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= Build requirements =
+
= Build KDE Frameworks and Applications =
This section provides information about '''hard''' (required) and '''optional''' software packages needed to build the KDE Framework.
 
  
=== Dependencies ===
+
== Design features ==
*'''deb-based distributions (Debian, Ubuntu...):'''
+
Qt and most KDE software are written in C++ whereas its "competitor" GTK is written in C making it very portable and easy to produce language bindings for (for Ruby, Python, Bash etc.). So it is possible to write a complete GTK GUI app in Bash script, but so far that has not been done for Qt.
$ sudo apt-get build-dep qt4-x11
 
$ sudo apt-get install libbz2-dev libxslt-dev libxml2-dev shared-mime-info oxygen-icon-theme libgif-dev libvlc-dev libvlccore-dev doxygen gperf bzr
 
  
*'''OpenSuSE:''' All the necessary dependencies:
+
== Safety Precautions ==
  $ sudo zypper si -d libqt4
+
Configuring your build environment is the single most important step in building KDE software.  Luckily, KDE Frameworks development libraries are packaged by most major distributions. In general, building and installing user space programs such as Calligra can be done safely without altering any system files. Whenever possible, it is recommended that you build KDE using your normal user account. Unless you are interested in changing the behavior of your system, you should build with a normal account.  Even if you are a a KWin or Plasma developer wishing to test a full Plasma session with compositing effects, there are ways to construct the desired testing bed entirely within your normal user account, e.g. running Plasma through a nested X server using xypher.
  $ sudo zypper in libbz2-devel libxslt-devel libxml2-devel shared-mime-info oxygen-icon-theme giflib-devel vlc-devel doxygen gstreamer-0_10-devel gstreamer-0_10-plugins-base-devel docbook-xml-slides docbook-xsl-stylesheets xcb-util-keysyms-devel
 
  
*'''Fedora:''' All the dependencies used for building frameworks can be installed by running:
+
However, to permanently alter your Plasma desktop environment through new System Configuration Modules and the like, you will often need to install shared libraries and other files in system folders. In these cases, bad installation can render your system unstable or your desktop environment unusable.  '''Always take caution before executing any commands as root!'''  A <code>sudo make install</code> '''can not always be undone by''' a simple <code>sudo make uninstall</code>  . Technologies like containerization may help solve these problems in the future, but current distribution systems have no way to monitor the alterations you make to system shared libraries as the system administrator. Another option is to use snapshots of a BTRfs formatted system harddisk and use snapper-GUI to roll back in case of an error. Always keep records of what you are doing and make sure you know how to access the install logs to give yourself a better chance of reverting files by hand if necessary. And of course, please keep high quality, frequent backups of your data.
$ sudo yum-builddep qt phonon-backend-vlc phonon-backend-gstreamer
 
  $ sudo yum install bzip2-devel libxslt-devel libxml2-devel shared-mime-info oxygen-icon-theme giflib-devel doxygen xcb-util-keysyms-devel perl-Pod-Usage "*xcb*-devel" perl-XML-Parser
 
  
*'''Arch Linux:''' All the dependencies used for building frameworks can be installed by running:
+
== Configuration scripts  ==
$ sudo pacman -Sy phonon-qt5 qt5-webkit qt5-svg qt5-x11extras enchant jasper openexr libutempter docbook-xsl shared-mime-info giflib libxss upower udisks2
+
A set of configuration scripts and bash commands are provided as a recommended configuration when building KDE software manually.  If you use these as provided then your build will be a lot easier and it will be easier for you to find support online. The one disadvantage to these scripts is that they hide important details from you which you may want to learn about. However the scripted and by-hand methods are completely interchangeable so once you are comfortable building KDE using the scripts you can learn more by doing everything yourself.
$ <your_AUR_helper> kf5-attica-git libdbusmenu-qt5 kf5-akonadi-git kf5-polkit-git
 
  
=== Qt 5 ===
+
If you want to do the work by hand you can follow the [[/Details|detailed instructions]] else continue here on.
To build all of qt5 execute:
 
  $ git clone git://anongit.kde.org/qt/qt5.git --branch stable
 
  $ cd qt5
 
  $ ./init-repository
 
  $ ./configure -prefix $PWD/qtbase -opensource -confirm-license -developer-build -nomake tests -nomake examples -dbus -no-separate-debug-info -xcb -qpa xcb -no-gtkstyle
 
  $ make
 
  
To update qt5 later:
+
== Install required devel packages ==
  $ git pull
 
  $ git submodule update
 
  
To switch to stable branch if you had dev branch (now kf5 depends against 5.2)
+
This section provides information about '''required''' and '''optional''' software packages needed to build the KDE applications.
$ git checkout stable
 
$ git pull
 
$ git submodule update
 
  
If you saw changes (i.e. qt5.git got updated since last time),
+
[https://www.qt.io/ Qt5] is the base of KDE software. Your distro provides suitable devel packages containing prominently the Qt C++ header files below /usr/include/****'''.h''' . Optionally, you can [[/OwnQt5| build your own Qt5]].
  $ ./configure [...same as above...]
 
  $ make
 
  $ echo $?    # you should make extra sure that 'make' didn't abort with an error, especially when using -j
 
  
Experimental and not officially supported: if you don't have enough time and disk space for all of qt5, you could restrict yourself to separate checkouts of qtbase.git, qtsvg.git and qtx11extras.git, this is enough to build  frameworks/* (but not enough for plasma-framework).  
+
Follow this page to [[/Install the dependencies|install the required dependencies]].
  
<b>NOTE for ArchLinux users</b>: qtwebkit uses python to generate some files, but it uses python2 syntax. So you have to either [https://projects.archlinux.org/svntogit/packages.git/plain/trunk/use-python2.patch?h=packages/qt5 patch the qtwebkit code] or make /usr/bin/python point to /usr/bin/python2. See also https://wiki.archlinux.org/index.php/Python
+
== Git remote prefix ==
 +
See [[Get Involved/development#Configure Git]]
  
= Runtime setup =
+
== kdesrc-build ==
To use your new KF5 install prefix (let's call it $KF5) :
+
See [[Get Involved/development#Set up kdesrc-build]]
<pre>
+
 
export KF5=<path to your intended frameworks install directory>
+
= Testing =
export QTDIR=<path to your qt5 sources>/qtbase
+
== Running unit tests ==
export XDG_DATA_DIRS=$KF5/share:$XDG_DATA_DIRS:/usr/share
+
Unit tests are ran from the build dir of each framework; you should first <code>cd</code> into it.
export XDG_CONFIG_DIRS=$KF5/etc/xdg:$XDG_CONFIG_DIRS:/etc/xdg
+
 
export PATH=$KF5/bin:$QTDIR/bin:$PATH
+
You need a separate DBus session because the dbus server needs to have the right value of XDG_DATA_DIRS, in order to find $KF5/share/dbus-1/services for starting services (e.g. kded5).
export QT_PLUGIN_PATH=$KF5/lib/plugins:$KF5/lib64/plugins:$KF5/lib/x86_64-linux-gnu/plugins:$QTDIR/plugins:$QT_PLUGIN_PATH
+
 
  (lib64 instead of lib, on OpenSUSE and similar)
+
<syntaxhighlight lang="bash">
export QML2_IMPORT_PATH=$KF5/lib/qml:$KF5/lib64/qml:$KF5/lib/x86_64-linux-gnu/qml:$QTDIR/qml
+
$ eval `dbus-launch`
export KDE_SESSION_VERSION=5
+
$ kdeinit5
export KDE_FULL_SESSION=true
+
$ make test
</pre>
+
</syntaxhighlight>
 +
 
 +
'''Note:''' Regular apps will start kdeinit5 automatically. The reason it has to be started by hand when running unit tests is some strange interaction with ctest.
 +
 
 +
'''Warning:''' never start a KDE 4 application in this separate DBus session. It would conflict with your running Plasma 4 desktop.
 +
 
 +
'''Note:''' <tt>KDE_FULL_SESSION=true</tt> is needed to make sure that the correct QPA will be loaded.
 +
 
 +
Many of the tests require an X server, and will pop up windows briefly. An easy way to allow these tests to run without interfering with your normal X session is to do
 +
 
 +
<syntaxhighlight lang="bash">
 +
$ xvfb-run -s '-screen 0 1024x768x24' make test
 +
</syntaxhighlight>
 +
 
 +
The -s argument tells Xvfb to set the first screen to be 1024x768 pixels, with a depth of 24; at least one test requires a depth greater than 8. In this case, if you also ensure <tt>DBUS_SESSION_BUS_ADDRESS</tt> is not set, the tests should not find your existing DBus session, and instead launch a new DBus instance.
 +
 
 +
Note that the KWindowSystem tests require a NETWM-compatible window manager to be running.  One way to do this is to create a script to run such a window manager, followed by whatever is passed to it.  For example, if you have the window manager [http://awesome.naquadah.org/ awesome] installed, you could create a script called <tt>awesome-run</tt> as follows:  
 +
 
 +
<syntaxhighlight lang="bash">
 +
#!/bin/sh
 +
awesome &
 +
exec "$@"
 +
</syntaxhighlight>
 +
 
 +
and then run the tests as
 +
 
 +
<syntaxhighlight lang="bash">
 +
$ xvfb-run -s '-screen 0 1024x768x24' /path/to/awesome-run make test
 +
</syntaxhighlight>
 +
 
 +
If you want to publish your test results, instead of "make test" run
 +
 
 +
<syntaxhighlight lang="bash">
 +
$ make Experimental
 +
</syntaxhighlight>
 +
 
 +
The test results will appear on http://my.cdash.org/index.php?project=&lt;projectname&gt;
 +
 
 +
== Testing Plasma ==
 +
 
 +
See [[Get Involved/development#Plasma]]
 +
 
 +
= Troubleshooting =
 +
 
 +
== Compilation: how to quickly solve build problems ==
 +
See [[Get Involved/development#How to solve build problems]]
 +
 
 +
== Runtime: Segfault when a sound is about to play (e.g. for a message box) ==
 +
(added: 2015-02-27)
  
Note that LD_LIBRARY_PATH isn't set. You shouldn't set it, the builtin rpath works magic instead, and if you set it you'll have issues when running tools that use uninstalled libs while building frameworks (e.g. meinproc, kconfig_compiler...)
+
Example of the problem: open kate, edit some file without saving, Ctrl+W to close, a message box is about to appear and the then segfault:
  
To use separate user settings for KF5:
 
 
<pre>
 
<pre>
export XDG_DATA_HOME=$HOME/.local5
+
kate(9037)/default KNotificationManager::notify: Calling notify on "Sound"
export XDG_CONFIG_HOME=$HOME/.config5
+
Segmentation fault
export XDG_CACHE_HOME=$HOME/.cache5
 
 
</pre>
 
</pre>
  
To be able to compile other stuff on top of KF5:
+
This command can solve the problem:
<pre>
 
export CMAKE_PREFIX_PATH=$KF5:$CMAKE_PREFIX_PATH
 
</pre>
 
  
To get more information out of qDebug statements (i.e. make it more like kDebug) :
+
<syntaxhighlight lang="bash">
<pre>
+
$ sudo /usr/lib64/vlc/vlc-cache-gen -f /usr/lib64/vlc/plugins
export QT_MESSAGE_PATTERN='%{appname}(%{pid})/%{category} %{function}: %{message}'
+
</syntaxhighlight>
</pre>
 
or even better, to get colors:
 
<pre>
 
c=`echo -e "\033"`
 
export QT_MESSAGE_PATTERN="%{appname}(%{pid})/(%{category}) $c[31m%{if-debug}$c[34m%{endif}%{function}$c[0m: %{message}"
 
unset c
 
</pre>
 
  
Don't bother with KDEDIR and KDEHOME etc. this stuff isn't used anymore.
+
See also:
 +
* [[Plasma/5.1_Errata]]
 +
* https://forum.kde.org/viewtopic.php?f=289&t=122996
  
=== Git remote prefix ===
+
Alternative: go to kf5/build/kdesupport/phonon/phonon-vlc/ and exec `make uninstall`
Let's setup a "kde:" prefix for git commands. Add the following text to your ~/.gitconfig:
 
  [url "git://anongit.kde.org/"]
 
    insteadOf = kde:
 
  [url "ssh://[email protected]/"]
 
    pushInsteadOf = kde:
 
  
= Build KDE Frameworks and its dependencies =
+
== Runtime: kded5 crashes because of some component ==
== Clone kdesrc-build ==
+
(added: 2015-Jan)
First you need kdesrc-build, it can be done with the following commands:
 
<pre>
 
mkdir -p extragear/utils
 
git clone kde:kdesrc-build extragear/utils/kdesrc-build
 
ln -s extragear/utils/kdesrc-build/kdesrc-build .
 
</pre>
 
  
== Download the configuration file ==
+
'''Situation:'''
At this point,
+
kded5 is started but crashes because of some dependency. Stacktraces show for example `bluedevil` as possible cause.
# download http://www.davidfaure.fr/kde/kf5-qt5-kdesrc-buildrc into your source dir
 
# rename it to '''kdesrc-buildrc'''
 
You can use this command:
 
<pre>
 
wget "http://www.davidfaure.fr/kde/kf5-qt5-kdesrc-buildrc" -O "kdesrc-buildrc"
 
</pre>
 
== Adjust the paths ==
 
Take a look at those lines in the configuration file you've downloaded:
 
<pre>
 
  qtdir /d/qt/5/kde/qtbase
 
  source-dir /d/kde/src/5
 
  build-dir /d/kde/build/5
 
  kdedir /d/kde/inst/kde_frameworks
 
</pre>
 
and adjust the paths the way you want.
 
* qtdir = where qt5 sources are located
 
* source-dir = where KDE Frameworks 5 sources should be downloaded
 
* build-dir = where KDE Frameworks 5 should be built
 
* kde-dir = your KDE Frameworks 5 installation directory
 
  
== Build kdesrc-build ==
+
'''Goal 1: Disable the component to verify it as crash cause.'''
{{Note|Note that this script uses GIT and Bazaar to download the sources, so ensure you have both installed. }}
 
You just have to run <code>./kdesrc-build</code> to build the KDE Frameworks.
 
It is the preferred way of building KDE Frameworks.  
 
  
If you want you can also do the work by hand following the detailed instructions: [[Frameworks/Building/Details]].
+
Steps:
  
== Use project neon 5 tools ==
+
# Locate bluedevil files using <code>locate bluedevil</code>, for example.
Project Neon 5 in KUbuntu provides neon5-env and neon5-cmake tools which makes building KDE Frameworks easy. For more details see: http://community.kde.org/Frameworks/Building/ProjectNeon5
+
# Among the files there is <tt>kde/usr/share/kservices5/kded/bluedevil.desktop</code>. Remove it. If it was the cause, kded should stop crashing
  
= Running unit tests =
+
'''Goal 2: Remove bluedevil from kdesrcbuild until it gets fixed.'''
Unit tests are ran from the build dir of each framework, you should first cd into it.
 
  
You need a separate DBus session because the dbus server needs to have the right value of XDG_DATA_DIRS, in order to find $KF5/share/dbus-1/services for starting services (e.g. kded5).
+
Steps:
  
 +
# Search through the <code>dev/kf5/src/extragear/utils/kdesrc-build/*-build-include</code> files to find the component. In this case, it was found in kf5-workspace-build-include.
 +
# Comment it out:
 
<pre>
 
<pre>
eval `dbus-launch`
+
# module-set kf5-bluetooth-management
kdeinit5
+
#    repository kde-projects
make test
+
#    use-modules libbluedevil bluedevil
 +
# end module-set
 
</pre>
 
</pre>
  
Warning: never start a KDE4 application in this separate DBus session, it would conflict with your running KDE4 desktop.
+
Further calls of <code>kdesrc-build</code> will not include the component.
Note: KDE_FULL_SESSION=true is needed to make sure that the correct QPA will be loaded.
+
 
 +
== Get more help ==
  
Many of the tests require an X server, and will pop up windows briefly. An easy way to allow these tests to run without interfering with your normal X session is to do <pre>
+
If you still have trouble with the building process or runtime setup, you can contact people as described in [[Get_Involved/development#Communicating_with_the_team|Communicating with the team]].
xvfb-run -s '-screen 0 1024x768x24' make test
+
 
</pre>
+
Feel free to join us by visiting [irc://irc.freenode.net/#kde-devel #kde-devel on Freenode]. A web-based client can be found at https://kiwiirc.com/client/irc.freenode.org/kde-devel
(the -s argument tells Xvfb to set the first screen to be 1024x768 pixels, with a depth of 24; at least one test requires a depth greater than 8)In this case, if you also ensure <tt>DBUS_SESSION_BUS_ADDRESS</tt> is not set, the tests should not find your existing D-Bus session, and instead launch a new D-Bus instance.
+
 
 +
= Alternative building methods =
 +
 
 +
== Kubuntu CI ==
 +
[[Kubuntu/PPAs#Kubuntu_Continuous_Integration_.28CI.29|Kubuntu CI]] (replaces Project Neon 5) provides packages of KDE Git master for KDE Frameworks and Plasma 5Install them on your Kubuntu system to work with KDE Git.
  
Note that the KWindowSystem tests require a NETWM-compatible window manager to be running.  One way to do this is to create a script to run such a window manager, followed by whatever is passed to it.  For example, if you have the window manager [http://awesome.naquadah.org/ awesome] installed, you could create a script called <tt>awesome-run</tt> as follows: <syntaxhighlight lang="bash">
+
== openSUSE Build Service ==
#!/bin/sh
+
[https://en.opensuse.org/SDB:KDE_repositories#Unstable_Frameworks.2C_Plasma_and_Applications The openSUSE Build Service] provides packages of KDE Git master for KDE Frameworks, Plasma, Applications and Extragear. It offers repositories for Tumbleweed and the latest stable (Leap) release.
awesome &
 
 
</syntaxhighlight>
 
and then run the tests as <pre>
 
xvfb-run -s '-screen 0 1024x768x24' /path/to/awesome-run make test
 
</pre>
 
  
If you want to publish your test results, instead of "make test" run <pre>
+
== Docker ==
make Experimental
+
The docker container keeps the target KDE separate from the working installation, so no "contamination" with unstable code can occur.
</pre>
+
* [[/Alternatives | Build with docker]]
The test results will appear on http://my.cdash.org/index.php?project=&lt;projectname&gt;
 

Latest revision as of 15:38, 22 June 2019

Build KDE Frameworks and Applications

Design features

Qt and most KDE software are written in C++ whereas its "competitor" GTK is written in C making it very portable and easy to produce language bindings for (for Ruby, Python, Bash etc.). So it is possible to write a complete GTK GUI app in Bash script, but so far that has not been done for Qt.

Safety Precautions

Configuring your build environment is the single most important step in building KDE software. Luckily, KDE Frameworks development libraries are packaged by most major distributions. In general, building and installing user space programs such as Calligra can be done safely without altering any system files. Whenever possible, it is recommended that you build KDE using your normal user account. Unless you are interested in changing the behavior of your system, you should build with a normal account. Even if you are a a KWin or Plasma developer wishing to test a full Plasma session with compositing effects, there are ways to construct the desired testing bed entirely within your normal user account, e.g. running Plasma through a nested X server using xypher.

However, to permanently alter your Plasma desktop environment through new System Configuration Modules and the like, you will often need to install shared libraries and other files in system folders. In these cases, bad installation can render your system unstable or your desktop environment unusable. Always take caution before executing any commands as root! A sudo make install can not always be undone by a simple sudo make uninstall . Technologies like containerization may help solve these problems in the future, but current distribution systems have no way to monitor the alterations you make to system shared libraries as the system administrator. Another option is to use snapshots of a BTRfs formatted system harddisk and use snapper-GUI to roll back in case of an error. Always keep records of what you are doing and make sure you know how to access the install logs to give yourself a better chance of reverting files by hand if necessary. And of course, please keep high quality, frequent backups of your data.

Configuration scripts

A set of configuration scripts and bash commands are provided as a recommended configuration when building KDE software manually. If you use these as provided then your build will be a lot easier and it will be easier for you to find support online. The one disadvantage to these scripts is that they hide important details from you which you may want to learn about. However the scripted and by-hand methods are completely interchangeable so once you are comfortable building KDE using the scripts you can learn more by doing everything yourself.

If you want to do the work by hand you can follow the detailed instructions else continue here on.

Install required devel packages

This section provides information about required and optional software packages needed to build the KDE applications.

Qt5 is the base of KDE software. Your distro provides suitable devel packages containing prominently the Qt C++ header files below /usr/include/****.h . Optionally, you can build your own Qt5.

Follow this page to install the required dependencies.

Git remote prefix

See Get Involved/development#Configure Git

kdesrc-build

See Get Involved/development#Set up kdesrc-build

Testing

Running unit tests

Unit tests are ran from the build dir of each framework; you should first cd into it.

You need a separate DBus session because the dbus server needs to have the right value of XDG_DATA_DIRS, in order to find $KF5/share/dbus-1/services for starting services (e.g. kded5).

 $ eval `dbus-launch`
 $ kdeinit5
 $ make test

Note: Regular apps will start kdeinit5 automatically. The reason it has to be started by hand when running unit tests is some strange interaction with ctest.

Warning: never start a KDE 4 application in this separate DBus session. It would conflict with your running Plasma 4 desktop.

Note: KDE_FULL_SESSION=true is needed to make sure that the correct QPA will be loaded.

Many of the tests require an X server, and will pop up windows briefly. An easy way to allow these tests to run without interfering with your normal X session is to do

 $ xvfb-run -s '-screen 0 1024x768x24' make test

The -s argument tells Xvfb to set the first screen to be 1024x768 pixels, with a depth of 24; at least one test requires a depth greater than 8. In this case, if you also ensure DBUS_SESSION_BUS_ADDRESS is not set, the tests should not find your existing DBus session, and instead launch a new DBus instance.

Note that the KWindowSystem tests require a NETWM-compatible window manager to be running. One way to do this is to create a script to run such a window manager, followed by whatever is passed to it. For example, if you have the window manager awesome installed, you could create a script called awesome-run as follows:

#!/bin/sh
awesome &
exec "[email protected]"

and then run the tests as

$ xvfb-run -s '-screen 0 1024x768x24' /path/to/awesome-run make test

If you want to publish your test results, instead of "make test" run

$ make Experimental

The test results will appear on http://my.cdash.org/index.php?project=<projectname>

Testing Plasma

See Get Involved/development#Plasma

Troubleshooting

Compilation: how to quickly solve build problems

See Get Involved/development#How to solve build problems

Runtime: Segfault when a sound is about to play (e.g. for a message box)

(added: 2015-02-27)

Example of the problem: open kate, edit some file without saving, Ctrl+W to close, a message box is about to appear and the then segfault:

 kate(9037)/default KNotificationManager::notify: Calling notify on "Sound"
 Segmentation fault

This command can solve the problem:

 $ sudo /usr/lib64/vlc/vlc-cache-gen -f /usr/lib64/vlc/plugins

See also:

Alternative: go to kf5/build/kdesupport/phonon/phonon-vlc/ and exec `make uninstall`

Runtime: kded5 crashes because of some component

(added: 2015-Jan)

Situation: kded5 is started but crashes because of some dependency. Stacktraces show for example `bluedevil` as possible cause.

Goal 1: Disable the component to verify it as crash cause.

Steps:

  1. Locate bluedevil files using locate bluedevil, for example.
  2. Among the files there is kde/usr/share/kservices5/kded/bluedevil.desktop. Remove it. If it was the cause, kded should stop crashing

Goal 2: Remove bluedevil from kdesrcbuild until it gets fixed.

Steps:

  1. Search through the dev/kf5/src/extragear/utils/kdesrc-build/*-build-include files to find the component. In this case, it was found in kf5-workspace-build-include.
  2. Comment it out:
 # module-set kf5-bluetooth-management
 #     repository kde-projects
 #     use-modules libbluedevil bluedevil
 # end module-set

Further calls of kdesrc-build will not include the component.

Get more help

If you still have trouble with the building process or runtime setup, you can contact people as described in Communicating with the team.

Feel free to join us by visiting #kde-devel on Freenode. A web-based client can be found at https://kiwiirc.com/client/irc.freenode.org/kde-devel

Alternative building methods

Kubuntu CI

Kubuntu CI (replaces Project Neon 5) provides packages of KDE Git master for KDE Frameworks and Plasma 5. Install them on your Kubuntu system to work with KDE Git.

openSUSE Build Service

The openSUSE Build Service provides packages of KDE Git master for KDE Frameworks, Plasma, Applications and Extragear. It offers repositories for Tumbleweed and the latest stable (Leap) release.

Docker

The docker container keeps the target KDE separate from the working installation, so no "contamination" with unstable code can occur.


This page was last edited on 22 June 2019, at 15:38. Content is available under Creative Commons License SA 4.0 unless otherwise noted.