45c928fccd899415ea56b5417725'></ulink>
for details.
</para></listitem>
<listitem><para>
Task specifications in <filename>BB_TASKDEPDATA</filename>
and class implementations used in signature generator
classes now use "&lt;fn&gt;:&lt;task&gt;" everywhere rather than
the "." delimiter that was being used in some places.
This change makes it consistent with all areas in the code.
Custom signature generator classes and code that reads
<filename>BB_TASKDEPDATA</filename> need to be updated to
use ':' as a separator rather than '.'.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.0-sanity-checks'>
<title>Sanity Checks</title>
<para>
The following sanity check changes occurred.
<itemizedlist>
<listitem><para>
<link linkend='var-SRC_URI'><filename>SRC_URI</filename></link>
is now checked for usage of two problematic items:
<itemizedlist>
<listitem><para>
"${PN}" prefix/suffix use - Warnings always appear
if ${PN} is used.
You must fix the issue regardless of whether
multiconfig or anything else that would cause
prefixing/suffixing to happen.
</para></listitem>
<listitem><para>
Github archive tarballs - these are not guaranteed
to be stable.
Consequently, it is likely that the tarballs will
be refreshed and thus the SRC_URI checksums
will fail to apply.
It is recommended that you fetch either an official
release tarball or a specific revision from the
actual Git repository instead.
</para></listitem>
</itemizedlist>
Either one of these items now trigger a warning by default.
If you wish to disable this check, remove
<filename>src-uri-bad</filename> from
<link linkend='var-WARN_QA'><filename>WARN_QA</filename></link>.
</para></listitem>
<listitem><para>
The <filename>file-rdeps</filename> runtime dependency
check no longer expands
<link linkend='var-RDEPENDS'><filename>RDEPENDS</filename></link>
recursively as there is no mechanism to ensure they can be
fully computed, and thus races sometimes result in errors
either showing up or not.
Thus, you might now see errors for missing runtime
dependencies that were previously satisfied recursively.
Here is an example: package A contains a shell script
starting with <filename>#!/bin/bash</filename> but has no
dependency on bash.
However, package A depends on package B, which does depend
on bash.
You need to add the missing dependency or dependencies to
resolve the warning.
</para></listitem>
<listitem><para>
Setting <filename>DEPENDS_${PN}</filename> anywhere
(i.e. typically in a recipe) now triggers an error.
The error is triggered because
<link linkend='var-DEPENDS'><filename>DEPENDS</filename></link>
is not a package-specific variable unlike RDEPENDS.
You should set <filename>DEPENDS</filename> instead.
</para></listitem>
<listitem><para>
systemd currently does not work well with the musl C
library because only upstream officially supports linking
the library with glibc.
Thus, a warning is shown when building systemd in
conjunction with musl.
</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.0-miscellaneous-changes'>
<title>Miscellaneous Changes</title>
<para>
The following miscellaneous changes have occurred.
<itemizedlist>
<listitem><para>
The <filename>gnome</filename>
class has been removed because it now does very little.
You should update recipes that previously inherited this
class to do the following:
<literallayout class='monospaced'>
inherit gnomebase gtk-icon-cache gconf mime
</literallayout>
</para></listitem>
<listitem><para>
The
<filename>meta/recipes-kernel/linux/linux-dtb.inc</filename>
file has been removed.
This file was previously deprecated in favor of setting
<link linkend='var-KERNEL_DEVICETREE'><filename>KERNEL_DEVICETREE</filename></link>
in any kernel recipe and only produced a warning.
Remove any <filename>include</filename> or
<filename>require</filename> statements pointing to this
file.
</para></listitem>
<listitem><para>
<link linkend='var-TARGET_CFLAGS'><filename>TARGET_CFLAGS</filename></link>,
<link linkend='var-TARGET_CPPFLAGS'><filename>TARGET_CPPFLAGS</filename></link>,
<link linkend='var-TARGET_CXXFLAGS'><filename>TARGET_CXXFLAGS</filename></link>,
and
<link linkend='var-TARGET_LDFLAGS'><filename>TARGET_LDFLAGS</filename></link>
are no longer exported to the external environment.
This change did not require any changes to core recipes,
which is a good indicator that no changes will be
required.
However, if for some reason the software being built by one
of your recipes is expecting these variables to be set,
then building the recipe will fail.
In such cases, you must either export the variable or
variables in the recipe or change the scripts so that
exporting is not necessary.
</para></listitem>
<listitem><para>
You must change the host distro identifier used in
<link linkend='var-NATIVELSBSTRING'><filename>NATIVELSBSTRING</filename></link>
to use all lowercase characters even if it does not contain
a version number.
This change is necessary only if you are not using
<filename>uninative</filename> and
<link linkend='var-SANITY_TESTED_DISTROS'><filename>SANITY_TESTED_DISTROS</filename></link>.
</para></listitem>
<listitem><para>
In the <filename>base-files</filename> recipe, writing the
hostname into <filename>/etc/hosts</filename> and
<filename>/etc/hostname</filename> is now done within the
main
<link linkend='ref-tasks-install'><filename>do_install</filename></link>
function rather than in the
<filename>do_install_basefilesissue</filename> function.
The reason for the change is because
<filename>do_install_basefilesissue</filename> is more
easily overridden without having to duplicate the hostname
functionality.
If you have done the latter (e.g. in a
<filename>base-files</filename> bbappend), then you should
remove it from your customized
<filename>do_install_basefilesissue</filename> function.
</para></listitem>
<listitem><para>
The <filename>wic --expand</filename> command now uses
commas to separate "key:value" pairs rather than hyphens.
<note>
The wic command-line help is not updated.
</note>
You must update any scripts or commands where you use
<filename>wic --expand</filename> with multiple
"key:value" pairs.
</para></listitem>
<listitem><para>
UEFI image variable settings have been moved from various
places to a central
<filename>conf/image-uefi.conf</filename>.
This change should not influence any existing configuration
as the <filename>meta/conf/image-uefi.conf</filename>
in the core metadata sets defaults that can be overridden
in the same manner as before.
</para></listitem>
<listitem><para>
<filename>conf/distro/include/world-broken.inc</filename>
has been removed.
For cases where certain recipes need to be disabled when
using the musl C library, these recipes now have
<filename>COMPATIBLE_HOST_libc-musl</filename> set with a
comment that explains why.
</para></listitem>
</itemizedlist>
</para>
</section>
</section>
<section id='moving-to-the-yocto-project-3.1-release'>
<title>Moving to the Yocto Project 3.1 Release</title>
<para>
This section provides migration information for moving to the
Yocto Project 3.1 Release from the prior release.
</para>
<section id='migration-3.1-minimum-system-requirements'>
<title>Minimum system requirements</title>
<para>
The following versions / requirements of build host components have been updated:
<itemizedlist>
<listitem><para>gcc 5.0</para></listitem>
<listitem><para>python 3.5</para></listitem>
<listitem><para>tar 1.28</para></listitem>
<listitem><para><filename>rpcgen</filename> is now required on the host (part of the <filename>libc-dev-bin</filename> package on Ubuntu, Debian and related distributions, and the <filename>glibc</filename> package on RPM-based distributions).</para></listitem>
</itemizedlist>
Additionally, the <filename>makeinfo</filename> and <filename>pod2man</filename>
tools are <emphasis>no longer</emphasis> required on the host.
</para>
</section>
<section id='migration-3.1-mpc8315e-rdb-removed'>
<title>mpc8315e-rdb machine removed</title>
<para>
The MPC8315E-RDB machine is old/obsolete and unobtainable, thus given the maintenance burden
the <filename>mpc8315e-rdb</filename> machine configuration that supported it has been removed
in this release. The removal does leave a gap in official PowerPC reference hardware
support; this may change in future if a suitable machine with accompanying support resources
is found.
</para>
</section>
<section id='migration-3.1-python-2-removed'>
<title>Python 2 removed</title>
<para>
Due to the expiration of upstream support in January 2020, support for Python 2 has now been removed; it is recommended that you use Python 3 instead. If absolutely needed there is a meta-python2 community layer containing Python 2, related classes and various Python 2-based modules, however it should not be considered as supported.
</para>
</section>
<section id='migration-3.1-reproducible-builds'>
<title>Reproducible builds now enabled by default</title>
<para>
In order to avoid unnecessary differences in output files (aiding binary reproducibility), the Poky distribution configuration (<filename><link linkend='var-DISTRO'>DISTRO</link> = "poky"</filename>) now inherits the <filename>reproducible_build</filename> class by default.
</para>
</section>
<section id='migration-3.1-ptest-feature-impact'>
<title>Impact of ptest feature is now more significant</title>
<para>
The Poky distribution configuration (<filename><link linkend='var-DISTRO'>DISTRO</link> = "poky"</filename>) enables ptests by default to enable runtime testing of various components. In this release, a dependency needed to be added that has resulted in a significant increase in the number of components that will be built just when building a simple image such as core-image-minimal. If you do not need runtime tests enabled for core components, then it is recommended that you remove "ptest" from <link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link> to save a significant amount of build time e.g. by adding the following in your configuration:
<literallayout class='monospaced'>
DISTRO_FEATURES_remove = "ptest"
</literallayout>
</para>
</section>
<section id='migration-3.1-removed-recipes'>
<title>Removed recipes</title>
<para>
The following recipes have been removed:
<itemizedlist>
<listitem><para><filename>chkconfig</filename>: obsolete</para></listitem>
<listitem><para><filename>console-tools</filename>: obsolete</para></listitem>
<listitem><para><filename>enchant</filename>: replaced by <filename>enchant2</filename></para></listitem>
<listitem><para><filename>foomatic-filters</filename>: obsolete</para></listitem>
<listitem><para><filename>libidn</filename>: no longer needed, moved to meta-oe</para></listitem>
<listitem><para><filename>libmodulemd</filename>: replaced by <filename>libmodulemd-v1</filename></para></listitem>
<listitem><para><filename>linux-yocto</filename>: drop 4.19, 5.2 version recipes (5.4 now provided)</para></listitem>
<listitem><para><filename>nspr</filename>: no longer needed, moved to meta-oe</para></listitem>
<listitem><para><filename>nss</filename>: no longer needed, moved to meta-oe</para></listitem>
<listitem><para><filename>python</filename>: Python 2 removed (Python 3 preferred)</para></listitem>
<listitem><para><filename>python-setuptools</filename>: Python 2 version removed (python3-setuptools preferred)</para></listitem>
<listitem><para><filename>sysprof</filename>: no longer needed, moved to meta-oe</para></listitem>
<listitem><para><filename>texi2html</filename>: obsolete</para></listitem>
<listitem><para><filename>u-boot-fw-utils</filename>: functionally replaced by <filename>libubootenv</filename></para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.1-features-check'>
<title>features_check class replaces distro_features_check</title>
<para>
The <filename>distro_features_check</filename> class has had its functionality expanded, now supporting <filename>ANY_OF_MACHINE_FEATURES</filename>, <filename>REQUIRED_MACHINE_FEATURES</filename>, <filename>CONFLICT_MACHINE_FEATURES</filename>, <filename>ANY_OF_COMBINED_FEATURES</filename>, <filename>REQUIRED_COMBINED_FEATURES</filename>, <filename>CONFLICT_COMBINED_FEATURES</filename>. As a result the class has now been renamed to <filename>features_check</filename>; the <filename>distro_features_check</filename> class still exists but generates a warning and redirects to the new class. In preparation for a future removal of the old class it is recommended that you update recipes currently inheriting <filename>distro_features_check</filename> to inherit <filename>features_check</filename> instead.
</para>
</section>
<section id='migration-3.1-removed-classes'>
<title>Removed classes</title>
<para>
The following classes have been removed:
<itemizedlist>
<listitem><para><filename>distutils-base</filename>: moved to meta-python2</para></listitem>
<listitem><para><filename>distutils</filename>: moved to meta-python2</para></listitem>
<listitem><para><filename>libc-common</filename>: merged into the glibc recipe as nothing else used it.</para></listitem>
<listitem><para><filename>python-dir</filename>: moved to meta-python2</para></listitem>
<listitem><para><filename>pythonnative</filename>: moved to meta-python2</para></listitem>
<listitem><para><filename>setuptools</filename>: moved to meta-python2</para></listitem>
<listitem><para><filename>tinderclient</filename>: dropped as it was obsolete.</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.1-src-uri-checksums'>
<title>SRC_URI checksum behaviour</title>
<para>
Previously, recipes by tradition included both SHA256 and MD5 checksums for remotely fetched files in <link linkend='var-SRC_URI'><filename>SRC_URI</filename></link>, even though only one is actually mandated. However, the MD5 checksum does not add much given its inherent weakness; thus when a checksum fails only the SHA256 sum will now be printed. The md5sum will still be verified if it is specified.
</para>
</section>
<section id='migration-3.1-npm'>
<title>npm fetcher changes</title>
<para>
The npm fetcher has been completely reworked in this release. The npm fetcher now only fetches the package source itself and no longer the dependencies; there is now also an npmsw fetcher which explicitly fetches the shrinkwrap file and the dependencies. This removes the slightly awkward <filename>NPM_LOCKDOWN</filename> and <filename>NPM_SHRINKWRAP</filename> variables which pointed to local files; the lockdown file is no longer needed at all. Additionally, the package name in <filename>npm://</filename> entries in <link linkend='var-SRC_URI'><filename>SRC_URI</filename></link> is now specified using a <filename>package</filename> parameter instead of the earlier <filename>name</filename> which overlapped with the generic <filename>name</filename> parameter. All recipes using the npm fetcher will need to be changed as a result.
</para>
<para>
An example of the new scheme:
<literallayout class='monospaced'>
SRC_URI = "npm://registry.npmjs.org;package=array-flatten;version=1.1.1 \
npmsw://${THISDIR}/npm-shrinkwrap.json"
</literallayout>
Another example where the sources are fetched from git rather than an npm repository:
<literallayout class='monospaced'>
SRC_URI = "git://github.com/foo/bar.git;protocol=https \
npmsw://${THISDIR}/npm-shrinkwrap.json"
</literallayout>
</para>
<para>
devtool and recipetool have also been updated to match with the npm fetcher changes. Other than producing working and more complete recipes for npm sources, there is also a minor change to the command line for devtool: the <filename>--fetch-dev</filename> option has been renamed to <filename>--npm-dev</filename> as it is npm-specific.
</para>
</section>
<section id='migration-3.1-packaging-changes'>
<title>Packaging changes</title>
<para>
<itemizedlist>
<listitem><para><filename>intltool</filename> has been removed from <filename>packagegroup-core-sdk</filename> as it is rarely needed to build modern software - gettext can do most of the things it used to be needed for. <filename>intltool</filename> has also been removed from <filename>packagegroup-core-self-hosted</filename> as it is not needed to for standard builds.</para></listitem>
<listitem><para>git: <filename>git-am</filename>, <filename>git-difftool</filename>, <filename>git-submodule</filename>, and <filename>git-request-pull</filename> are no longer perl-based, so are now installed with the main <filename>git</filename> package instead of within <filename>git-perltools</filename>.</para></listitem>
<listitem><para>The <filename>ldconfig</filename> binary built as part of glibc has now been moved to its own <filename>ldconfig</filename> package (note no <filename>glibc-</filename> prefix). This package is in the <link linkend='var-RRECOMMENDS'><filename>RRECOMMENDS</filename></link> of the main <filename>glibc</filename> package if <filename>ldconfig</filename> is present in <link linkend='var-DISTRO_FEATURES'><filename>DISTRO_FEATURES</filename></link>.</para></listitem>
<listitem><para><filename>libevent</filename> now splits each shared library into its own package (as Debian does). Since these are shared libraries and will be pulled in through the normal shared library dependency handling, there should be no impact to existing configurations other than less unnecessary libraries being installed in some cases.</para></listitem>
<listitem><para>linux-firmware now has a new package for <filename>bcm4366c</filename> and includes available NVRAM config files into the <filename>bcm43340</filename>, <filename>bcm43362</filename>, <filename>bcm43430</filename> and <filename>bcm4356-pcie</filename> packages.</para></listitem>
<listitem><para><filename>harfbuzz</filename> now splits the new <filename>libharfbuzz-subset.so</filename> library into its own package to reduce the main package size in cases where <filename>libharfbuzz-subset.so</filename> is not needed.</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.1-package-qa-warnings'>
<title>Additional warnings</title>
<para>
Warnings will now be shown at <filename>do_package_qa</filename> time in the following circumstances:
<itemizedlist>
<listitem><para>A recipe installs <filename>.desktop</filename> files containing <filename>MimeType</filename> keys but does not inherit the new <filename>mime-xdg</filename> class</para></listitem>
<listitem><para>A recipe installs <filename>.xml</filename> files into <filename>${datadir}/mime/packages</filename> but does not inherit the <filename>mime</filename> class</para></listitem>
</itemizedlist>
</para>
</section>
<section id='migration-3.1-x86-live-wic'>
<title><filename>wic</filename> image type now used instead of <filename>live</filename> by default for x86</title>
<para>
<filename>conf/machine/include/x86-base.inc</filename> (inherited by most x86 machine configurations) now specifies <filename>wic</filename> instead of <filename>live</filename> by default in <link linkend='var-IMAGE_FSTYPES'><filename>IMAGE_FSTYPES</filename></link>. The <filename>live</filename> image type will likely be removed in a future release so it is recommended that you use <filename>wic</filename> instead.
</para>
</section>
<section id='migration-3.1-misc'>
<title>Miscellaneous changes</title>
<para>
<itemizedlist>
<listitem><para>The undocumented <filename>SRC_DISTRIBUTE_LICENSES</filename> variable has now been removed in favour of a new <filename>AVAILABLE_LICENSES</filename> variable which is dynamically set based upon license files found in <filename>${COMMON_LICENSE_DIR}</filename> and <filename>${LICENSE_PATH}</filename>.</para></listitem>
<listitem><para>The tune definition for big-endian microblaze machines is now <filename>microblaze</filename> instead of <filename>microblazeeb</filename>.</para></listitem>
<listitem><para><filename>newlib</filename> no longer has built-in syscalls. <filename>libgloss</filename> should then provide the syscalls, <filename>crt0.o</filename> and other functions that are no longer part of <filename>newlib</filename> itself. If you are using <filename>TCLIBC = "newlib"</filename> this now means that you must link applications with both <filename>newlib</filename> and <filename>libgloss</filename>, whereas before <filename>newlib</filename> would run in many configurations by itself.</para></listitem>
</itemizedlist>
</para>
</section>
</section>
</chapter>
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