Qt5 development primer

[kkoehne]

@jmfairlie: I'm not working on Mac OS X, sorry. You should raise your problems (after verifying that the problem is still there in latest master branch of e.g. qtbase) on IRC/freenode, #qt-labs channel . Or you raise it on qt5-feedback@qt.nokia.com .

[jmfairlie]

Now I tried with Ubuntu 11.04 with an ATI gpu (might be relevant) and linker isn't able to find GL libraries. Indeed, for some reason, there is no /usr/lib/libGL.so in my machine (not sure if this is normal) but only in /usr/lib/mesa and /usr/lib/fglrx.

If I add "-opengl desktop" to configure then it shows the message:

The OpenGL functionality test failed!
You might need to modify the include and library search paths by editing
QMAKE_INCDIR_OPENGL, QMAKE_LIBDIR_OPENGL and QMAKE_LIBS_OPENGL in
.../qt5/qtbase/mkspecs/linux-g++.

If I follow the suggestion and add those lines to qtbase/mkspecs/linux-g++/qmake.conf :

QMAKE_LIBDIR_OPENGL = /usr/lib/fglrx
QMAKE_INCDIR_OPENGL = /usr/include/GL
QMAKE_LIBS_OPENGL = -lGL

It doesn't make a difference and linker is still unable to find the GL libraries, (I guess those macros are not being used)

However if I just add a symlink to any of the GL libs to /usr/lib it finally finds them.

Unfortunately, QtQuick2.0 examples (what I'm interested in) don't work either, this time qmlscene SEGFAULTS in a seemingly unrelated call ... I guess I'll need to wait until a more stable version comes out.

[kkoehne]

Ubuntu 11.04 is used heavily in the development teams, so this should really work out of the box, without any environment variable tinkering. The libgl1-mesa-dev should include the /usr/lib/libGL.so file, try installing this package. (Btw, you can find out which package provides which file by using the "apt-get file search" command).

For reference, this is the output "configure -nokia-developer -nomake examples -nomake demos -nomake tests" gives me on an Ubuntu 11.04:

@
Build type: linux-g++
Architecture: i386
Host architecture: i386
Platform notes:

        - Also available for Linux: linux-kcc linux-icc linux-cxx

Build .................. libs
Configuration .......... debug shared dll qpa largefile stl precompile_header mmx 3dnow sse sse2 sse3 ssse3 sse4_1 sse4_2 avx minimal-config small-config medium-config large-config full-config fontconfig xlib xcb-xlib phonon-backend accessibility opengl qpa reduce_exports clock-gettime clock-monotonic mremap getaddrinfo ipv6ifname getifaddrs inotify system-jpeg system-mng system-png png system-tiff system-freetype system-zlib nis cups glib gstreamer dbus openssl xcb alsa pulseaudio concurrent audio-backend svg v8 debug private_tests
Debug .................. yes
Qt 3 compatibility ..... no
QtDBus module .......... yes (run-time)
QtConcurrent code ...... yes
QtGui module ........... yes
QtScript module ........ yes
QtScriptTools module ... yes
QtXmlPatterns module ... yes
Phonon module .......... yes
Multimedia module ...... auto
SVG module ............. yes
WebKit module .......... yes
JavaScriptCore JIT ..... To be decided by JavaScriptCore
V8 module .............. yes
Declarative module ..... yes
Declarative debugging ...yes
Location module ........ no
Support for S60 ........ no
Symbian DEF files ...... no
STL support ............ yes
PCH support ............ yes
MMX/3DNOW/SSE/SSE2/SSE3. yes/yes/yes/yes/yes
SSSE3/SSE4.1/SSE4.2..... yes/yes/yes
AVX..................... yes
IPv6 ifname support .... yes
getaddrinfo support .... yes
getifaddrs support ..... yes
Accessibility .......... yes
NIS support ............ yes
CUPS support ........... yes
Iconv support .......... no
Glib support ........... yes
GStreamer support ...... yes
PulseAudio support ..... yes
Large File support ..... yes
GIF support ............ plugin
TIFF support ........... plugin (system)
JPEG support ........... plugin (system)
PNG support ............ yes (system)
MNG support ............ plugin (system)
zlib support ........... system
Session management ..... auto
OpenGL support ......... yes (Desktop OpenGL)
OpenVG support ......... no
MySQL support .......... plugin
SQLite support ......... plugin (qt)
OpenSSL support ........ yes (run-time)
Alsa support ........... yes
ICD support ............ no
libICU support ......... no
Xcb support ............ limited (old version)
@

[jmfairlie]

this is what I got, I'll check on Monday if getting rid of the differences makes any difference:
@
--- a/jean
+++ b/kkoehne
-QtDBus module .......... no
+QtDBus module .......... yes (run-time)
-Phonon module .......... no
+Phonon module .......... yes
-CUPS support ........... no
+CUPS support ........... yes
-GStreamer support ...... no
-PulseAudio support ..... no
+GStreamer support ...... yes
+PulseAudio support ..... yes
-MNG support ............ plugin (qt)
+MNG support ............ plugin (system)
+MySQL support .......... plugin
-OpenSSL support ........ no
-Alsa support ........... no
+OpenSSL support ........ yes (run-time)
+Alsa support ........... yes
@

[jmfairlie]

pulled current latest version:

commit 0a0d66efceb64bcacffbf733053834829c657df7
Date: Wed Oct 19 07:38:37 2011 +1000

and this time qmlscene spit some more info after segfault:

"Cannot create platform GL context, none of GLX, EGL, DRI2 is enabled"

This message directed me to:
http://comments.gmane.org/gmane.comp.lib.qt.qml/3060

which suggests to install libx11-xcb-dev. Indeed I didn't have it, so I installed, cleaned and rebuilt, and now it works.

If this package is required for qtdeclarative to work properly shouldn't configure notice it and mention it somehow?
Anyhow, Just added this info to the wiki page.

[qtd1d1]

The installation was successful, but when I try to compile my own application I get the following error:
QDeclarativeView: No such file or directory

Just read the windows needs python for QDeclarative. What packages do I need for Linux (Ubuntu 10.04) ?

Does anyone had similar problems?

[andreagrandi]

After compiling Qt5 I'd like to do a safe "make install" in my system. With "safe" I mean that I don't want to overwtite my Qt4 libs on my system so they should be installed in (for example) /opt/qt5 if it's possible.

I also would like to start packaging Qt5 in a Ubuntu PPA, but even if I've a little experience with packaging, I really don't know how to split an installation in multiple packages (I mean: qt-multimedia, qt-database, qt-tools ecc.... just to make you an example): should I take example from the actual Qt4 packages available in Ubuntu? Anyone want to help me? Thanks!

[qtd1d1]

How do you force qtbase/src/plugins/platforms/xcb to recompile?

[markc]

I get this at every dir level I tried on Archlinux x86_64...
@~qt5-git/qtbase git submodule update --init src/3rdparty/v8
You need to run this command from the toplevel of the working tree.@
I already have a libv8 3.6.5.1 as part of my system so would it possible for qtbase and whatever else needs libv8 to just link against my system version?

[ludde]

Hi! Trying to build Qt 5 for the first time, but I'm not getting very far...
Seems like the init-repository script is not working properly with the the --http option. All the repos are cloned using "http:", except for the qt3d repo which still tries to use "git:".
Very simple problem, but with my total lack of experience with perl, I'm not sure how to work around it... If anyone could give me a hint on how to get past this, by fixing init-repository, or doing some manual step, it would be most appreciated.

[markc]

What is the best way to incorporate qtwebkit into a qt5 build?
@...
[pid 30835] open(".../qt5-git/.git/modules/qtwebkit/refs/heads/master", O_RDONLY) = -1 ENOENT (No such file or directory)
[pid 30835] write(2, "fatal: Oops\n", 12fatal: Oops@

@ludde, I'm not sure why there is not some plain English instructions to clone the repo exactly, or a bash script, rather than buried inside an obfuscated perl script that doesn't seem to work. An example .git/config file would be more useful.

[ludde]

Managed to make init-repository clone all the modules (by fiddling a bit with the perl script, without really understanding what I was doing...).

Also managed to run configure. But compiling (using Microsoft Visual Studio 2005, on Windows 7, 64 bit) eventually fails:

@
c:\users\ludde\qt\qt5\qtbase\src\plugins\platforms\windows\qtwindowsglobal.h(178) : error C2065: 'WM_XBUTTONDOWN' : undeclared identifier
c:\users\ludde\qt\qt5\qtbase\src\plugins\platforms\windows\qtwindowsglobal.h(178) : error C2065: 'WM_XBUTTONDBLCLK' : undeclared identifier
c:\users\ludde\qt\qt5\qtbase\src\plugins\platforms\windows\qwindowscontext.h(74) : error C2059: syntax error : '<L_TYPE_raw>'
@

Any ideas on what might be causing this?

[kkoehne]

@ludde: I filed https://bugreports.qt.nokia.com/browse/QTBUG-23580 regarding your problems with the -http option. About the windows problems ... don't know, it compiles for me :( I guess you're better off subscribing to qt-development@qt-project.org, and posting your problems there.

[oneWonders]

While running
@./configure -developer-build -opensource -nomake examples -nomake tests@

i get this error partway through:

@Creating qmake. Please wait...
g++ -c -o project.o -pipe -DQMAKE_OPENSOURCE_EDITION -g -g -I. -Igenerators -Igenerators/unix -Igenerators/win32 -Igenerators/mac -Igenerators/integrity -I/home/daniel/qt5/qtbase/include -I/home/daniel/qt5/qtbase/include/QtCore -I/home/daniel/qt5/qtbase/include/QtCore/5.0.0 -I/home/daniel/qt5/qtbase/include/QtCore/5.0.0/QtCore -I/home/daniel/qt5/qtbase/src/corelib/global -I/home/daniel/qt5/qtbase/src/corelib/xml -I/home/daniel/qt5/qtbase/tools/shared -DQT_NO_PCRE -DQT_BUILD_QMAKE -DQT_BOOTSTRAPPED -DQT_NO_TEXTCODEC -DQT_NO_UNICODETABLES -DQT_NO_COMPONENT -DQT_NO_STL -DQT_NO_COMPRESS -I/home/daniel/qt5/qtbase/mkspecs/linux-g++ -DHAVE_QCONFIG_CPP -DQT_NO_THREAD -DQT_NO_QOBJECT -DQT_NO_GEOM_VARIANT -DQT_NO_DEPRECATED project.cpp
make: g++: Command not found
make: *** [project.o] Error 127
@

I am using ubuntu, does anyone know where i went wrong?
Sorry i'm rather new to all this :$

[dangelog]

Do you have gcc installed...?

[ludde]

Had this problem too. For some reason you need not only have gcc installed, but have it available as g++. This can be accomplished by installing the g++ package (and possibly also by just creating an alias from g++ to gcc, but I didn't try this).

[oneWonders]

Ah thanks, that works, i had gcc installed but not g++ it seems.

Strangely, i cannot run demos as even if i make the executables runnable, then i get something like this:
@Details: Failed to execute child process "/usr/bin/tea_service" (No such file or directory)@

after making the qt teaservice.desktop demo executable as a program in its right click properties and trying to run.
Somehow i get the impression that this is not what i am meant to be doimng anyway, as the idea that i would have to right click and change the permissions of all the demo files that i wanted to run doesn't seem the most fun so i guess i am trying to do it the wrong way :$

Also, i tried to compile qt creator and the qtquick3d demos myself and got errors.
(For example, for the qtquick3d):
@daniel@andy-desktop:~/qt_creator/what$ qmake /home/daniel/qt5/qtquick3d/demos/demos.pro
daniel@andy-desktop:~/qt_creator/what$ sudo make
cd quick3d/ && /home/daniel/qt5/qtbase/bin/qmake /home/daniel/qt5/qtquick3d/demos/quick3d/quick3d.pro -o Makefile
cd quick3d/ && make -f Makefile
make[1]: Entering directory /home/daniel/qt_creator/what/quick3d' cd model_viewer/ && /home/daniel/qt5/qtbase/bin/qmake /home/daniel/qt5/qtquick3d/demos/quick3d/model_viewer/model_viewer.pro -o Makefile cd model_viewer/ && make -f Makefile make[2]: Entering directory /home/daniel/qt_creator/what/quick3d/model_viewer'
g++ -c -pipe -g -Wall -W -D_REENTRANT -DQT_DECLARATIVE_LIB -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -DQT_SHARED -I../../../../qt5/qtbase/mkspecs/linux-g++ -I../../../../qt5/qtquick3d/demos/quick3d/model_viewer -I../../../../qt5/qtbase/include/QtCore -I../../../../qt5/qtbase/include/QtGui -I../../../../qt5/qtbase/include/QtWidgets -I../../../../qt5/qtdeclarative/include -I../../../../qt5/qtdeclarative/include/QtDeclarative -I../../../../qt5/qtbase/include -I../../../../qt5/qtbase/include/QtNetwork -I../../../../qt5/qtxmlpatterns/include -I../../../../qt5/qtxmlpatterns/include/QtXmlPatterns -I/usr/X11R6/include -I. -I../../../../qt5/qtquick3d/demos/quick3d/model_viewer -I. -o main.o ../../../../qt5/qtquick3d/demos/quick3d/model_viewer/main.cpp
In file included from ../../../../qt5/qtbase/include/QtGui/qopengl.h:1:0,
from ../../../../qt5/qtdeclarative/include/QtDeclarative/../../src/declarative/items/qquickcanvas.h:46,
from ../../../../qt5/qtdeclarative/include/QtDeclarative/qquickcanvas.h:1,
from ../../../../qt5/qtdeclarative/include/QtDeclarative/../../src/declarative/items/qquickview.h:46,
from ../../../../qt5/qtdeclarative/include/QtDeclarative/qquickview.h:1,
from ../../../../qt5/qtdeclarative/include/QtDeclarative/QQuickView:1,
from ../../../../qt5/qtquick3d/demos/quick3d/model_viewer/../qmlres.h:47,
from ../../../../qt5/qtquick3d/demos/quick3d/model_viewer/main.cpp:42:
../../../../qt5/qtbase/include/QtGui/../../src/gui/opengl/qopengl.h:69:21: fatal error: GL/gl.h: No such file or directory
compilation terminated.
make[2]: *** [main.o] Error 1
make[2]: Leaving directory /home/daniel/qt_creator/what/quick3d/model_viewer' make[1]: *** [sub-model_viewer-make_default] Error 2 make[1]: Leaving directory /home/daniel/qt_creator/what/quick3d'
make: *** [sub-quick3d-make_default] Error 2
@

Sorry to be a pain.

[bunjee]

Greetings guys,

On Windows 7 x64 I get the following:

@qwindowstheme.cpp: In member function 'virtual QVariant QWindowsTheme::themeHint(QPlatformTheme::ThemeHint) const': qwindowstheme.cpp:77:53: error: 'SPI_GETDROPSHADOW' was not declared in this scope@

It seems that the SPI_GETDROPSHADOW is under a WIN_NT_32 define.

[Philius]

I just restarted my attempt at building Qt5 after spending a day finding out that wayland isn't ready for Debian Wheezy amd64 yet.

By running configure with the "-v" switch I could see the auto-detection tests and their results - I needed to install libasound2-dev for Alsa.

Note:
@make confclean@

does nothing - "confclean" isn't a valid makefile target, although configure tells you to use this to clean up before another configure run.

Maybe someone could add
@confclean:
<tab>git submodule foreach --recursive 'git clean -dfx'@

to the right makefile to tie things up.

Also, see the
@qtbase/configure: 7201: [: x86_64: unexpected operator@

error after the "rm -f ..." entries below.

The error is
@if [ -n "$_SBOX_DIR" -a "$CFG_ARCH" == "arm" ]; then@

This is a "bashism" - something only bash understands.
Although /bin/sh was usually symlinked to /bin/bash, on Debian Wheezy /bin/sh -> dash.

"dash" and therefore "sh" doesn't recognise "[" and doesn't like "==".

@if test -n "$_SBOX_DIR" && test "$CFG_ARCH" = "arm"; then@

It occurs lots of times in this configure script - maybe in others too.

Somehow it muddles through. I'd recommend using "set -e" to catch these.

Anyway here's my configure output, after doing the recursive clean command above.

@

• /v3c/dev/Graphics/Qt/qt5/qtbase/configure -prefix /v3c/dev/Graphics/Qt/qt5/qtbase -no-wayland -opengl -no-glib -opensource -confirm-license -qpa -v
  Determining system architecture... (Linux:3.0.0-1-amd64:x86_64)
  64-bit AMD 80x86 (x86_64)
  'x86_64' is supported
  System architecture: 'x86_64'
  Host architecture: 'x86_64'
  Precompiled-headers support enabled.
  Symbol visibility control enabled.
  Symbolic function binding enabled.

This is the Qt Lighthouse Open Source Edition.

You are licensed to use this software under the terms of
the Lesser GNU General Public License (LGPL) versions 2.1.

You have already accepted the terms of the license.
@
bootstrapping and feature tests...

@
/v3c/dev/Graphics/Qt/qt5/qtbase/configure: 7201: [: x86_64: unexpected operator
Testing size of pointers ... (/v3c/dev/Graphics/Qt/qt5/qtbase/mkspecs/linux-g++-64 yes /v3c/dev/Graphics/Qt/qt5/qtbase /v3c/dev/Graphics/Qt/qt5/qtbase)
rm -f ptrsizetest.o
rm -f *~ core *.core
g++ -c -m64 -pipe -O2 -Wall -W -I../../../mkspecs/linux-g++-64 -I. -o ptrsizetest.o ptrsizetest.cpp
g++ -m64 -Wl,-O1 -o ptrsizetest ptrsizetest.o
Pointer size: 8
ln: failed to create symbolic link /v3c/dev/Graphics/Qt/qt5/qtbase/include/QtCore/qconfig.h': File exists ln: failed to create symbolic link /v3c/dev/Graphics/Qt/qt5/qtbase/include/Qt/qconfig.h': No such file or directory

    This target is using the GNU C++ compiler (linux-g++-64).

    Recent versions of this compiler automatically include code for
    exceptions, which increase both the size of the Qt libraries and
    the amount of memory taken by your applications.

    You may choose to re-run configure with the -no-exceptions
    option to compile Qt without exceptions. This is completely binary
    compatible, and existing applications will continue to work.

Build type: linux-g++-64
Architecture: x86_64
Host architecture: x86_64
Platform notes:

        - Also available for Linux: linux-kcc linux-icc linux-cxx

qmake vars .......... cat: .qmake.vars: No such file or directory
qmake switches .........
Build .................. libs examples tests
Configuration .......... release shared dll qpa largefile stl precompile_header mmx 3dnow sse sse2 sse3 ssse3 sse4_1 sse4_2 avx minimal-config small-config medium-config large-config full-config fontconfig xlib xrender xcb-render accessibility openvg opengl qpa reduce_exports reduce_relocations clock-gettime clock-monotonic mremap getaddrinfo ipv6ifname getifaddrs inotify system-jpeg system-png png system-tiff system-freetype system-zlib nis cups dbus openssl xcb alsa concurrent audio-backend svg v8 v8snapshot release
Debug .................. no
QtDBus module .......... yes (run-time)
QtConcurrent code ...... yes
QtGui module ........... yes
QtScript module ........ yes
QtScriptTools module ... yes
QtXmlPatterns module ... yes
Phonon module .......... no
Multimedia module ...... auto
SVG module ............. yes
WebKit module .......... yes
JavaScriptCore JIT ..... To be decided by JavaScriptCore
V8 module .............. yes
Declarative module ..... yes
Declarative debugging ...yes
Location module ........ no
STL support ............ yes
PCH support ............ yes
MMX/3DNOW/SSE/SSE2/SSE3. yes/yes/yes/yes/yes
SSSE3/SSE4.1/SSE4.2..... yes/yes/yes
AVX..................... yes
IPv6 ifname support .... yes
getaddrinfo support .... yes
getifaddrs support ..... yes
Accessibility .......... yes
NIS support ............ yes
CUPS support ........... yes
Iconv support .......... no
Glib support ........... no
GStreamer support ...... no
PulseAudio support ..... no
Large File support ..... yes
GIF support ............ plugin
TIFF support ........... plugin (system)
JPEG support ........... plugin (system)
PNG support ............ yes (system)
zlib support ........... system
Session management ..... auto
OpenGL support ......... yes (Desktop OpenGL)
OpenVG support ......... yes
MySQL support .......... plugin
PostgreSQL support ..... plugin
SQLite support ......... plugin (qt)
OpenSSL support ........ yes (run-time)
Alsa support ........... yes
libICU support ......... no
Xcb support ............ limited (old version)
Xrender support ........ yes
@
(continued...)

[Philius]

Here's a list of files I had to modify on my way to discovering that libQtdesigner is needed for qtbase/plugins/designer/libqwebview.so but wasn't built yet.

This needs "Qt += quick"
@
./qtwebkit/Tools/WebKitTestRunner/Target.pri
@

This needs to "#include <QNetworkCookie>"
@
./qtwebkit/Tools/QtTestBrowser/cookiejar.cpp
@

This uses " QTouchEvent::TouchPoint::Primary" - I commented it (and the "if" statement) out to get further.
@
./qtwebkit/Tools/MiniBrowser/qt/MiniBrowserApplication.cpp
@

This needs "Qt += quick"
@
./qtwebkit/Tools/MiniBrowser/qt/MiniBrowser.pro
@

This needs to "#include <QNetworkCookie>"
@
./qtwebkit/Source/WebKit/qt/WebCoreSupport/FrameNetworkingContextQt.cpp
@

These need "Qt += quick"
@
./qtwebkit/Source/api.pri
./qtwebkit/Source/tests.pri
@

This wasn't tested with "regular" OpenGL
@
./qtwebkit/Source/WebCore/platform/graphics/cairo/OpenGLShims.cpp
@

Here's the change I made to it.
@
#if PLATFORM(QT)
static void* getProcAddress(const char* procName)
{

• return QGLContext::currentContext()->getProcAddress(QString::fromLatin1(procName));

• return (void *)QGLContext::currentContext()

•    ->getProcAddress(QString::fromLatin1(procName));
  

}
#else
typedef void* (glGetProcAddressType) (const char procName);
@

These assume they're only included from within WebKit - untrue.
Yes, I later realized that this isn't the right place to change them.
@
./qtbase/include/QtWebKit/qwebview.h
./qtbase/include/QtWebKit/qwebframe.h
./qtbase/include/QtWebKit/qwebkitversion.h
./qtbase/include/QtWebKit/qwebpluginfactory.h
./qtbase/include/QtWebKit/qwebinspector.h
./qtbase/include/QtWebKit/qwebkitplatformplugin.h
./qtbase/include/QtWebKit/qwebhistoryinterface.h
./qtbase/include/QtWebKit/qwebsecurityorigin.h
./qtbase/include/QtWebKit/qwebelement.h
./qtbase/include/QtWebKit/qwebpage.h
./qtbase/include/QtWebKit/qwebdatabase.h
./qtbase/include/QtWebKit/qwebhistory.h
./qtbase/include/QtWebKit/qwebkitglobal.h
./qtbase/include/QtWebKit/qwebsettings.h
@

Hope this helps.