%poky; ] > 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.

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. Dealing with Customized Recipes: 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. 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. The better solution (where practical) is to use append files (*.bbappend) 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. Updating Append Files: Since append files generally only contain your customizations, they often do not need to be adjusted for new releases. However, if the .bbappend 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 (.bb) will trigger an error during parsing. 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.

This section provides migration information for moving to the Yocto Project 1.3 Release from the prior release.

Differences include changes for SSTATE_MIRRORS and bblayers.conf.

The shared state cache (sstate-cache), as pointed to by SSTATE_DIR, 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 SSTATE_MIRRORS, 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: SSTATE_MIRRORS = "file://.* http://someserver.tld/share/sstate/PATH"

The meta-yocto layer consists of two parts that correspond to the Poky reference distribution and the reference hardware Board Support Packages (BSPs), respectively: meta-yocto and meta-yocto-bsp. When running BitBake for the first time after upgrading, your conf/bblayers.conf file will be updated to handle this change and you will be asked to re-run or restart for the changes to take effect.

Differences include changes for the following: Python function whitespace proto= in SRC_URI nativesdk Task recipes IMAGE_FEATURES Removed recipes

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 _append or _prepend complicated given that Python treats whitespace as syntactically significant. If you are defining or extending any Python functions (e.g. populate_packages, do_unpack, do_patch and so forth) in custom recipes or classes, you need to ensure you are using consistent four-space indentation.

Any use of proto= in SRC_URI needs to be changed to protocol=. In particular, this applies to the following URIs: svn:// bzr:// hg:// osc:// Other URIs were already using protocol=. This change improves consistency.

The suffix nativesdk is now implemented as a prefix, which simplifies a lot of the packaging code for nativesdk recipes. All custom nativesdk recipes, which are relocatable packages that are native to SDK_ARCH, and any references need to be updated to use nativesdk-* instead of *-nativesdk.

"Task" recipes are now known as "Package groups" and have been renamed from task-*.bb to packagegroup-*.bb. Existing references to the previous task-* 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 task-* recipes to packagegroup-*, and change them to inherit packagegroup instead of task, as well as taking the opportunity to remove anything now handled by packagegroup.bbclass, such as providing -dev and -dbg packages, setting LIC_FILES_CHKSUM, and so forth. See the "packagegroup.bbclass" section for further details.

Image recipes that previously included "apps-console-core" in IMAGE_FEATURES 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" IMAGE_FEATURES features have been removed.

The following recipes have been removed. For most of them, it is unlikely that you would have any references to them in your own Metadata. However, you should check your metadata against this list to be sure: libx11-trim: Replaced by libx11, which has a negligible size difference with modern Xorg. xserver-xorg-lite: Use xserver-xorg, which has a negligible size difference when DRI and GLX modules are not installed. xserver-kdrive: Effectively unmaintained for many years. mesa-xlib: No longer serves any purpose. galago: Replaced by telepathy. gail: Functionality was integrated into GTK+ 2.13. eggdbus: No longer needed. gcc-*-intermediate: The build has been restructured to avoid the need for this step. libgsmd: Unmaintained for many years. Functionality now provided by ofono instead. contacts, dates, tasks, eds-tools: Largely unmaintained PIM application suite. It has been moved to meta-gnome in meta-openembedded. In addition to the previously listed changes, the meta-demoapps 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 meta-oe and meta-gnome. For the remainder, you can now find them in the meta-extras repository, which is in the Yocto Project Source Repositories.

The naming scheme for kernel output binaries has been changed to now include PE as part of the filename: KERNEL_IMAGE_BASE_NAME ?= "${KERNEL_IMAGETYPE}-${PE}-${PV}-${PR}-${MACHINE}-${DATETIME}" Because the PE variable is not set by default, these binary files could result with names that include two dash characters. Here is an example: bzImage--3.10.9+git0+cd502a8814_7144bcc4b8-r0-qemux86-64-20130830085431.bin

This section provides migration information for moving to the Yocto Project 1.4 Release from the prior release.

Differences include the following: Comment Continuation: 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. Package Name Overrides: The runtime package specific variables RDEPENDS, RRECOMMENDS, RSUGGESTS, RPROVIDES, RCONFLICTS, RREPLACES, FILES, ALLOW_EMPTY, and the pre, post, install, and uninstall script functions pkg_preinst, pkg_postinst, pkg_prerm, and pkg_postrm should always have a package name override. For example, use RDEPENDS_${PN} for the main package instead of RDEPENDS. BitBake uses more strict checks when it parses recipes.

Differences include the following: Shared State Code: 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: $ bitbake -c rootfs some-image 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. Scanning Directory Names: When scanning for files in SRC_URI, the build system now uses FILESOVERRIDES instead of OVERRIDES for the directory names. In general, the values previously in OVERRIDES are now in FILESOVERRIDES as well. However, if you relied upon an additional value you previously added to OVERRIDES, you might now need to add it to FILESOVERRIDES unless you are already adding it through the MACHINEOVERRIDES or DISTROOVERRIDES variables, as appropriate. For more related changes, see the "Variables" section.

A new oe-git-proxy script has been added to replace previous methods of handling proxies and fetching source from Git. See the meta-yocto/conf/site.conf.sample file for information on how to use this script.

If you have created your own custom etc/network/interfaces file by creating an append file for the netbase recipe, you now need to create an append file for the init-ifupdown recipe instead, which you can find in the Source Directory at meta/recipes-core/init-ifupdown. For information on how to use append files, see the "Using .bbappend Files" in the Yocto Project Development Manual.

Support for remote debugging with the Eclipse IDE is now separated into an image feature (eclipse-debug) that corresponds to the packagegroup-core-eclipse-debug package group. Previously, the debugging feature was included through the tools-debug image feature, which corresponds to the packagegroup-core-tools-debug package group.

The following variables have changed: SANITY_TESTED_DISTROS: This variable now uses a distribution ID, which is composed of the host distributor ID followed by the release. Previously, SANITY_TESTED_DISTROS 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 "". SRC_URI: The ${PN}, ${PF}, ${P}, and FILE_DIRNAME directories have been dropped from the default value of the FILESPATH variable, which is used as the search path for finding files referred to in SRC_URI. 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 ${BP}, ${BPN}, and "files", which all remain in the default value of FILESPATH.

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: smart --help

The following recipes were moved from their previous locations because they are no longer used by anything in the OpenEmbedded-Core: clutter-box2d: Now resides in the meta-oe layer. evolution-data-server: Now resides in the meta-gnome layer. gthumb: Now resides in the meta-gnome layer. gtkhtml2: Now resides in the meta-oe layer. gupnp: Now resides in the meta-multimedia layer. gypsy: Now resides in the meta-oe layer. libcanberra: Now resides in the meta-gnome layer. libgdata: Now resides in the meta-gnome layer. libmusicbrainz: Now resides in the meta-multimedia layer. metacity: Now resides in the meta-gnome layer. polkit: Now resides in the meta-oe layer. zeroconf: Now resides in the meta-networking layer.

The following list shows what has been removed or renamed: evieext: Removed because it has been removed from xserver since 2008. Gtk+ DirectFB: Removed support because upstream Gtk+ no longer supports it as of version 2.18. libxfontcache / xfontcacheproto: Removed because they were removed from the Xorg server in 2008. libxp / libxprintapputil / libxprintutil / printproto: Removed because the XPrint server was removed from Xorg in 2008. libxtrap / xtrapproto: Removed because their functionality was broken upstream. linux-yocto 3.0 kernel: 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. lsbsetup: Removed with functionality now provided by lsbtest. matchbox-stroke: Removed because it was never more than a proof-of-concept. matchbox-wm-2 / matchbox-theme-sato-2: Removed because they are not maintained. However, matchbox-wm and matchbox-theme-sato are still provided. mesa-dri: Renamed to mesa. mesa-xlib: Removed because it was no longer useful. mutter: Removed because nothing ever uses it and the recipe is very old. orinoco-conf: Removed because it has become obsolete. update-modules: Removed because it is no longer used. The kernel module postinstall and postrm scripts can now do the same task without the use of this script. web: Removed because it is not maintained. Superseded by web-webkit. xf86bigfontproto: Removed because upstream it has been disabled by default since 2007. Nothing uses xf86bigfontproto. xf86rushproto: Removed because its dependency in xserver was spurious and it was removed in 2005. zypper / libzypp / sat-solver: Removed and been functionally replaced with Smart (python-smartpm) when RPM packaging is used and package management is enabled on the target.

This section provides migration information for moving to the Yocto Project 1.5 Release from the prior release.

The OpenEmbedded build system now has some additional requirements on the host system: Python 2.7.3+ Tar 1.24+ Git 1.7.8+ Patched version of Make if you are using 3.82. Most distributions that provide Make 3.82 use the patched version. 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. For more information on this requirement, see the "Required Git, tar, and Python Versions" section.

The atom-pc hardware reference BSP has been replaced by a genericx86 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 atom-pc did. Additionally, a genericx86-64 BSP has been added for 64-bit Atom systems.

The following changes have been made that relate to BitBake: BitBake now supports a _remove operator. The addition of this operator means you will have to rename any items in recipe space (functions, variables) whose names currently contain _remove_ or end with _remove to avoid unexpected behavior. 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. The "none" server backend has been removed. The "process" server backend has been serving well as the default for a long time now. The bitbake-runtask script has been removed. ${P} and ${PF} are no longer added to PROVIDES by default in bitbake.conf. These version-specific PROVIDES 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.

The following changes have been made to the package QA checks: If you have customized ERROR_QA or WARN_QA 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 ERROR_QA or WARN_QA would be treated as a warning. Consequently, several important items were not already in the default value of WARN_QA. All of the possible QA checks are now documented in the "insane.bbclass" section. An additional QA check has been added to check if /usr/share/info/dir is being installed. Your recipe should delete this file within do_install if "make install" is installing it. 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 ERROR_QA or WARN_QA 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 "insane.bbclass" section.

The following directory changes exist: Output SDK installer files are now named to include the image name and tuning architecture through the SDK_NAME variable. 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 DEPLOY_DIR_IMAGE variable continues to point to the directory containing images for the current MACHINE and should be used anywhere there is a need to refer to this directory. The runqemu script now uses this variable to find images and kernel binaries and will use BitBake to determine the directory. Alternatively, you can set the DEPLOY_DIR_IMAGE variable in the external environment. When buildhistory is enabled, its output is now written under the Build Directory rather than TMPDIR. Doing so makes it easier to delete TMPDIR and preserve the build history. Additionally, data for produced SDKs is now split by IMAGE_NAME. The pkgdata directory produced as part of the packaging process has been collapsed into a single machine-specific directory. This directory is located under sysroots and uses a machine-specific name (i.e. tmp/sysroots/machine/pkgdata).

BitBake will now shorten revisions from Git repositories from the normal 40 characters down to 10 characters within SRCPV 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.

The following changes have been made that relate to IMAGE_FEATURES: The value of IMAGE_FEATURES is now validated to ensure invalid feature items are not added. Some users mistakenly add package names to this variable instead of using IMAGE_INSTALL 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 IMAGE_FEATURES are drawn from PACKAGE_GROUP definitions, COMPLEMENTARY_GLOB and a new "validitems" varflag on IMAGE_FEATURES. The "validitems" varflag change allows additional features to be added if they are not provided using the previous two mechanisms. The previously deprecated "apps-console-core" IMAGE_FEATURES item is no longer supported. Add "splash" to IMAGE_FEATURES if you wish to have the splash screen enabled, since this is all that apps-console-core was doing.

The /run directory from the Filesystem Hierarchy Standard 3.0 has been introduced. You can find some of the implications for this change here. The change also means that recipes that install files to /var/run must be changed. You can find a guide on how to make these changes here.

The image core-image-minimal no longer adds remove_packaging_data_files to ROOTFS_POSTPROCESS_COMMAND. This addition is now handled automatically when "package-management" is not in IMAGE_FEATURES. 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.

The do_rootfs 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.

The previously deprecated task.bbclass has now been dropped. For recipes that previously inherited from this class, you should rename them from task-* to packagegroup-* and inherit packagegroup instead. For more information, see the "packagegroup.bbclass" section.

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 tinylogin recipe as recommended by upstream. You can disable this split by setting BUSYBOX_SPLIT_SUID to "0".

A new automated image testing framework has been added through the testimage.bbclass class. This framework replaces the older imagetest-qemu framework. You can learn more about performing automated image tests in the "Performing Automated Runtime Testing" section.

Following are changes to Build History: Installed package sizes: installed-package-sizes.txt for an image now records the size of the files installed by each package instead of the size of each compressed package archive file. The dependency graphs (depends*.dot) now use the actual package names instead of replacing dashes, dots and plus signs with underscores. The buildhistory-diff and buildhistory-collect-srcrevs utilities have improved command-line handling. Use the --help option for each utility for more information on the new syntax. For more information on Build History, see the "Maintaining Build Output Quality" section.

Following are changes to udev: udev no longer brings in udev-extraconf automatically through RRECOMMENDS, since this was originally intended to be optional. If you need the extra rules, then add udev-extraconf to your image. udev no longer brings in pciutils-ids or usbutils-ids through RRECOMMENDS. These are not needed by udev itself and removing them saves around 350KB.

The linux-yocto 3.2 kernel has been removed. libtool-nativesdk has been renamed to nativesdk-libtool. tinylogin has been removed. It has been replaced by a suid portion of Busybox. See the "BusyBox" section for more information. external-python-tarball has been renamed to buildtools-tarball. web-webkit has been removed. It has been functionally replaced by midori. imake has been removed. It is no longer needed by any other recipe. transfig-native has been removed. It is no longer needed by any other recipe. anjuta-remote-run has been removed. Anjuta IDE integration has not been officially supported for several releases.

Following is a list of short entries describing other changes: run-postinsts: Make this generic. base-files: Remove the unnecessary media/xxx directories. alsa-state: Provide an empty asound.conf by default. classes/image: Ensure BAD_RECOMMENDATIONS supports pre-renamed package names. classes/rootfs_rpm: Implement BAD_RECOMMENDATIONS for RPM. systemd: Remove systemd_unitdir if systemd is not in DISTRO_FEATURES. systemd: Remove init.d dir if systemd unit file is present and sysvinit is not a distro feature. libpam: Deny all services for the OTHER entries. image.bbclass: Move runtime_mapping_rename to avoid conflict with multilib. See YOCTO #4993 in Bugzilla for more information. linux-dtb: Use kernel build system to generate the dtb files. kern-tools: Switch from guilt to new kgit-s2q tool.

This section provides migration information for moving to the Yocto Project 1.6 Release from the prior release.

The archiver class has been rewritten and its configuration has been simplified. For more details on the source archiver, see the "Maintaining Open Source License Compliance During Your Product's Lifecycle" section in the Yocto Project Development Manual.

The following packaging changes have been made: The binutils recipe no longer produces a binutils-symlinks package. update-alternatives is now used to handle the preferred binutils variant on the target instead. The tc (traffic control) utilities have been split out of the main iproute2 package and put into the iproute2-tc package. The gtk-engines schemas have been moved to a dedicated gtk-engines-schemas package. The armv7a 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.

The following changes have been made to BitBake.

When fetching source from a Git repository using SRC_URI, BitBake will now validate the SRCREV value against the branch. You can specify the branch using the following form: SRC_URI = "git://server.name/repository;branch=branchname" If you do not specify a branch, BitBake looks in the default "master" branch. 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 SRC_URI.

BitBake had some previously deprecated Python definitions within its bb module removed. You should use their sub-module counterparts instead: bb.MalformedUrl: Use bb.fetch.MalformedUrl. bb.encodeurl: Use bb.fetch.encodeurl. bb.decodeurl: Use bb.fetch.decodeurl bb.mkdirhier: Use bb.utils.mkdirhier. bb.movefile: Use bb.utils.movefile. bb.copyfile: Use bb.utils.copyfile. bb.which: Use bb.utils.which. bb.vercmp_string: Use bb.utils.vercmp_string. bb.vercmp: Use bb.utils.vercmp.

The SVK fetcher has been removed from BitBake.

The BitBake console UI will now output errors to stderr instead of stdout. Consequently, if you are piping or redirecting the output of bitbake to somewhere else, and you wish to retain the errors, you will need to add 2>&1 (or something similar) to the end of your bitbake command line.

task-taskname 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 do_populate_sdk is task-populate-sdk.

The following variables have changed. For information on the OpenEmbedded build system variables, see the "Variables Glossary" Chapter.

TMPDIR 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 TMPDIR. The check for this occurs on startup. If TMPDIR is detected on an NFS mount, an error occurs.

The PRINC variable has been deprecated and triggers a warning if detected during a build. For PR increments on changes, use the PR service instead. You can find out more about this service in the "Working With a PR Service" section in the Yocto Project Development Manual.

The "sum.jffs2" option for IMAGE_TYPES has been replaced by the "jffs2.sum" option, which fits the processing order.

The COPY_LIC_MANIFEST variable must now be set to "1" rather than any value in order to enable it.

The COPY_LIC_DIRS variable must now be set to "1" rather than any value in order to enable it.

The PACKAGE_GROUP variable has been renamed to FEATURE_PACKAGES to more accurately reflect its purpose. You can still use PACKAGE_GROUP but the OpenEmbedded build system produces a warning message when it encounters the variable.

The following variables now expect a semicolon separated list of functions to call and not arbitrary shell commands: ROOTFS_PREPROCESS_COMMAND ROOTFS_POSTPROCESS_COMMAND SDK_POSTPROCESS_COMMAND POPULATE_SDK_POST_TARGET_COMMAND POPULATE_SDK_POST_HOST_COMMAND IMAGE_POSTPROCESS_COMMAND IMAGE_PREPROCESS_COMMAND ROOTFS_POSTUNINSTALL_COMMAND ROOTFS_POSTINSTALL_COMMAND For migration purposes, you can simply wrap shell commands in a shell function and then call the function. Here is an example: my_postprocess_function() { echo "hello" > ${IMAGE_ROOTFS}/hello.txt } ROOTFS_POSTPROCESS_COMMAND += "my_postprocess_function; "

Package Tests (ptest) are built but not installed by default. For information on using Package Tests, see the "Setting up and running package test (ptest)" section in the Yocto Project Development Manual. For information on the ptest class, see the "ptest.bbclass" section.

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 cmake class. In future releases the autotools 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 autotools-brokensep class instead of the autotools or autotools_stageclasses.

qemu-native now builds without SDL-based graphical output support by default. The following additional lines are needed in your local.conf to enable it: PACKAGECONFIG_pn-qemu-native = "sdl" ASSUME_PROVIDED += "libsdl-native" The default local.conf contains these statements. Consequently, if you are building a headless system and using a default local.conf file, you will need comment these two lines out.

core-image-basic has been renamed to core-image-full-cmdline. In addition to core-image-basic being renamed, packagegroup-core-basic has been renamed to packagegroup-core-full-cmdline to match.

The top-level LICENSE file has been changed to better describe the license of the various components of OE-Core. However, the licensing itself remains unchanged. Normally, this change would not cause any side-effects. However, some recipes point to this file within LIC_FILES_CHKSUM (as ${COREBASE}/LICENSE) and thus the accompanying checksum must be changed from 3f40d7994397109285ec7b81fdeb3b58 to 4d92cd373abda3937c2bc47fbc49d690. A better alternative is to have LIC_FILES_CHKSUM point to a file describing the license that is distributed with the source that the recipe is building, if possible, rather than pointing to ${COREBASE}/LICENSE.

The "-fpermissive" option has been removed from the default CFLAGS 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 CFLAGS in the recipes.

Custom image output types, as selected using IMAGE_FSTYPES, must declare their dependencies on other image types (if any) using a new IMAGE_TYPEDEP variable.

The do_package_write task has been removed. The task is no longer needed.

The default update-alternatives provider has been changed from opkg to opkg-utils. This change resolves some troublesome circular dependencies. The runtime package has also been renamed from update-alternatives-cworth to update-alternatives-opkg.

The virtclass overrides are now deprecated. Use the equivalent class overrides instead (e.g. virtclass-native becomes class-native.)

The following recipes have been removed: packagegroup-toolset-native - This recipe is largely unused. linux-yocto-3.8 - 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 linux-yocto-3.10 and linux-yocto-3.14 recipes. ocf-linux - This recipe has been functionally replaced using cryptodev-linux. genext2fs - genext2fs is no longer used by the build system and is unmaintained upstream. js - This provided an ancient version of Mozilla's javascript engine that is no longer needed. zaurusd - The recipe has been moved to the meta-handheld layer. eglibc 2.17 - Replaced by the eglibc 2.19 recipe. gcc 4.7.2 - Replaced by the now stable gcc 4.8.2. external-sourcery-toolchain - this recipe is now maintained in the meta-sourcery layer. linux-libc-headers-yocto 3.4+git - Now using version 3.10 of the linux-libc-headers by default. meta-toolchain-gmae - This recipe is obsolete. packagegroup-core-sdk-gmae - This recipe is obsolete. packagegroup-core-standalone-gmae-sdk-target - This recipe is obsolete.

The following classes have become obsolete and have been removed: module_strip pkg_metainfo pkg_distribute image-empty

The following reference BSPs changes occurred: The BeagleBoard (beagleboard) ARM reference hardware has been replaced by the BeagleBone (beaglebone) hardware. The RouterStation Pro (routerstationpro) MIPS reference hardware has been replaced by the EdgeRouter Lite (edgerouter) hardware. The previous reference BSPs for the beagleboard and routerstationpro machines are still available in a new meta-yocto-bsp-old layer in the Source Repositories at http://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto-bsp-old/.

This section provides migration information for moving to the Yocto Project 1.7 Release from the prior release.

The QEMU recipe now uses a number of PACKAGECONFIG options to enable various optional features. The method used to set defaults for these options means that existing local.conf files will need to be be modified to append to PACKAGECONFIG for qemu-native and nativesdk-qemu instead of setting it. In other words, to enable graphical output for QEMU, you should now have these lines in local.conf: PACKAGECONFIG_append_pn-qemu-native = " sdl" PACKAGECONFIG_append_pn-nativesdk-qemu = " sdl"

The minimum Git version required on the build host is now 1.7.8 because the --list 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 buildtools-tarball that does. See the "Required Git, tar, and Python Versions" section for more information.

The following autotools class changes occurred: A separate build directory is now used by default: The autotools class has been changed to use a directory for building (B), which is separate from the source directory (S). This is commonly referred to as B != S, or an out-of-tree build. 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 autotools-brokensep class instead of the autotools or autotools_stage classes. The --foreign option is no longer passed to automake when running autoconf: This option tells automake that a particular software package does not follow the GNU standards and therefore should not be expected to distribute certain files such as ChangeLog, AUTHORS, and so forth. Because the majority of upstream software packages already tell automake 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 configure.ac so that it passes "foreign" to AM_INIT_AUTOMAKE(). See this commit for an example showing how to make the patch.

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 pkg-config instead. The list of recipes changed in this version (and their configuration scripts) is as follows: 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) Additionally, support for pkg-config has been added to some recipes in the previous list in the rare cases where the upstream software package does not already provide it.

Because eglibc and glibc were already fairly close, this replacement should not require any significant changes to other software that links to eglibc. However, there were a number of minor changes in glibc 2.20 upstream that could require patching some software (e.g. the removal of the _BSD_SOURCE feature test macro). glibc 2.20 requires version 2.6.32 or greater of the Linux kernel. Thus, older kernels will no longer be usable in conjunction with it. For full details on the changes in glibc 2.20, see the upstream release notes here.

The module_autoload_* variable is now deprecated and a new KERNEL_MODULE_AUTOLOAD variable should be used instead. Also, module_conf_* must now be used in conjunction with a new KERNEL_MODULE_PROBECONF 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 module_autoload_* with KERNEL_MODULE_AUTOLOAD, and add any modules for which module_conf_* is specified to KERNEL_MODULE_PROBECONF. For more information, see the KERNEL_MODULE_AUTOLOAD and KERNEL_MODULE_PROBECONF variables.

The following changes have occurred to the QA check process: Additional QA checks file-rdeps and build-deps have been added in order to verify that file dependencies are satisfied (e.g. package contains a script requiring /bin/bash) and build-time dependencies are declared, respectively. For more information, please see the "QA Error and Warning Messages" chapter. Package QA checks are now performed during a new do_package_qa task rather than being part of the do_package 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 noexec. For those packages, you will need to disable the do_package_qa task as well. Files being overwritten during the do_populate_sysroot 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. 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 TMPDIR 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.

The following recipes have been removed: x-load: This recipe has been superseded by U-boot SPL for all Cortex-based TI SoCs. For legacy boards, the meta-ti layer, which contains a maintained recipe, should be used instead. ubootchart: This recipe is obsolete. A bootchart2 recipe has been added to functionally replace it. linux-yocto 3.4: 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. eglibc has been removed in favor of glibc. See the "eglibc 2.19 Replaced with glibc 2.20" section for more information.

The following miscellaneous change occurred: The build history feature now writes build-id.txt instead of build-id. Additionally, build-id.txt 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 "Maintaining Build Output Quality" section.

This section provides migration information for moving to the Yocto Project 1.8 Release from the prior release.

The following recipes have been removed: owl-video: Functionality replaced by gst-player. gaku: Functionality replaced by gst-player. gnome-desktop: This recipe is now available in meta-gnome and is no longer needed. gsettings-desktop-schemas: This recipe is now available in meta-gnome and is no longer needed. python-argparse: The argparse module is already provided in the default Python distribution in a package named python-argparse. Consequently, the separate python-argparse recipe is no longer needed. telepathy-python, libtelepathy, telepathy-glib, telepathy-idle, telepathy-mission-control: All these recipes have moved to meta-oe and are consequently no longer needed by any recipes in OpenEmbedded-Core. linux-yocto_3.10 and linux-yocto_3.17: 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. poky-feed-config-opkg: This recipe has become obsolete and is no longer needed. Use distro-feed-config from meta-oe instead. libav 0.8.x: libav 9.x is now used. sed-native: No longer needed. A working version of sed is expected to be provided by the host distribution.

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 DISTRO_FEATURES value. If you had previously added append files (*.bbappend) to make this selection, you can now remove them. Additionally, a bluetooth 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: 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"

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 ${S} (source files) and ${B} (build artifacts) are used correctly in functions such as do_configure and do_install. For kernel recipes that do not inherit from kernel-yocto or include linux-yocto.inc, you might wish to refer to the linux.inc file in the meta-oe layer for the kinds of changes you need to make. For reference, here is the commit where the linux.inc file in meta-oe was updated. Recipes that rely on the kernel source code and do not inherit the module classes might need to add explicit dependencies on the do_shared_workdir kernel task, for example: do_configure[depends] += "virtual/kernel:do_shared_workdir"

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 (*.bbappend) for the openssl recipe to remove "-no-ssl3" from EXTRA_OECONF.

gcc's 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. 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.

Changes have been made to the base, autotools, and cmake classes to clean out generated files when the do_configure task needs to be re-executed. One of the improvements is to attempt to run "make clean" during the do_configure task if a Makefile exists. Some software packages do not provide a working clean target within their make files. If you have such recipes, you need to set CLEANBROKEN to "1" within the recipe, for example: CLEANBROKEN = "1"

The following QA Check and Validation Changes have occurred: Usage of PRINC previously triggered a warning. It now triggers an error. You should remove any remaining usage of PRINC in any recipe or append file. An additional QA check has been added to detect usage of ${D} in FILES values where D values should not be used at all. The same check ensures that $D is used in pkg_preinst/pkg_postinst/pkg_prerm/pkg_postrm functions instead of ${D}. S now needs to be set to a valid value within a recipe. If S is not set in the recipe, the directory is not automatically created. If S does not point to a directory that exists at the time the do_unpack task finishes, a warning will be shown. LICENSE 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.

The following miscellaneous changes have occurred: The send-error-report script now expects a "-s" option to be specified before the server address. This assumes a server address is being specified. The oe-pkgdata-util script now expects a "-p" option to be specified before the pkgdata directory, which is now optional. If the pkgdata directory is not specified, the script will run BitBake to query PKGDATA_DIR from the build environment.

This section provides migration information for moving to the Yocto Project 2.0 Release from the prior release.

The default compiler is now GCC 5.2. This change has required fixes for compilation errors in a number of other recipes. 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 patch. The standard linux-yocto kernel source tree already has a workaround for the same issue. For further details, see and the porting guide at . Alternatively, you can switch back to GCC 4.9 or 4.8 by setting GCCVERSION in your configuration, as follows: GCCVERSION = "4.9%"

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 meta-multimedia. This change results in Qt4 having Phonon and Gstreamer support in QtWebkit disabled by default.

The following recipes have been moved or removed: bluez4: The recipe is obsolete and has been moved due to bluez5 becoming fully integrated. The bluez4 recipe now resides in meta-oe. gamin: The recipe is obsolete and has been removed. gnome-icon-theme: The recipe's functionally has been replaced by adwaita-icon-theme. Gstreamer 0.10 Recipes: Recipes for Gstreamer 0.10 have been removed in favor of the recipes for Gstreamer 1.x. insserv: The recipe is obsolete and has been removed. libunique: The recipe is no longer used and has been moved to meta-oe. midori: The recipe's functionally has been replaced by epiphany. python-gst: The recipe is obsolete and has been removed since it only contains bindings for Gstreamer 0.10. qt-mobility: The recipe is obsolete and has been removed since it requires Gstreamer 0.10, which has been replaced. subversion: All 1.6.x versions of this recipe have been removed. webkit-gtk: The older 1.8.3 version of this recipe has been removed in favor of webkitgtk.

The method by which BitBake's datastore handles overrides has changed. Overrides are now applied dynamically and bb.data.update_data() is now a no-op. Thus, bb.data.update_data() 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: All potential overrides are now visible in the variable history as seen when you run the following: $ bitbake -e d.delVar('varname') and d.setVar('varname', None) result in the variable and all of its overrides being cleared out. Before the change, only the non-overridden values were cleared.

The shell versions of the BitBake message functions (i.e. bbdebug, bbnote, bbwarn, bbplain, bberror, and bbfatal) are now connected through to their BitBake equivalents bb.debug(), bb.note(), bb.warn(), bb.plain(), bb.error(), and bb.fatal(), 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: 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 bbwarn, bberror, and so forth. Or, you might want to simply remove the calls. The bbfatal message function now suppresses the full error log in the UI, which means any calls to bbfatal where you still wish to see the full error log should be replaced by die or bbfatal_log.

The following recipes have had extra dev/dbg packages removed: acl apmd aspell attr augeas bzip2 cogl curl elfutils gcc-target libgcc libtool libxmu opkg pciutils rpm sysfsutils tiff xz All of the above recipes now conform to the standard packaging scheme where a single -dev, -dbg, and -staticdev package exists per recipe.

Maintenance tracking data for recipes that was previously part of meta-yocto has been moved to OE-Core. The change includes package_regex.inc and distro_alias.inc, which are typically enabled when using the distrodata class. Additionally, the contents of upstream_tracking.inc has now been split out to the relevant recipes.

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 bblayers.conf, and DISTRO_FEATURES changes. 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: SSTATE_PRUNE_OBSOLETEWORKDIR = "0"

The linux-yocto 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. Metadata processing has now been removed from the kernel-yocto class and the external Metadata repository yocto-kernel-cache, which has always been used to seed the linux-yocto "meta" branch. This separate linux-yocto cache repository is now the primary location for this data. Due to this change, linux-yocto 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 meta/recipes-kernel/linux/linux-yocto_4.1.bb recipe for an example.

The following QA checks have been added: Added a "host-user-contaminated" check for ownership issues for packaged files outside of /home. 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. Added an "invalid-chars" check for invalid (non-UTF8) characters in recipe metadata variable values (i.e. DESCRIPTION, SUMMARY, LICENSE, and SECTION). Some package managers do not support these characters. Added an "invalid-packageconfig" check for any options specified in PACKAGECONFIG that do not match any PACKAGECONFIG option defined for the recipe.

These additional changes exist: gtk-update-icon-cache has been renamed to gtk-icon-utils. The tools-profile IMAGE_FEATURES item as well as its corresponding packagegroup and packagegroup-core-tools-profile no longer bring in oprofile. Bringing in oprofile 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. The IMAGE_FSTYPES variable's default value now specifies ext4 instead of ext3. All support for the PRINC variable has been removed. The packagegroup-core-full-cmdline packagegroup no longer brings in lighttpd due to the fact that bringing in lighttpd 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 busybox.

This section provides migration information for moving to the Yocto Project 2.1 Release from the prior release.

Variable expressions, such as ${varname} 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 either expand the value of individual variables through d.getVar(). To alternatively expand more complex expressions, use d.expand().

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 OVERRIDES must now appear in lower-case characters (e.g. values for MACHINE, TARGET_ARCH, DISTRO, and also recipe names if _pn-recipename overrides are to be effective).

The expand parameter to getVar() and getVarFlag() previously defaulted to False if not specified. Now, however, no default exists so one must be specified. You must change any getVar() calls that do not specify the final expand parameter to calls that do specify the parameter. You can run the following sed command at the base of a layer to make this change: sed -e 's:\(\.getVar([^,()]*\)):\1, False):g' -i `grep -ril getVar *` sed -e 's:\(\.getVarFlag([^,()]*, [^,()]*\)):\1, False):g' -i `grep -ril getVarFlag *` 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.

EXTRA_OEMAKE now defaults to "" instead of "-e MAKEFLAGS=". Setting EXTRA_OEMAKE to "-e MAKEFLAGS=" by default was a historical accident that has required many classes (e.g. autotools, module) 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 EXTRA_OEMAKE back to "-e MAKEFLAGS=" or by explicitly setting any required variable value overrides using EXTRA_OEMAKE, 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.

The use of ${libdir}/${BPN} as libexecdir is different as compared to all other mainstream distributions, which either uses ${prefix}/libexec or ${libdir}. The use is also contrary to the GNU Coding Standards (i.e. ) that suggest ${prefix}/libexec and also notes that any package-specific nesting should be done by the package itself. Finally, having libexecdir change between recipes makes it very difficult for different recipes to invoke binaries that have been installed into libexecdir. The Filesystem Hierarchy Standard (i.e. ) now recognizes the use of ${prefix}/libexec/, giving distributions the choice between ${prefix}/lib or ${prefix}/libexec without breaking FHS.

For recipes inheriting the autotools class, ac_cv_sizeof_off_t is no longer cached in the site files for autoconf. The reason for this change is because the ac_cv_sizeof_off_t 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 autoconf, this change should not be a problem. However, if you have a recipe that bypasses the standard do_configure task from the autotools class and the software the recipe is building uses a very old version of autoconf, the recipe might be incapable of determining the correct size of off_t during do_configure. The best course of action is to patch the software as necessary to allow the default implementation from the autotools class to work such that autoreconf succeeds and produces a working configure script), and to remove the overridden do_configure task such that the default implementation does get used.

Previously, for image recipes the do_rootfs task assembled the filesystem and then from that filesystem generated images. With this Yocto Project release, image generation is split into separate do_image_* tasks for clarity both in operation and in the code. For most cases, this change does not present any problems. However, if you have made customizations that directly modify the do_rootfs task or that mention do_rootfs, you might need to update those changes. In particular, if you had added any tasks after do_rootfs, you should make edits so that those tasks are after the do_image_complete task rather than before the task so that the your added tasks run at the correct time. A minor part of this restructuring is that the post-processing definitions and functions have been moved from the image class to the rootfs-postcommands class. Functionally, however, they remain unchanged.

The following recipes have been removed in the 2.1 release: gcc version 4.8: Versions 4.9 and 5.3 remain. qt4: All support for Qt 4.x has been moved out to a separate meta-qt4 layer because Qt 4 is no longer supported upstream. x11vnc: Moved to the meta-oe layer. linux-yocto-3.14: No longer supported. linux-yocto-3.19: No longer supported. libjpeg: Replaced by the libjpeg-turbo recipe. pth: Became obsolete. liboil: Recipe is no longer needed and has been moved to the meta-multimedia layer. gtk-theme-torturer: Recipe is no longer needed and has been moved to the meta-gnome layer. gnome-mime-data: Recipe is no longer needed and has been moved to the meta-gnome layer. udev: Replaced by the eudev recipe for compatibility when using sysvinit with newer kernels. python-pygtk: Recipe became obsolete. adt-installer: Recipe became obsolete. See the "ADT Removed" section for more information.

The following classes have changed: autotools_stage: Removed because the autotools class now provides its functionality. Recipes that inherited from autotools_stage should now inherit from autotools instead. boot-directdisk: Merged into the image-vm class. The boot-directdisk class was rarely directly used. Consequently, this change should not cause any issues. bootimg: Merged into the image-live class. The bootimg class was rarely directly used. Consequently, this change should not cause any issues. packageinfo: Removed due to its limited use by the Hob UI, which has itself been removed.

The following changes have been made to the build system user interface: Hob GTK+-based UI: 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 "Using the Toaster Web Interface" section in the Yocto Project Toaster User Manual for more information on this interface. "puccho" BitBake UI: Removed because is unmaintained and no longer useful.

The Application Development Toolkit (ADT) has been removed because its functionality almost completely overlapped with the standard SDK and the extensible SDK. For information on these SDKs and how to build and use them, see the Yocto Project Software Development Kit (SDK) Developer's Guide.

The following changes have been made for the Poky distribution: The meta-yocto layer has been renamed to meta-poky to better match its purpose, which is to provide the Poky reference distribution. The meta-yocto-bsp layer retains its original name since it provides reference machines for the Yocto Project and it is otherwise unrelated to Poky. References to meta-yocto in your conf/bblayers.conf should automatically be updated, so you should not need to change anything unless you are relying on this naming elsewhere. The uninative 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. The uninative class is enabled through the meta/conf/distro/include/yocto-uninative.inc file, which for those not using the Poky distribution, can include to easily enable the same functionality. Alternatively, if you wish to build your own uninative tarball, you can do so by building the uninative-tarball recipe, making it available to your build machines (e.g. over HTTP/HTTPS) and setting a similar configuration as the one set by yocto-uninative.inc. 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. Disabling this library generation is accomplished through a meta/conf/distro/include/no-static-libs.inc, which for those not using the Poky distribution can easily include to enable the same functionality. 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: DISABLE_STATIC = "" The separate poky-tiny distribution now uses the musl C library instead of a heavily pared down glibc. Using glibc results in a smaller distribution and facilitates much greater maintainability because musl is designed to have a small footprint. If you have used poky-tiny and have customized the glibc configuration you will need to redo those customizations with musl when upgrading to the new release.

The following changes have been made to packaging: The runuser and mountpoint binaries, which were previously in the main util-linux package, have been split out into the util-linux-runuser and util-linux-mountpoint packages, respectively. The python-elementtree package has been merged into the python-xml package.

The following changes have been made to the tuning files: 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. Support for ARM OABI was deprecated in gcc 4.7. The tune-cortexm*.inc and tune-cortexr4.inc 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.

These additional changes exist: 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. 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. The devtool modify 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" option when running devtool modify. 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. The .debug 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 FILES_${PN}-dbg to pick up the resulting .debug directories as these directories are automatically found and added. Inaccurate disk and CPU percentage data has been dropped from buildstats output. This data has been replaced with getrusage() data and corrected IO statistics. You will probably need to update code that reads the buildstats data. The meta/conf/distro/include/package_regex.inc is now deprecated. The contents of this file have been moved to individual recipes. 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. The v86d/uvesafb has been removed from the genericx86 and genericx86-64 reference machines, which are provided by the meta-yocto-bsp 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 the file, you can simply add v86d to your image.