Qwt version conflict QTCREATOR - c++

I'm having trouble deploying .exe generated with QtCreator on Ubuntu 14.04. I got several versions of qwt installed (and i need those, one compiled with qt4 the other with qt5).
Problem is, i don't know why but Qt seems to link the wrong version of qwt to my .exe whatever i do .. When i use LDD on my .exe, it always show /usr/lib/libqwt.so.6. Thing is i'm linking the version i need in my .pro like this :
LIBS += -L/usr/local/qwt-6.1.2/lib/ -lqwt
And in project configuration i set LD_LIBRARY_PATH with /usr/local/qwt-6.1.2/lib
Still my .exe doesn't link to the right library.
Any idea why and how to fix this ? It causes segmentation fault on launch of course as my program is compiled with qt5 and not qt4..
Thanks in advance

You can try adding a runtime path to the linker flags. In your .pro file you can add the following line (Its probably worth printing your QMAKE_LFLAGS in your pro file as well):
QMAKE_LFLAGS += "-Wl,-rpath,/usr/local/qwt-6.1.2/lib/"
message ("QMAKE_LFLAGS = $$QMAKE_LFLAGS")
Re-compile and then run ldd again. During runtime also ldd) your program should now point to this location first.
Note
This is assuming that you are using a gnu compiler!

I sorted out my problem, seems like settings the environment variables in QtCreator is not enough. You have to do it in the terminal aswell before launching the .exe, that was my bad.
Just had to set LD_LIBRARY_PATH correctly.

Related

QT The program can't start because libgcc_s_dw2-1.dll is missing

I know this has been asked before but I can't seem to find an answer.
I just have a little hello world console program basically I wrote in c++ with qt creator. When I try to run the executable I get "The program can't start because libgcc_s_dw2-1.dll is missing from your computer. Try reinstalling to fix this problem."
I don't understand why this dll is even necessary for a little program like this. I tried adding these flags as suggested elsewhere:
QMAKE_CXXFLAGS += -static -static-libgcc -static-libstdc++
and it still happens. Other people have suggested adding the directory whee the dll is located to my path but I'd like to actually give this program to someone else without them needing the dll.
I know this is an old question, and you probably found a solution that worked for you, but I stumbled upon this after a day spent trying to build a statically linked (standalone) application with Qt 5.9.1/MinGW32-5.3.0-32bit.
After building a static version of Qt, it was finally these dynamically linked libraries that MinGW / GCC pulled in that was still holding me back:
libgcc_s_dw2-1.dll
libwinpthread-1.dll
libstdc++-6.dll
libwinpthread-1.dll
After trying countless combinations of:
QMAKE_CXXFLAGS += [-static-libgcc | -static-libstdc++ | -static -lstdc++ -lpthread]
and other compiler parameters found in threads similar to this one, what finally worked for me was:
QMAKE_LFLAGS += -static
That is, QMAKE_LFLAGS instead of QMAKE_CXXFLAGS and now my program only relies on a bunch of Windows DLL's. :)
You need to do the below settings in QT Editor
Go to the project tab (on the left) to edit the project's setting.
In the section Run Settings,
Under Working directory click on the checkbox the Run in Terminal.

How configure Qt Creator to compile qupzilla?

Is there any simple way to configure Qt Creator to compile qupzilla in my folder (not in /usr/bin and /usr/lib)?
By default i get "error: ../../bin/libQupZilla.so". If i set the path to my app folder with ldconfig - app is compiled but without plugins. They return errors for example (build/qrc_testplugin.cpp Error 1 or something with locale folder).
OS: Arch Linux 64 bit
QT: Qt5
Also i successfully compile qupzilla-git from AUR with qt5. This means that my problem somewhere in incorrect settings or paths...
Qupzilla: http://www.qupzilla.com/
Solution:
1) Add path to programm "path_to_app/bin" to ldconfig (/etc/ld.so.conf)
2) Check off in Projects "Shadow build" checkbox.
3) Change qmake to qmake-qt5. If I understand correctly, it is not necessary to do. Since in Arch Linux qmake and qmake-qt5 same.
4) In build environment add
KDE true
USE_WEBGL true
If you have libQupZilla (or any library) somewhere else than system library directories, easiest is to edit the .pro file, add line like:
LIBS += -L$(PWD)/..relative-path-to-library-location../
...or use absolute path to the library if you want. You probably already have -lQupZilla there, so no need to add that the 2nd time.
In general, with problems like this in Qt Creator, look at the Compile Output tab (at the bottom of the screen). Find the link command (note: if project uses cmake instead of qmake, you may need to add some switches or something for that to make the command visible), which is the one with all the -L/path and -lfoobar switches, and -o programname outputting the final target. Then look earlier to see in what directory it is being run in. Then look if everything matches, and possibly try to copy-paste and run the command from command line yourself, in the same directory where it is run when building under Qt Creator.

How to compile a Qt program without installing sdk

Can someone tell me if it's possible to compile a project that works with Qt but without installing the entire sdk ? I mean, something like recompile Qt source code and link the libraries or something like this.
I know my problem is weird but I work in special conditions : I am on a linux machine and I have to work on a windows project therefore I use a distant server on windows to compile but I can't install anything on this serveur. I need an idea to have a fully portable folder with Qt who can compile without installing anything.
I hope I was clear in my explications.
Thank you for your help.
I has combined comments in answer.
You need to install compiler (e.g minGW) and Qt Library (as needed version).
You should add into environment variable 'PATH' your path to qmake and compiler.
Start terminal and move to directory with your source code of Qt project.
Run qmake and then exec make (e.g. It, for minGW, is mingw32-make).
For your case, you may choosen 2 way:
Build static Qt Library from source code and use static linking with your project.
Install Qt Library and copy libraries near your project with dynamic linking (recomended).

Qt app finds libraries when launched from QtCreator, but not from command line

I need to ship a product with shared libraries (Ubuntu) in a folder I've created ('shared') within the project directory--i.e., shared libraries that are not in /usr/lib, /usr/local/lib, etc. To this end I've done this in the .pro file, i.e.
LIBS += -Lshared/gsl -lgsl -lgsl_cblas
NB the executable is in the same directory asy the 'shared' folder. Everything works when I launch the program in debug mode from QtCreator. In addition the program fails to launch if I remove or rename the libs in 'shared', and also I've verified that the app is not finding these libraries anywhere else. But when I launch from the command line, I get
error while loading shared libraries: libgslcblas.so.0: cannot open
shared object file: No such file or directory
What's going on?
EDIT: The solution is a variation on lionbest's below, as developed in the comments. For some reason, it turns out that on my platform qmake/QMAKE_FLAGS only allows a specific format for linker options, and not the one you find googling around for other instances where people have worked with QMAKE_FLAGS. Namely,
QMAKE_FLAGS += "-Wl,-rpath,\'\$$ORIGIN/shared/gsl\'"
QMAKE_LFLAGS_RPATH=
Specifically, the problem was that the parser (or linker) would not accept -rpath=..., despite the fact that this seems to work for everyone else. Ubuntu 12.04, gcc 4.6.3, Qt 4.8.0, QtCreator 2.4.1 "based on Qt 4.7.4". Hope this experience can save someone else the same frustration.
Start a program with environmental variable LD_LIBRARY_PATH=shared/gsl or add a RPATH to linker settings:
LIBS += -Wl,-rpath=shared/gsl
If you want to make shortcut for your application, most distribution (based on Gnome, KDE, LXDE and XFCE) use a .desktop file. QtCreator probably generated one for you. You need to edit it or generate it, and put to $HOME/.local/applications or /usr/share/applications/ during installation. In desktop file you could add envirometal varible and starting directory as follow:
Exec=/usr/bin/env LD_LIBRARY_PATH=/<path_to_libs>/ /<path>/app -extra_options
If you need to run your application in specific directory add line:
Path=/<path_to_your_application_working_dir>
You can use ${} inside path.

How to Link Imagemagick library to Qt(windows)

I have developed an application with mac and for one month now, Im trying to link Qt with ImageMagick on windows.
I just cant find the files and the version of Imagemagick library that need to be linked to Qt in order to make my application work on windows.
I have tried most of the libraries from here
Thats the only thing I added to the .pro file while I was developing on a mac
INCLUDEPATH += . /opt/local/include/ImageMagick
LIBS += -L/opt/local/lib -lMagick++
When I add this to my .pro
INCLUDEPATH += C:/im6/include/ImageMagick
LIBS += C:/im6/lib/libMagickWand.a
LIBS += C:/im6/lib/libMagick++.a
LIBS += C:/im6/lib/libMagickCore.a
C:/im6/lib/libMagick++.a
I get 10.000 + simmilar errors to that:
(Image.o):C:\msys\1.0\home\cristy\ImageMagick-6.6.6-0/Magick++/lib/Image.cpp:4157: undefined reference to `__gxx_personality_sj0'
C:/im6/lib/libMagick++.a(Image.o):C:\msys\1.0\home\cristy\ImageMagick-6.6.6-0/Magick++/lib/Image.cpp:4157: undefined reference to `_Unwind_SjLj_Register'
C:/im6/lib/libMagick++.a(Image.o):C:\msys\1.0\home\cristy\ImageMagick-6.6.6-0/Magick++/lib/Image.cpp:4178: undefined reference to `_Unwind_SjLj_Unregister'
For more errors check this
Has anyone tried to build and deploy an ImageMagick application using qt on windows ?
Which files do I need to link while building and which files while deploying ?
The error message tells me that you
use mingw (with qtcreator). Your
library might not work with this
compiler. You need a mingw version
of the library, probably named
libmagick.a.
LIBS += -L$$quote(c:/Program Files/ImageMagick-6.6.5-Q16/lib) -lmagick
(see the documentation about qmake Project Files
I have found that the minGW tool set is very much treated as a "stepchild" in the Windows world. I know it doesn't help your particular situation, but we had numerous problems with third-party libs while trying to use Qt with minGW. There were always extra steps, or non-existent build instructions that we had to figure out or tweak.
Once we switched to the MSVC version, all of those problems went away. Note that this doesn't mean you have to use Visual Studio (you can still use Qt creator), it just means that the Visual Studio compiler is being used. You can get the compiler for free using the Platform SDK. If this is an option, you might save yourself a lot of pain by switching now. It's unfortunate, but that is just the current status quo, at least as we discovered.
Please go get ImageMagick source package.
I can’t give direct instructions how to work with MinGW of Qt Creator, but basically following. I prefer to use qtvars.bat that comes with binary distributions of Qt to set environment.
Open Windows cmd
Set PATH to have /path/to/mingw/bin and /path/to/qt/bin before other paths
Go to directory where you have extracted ImageMagick source
read README, INSTALL and such to compile the ImageMagick (most likely just ./configure ; mingw32-make, but never be sure)
Edit your .pro file with something like LIBS += -L$$quote(/path/to/imagemagick/lib/dir) -lmagick . The lib may be in bin dir or in lib dir. See hmuelner’s answer for more information.
At this point, the configuration should be ready. Compilation at Qt Creator should work, but you can as well use this cmd windows to compile your program: go to program directory, run “qmake” and “mingw32-make”.
You cannot link against a ImageMagick++ library built with MSVC, as mingw and MSVC DLLs are incompatible for C++ libraries. You can't link a MSVC-built C++ library into a mingw project, nor vice versa. C-only libraries work fine. Also, according to this fortum thread, using builds against old mingw-versions with current mingw versions doesn't work as the exception handling changed (as you get more errors than that, I wouldn't expect that to be the only problem though). If there is no binary package for your mingw version (and I don't see any on the imagemagick website), your only option is to use a source package, as Smar suggests.
Another option of course is to install Visual Studio, download Qt for MSVC and build your project with MSVC.