Qt application depends on dll's (which it doesn't need?) - c++

I am compiling a Qt Webkit application and I understand webkitwidgets depends on a fair few dll's, however does every Webkit application required all these 20+ dll's to be shipped? Or am I doing something wrong here. This is every DLL needed to run my program.
CFF Explorer only shows these 10 DLLs:
The app comes to a hefty ~150mb so any way to reduce this? I wanted to compile statically however you cannot use webkit that way.

Open your Qt command promp.
mkdir installer
cd installer
Copy your generated exe file to this folder. And run:
windeployqt .
This command will copy all files you need. Use DependencyWalker for more info.
WARNING: some dlls are copied to be used in other OS version, so dont remove it, specially if you want that your app be compatible from Windows XP to Windows 10.

Related

Qt C++ Missing DLLs

I created a simple notepad file using Qt.
The program does run when in Qt creator.
However, when I navigate to the debug folder, the created executable file does not run without DLLs.
I've read online that this is can happen and all that is required is that the respective DLLs be copied to the location of the exe file. However... the error messages identify DLLs that my machine does not have.
I get and error message for the following DLL files.
Qt5Cored.dll, Qt5Widgetsd.dll, QtPrintSupportd.dll
I do not have the DLLs above. I do however have the dll files below. Which do not have the added 'd' before the extension.
Qt5Core.dll, Qt5Widgets.dll, QtPrintSupport.dll
Any help provided would be much appreciated.
Thank you in advance!
First i can't think of any reason you would want to copy (preparing for an installer) the dependencies for the debug build of your application, the debug is not a build that you want to deploy, use the release build for deployment.
Now, that being said, you definitely have the dll's, otherwise your debug build won't run from Qt Creator, you are just not looking in the right path for those dlls.
The path where you find the dll is something like: C:\Qt\5.12.3\msvc2017_64\bin
notice that there can be many Qt versions installed and for different targets (example android), so the right way to find the dlls is: QT_INSTALL_PATH / QT_VERSION / COMPILER_VERSION _ARCHITECTURE / bin, so the sample path i provided is Qt version 5.12.3 build with Visual Studio 2017's compiler and it is a 64 bit build. In that path you will find the right dlls: Qt5Core.dll (the release build), Qt5Cored.dll (debug) and so on for all the Qt modules.
Side note: you most likely looked into the folder where Qt Creator .exe is located, there you will find only the Qt dlls that are needed for Qt Creator to work, you are not supposed to use those dlls to deploy your application (those might be built with a different compiler than what you are using and even cause crashes for your application, because of incompatible abi)

Qt Application (release) crashes when DLLs are added to its directory [duplicate]

I've written a couple of applications in QML (part of Qt 5). In a question that I've made before (https://softwareengineering.stackexchange.com/questions/213698/deploying-qt-based-app-on-mac-os-x), I found the solution for deploying my app on OS X (using the macdeployqt tool).
Deploying Qt4 apps on Windows was easy:
You compiled it in release mode.
You copied the necessary libraries (DLLs).
You tested and it worked.
Unfortunately, this approach did not work in Qt5 (I even included the platforms folder with the qwindows.dll file and it did not work). After some days of trying, I gave up and compiled a static version of Qt5.
Again, it did not work. The app works on a PC with Qt installed, but it crashes on "clean" PCs. As a side note, Windows 8/8.1 systems don't give a warning or a message notifying me about the app's crash. But in Windows 7 a message notifies me that the application crashed.
I've tried running Dependency Walker (depends.exe) and all libraries in the static build of my application seemed fine.
In Windows 8, I don't get any error. But after profiling the app in depends.exe, I get an access violation originating from QtGui.dll. The exact error is
Second chance exception 0xC0000005 (Access Violation) occurred in "QT5GUI.DLL" at address 0x61C2C000.
Is there something that I am missing (say an extra DLL or config file)?
Application information:
Written and compiled with Qt 5.2.1
Uses Quick/QML.
Uses the network module.
Uses the webkit module.
Uses the bluetooth module.
The QML files are written in Quick 2.2
Starting from Qt 5.2, there is windeployqt tool you can use. Just run it from command line to get help. But basic usage is, give it the .exe file, it will copy Qt dependencies to go with it.
You will want to use --qmldir option to let the tool know where your QML files are, so it can figure out the needed QML dependencies.
Note about testing: to make sure you have everything, test in computer with no Qt SDK, or temporarily rename the Qt directory. Otherwise the application might find missing files from there...
After some hours digging in the Qt Forums, I found out that I need to copy the "qml" folder (normally located in C:/Qt/5.2.1/qml) to the application's root directory. After doing so, both the dynamic and static versions of my application worked on vanilla systems.
Program directory (MinGW 4.8 32-bit, dynamic):
As hyde said, use the windeployqt tool (<qt path>\<version>\bin\windeployqt.exe) to copy the necessary files to your application's folder. After that, copy the required QML components from <qt path>\<version>\qml\ to your application's folder. The resulting folder should look similar to:
platforms (folder)
QtQuick (folder)
QtQuick.2 (folder)
Any other QML components that you need
app.exe
icudt51.dll
icuin51.dll
icuuc51.dll
libgcc_s_dw2-1.dll
libstdc++-6.dll
libwindthread-1.dll
Qt5Core.dll
Qt5Gui.dll
Qt5Qml.dll
Qt5Quick.dll
Qt5Network.dll
Qt5Widgets.dll
Program directory (static)
Compile the application statically, then copy the required QML components from <qt path>\<version>\qml\ to your application's folder. The resulting folder should look similar to:
QtQuick (folder)
QtQuick.2 (folder)
Any other QML components that you need
app.exe
I think the cause for the crash was that the Qt5Gui.dll (dynamic and static) "tried" to load the QtQuick* folders during run time, but could not find them (thus crashing the application during load).

Application failed to start because it could not find or load the QT platform plugin "windows"

I have looked through all of the questions that appear to be related on stack overflow, and none of the solutions seem to help me.
I am building a Qt application with this setup:
Windows 7 Professional x64
Visual Studio 2012
Qt 5.2.0 built with configure -developer-build -debug-and-release -opensource -nomake examples -nomake tests -platform win32-msvc2012 -no-opengl
Project uses QtSingleApplication (qt-solutions)
Application is a 32 bit application
qmake run with the following: -makefile -spec win32-msvc2012
.pri uses QMAKE_CXX += /D_USING_V110_SDK71_
I can build and run my program fine on my development machine (noted above); I can also install and run the package from Program Files directory on dev machine.
When I install and run on a Windows Vista machine (multiple machines)
VC++ redist 2012 11.0.61030.0 installed
VC++ redist 2010 10.0.40219 installed
plus 2005, 2008 versions of redist
(also fails on a clean install of Windows 7)
I get:
Application failed to start because it could not find or load the QT platform plugin "windows"
So I followed the instructions and added a .platforms/ directory, and added qwindows.dll (also added qminimal.dll and qoffscreen.dll); I also added libEGL.dll, libGLESv2.dll (even though I shouldn't need them I don't think)
Once I added qoffscreen.dll I now get the additional message: Available platform plugins are: offscreen
If I run through Dependency Walker I get this error listed:
GetProcAddress(0x76CA0000 [KERNEL32.DLL], "GetCurrentPackageId") called from "MSVCR110.DLL" at address 0x6AC6FDFA and returned NULL. Error: The specified procedure could not be found (127).
and then further down get the:
GetProcAddress(0x745A0000 [UXTHEME.DLL], "BufferedPaintUnInit") called from "COMCTL32.DLL" at address 0x745FFBF8 and returned 0x745AE18C.
This application failed to start because it could not find or load the Qt platform plugin "windows".
Available platform plugins are: offscreen.
Reinstalling the application may fix this problem.
Any ideas how to fix this dll issue?
The error is caused because the program can't find qwindows.dll
qwindows.dll has to be in a folder named platforms so that the path from your executable to the dll is platforms/qwindows.dll
Whereas this wasn't enough in my case. I had also to add following line at the beginning of my main()
QCoreApplication::addLibraryPath("./");
Then everything worked.
The application is able to run on the host system, since the Qt bin path is in the system PATH variable.
There is a standard Qt tool for deployment of Qt applications on Windows windeployqt to be able to run the application on target machines that do not have Qt installed.
That tool takes care about Qt DLL dependencies, makes a copy of platforms\qwindows.dll and also it makes a copy of libraries that you cannot detect with the Dependency Walker, since image plugins and some other DLLs are loaded at runtime.
You do not even need to have your Qt bin folder in your environment PATH. The simplest deployment:
copy built exe binary to a new folder
open cmd console in that folder
call windeployqt using the full path (if it is not in the system PATH) and provide your executable, for example:
c:\Qt\Qt5.2.1\5.2.1\msvc2010_opengl\bin\windeployqt.exe application.exe
As a result you have in that folder all needed Qt DLLs to run the application.
The tool windeployqt has various options. It can also take care about deployment of qml related files.
Of course you can have also issues with MSVC redistributables, but those should be deployed separately and installed once per system.
Only some 3rd party libraries should be copied manually if they are used, for example OpenSSL.
I got this issue and how I solved it:
Used dependency walker(http://www.dependencywalker.com/) to see the exact path of the dlls needed. Try it because both QtCreator and QT framework both have the same dlls and you must pinpoint the exact ones used.
I copied all dlls needed in the same folder as the app.
I have copied the folder platforms from QT framework /plugins and copied it in the same folder as the app. Now the app comtained also plugin/platform/ folder with all its dlls
And the most important step in my case is to create a file named qt.conf in the same folder as the app . This file should contain the path to the plugins. My qt.conf file contains:
[Paths]
Libraries=../lib/qtcreator
Plugins=plugins
Imports=imports
Qml2Imports=qml
I had the same issue "Application failed to start because it could not find or load the QT platform plugin "windows"
I fixed this by copying below files to the app.exe (my app executable) folder,
Qt5Core.dll, Qt5Gui.dll, Qt5Widgets.dll and a "platforms" directory with qminimal.dll, qoffscreen.dll, qwindows.dll.
I hope this will help someone
Note this issue can also be caused if the search path for qwindows.dll that is encoded in your app includes the path where you installed Qt. Consider the following scenario:
I install Qt to c:\Qt\...
I develop an app and deploy it correctly somewhere else.
It runs on any computer properly because it includes qwindows.dll in a subdirectory.
I upgrade my local Qt to a new version.
I try to run my app again.
The result is this error, because the qwindows.dll in c:\Qt\... is found before the one in its local directory and it is incompatible with it. Very annoying.
A solution is to place a file qt.conf in the same directory as your exe file. I don't know how to avoid this. If you used the tool windeployqt.exe to deploy your app, so you have a subdirectory called platforms, then this is sufficient:
[Paths]
Plugins=.
For me, I needed to set QT_QPA_PLATFORM_PLUGIN_PATH to the platforms directory and then it worked.
For what it's worth, this solution was also mentioned on GitHub.
For the people who have this problem in the future - I have a dirty little hack, worked for me. Try at your own risk.
Follow all the steps in Initial deployment (Quick and dirty) [http://wiki.qt.io/Deploy_an_Application_on_Windows]
Close Qt Creator.
Copy the following into C:\Deployment\ The release version of MyApp.exe All the .dll files from
C:\Qt\5.2.1\mingw48_32\bin\ All the folders from
C:\Qt\5.2.1\mingw48_32\plugins\
(If you used QML) All the folders from C:\Qt\5.2.1\mingw48_32\qml\ Rename C:\Qt\ to C:\QtHidden\ (This turns your PC into a clean environment, just like one that doesn't have Qt installed).
Launch C:\Deployment\MyApp.exe.
Now for the hack -
Duplicate your folder for safety
If your file was in /cat/Deployment, go to /cat
Now, delete the Deployment folder while the .exe is still running.
It will tell you that it cannot delete certain files, so say Skip(or skip all)
What you're left with is the list of all the .dll files that your .exe was actually using and could not delete: the list of all the files and only the files that you need to keep.
You can close the .exe file now.
To check whether it is deploying okay, go into the folder where you installed it, say C:/Qt and rename it to C:/NotQt (basically make Qt invisible to the system).
If it works now, it will deploy on other systems more often than not.
Well I solved my issue, although I'm not sure what the difference is:
I copied every dll from my qt directory into both ./ and ./platforms of my application directory.
The application got past the error, but then crashed.
VERSION.dll was causing the crash (noted in dependency walker), so I removed it from both places.
The Application started up, so I systematically removed all unneeded dll's.
This got me back to the same state I had originally.
I then uninstalled my application and re-installed (with only the ./platforms/qwindows.dll file remaining), application works correctly.
So all I can assume is that I had an incorrect version of qwindows.dll in the platforms directory.
I got the same issue:
1. it can run in VS2010;
2. it can run in a folder with files as:
app.exe
\platforms\qwindows.dll
...
but it failed to load qwindows on a clean machine with same OS as the developing one.
Solved simply by move the platform folder to plugins:
app.exe
plugins\platforms\qwindows.dll
plus: qwindows.dll can be renamed as any you like as it is queried by an plugin interafce:
qt_plugin_query_metadata()
It's missing qwindows.dll, which normally should be in platforms, unless you add:
QCoreApplication::addLibraryPath("<yourpath>");
If you don't do this btw, and put your qwindows.dll somewhere else, Qt will search your PATH for the DLL, which may take a LOT of time (10s - several minutes)!
I fixed this by placing qt.conf in my application's exe folder:
[Paths]
Prefix=C:/Qt/Qt5.11.2/5.11.2/msvc2017
Where:
I have installed a custom Qt kit in C:\Qt\Qt5.11.2\5.11.2\msvc2017
qt.conf informs the app where the custom kit via the Prefix property. Note use forward slashes not backslashes (!)
And, optionally, the Qt kit's bin folder is included in my PATH environment variable
Defining Prefix in your qt.conf file allows it to find the qwindows.dll platform plugin when your app starts.
Tried all the above - turned out for me it was simply because I didn't have the main Qt dlls in the apps folder
Qt5Core.dll
Qt5Widgets.dll
etc
You need to add environmental variable QT_QPA_PLATFORM_PLUGIN_PATH to the system which points to the platforms directory in QT plugins. In my case, I was using Anaconda and PySide2. Therefore my directory path was C:\ProgramData\Anaconda3\envs\cv\Lib\site-packages\PySide2\plugins. This fixes the issue for every QT project. Otherwise, you have copy platforms directory to every QT project.

Deploying Qt application using QtMultimedia in release mode

I am developing a Qt 5.0 dekstop application using mingw47. I use QtMultimedia in this application to record and play audio. I have tested it for debug and it works. When I try to build it for release and run the executable file, I can't play the audio file that can normally be played in debug mode. I've added the following dlls before running the executable file:
D3D_Compiler_43.dll,
icudt49.dll,
icuin49.dll,
icuuc49.dll,
libEGL.dll,
libgcc_s_sjlj-1.dll,
libGLESv2.dll,
liblibmpeg2_plugin.dll,
libstdc++-6.dll,
libwinpthread-1.dll,
Qt5Core.dll,
Qt5Gui.dll,
Qt5Multimedia.dll,
Qt5Network.dll,
Qt5Widgets.dll,
Qt5Xml.dll,
plugins/platforms/(all dlls),
plugins/mediaservice/(all dlls),
plugins/playlistformats(all dlls)
What is probably wrong? Or what other dlls am I missing?
UPDATE: Use windeployqt.exe! It works really well.
http://doc.qt.io/qt-5/windows-deployment.html#the-windows-deployment-tool
The simplest way to use windeployqt is to add the bin directory of
your Qt installation (e.g. ) to the PATH variable and then
run:
windeployqt <path-to-app-binary>
While you are running your application in release mode (when it is working, ran from inside Qt Creator), execute depends.exe and point it at the application.
Make note of all the dlls that are referenced from your Qt folder.
Alternate way if you want to take more time with it:
You can figure it out by hand by trying to delete files because Windows won't let you delete a folder or a dll while it is in use. So you could go and make a back up of your Qt installation, and then run you application, make sure it has connected to all the dll's it is going to use, and then try to delete folders and files in your Qt installation. Windows won't let you delete files that are in use by your release.
Also here is how Windows resolves dll's if you wanted to know:
http://msdn.microsoft.com/en-us/library/7d83bc18(v=vs.80).aspx
EDIT: Also, you don't need to make the folder called plugins in your exe directory. It should be something like this:
Qt 4.x:
./myexe.exe
./QtCore.dll
./imageformats/qjpegd4.dll // Note: there isn't a "plugins" folder here
Qt 5.x: (take from here)
The executable ./plugandpaint.exe
The Basic Tools plugin ./plugins/pnp_basictools.dll
The ExtraFilters plugin ./plugins/pnp_extrafilters.dll
The Qt Windows platform plugin ./platforms/qwindows.dll
The Qt Core module ./Qt5Core.dll
The Qt GUI module ./Qt5Gui.dll
The Qt Widgets module ./Qt5Widgets.dll
Also run qDebug() << QApplication::libraryPaths(), and make note of paths that are searched for dlls on your computer.
Hope that helps.
All of the DLL's in your list that have their import libraries linked to the application will be automatically loaded by the OS. If any of them are missing you will get a dialog telling you which DLL it failed to load. The only ones that look like they might be loaded manually by the application are the plugins. Make sure you are telling the QT multimedia system to load the them. Also make sure you check the error codes returned by the multiamedia manager.
Given your recent comment that the audio plays in debug mode but not in release mode is a good indication you have put the plugin DLL's in the wrong place. When you launch your application from Explorer or the command line the plugins directory needs to be in the same directory as the application. Your directory structure should look something like below
c:\stackoverflow\myprogram.exe
c:\stackoverflow\plugins\platforms\(all dlls)
c:\stackoverflow\plugins\mediaservice\(all dlls)
c:\stackoverflow\plugins\playlistformats\(all dlls)
c:\stackoverflow\D3D_Compiler_43.dll
c:\stackoverflow\icudt49.dll
... other dll's here...
c:\stackoverflow\Qt5Network.dll
c:\stackoverflow\Qt5Widgets.dll
c:\stackoverflow\Qt5Xml.dll
I've found the answer. Now my application works. It can play audio file while running the executable file.
Although not listed in depends.exe, we should add the following dlls when using QMediaPlayer:
Qt5MultimediaWidgets
Qt5OpenGL
Here is the reference: https://bugreports.qt-project.org/browse/QTBUG-30172

How to run a Qt application?

I have been using Qt creator to make applications using the Qt libraries. I can run these applications by just clicking the play button, but I want to learn how to make applications run just by double clicking on a .exe. So how can I do this?
If you have built a 'release' version of your program, copy it and the following DLL's from qt\bin to a directory:
QtCore4.dll, QtGui4.dll and mingwm10.dll (if you are compiling with gcc and minGW).
If you are running a 'debug' build, you will need the debug versions of the Qt DLLs. They have the same name but with a 'd' at the end of the name.
There may be other Qt DLLs you will have to copy depending on Qt modules you are using in your program.
You can find out more from this page (Qt docs website) Deploying Qt Applications
I'm assuming you are running windows since you mention an .exe file extension. Look in the debug and/or release subdirectories of your project to find the produced binary. You can double-click on it to run the application. However, there are several DLL's that will be required. So, make sure they are in your PATH or copy them in the same directory. Dependency Walker is useful for finding out what you need.