Qt5 development primer

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.

Philius

I had to choose between OpenGL and GL ES2 but I could also select xcb.

Isn't qpa building about being able to select between all of these at run-time?

On Debian Wheezy I've got the libraries and development packages installed to support OpenGL and GL ES2.

Also, maybe "build.stamp" and "install.stamp" files marking modules as built/installed could help "make" or "make install" skip modules entirely and speed things up.

If specifying "-prefix $PWD/qtbase" is your way of saying Qt5 isn't ready for "-prefix /usr" then you could have made that point a little more prominently.

sierdzio

Philius, I think it would be nice if you posted your findings to Qt development mailing list, where devs are likely to pick it up. And/ or modifying the "Building Qt5 from Git":http://developer.qt.nokia.com/wiki/Building_Qt_5_from_Git wiki page might be a good idea.

Philius

I re-subscribed and posted an email with a QtWebkit patch although my build still (eventually) fails.

I think that as long as the install prefix is inside the source tree (not to mention the build path!) you're going to have problems, so I won't try it again at least until these things change.

From trying to fix problems I noticed that there are several "Release" directories created in the source tree - it looks like someone was at least trying to do some whacky kind of out-of-source-while-still-in-source deal.

Do a "find . -type d -name Release" once you've tried to build it at least once to see the strangeness.

I also noticed that the build process was picking header files from the install path in preference to the source directory - I've got projects that use automake that don't do that (it's a shame automake can't do the same for libraries).

Then there's "make install" trying to copy files over themselves.

I'll stop here.

angrymango

On OSX I got stuck with a conflict of MacTypes.h

"http://code.google.com/p/webkit-mirror/source/detail?r=a84882c321ecf749f61a855f1538aeaf938b2340":http://code.google.com/p/webkit-mirror/source/detail?r=a84882c321ecf749f61a855f1538aeaf938b2340

Here are some links to patches that address some of the problems mentioned by Philius:

"https://gist.github.com/1647614":https://gist.github.com/1647614
"https://bug-76463-attachments.webkit.org/attachment.cgi?id=122778":https://bug-76463-attachments.webkit.org/attachment.cgi?id=122778

Philius

Those "QT += quick" are needed on Debian Wheezy because of
@
ld.bfd: "could not read symbols: Invalid operation" after indirect reference is unhelpful
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=629498
@

angrymango

I can confirm that all of changes mentioned by Philius are required to build on OSX.

I also needed to add - "QT += quick" to the following files:

./qtwebkit/Source/WebKit/qt/declarative/public.pri
./qtwebkit/Source/WebKit/qt/declarative/experimental/experimental.pri
./qtwebkit/Source/WebKit2/UIProcess/API/qt/tests/tests.pri

Philius - I think there are a few small mistakes in your earlier post which may be misleading to some - you say add "Qt += quick" which I believe should be "QT += quick" with upper case T

Philius

Yep.
While packaging my projects to get them into Debian I had my wrist slapped for referring to Qt as QT, which is QuickTime.
It must have stuck in my head.
They're spelled correctly in the patch, and anyway sometimes you have to append "quick" to the existing "QT =" or "QT +=" line.

angrymango

Very true about appending it in some cases.

I was wondering have you been testing qtwebkit at all? On OSX the build seems to be adding incorrect paths from the binaries to the dynamic libraries. I've fixed them up but MiniBrowser and QtTestBrowser are still not quite working properly yet. I'm going to look into it more later. I just wondered if the situation was looking any better on Linux? I'm going to try building on Ubuntu next.

Philius

I just started a shadow build.
Here's the makefile (same dir as qt5).
@
all: config
cd qt5-build;
export PATH="${PATH}:$$(readlink -f qtbase/bin)";
make -j 2 && make install

config: #clean
mkdir -p qt5-build
mkdir -p qt5-install
cd qt5-build;
if test ! -f config.stamp; then
../qt5/configure -prefix $$(readlink -f ../qt5-install) -no-wayland
-no-openvg -opengl es2 -opensource -confirm-license -v
-I /usr/include/gstreamer-0.10
-I /usr/include/glib-2.0
-I /usr/lib/x86_64-linux-gnu/glib-2.0/include
-I /usr/include/libxml2
2>&1 | tee make.txt;
touch config.stamp;
else
echo "Config target already done.";
fi

clean:
#cd qt5; git submodule foreach --recursive 'git clean -dfx'
rm -fr qt5-build
@

The includes are for gstreamer support.

It looks like OpenVG and Phonon aren't ready yet.
The error for them is "QMAKESPEC has not been set, so configuration cannot be deduced".

I'll report back when it's done.

Philius

It looks like the build system doesn't track configure changes - gstreamer seems to require phonon.

I'll "make clean" and "try" yet again.

Philius

Out of source builds definitely don't work, although this could change with new updates.

I'm not sure why the separate packages aren't "configure && make && make install" -able individually.
Maybe this is just to get them built quicker, but then they aren't really separate packages.

Also, providing text instructions that (currently) conflict with the README in git isn't helpful.
One of them should change.

Next, there should be a top-level "make" script which builds the tested configuration.
export "$ROOT" to the absolute path to the qt5 directory for the comments below.
I added
@export QMAKESPEC="linux-g++-64"@

otherwise svg and phonon modules fail.

I added
@-prefix ${ROOT}/qtbase@

otherwise qmake won't find qmodule.pri.

I added
@export PATH="${ROOT}/qtbase/bin:${PATH}"@

To use the binaries built in the build tree and not those installed on my system.

It still fails with the following error:
@
../../../../Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp: In member function ‘void WebCore::GraphicsContext3DPrivate::blitMultisampleFramebuffer() const’:
../../../../Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp:261:23: error: ‘GL_READ_FRAMEBUFFER_EXT’ was not declared in this scope
../../../../Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp:262:23: error: ‘GL_DRAW_FRAMEBUFFER_EXT’ was not declared in this scope
make[6]: *** [obj/release-static/platform/graphics/qt/GraphicsContext3DQt.o] Error 1
@

GL_READ_FRAMEBUFFER_EXT is defined in GL/glext.h but not in OpenGL ES2, at least not in Wheezy amd64.

Philius

Sorry for editing my messages but the ground is moving under me.

I rebuilt with "regular" OpenGL and found one more problem:
qtwebkit-examples-and-demos/examples/browser/cookiejar.cpp is missing "#include <QNetworkCookie>".

I sent a message to development@qt-project.org so hopefully the patch (along with my patch for qtwebkit) should find their way into GIT soon.

Other than that, with the approach detailed in my previous post, the build succeeded.

It took about 4 hours with "make -j 2" on my dual core laptop with both cores running at 1.867 GHz.