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/*!
    \page windows.html
    \title Qt for Windows
    \brief Platform support for Windows.
    \ingroup supportedplatform

    Qt's support for different Windows platforms is extensive and mature.

    Before you get started,
    ensure that your development environment fulfills
    the \l{Qt for Windows - Requirements}{requirements}.

    To download and install Qt for Windows, follow the instructions on the
    \l{Getting Started with Qt} page.

    \target windows-supported-configurations
    \section1 Supported Configurations

    The following configurations are supported.

    \include supported-platforms.qdocinc windows

    \section1 Deployment and Other Issues

    The pages below covers specific issues and recommendations for creating
    Windows applications.

    \list
    \li \l{Qt for Windows - Deployment}
    \li \l{Qt for Windows - Specific Issues}
    \endlist

    \section1 Where to Go from Here

    We invite you to explore the rest of Qt. We prepared overviews which help
    you decide which APIs to use and our examples demonstrate how to use our
    API.

    \list
    \li \l{Qt Overviews} - list of topics about application development
    \li \l{Qt Examples and Tutorials}{Examples and Tutorials} - code samples and tutorials
    \li \l{Qt Reference Pages} - a listing of C++ and QML APIs
    \li \l{ActiveX in Qt}
    \endlist

    Qt's vibrant and active community site, \l{http://qt.io} houses
    a wiki, a forum, and additional learning guides and presentations.

    \section2 Visual Studio Tools

    \l {Qt VS Tools} enables programmers to create, build, debug, and run
    Qt applications from Microsoft Visual Studio. It contains project wizards,
    Qt project import and export support, integrated Qt resource manager,
    and automated build setup for the Qt Meta-Object Compiler, User Interface
    Compiler, and Resource Compiler.

*/

/*!
    \page windows-requirements.html
    \title Qt for Windows - Requirements
    \brief Requirements of the Windows environment.

    This page describes the required libraries and environment for
    \l{Qt for Windows}.

    \section1 Libraries

    The following third-party libraries may be used when running Qt 5
    applications on Windows.

    \list
        \li \l{OpenSSL Toolkit}: Qt can make use of OpenSSL to support Secure Socket Layer
           (SSL) communication.

        \li \l{ICU}: Qt 5 can make use of the ICU library for enhanced UNICODE and Globalization
           support (see QTextCodec, QCollator::setNumericMode()).

           At compile time, the \e include and \e lib folders of the ICU installation must
           be appended to the \c INCLUDE and \c LIB environment variables. At run-time, the ICU DLLs
           need to be found by copying the DLLs to the
           application folder or by adding the \e bin folder of the ICU
           installation to the \c PATH environment variable.

        \li \l{ANGLE}: This library converts OpenGL ES 2.0 API calls to DirectX 11 or DirectX 9
           calls (depending on availability), removing the need to install graphics drivers on
           the target machines.
     \endlist

    \section2 SSL

    Support for Secure Sockets Layer (SSL) communication is provided by the \l {OpenSSL Toolkit},
    which must be obtained separately. Download the latest version of the toolkit that is
    supported by Qt.

    Qt can be configured to use OpenSSL in three ways:
    \list
        \li Qt Network loads OpenSSL libraries (DDLs) when first needed, at runtime. If not found,
            the application continues to run, but fails to handle SSL communication.

            All official Qt binary builds use this configuration.

            The OpenSSL libraries are looked up first in the directory of the executable, then in
            the Windows System directory (usually \c{C:\Windows\system32}), and finally in all
            directories listed in the \c PATH environment variable.

        \li Qt Network links against the OpenSSL libraries. If they cannot be found at load time,
            the application fails to start.

        \li Qt Network compiles against a static version of the OpenSSL libs, and OpenSSL becomes
            part of the Qt5Network library.
    \endlist


    If you compile Qt yourself, you can configure how Qt uses OpenSSL by setting either the
    \c{-openssl} / \c{-openssl-runtime} or \c{-openssl-linked} configure flags.

    If OpenSSL is not found in the normal compiler include and library directories, you can set
    either the \c OPENSSL_PREFIX, or \c OPENSSL_INCDIR and \c OPENSSL_LIBDIR configure arguments.
    If \c OPENSSL_PREFIX is set, \c OPENSSL_INCDIR defaults to \c OPENSSL_PREFIX/include and
    \c OPENSSL_LIBDIR to \c OPENSSL_PREFIX/lib.

    The actual libraries to link to can be tweaked by setting the \c OPENSSL_LIBS,
    \c OPENSSL_LIBS_DEBUG, and \c OPENSSL_LIBS_RELEASE configure arguments.

    \list
        \li To load OpenSSL at runtime, set the \c {-openssl-runtime} configure argument. Qt will
            try to find \c{openssl/ssl.h} and \c{openssl/opensslv.h} in the default include path of
            the compiler. You can specify an additional include directory by setting
            \c OPENSSL_INCDIR.

            For example:
            \badcode
            configure -openssl-runtime OPENSSL_INCDIR="C:\Program Files\OpenSSL-Win64\include"
            \endcode

        \li To link Qt Network against OpenSSL libraries, set the \c{-openssl-linked}
            configure argument. Use the \c{OPENSSL_PREFIX} variable to let Qt correctly locate
            and build against your OpenSSL installation:

            For example:
            \badcode
            configure -openssl-linked OPENSSL_PREFIX="C:\Program Files\OpenSSL-Win64"
            \endcode

        \li To link Qt Network against a static version of the OpenSSL libs, set the
            \c{-openssl-linked} argument, and set \c{OPENSSL_PREFIX}, or \c{OPENSSL_INCDIR}
            and \c{OPENSSL_LIBDIR}. In addition, you probably need to set the \c{OPENSSL_LIBS},
            \c{OPENSSL_LIBS_DEBUG}, \c{OPENSSL_LIBS_RELEASE} configure arguments to let Qt correctly
            link against your static build of the OpenSSL libraries.

            For example:

            \badcode
            set OPENSSL_DIR=C:\Program Files\OpenSSL-Win64
            configure -openssl-linked OPENSSL_INCDIR="%OPENSSL_DIR%\include" OPENSSL_LIBDIR="%OPENSSL_DIR%\lib\VC\static" OPENSSL_LIBS="-lWs2_32 -lGdi32 -lAdvapi32 -lCrypt32 -lUser32" OPENSSL_LIBS_DEBUG="-llibssl64MDd -llibcrypto64MDd" OPENSSL_LIBS_RELEASE="-llibssl64MD -llibcrypto64MD"
            \endcode
    \endlist

    See \l {Secure Sockets Layer (SSL) Classes} for further instructions on Qt with SSL support.

    \section2 ICU

    From Qt 5.3 and onwards, configure does not link Qt Core against ICU libraries
    anymore by default. This reduces the size of a self-contained
    application package considerably.

    Letting Qt Core utilize the ICU libraries however has following advantages:
    \list
      \li Behavior matches other platforms more closely.
      \li Extended set of text codecs (see \l QTextCodec).
      \li QLocale::toUpper(), QLocale::toLower() always use case conversion rules
      specific to the locale.
      \li QCollator::setNumericMode() does work consistently on all Windows versions.
    \endlist

    To explicitly enable the use of ICU in Qt Core, pass \c -icu to \c configure:

    \badcode
    configure -icu
    \endcode

    \section1 Graphics Drivers

    For \l{Qt Quick} 2 to work, a graphics driver that provides OpenGL 2.1 or
    higher is required. The default driver from Windows is OpenGL 1.1. Qt
    includes a version of the \l{ANGLE} project which is included from the
    Windows Qt installers. ANGLE implements the
    OpenGL ES 2.0 API on top of DirectX 11 or DirectX 9.

    ANGLE requires that the DirectX SDK is installed when building Qt.
    If MSVC is used, the DirectX SDK will be provided by the Windows SDK. In
    this case, you will need at least Windows SDK 10.
    For MinGW builds, you have to install the DirectX SDK provided by Microsoft.

    ANGLE chooses the render backend depending on availability. DirectX 11
    is usually preferable. However, some graphics cards may not fully
    support it. For these cases, the environment variable \c QT_ANGLE_PLATFORM
    (introduced in Qt 5.4) can be used to control the render backend. Possible
    values are \c d3d11, \c d3d9 and \c warp.

    To use a custom version of ANGLE, set the \c ANGLE_DIR environment variable
    to point to the ANGLE source tree before building Qt.

    If you installed additional OpenGL drivers from your hardware vendor, then
    you may want to consider using this version of OpenGL instead of ANGLE. To
    use OpenGL, pass the command line options \c{-opengl desktop} to the
    configure script.

    \badcode
    configure -opengl desktop
    \endcode

    To use an OpenGL ES 2.0 emulator instead of ANGLE, use the configure
    options: \c{-opengl es2 -no-angle}.

    \badcode
    configure -opengl es2 -no-angle
    \endcode

    \section2 Dynamically Loading Graphics Drivers

    In addition to the build time configuration, Qt supports choosing
    and loading the OpenGL implementation at runtime. To use this
    mode, pass \c{-opengl dynamic} to the configure script.

    \badcode
    configure -opengl dynamic
    \endcode

    \note As of Qt 5.5 this is the configuration used by the official, pre-built
    binary packages of Qt. It is strongly recommended to use it also in custom
    builds, especially for Qt binaries that are deployed alongside applications.

    \note Combining \c{-opengl dynamic} with \c{-static} is also possible, but
    be aware that ANGLE will not be statically linked into the applications in
    this case, it will still be built as a shared library.

    This configuration is the most flexible because no dependencies or
    assumptions are hardcoded about the OpenGL implementation during build
    time. It allows robust application deployment. When a given environment
    fails to provide a proper OpenGL 2.0 implementation, it will fall back
    automatically to ANGLE. This fallback will be completely transparent to the
    application, and will allow Qt Quick or other OpenGL code to function by
    translating to Direct3D. Such a fallback could, for example, take place on a
    Windows 7 PC with no additional graphics drivers installed. On other
    machines, where there is sufficient OpenGL support, the normal desktop
    OpenGL drivers will be used. Additionally, pure software-based OpenGL
    implementations may be available as additional fallbacks in the future,
    allowing running Qt Quick applications without a GPU.

    When configured with \c{-opengl dynamic}, neither Qt nor the applications
    built using \c qmake will link to the opengl32 (standard desktop OpenGL) or
    QtANGLE libraries. Instead, the appropriate library is chosen at
    runtime. By default, Qt will determine whether the system's opengl32.dll
    provides OpenGL 2 functions. If these are present, opengl32.dll is used,
    otherwise the ANGLE libraries (libEGL.dll and libGLESv2.dll) will be used.
    In case the ANGLE libraries are missing or initialization fails for some
    reason, an additional fallback is attempted by trying to load
    \c{opengl32sw.dll}. See below for details.

    The loading mechanism can be configured through the \c{QT_OPENGL}
    environment variable and the following application attributes:

    \list
    \li \c Qt::AA_UseDesktopOpenGL Equivalent to setting \c{QT_OPENGL} to \c{desktop}.
    \li \c Qt::AA_UseOpenGLES Equivalent to setting \c{QT_OPENGL} to \c{angle}.
    \li \c Qt::AA_UseSoftwareOpenGL Equivalent to setting \c{QT_OPENGL} to \c{software}.
    \endlist

    When a certain configuration is requested explicitly, no checks are done at
    application startup, that is, the system-provided opengl32.dll will not be
    examined.

    The dynamic loading has a significant impact on applications that contain
    native OpenGL calls: they may fail to link since \c qmake no longer
    automatically adds opengl32.lib or libGLESv2.lib. Instead, applications are
    expected to use the OpenGL functions via the QOpenGLFunctions class. Thus
    the direct dependency on the OpenGL library is removed and all calls will be
    routed during runtime to the implementation chosen by Qt.

    Applications that require a certain OpenGL implementation (for example,
    desktop OpenGL due to relying on features provided by OpenGL 3.0 or higher)
    should set the application attributes \c Qt::AA_UseOpenGLES or \c
    Qt::AA_UseDesktopOpenGL before instantiating QGuiApplication or
    QApplication. When these attributes are set, no other OpenGL implementations
    are considered. Additionally, if they wish to, such applications are free to
    make direct OpenGL function calls by adding opengl32.lib to their .pro
    project files: \e{LIBS += opengl32.lib} (Visual Studio) or \e{LIBS +=
    -lopengl32} (MinGW). The result is, from the application's perspective,
    equivalent to the \c{-opengl desktop} build configuration of Qt.

    \c Qt::AA_UseSoftwareOpenGL is special in the sense that it will try to load
    an OpenGL implementation with a non-standard name. The default name is
    \c{opengl32sw.dll}. This allows shipping a software-only OpenGL
    implementation, for example a build of
    \l{http://www.mesa3d.org/llvmpipe.html}{Mesa with llvmpipe}, under this
    name. If necessary, the filename can be overridden by setting the
    \c{QT_OPENGL_DLL} environment variable.

    It is possible to provide a JSON-format configuration file specifying which
    OpenGL implementation to use depending on the graphics card and driver version.
    The location is given by the environment variable \c{QT_OPENGL_BUGLIST}. Relative
    paths are resolved using \c {QLibraryInfo::SettingsPath} or
    \c {QStandardPaths::ConfigLocation}. The file utilizes the format of the
    driver bug list used in \l{The Chromium Projects}. It consists of a list of
    entries each of which specifies a set of conditions and a list of feature keywords.
    Typically, device id and vendor id are used to match a specific graphics card.
    They can be found in the output of the \c qtdiag or \c dxdiag tool.

    The following feature keywords are relevant for choosing the OpenGL implementation:

    \list
        \li \c disable_desktopgl - Disables OpenGL. This ensures that Qt does not attempt
        to use regular OpenGL (opengl32.dll), and that it starts with ANGLE right
        away. This is useful to prevent bad OpenGL drivers from crashing the application.

        \li \c disable_angle - Disables ANGLE. Ensures that Qt does not attempt to use
        ANGLE (and so Direct3D).

        \li \c disable_d3d11 - Disables the D3D11 rasterizer in ANGLE. Instead, the next
        D3D rendering option is tried first. The default order is: D3D11, D3D9, WARP,
        reference implementation.

        \li \c disable_d3d9 - Disables the D3D9 rasterizer in ANGLE

        \li \c disable_rotation - Forces the application to run in landscape orientation
        always. It applies to OpengGL only and has no effect when using ANGLE or Software
        OpenGL implementations. This is intended for drivers that have issues with rotation.
        This feature keyword was introduced in Qt 5.6.

        \li \c disable_program_cache - Disable storing shader program binaries on
        disk. This feature keyword was introduced in Qt 5.12.
    \endlist

    A sample file looks like:

    \badcode
    {
    "entries": [
    {
      "id": 1,
      "description": "Disable D3D11 on older nVidia drivers",
      "os": {
        "type": "win"
      },
      "vendor_id": "0x10de",
      "device_id": ["0x0DE9"],
      "driver_version": {
        "op": "<=",
        "value": "8.17.12.6973"
      },
      "features": [
        "disable_d3d11"
      ]
    },
    ...
    \endcode

    When \c{QT_OPENGL_BUGLIST} is not specified, a built-in list will be
    used. This typically includes some older, less-capable graphics cards with
    \c disable_desktopgl set, in order to prevent Qt from using their unstable
    desktop OpenGL implementations and instead fall back to ANGLE right away.

    In practice the most common combinations are expected to be the following:

    \list
        \li \c disable_desktopgl - In case the system provides OpenGL 2.0 or newer, but
        the driver is known to be unstable and prone to crash.

        \li \c disable_desktopgl, disable_angle - When no accelerated path is
        desired. This ensures that the only option Qt tries is the sofware rasterizer
        (opengl32sw.dll). Can be useful in virtual machines and applications that are
        deployed on a wide range of old systems.

        \li \c disable_d3d11, disable_d3d9 - When the accelerated D3D options are known to
        be unstable and WARP is desired (when available). Can be useful in virtual machines.
    \endlist

    The supported keys for matching a given card or driver are the following. Note that
    some of these are specific to Qt.

    \list
        \li \c os.type - Operating system: \c win, \c linux, \c macosx, \c android
        \li \c os.version - Kernel version
        \li \c os.release - Specifies a list of operating system releases on Windows:
        \c xp, \c vista, \c 7, \c 8, \c 8.1, \c 10.

        \li \c vendor_id - Vendor from the adapter identifier

        \li \c device_id - List of PCI device IDs.

        \li \c driver_version - Driver version from the adapter identifier

        \li \c driver_description - Matches when the value is a substring of the driver
        description from the adapter identifier

        \li \c gl_vendor - Matches when the value is a substring of the \c GL_VENDOR string
    \endlist

    To disable all blacklisting, set the environment variable \c{QT_NO_OPENGL_BUGLIST} to
    any value. This will skip reading any configuration files, and instead will assume that
    nothing is disabled, regardless of the driver or OS.

    \note While not typically needed, \c{QT_NO_OPENGL_BUGLIST} can become relevant in
    certain virtualized environments, with multiple, possibly virtual, graphics adapters
    present. If the logs from categories like \l{qt.qpa.gl} indicate that the detection of
    the driver and display adapter leads to incorrectly disabling OpenGL, it is then
    recommended to set this environment variable in order to enable the application to run
    normally. This environment variable was introduced in Qt 5.15.

    \section1 Building from Source

    These tools are not needed to run Qt 5 applications, but they are required
    for building Qt 5 from source.

    \list
        \li \l Perl - Install a recent version of perl (for instance
            (\l{https://strawberryperl.com/}{Strawberry Perl}) and add
           the installation location to your \c PATH.
        \li Python - Install Python from the \l{http://www.python.org/download/}{here}
           and add the installation location to your \c PATH.
    \endlist

    ANGLE depends on these extra tools from the \l{GnuWin32 Project}{GnuWin32} and
    \l {http://sourceforge.net/projects/winflexbison/}{Win flex-bison}
    projects, which are provided for your convenience in the \e gnuwin32/bin
    folder:
    \list
        \li \l{http://gnuwin32.sourceforge.net/downlinks/gperf.php}{GPerf}
        \li \l{http://sourceforge.net/projects/winflexbison/files/win_flex_bison-2.5.5.zip/download}{Bison, Flex}
    \endlist

    The \e gnuwin32/bin folder should be added to the \c PATH variable.

    \note If you are building qtbase outside of qt5.git, you will need to
    download \e win_bison and \e win_flex from the link above and rename
    them to \e bison and \e flex.

    For instructions for building the Qt 5 source, read
    the \l{Qt for Windows - Building from Source} page.

    \section1 Compilers

    \section2 Visual Studio

    Qt can be built with Visual Studio 2015 (Update 2), Visual Studio 2017,
    Visual Studio 2019 and Build Tools for Visual Studio 2017 and 2019 (see
    also \l {Supported Platforms}).

    \section2 Intel C++ Compiler (Windows, Altix)

    Qt has been tested successfully with:

    \list
    \li Windows - Intel(R) C++ Compiler for 32-bit applications,
       Version 9.1.040.
    \li Altix - Intel(R) C++ Itanium(R) Compiler for Itanium(R)-based
       applications Version 8.1 Build 20050406 Package ID: l_cc_pc_8.1.030
    \endlist

    \section2 GCC (MinGW-builds)

    The minimum version of MinGW-builds supported is GCC 5.1.0
    (\l{https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Personal%20Builds/mingw-builds/5.1.0/threads-posix/sjlj/x86_64-5.1.0-release-posix-sjlj-rt_v4-rev0.7z/download}{64bit},
     \l{https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win32/Personal%20Builds/mingw-builds/5.1.0/threads-posix/sjlj/i686-5.1.0-release-posix-sjlj-rt_v4-rev0.7z/download}{32bit}),
     available from its \l{https://sourceforge.net/projects/mingw-w64/files}{download page}.

    For more information about the MinGW builds, visit the
    \e{Reference Configuration} section of the
    \l{Supported Platforms#Reference Configurations}{supported platforms}
    page.

    \section2 Clang(clang-cl)

    Qt has been tested successfully with Clang 3.8(llvm svn rev. 256453 and clang
    svn rev. 256453). Visual Studio 2015 Update 1 was used to build clang. Mkspec is
    using the clang-cl tool to build Qt. Clang 3.8 does not support precompiled
    headers.

    \sa {QDoc Dependencies}

    \section2 Building Qt WebEngine

    \l{Qt WebEngine} has additional build requirements which are listed in the
    \l{Qt WebEngine Platform Notes}.

    \section1 QDoc Dependencies
    Since version 5.11, \l {QDoc Manual}{QDoc} uses Clang to parse C++ code.
    If you wish to build QDoc manually, refer to \l {Installing Clang for QDoc}
    for specific build requirements.

*/

/*!
    \page windows-issues.html
    \title Qt for Windows - Specific Issues
    \brief A description of issues with Qt that are specific to Windows.

    This page contains information about \l{Qt for Windows}.

    \section1 Installation location

    Installing Qt into a directory with spaces, for example,
    \e{C:\\Program Files}, may cause linker errors like the following:
    \snippet snippets/code/doc_src_platform-notes.qdoc 2

    Install Qt into a sub-directory without spaces to avoid this problem.

    \section1 Possible GL conflict

    There is a known issue when running Microsoft NetMeeting, Lotus SameTime,
    and other applications that require screen grabbing while direct
    rendering is enabled. Other GL-applications may not work as expected,
    unless direct rendering is disabled.

    \section1 Visual Studio

    The Visual C++ Linker doesn't understand filenames with spaces (for example,
    \e{C:\\Program files\\Qt\\}) so you will have to move it to another place,
    or explicitly set the path yourself.

    \snippet snippets/code/doc_src_compiler-notes.qdoc 0

    If you are experiencing strange problems with using special flags that
    modify the alignment of structure and union members (such as \c{/Zp2})
    then you will need to recompile Qt with the flags set for the
    application as well.

    \section1 Fullscreen OpenGL Based Windows

    When a window is using an OpenGL based surface and is appearing in full
    screen mode, problems can occur with other top-level windows which are
    part of the application. Due to limitations of the Windows DWM,
    compositing is not handled correctly for OpenGL based windows when going
    into full screen mode. As a result, other top-level windows are not placed
    on top of the full screen window when they are made visible. For example,
    menus may not appear correctly, or dialogs fail to show up.

    A window can use an OpenGL based surface either explicitly when
    \l {QWindow::}{setSurfaceType()} is called, or when something that
    requires OpenGL is used inside the window, causing the whole window to be
    OpenGL based. For example, QOpenGLWidget or QQuickWidget can trigger this.
    However, if the surface is contained in a QWindow which is hosted with
    \l {QWidget::}{createWindowContainer()}, or the obsoleted QGLWidget is
    used and it does cover the entire full screen window, then this problem
    does not occur.

    To solve this problem, a QWindowsWindowFunction can be used to enable a
    native Windows flag which will set \c WS_BORDER when showing in full
    screen mode. This can be utilized as follows:

    \code
    QWindowsWindowFunctions::setHasBorderInFullScreen(tlwWindow->windowHandle(), true);
    \endcode

    This will give the full screen window a 1-pixel border, thus enabling the
    other top level windows to appear on top.
*/

/*!
    \page windows-deployment.html
    \title Qt for Windows - Deployment

    This documentation describes deployment process for \l{Qt for
    Windows}{Windows}. We refer to the \l{Plug & Paint Example}{Plug & Paint}
    example application through out the document to demonstrate the deployment
    process.

    \section1 The Windows Deployment Tool
    \target windeployqt
    The Windows deployment tool \c windeployqt is designed to automate the
    process of creating a deployable folder containing the \l{Qt}-related
    dependencies (libraries, QML imports, plugins, and translations) required
    to run the application from that folder.
    It creates a sandbox for \l{Qt for UWP}{Universal Windows Platform (UWP)}
    or an installation tree for Windows desktop applications, which can be
    easily bundled into an installation package.

    The tool can be found in \c{QTDIR/bin/windeployqt}. It needs to be run
    within the build environment in order to function correctly. When using
    Qt Installer, the script \c{QTDIR/bin/qtenv2.bat} should be used to set it up.

    \c windeployqt takes an \c .exe file or a directory that contains an \c .exe
    file as an argument, and scans the executable for dependencies. If a
    directory is passed with the \c{--qmldir} argument, \c windeployqt uses the
    \c qmlimportscanner tool to scan QML files inside the directory for QML import
    dependencies. Identified dependencies are then copied to the executable's
    directory.

    In case Qt was built with the configure switch \c{-relocatable} turned off,
    \c windeployqt replaces the hardcoded local paths in Qt5Core.dll by
    relative ones.

    For Windows desktop applications, the required runtime files for the compiler
    are also copied to the deployable folder by default (unless the option
    \c --no-compiler-runtime is specified). In the case of release builds using
    Microsoft Visual C++, these consist of the Visual C++ Redistributable Packages,
    which are intended for recursive installation by the application's installer on
    the target machine. Otherwise, the shared libraries of the compiler runtime are used.

    The application may require additional 3rd-party libraries (for example,
    database libraries), which are not taken into account by windeployqt.

    Additional arguments are described in the tools' help output:

    \badcode
    Usage: windeployqt [options] [files]
    Qt Deploy Tool 5.14.1

    The simplest way to use windeployqt is to add the bin directory of your Qt
    installation (e.g. <QT_DIR\bin>) to the PATH variable and then run:
      windeployqt <path-to-app-binary>
    If ICU, ANGLE, etc. are not in the bin directory, they need to be in the PATH
    variable. If your application uses Qt Quick, run:
      windeployqt --qmldir <path-to-app-qml-files> <path-to-app-binary>

    Options:
      -?, -h, --help            Displays help on commandline options.
      --help-all                Displays help including Qt specific options.
      -v, --version             Displays version information.
      --dir <directory>         Use directory instead of binary directory.
      --libdir <path>           Copy libraries to path.
      --plugindir <path>        Copy plugins to path.
      --debug                   Assume debug binaries.
      --release                 Assume release binaries.
      --pdb                     Deploy .pdb files (MSVC).
      --force                   Force updating files.
      --dry-run                 Simulation mode. Behave normally, but do not
                                copy/update any files.
      --no-patchqt              Do not patch the Qt5Core library.
      --no-plugins              Skip plugin deployment.
      --no-libraries            Skip library deployment.
      --qmldir <directory>      Scan for QML-imports starting from directory.
      --qmlimport <directory>   Add the given path to the QML module search
                                locations.
      --no-quick-import         Skip deployment of Qt Quick imports.
      --no-translations         Skip deployment of translations.
      --no-system-d3d-compiler  Skip deployment of the system D3D compiler.
      --compiler-runtime        Deploy compiler runtime (Desktop only).
      --no-virtualkeyboard      Disable deployment of the Virtual Keyboard.
      --no-compiler-runtime     Do not deploy compiler runtime (Desktop only).
      --webkit2                 Deployment of WebKit2 (web process).
      --no-webkit2              Skip deployment of WebKit2.
      --json                    Print to stdout in JSON format.
      --angle                   Force deployment of ANGLE.
      --no-angle                Disable deployment of ANGLE.
      --no-opengl-sw            Do not deploy the software rasterizer library.
      --list <option>           Print only the names of the files copied.
                                Available options:
                                 source:   absolute path of the source files
                                 target:   absolute path of the target files
                                 relative: paths of the target files, relative
                                           to the target directory
                                 mapping:  outputs the source and the relative
                                           target, suitable for use within an
                                           Appx mapping file
      --verbose <level>         Verbose level (0-2).

    Qt libraries can be added by passing their name (-xml) or removed by passing
    the name prepended by --no- (--no-xml). Available libraries:
    bluetooth concurrent core declarative designer designercomponents enginio
    gamepad gui qthelp multimedia multimediawidgets multimediaquick network nfc
    opengl positioning printsupport qml qmltooling quick quickparticles quickwidgets
    script scripttools sensors serialport sql svg test webkit webkitwidgets
    websockets widgets winextras xml xmlpatterns webenginecore webengine
    webenginewidgets 3dcore 3drenderer 3dquick 3dquickrenderer 3dinput 3danimation
    3dextras geoservices webchannel texttospeech serialbus webview

    Arguments:
      [files]                   Binaries or directory containing the binary.
\endcode

    \section1 Static Linking

    To build static applications, build Qt statically by configuring Qt with
    \c -static:

    \snippet snippets/code/doc_src_deployment.qdoc 11

    If you later need to reconfigure and rebuild Qt from the
    same location, ensure that all traces of the previous configuration are
    removed by entering the build directory and running \c{nmake distclean} or
    \c{mingw32-make distclean} before running \c configure again.

    \section2 Linking the Application to the Static Version of Qt

    As an example, this section will build the \l{tools/plugandpaint/app}{Plug & Paint}
    example statically.

    Once Qt finishes building, build the \l{tools/plugandpaint/app}{Plug & Paint}
    application. First we must go into the directory that contains the
    application:

    \snippet snippets/code/doc_src_deployment.qdoc 13

    Run \c qmake to create a new makefile for the
    application, and perform a clean build to create the statically linked
    executable:

    \snippet snippets/code/doc_src_deployment.qdoc 14

    You probably want to link against the release libraries, and you can specify
    this when invoking \c qmake. Now, provided that everything compiled and
    linked without any errors, we should have a \c plugandpaint.exe file that is
    ready for deployment. To check that the application has the required
    libraries, copy the executable to a machine that does not have Qt or any Qt
    applications installed, and run it on that machine.

    Remember that if your application depends on compiler specific
    libraries, these must still be redistributed along with your
    application. You can check which libraries your application is
    linking against by using the \c depends tool. For more
    information, read the \l {Application Dependencies} section.

    Since we cannot deploy plugins using the static linking
    approach, the application we have prepared is incomplete. It will
    run, but the functionality will be disabled due to the missing
    plugins. To deploy plugin-based applications we should use the
    shared library approach.

    \section1 Shared Libraries

    We have two challenges when deploying the \l
    {tools/plugandpaint/app}{Plug & Paint} application using the shared
    libraries approach: The Qt runtime has to be correctly
    redistributed along with the application executable, and the
    plugins have to be installed in the correct location on the target
    system so that the application can find them.

    \section2 Building Qt as a Shared Library

    For this example, we assume that Qt is installed as a shared library,
    which is the default when installing Qt, in the \e{C:\\path\\to\\Qt}
    directory.

    \section2 Linking the Application to Qt as a Shared Library

    After ensuring that Qt is built as a shared library, we can build
    the \l {tools/plugandpaint/app}{Plug & Paint} application. First, we
    must go into the directory that contains the application:

    \snippet snippets/code/doc_src_deployment.qdoc 15

    Now run \c qmake to create a new makefile for the application, and
    do a clean build to create the dynamically linked executable:

    \snippet snippets/code/doc_src_deployment.qdoc 16

    This builds the core application, the following will build the
    plugins:

    \snippet snippets/code/doc_src_deployment.qdoc 17

    If everything compiled and linked without any errors, we will get
    a \c plugandpaint.exe executable and the \c pnp_basictools.dll and
    \c pnp_extrafilters.dll plugin files.

    \section2 Creating the Application Package

    To deploy the application, we must make sure that we copy the
    relevant Qt DLLs (corresponding to the Qt modules used in
    the application) and the Windows platform plugin, \c {qwindows.dll},
    as well as the executable to the same directory tree in the \c release
    subdirectory.

    In contrast to user plugins, Qt plugins must be put into subdirectories
    matching the plugin type. The correct location for the platform plugin
    is a subdirectory named \c {platforms}. \l{Qt Plugins} section has
    additional information about plugins and how Qt searches for them.

    If dynamic OpenGL is used, you additionally need to include the
    libraries required for \l{ANGLE} and software rendering. For \l{ANGLE},
    both \c libEGL.dll and \c libGLESv2.dll from Qt's \c lib directory are
    required as well as the HLSL compiler from DirectX. The HLSL compiler
    library, d3dcompiler_XX.dll, where XX is the version number that ANGLE
    (libGLESv2) was linked against.

    If Qt was configured to link against ICU or OpenSSL, the respective DLL's
    need to be added to the \c release folder, too.

    \note \l{Qt WebEngine} applications have additional requirements that are
    listed in \l{Deploying Qt WebEngine Applications}.

    Remember that if your application depends on compiler specific
    libraries, these must be redistributed along with your
    application. You can check which libraries your application is
    linking against by using the \c depends tool. For more
    information, see the \l {Application Dependencies} section.

    We'll cover the plugins shortly, but first we'll check that the
    application will work in a deployed environment: Either copy the
    executable and the Qt DLLs to a machine that doesn't have Qt
    or any Qt applications installed, or if you want to test on the
    build machine, ensure that the machine doesn't have Qt in its
    environment.

    If the application starts without any problems, then we have
    successfully made a dynamically linked version of the \l
    {tools/plugandpaint/app}{Plug & Paint} application. But the
    application's functionality will still be missing since we have
    not yet deployed the associated plugins.

    Plugins work differently to normal DLLs, so we can't just
    copy them into the same directory as our application's executable
    as we did with the Qt DLLs.  When looking for plugins, the
    application searches in a \c plugins subdirectory inside the
    directory of the application executable.

    So to make the plugins available to our application, we have to
    create the \c plugins subdirectory and copy over the relevant DLLs:

    \snippet snippets/code/doc_src_deployment.qdoc 18

    An archive distributing all the Qt DLLs and application
    specific plugins required to run the \l {tools/plugandpaint/app}{Plug
    & Paint} application, would have to include the following files:

    \table 100%
    \header
        \li Component \li {2, 1} File Name
    \row
        \li The executable
        \li {2, 1} \c plugandpaint.exe
    \row
        \li The Basic Tools plugin
        \li {2, 1} \c plugins\pnp_basictools.dll
    \row
        \li The ExtraFilters plugin
        \li {2, 1} \c plugins\pnp_extrafilters.dll
    \row
        \li The Qt Windows platform plugin
        \li {2, 1} \c platforms\qwindows.dll
    \row
        \li The Qt Windows Vista style plugin
        \li {2, 1} \c styles\qwindowsvistastyle.dll
    \row
        \li The Qt Core module
        \li {2, 1} \c Qt5Core.dll
    \row
        \li The Qt GUI module
        \li {2, 1} \c Qt5Gui.dll
    \row
        \li The Qt Widgets module
        \li {2, 1} \c Qt5Widgets.dll
    \endtable

    Other plugins might be required depending on the features the application uses
    (\c iconengines, \c imageformats).

    In addition, the archive must contain the following compiler
    specific libraries (assuming Visual Studio 14.0 (2015) or 15.0 (2017) or 16.0 (2019)):

    \table 100%
    \header
        \li Component \li {2, 1} File Name
    \row
        \li The C run-time
        \li {2, 1} \c vccorlib140.dll, \c vcruntime140.dll
    \row
        \li The C++ run-time
        \li {2, 1} \c msvcp140.dll
    \endtable

    If dynamic OpenGL was used, then the archive must additionally contain:

    \table 100%
    \header
        \li Component \li {2, 1} File Name
    \row
        \li ANGLE libraries
        \li {2, 1} libEGL.dll, libGLESv2.dll
    \row
        \li HLSL compiler library for ANGLE
        \li {2, 1} d3dcompiler_XX.dll
    \row
        \li OpenGL Software renderer library
        \li opengl32sw.dll
    \endtable

    Finally, if Qt was configured to use ICU, the archive must contain:

    \table 100%
    \header
        \li{3,1} File Name
    \row
        \li icudtXX.dll
        \li icuinXX.dll
        \li icuucXX.dll
    \endtable

    To verify that the application now can be successfully deployed,
    you can extract this archive on a machine without Qt and without
    any compiler installed, and try to run it.

    An alternative to putting the plugins in the plugins subdirectory
    is to add a custom search path when you start your application
    using QCoreApplication::addLibraryPath() or
    QCoreApplication::setLibraryPaths().

    \snippet snippets/code/doc_src_deployment.cpp 19

    One benefit of using plugins is that they can easily be made
    available to a whole family of applications.

    It's often most convenient to add the path in the application's \c
    main() function, right after the QApplication object is
    created. Once the path is added, the application will search it
    for plugins, in addition to looking in the \c plugins subdirectory
    in the application's own directory. Any number of additional paths
    can be added.

    \section2 Manifest files

    When deploying an application compiled with Visual Studio, there are some
    additional steps to be taken.

    First, we need to copy the manifest file created when linking the
    application. This manifest file contains information about the
    application's dependencies on side-by-side assemblies, such as the runtime
    libraries.

    The manifest file needs to be copied into the \b same folder as the
    application executable. You do not need to copy the manifest files for
    shared libraries (DLLs), since they are not used.

    If the shared library has dependencies that are different from the
    application using it, the manifest file needs to be embedded into the DLL
    binary. Since Qt 4.1.3, the following \c CONFIG options are available for
    embedding manifests:

    \snippet snippets/code/doc_src_deployment.qdoc 20

    Both options are enabled by default. To remove \c{embed_manifest_exe}, add

    \snippet snippets/code/doc_src_deployment.pro 21

    to your .pro file.

    You can find more information about manifest files and side-by-side
    assemblies at the
    \l {http://msdn.microsoft.com/en-us/library/aa376307.aspx}{MSDN website}.

    The correct way to include the runtime libraries with your application
    is to ensure that they are installed on the end-user's system.

    To install the runtime libraries on the end-user's system, you need to
    include the appropriate Visual C++ Redistributable Package (VCRedist)
    executable with your application and ensure that it is executed when the
    user installs your application.

    They are named \c vcredist_x64.exe (64-bit) or
    \c vcredist_x86.exe (32-bit) and can be found in the folder
    \c{<Visual Studio install path>/VC/redist/<language-code>}.

    Alternatively, they can be downloaded from the web, for example
    \l{https://www.microsoft.com/download/details.aspx?id=48145}
    {vcredist_x64.exe for Visual Studio 2015}.

    \note The application you ship must be compiled with exactly the same
    compiler version against the same C runtime version. This prevents
    deploying errors caused by different versions of the C runtime libraries.

    \section1 Application Dependencies

    \section2 Additional Libraries

    Depending on configuration, compiler specific libraries must be
    redistributed along with your application.

    For example, if Qt is built using \l{ANGLE}, its shared libraries
    and the HLSL compiler from DirectX to be shipped as well.

    You can check which
    libraries your application is linking against by using the
    \l{Dependency Walker} tool. All you need to do is to run it like
    this:

    \snippet snippets/code/doc_src_deployment.qdoc 24

    This will provide a list of the libraries that your application
    depends on and other information.

    \image deployment-windows-depends.png

    When looking at the release build of the Plug & Paint executable
    (\c plugandpaint.exe) with the \c depends tool, the tool lists the
    following immediate dependencies to non-system libraries:

    \table 100%
        \header
            \li Qt
            \li VC++ 14.0 (2015)
            \li MinGW
        \row
        \li \list
               \li QT5CORE.DLL - The QtCore runtime
               \li QT5GUI.DLL - The QtGui runtime
               \li QT5WIDGETS.DLL - The QtWidgets runtime
           \endlist
        \li \list
               \li VCCORLIB140.DLL, VCRUNTIME140D.DLL - The C runtime
               \li MSVCP140.DLL - The C++ runtime
           \endlist
        \li \list
               \li LIBWINPTHREAD-1.DLL
               \li LIBGCC_S_DW2-1.DLL
               \li LIBSTDC++-6.DLL
           \endlist
    \endtable

    When looking at the plugin DLLs the exact same dependencies
    are listed.

    From Qt version 5.2 onwards, the officially supported version
    for OpenSSL is 1.0.0 or later. Versions >= 0.9.7 and < 1.0.0 might
    work, but are not guaranteed to.

    \section2 Qt Plugins

    All Qt GUI applications require a plugin that implements the \l {Qt
    Platform Abstraction} (QPA) layer in Qt 5. For Windows, the name of the
    platform plugin is \c {qwindows.dll}. This file must be located within a
    specific subdirectory (by default, \c platforms) under your distribution
    directory. Alternatively, it is possible to adjust the search path Qt
    uses to find its plugins, as described below.

    Your application may also depend on one or more Qt plugins, such
    as the print support plugin, the JPEG image format plugin or a SQL driver
    plugin. Be sure to distribute any Qt plugins that you need with your
    application. Similar to the platform plugin, each type of plugin must
    be located within a specific subdirectory (such as \c printsupport,
    \c imageformats or \c sqldrivers) within your distribution directory.

    As of Qt 5.14, the libraries are relocatable unless Qt was built with
    the configure switch \c{-relocatable} turned off. The search paths for
    Qt plugins are relative to the location of the QtCore library and no
    further steps are required to ensure plugins are found after installing
    the application on the target machine.

    \section2 Ensuring Plugins Are Found when Using Non-Relocatable Builds

    For non-relocatable builds, additional steps must be taken to ensure
    plugins are found after the application has been installed on the target
    machine.

    In this case, the search path for Qt plugins is hard-coded into the QtCore
    library. By default, the plugins subdirectory of the Qt installation is
    the first plugin search path. However, pre-determined paths like the
    default one have certain disadvantages. For example, they may not
    exist on the target machine. For that reason, you need to examine various
    alternatives to make sure that the Qt plugins are found:

    \list

    \li \l{qt-conf.html}{Using \c qt.conf}. This approach is the recommended
    if you have executables in different places sharing the same plugins.

    \li Using QApplication::addLibraryPath() or
    QApplication::setLibraryPaths(). This approach is recommended if you only
    have one executable that will use the plugin.

    \li Using a third party installation utility to change the
    hard-coded paths in the QtCore library.

    \endlist

    If you add a custom path using QApplication::addLibraryPath it could
    look like this:

    \snippet snippets/code/doc_src_deployment.qdoc 54

    Then QCoreApplication::libraryPaths() would return something like this:

    \list
    \li \c{C:/customPath/plugins}
    \li \c{C:/Qt/%VERSION%/plugins}
    \li \c{E:/myApplication/directory}
    \endlist

    The executable will look for the plugins in these directories and
    the same order as the QStringList returned by QCoreApplication::libraryPaths().
    The newly added path is prepended to the QCoreApplication::libraryPaths() which
    means that it will be searched through first. However, if you use
    QCoreApplication::setLibraryPaths(), you will be able to determine which paths
    and in which order they will be searched.

    The \l{How to Create Qt Plugins} document outlines the issues you
    need to pay attention to when building and deploying plugins for
    Qt applications.

*/

/*!
    \page windows-building.html
    \title Qt for Windows - Building from Source
    \brief Configuring and building Qt for Windows.

    This page describes the process of configuring and building
    \l{Qt for Windows}. Before building, there are some requirements that are
    given in more detail in the \l{Qt for Windows - Requirements} document.

    You can download the Qt 5 sources from the \l{Downloads} page. For
    more information, visit the \l{Getting Started with Qt} page.


    \section1 Step 1: Install the License File (Commercially Licensed Qt Only)

        If you use Qt with a commercial license, the Qt tools look for a local license file.
        If you are using a binary installer or the commercial Qt Creator, your licenses
        are automatically fetched and stored in your local user profile
        (\c{%USERPROFILE%\AppData\Roaming\Qt\qtlicenses.ini} file).

        If you do not use any binary installer or Qt Creator, you can download
        the respective license file from your \l {Qt Account} Web portal and save
        it to your user profile as \c{%USERPROFILE%\.qt-license}. If you prefer a
        different location or file name, you need to set the \c{QT_LICENSE_FILE}
        environment variable to the respective file path.

    \section1 Step 2: Unpack the Archive

        Uncompress the files into the directory you want Qt installed;
        e.g. \c{C:\Qt\%VERSION%}.

        \note The install path must not contain any spaces or Windows specific
        file system characters.

    \section1 Step 3: Set the Environment Variables

        We recommend creating a desktop link that opens a command
        prompt with the environment set up similar to the
        \uicontrol{Command Prompt} menu entries provided by Visual Studio.
        This is done by creating an application link passing a \c .cmd file setting
        up the environment and the command line option \c /k (remain open)
        to \c cmd.exe.

        Assuming the file is called \c{qt5vars.cmd}
        and the Qt folder is called \c Qt-5 and located under \c C:\Qt:

        \badcode
        REM Set up Microsoft Visual Studio 2017, where <arch> is amd64, x86, etc.
        CALL "C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\VC\Auxiliary\Build\vcvarsall.bat" <arch>
        SET _ROOT=C:\Qt\Qt-5
        SET PATH=%_ROOT%\qtbase\bin;%_ROOT%\gnuwin32\bin;%PATH%
        REM Uncomment the below line when using a git checkout of the source repository
        REM SET PATH=%_ROOT%\qtrepotools\bin;%PATH%
        SET _ROOT=
        \endcode

        A desktop link can then be created by specifying the command
        \c{%SystemRoot%\system32\cmd.exe /E:ON /V:ON  /k C:\Qt\qt5vars.cmd}
        as application and \c{C:\Qt\Qt-5} as working directory.

        \note Setups for MinGW are similar; they differ
        only in that the \c bin folder of the installation should be added to the
        path instead of calling the Visual Studio setup script. For MinGW, please make
        sure that no \c sh.exe can be found in the path, as it affects \c {mingw32-make}.

        Settings required by the additional libraries (see \l{Qt for Windows - Requirements})
        should also go this file below the call to the Windows SDK setup script.

    \section1 Step 4: Build the Qt Library

        The default behavior of configure is to create an in-source build
        of Qt 5. If you want to install Qt 5 to a separate location,
        you need to specify the command line option \c{-prefix <location>}.
        Alternatively, the command line option \c -developer-build creates
        an in-source build for developer usage.

        To configure the Qt library for a debug build for your machine, type
        the following command in the command prompt:

        \badcode
        configure -debug -nomake examples -nomake tests -skip qtwebengine -opensource
        \endcode

        The \l{Qt Configure Options}{Configure Options} page contains more
        information about the configure options.

        To build Qt using \l{jom}, type:

        \badcode
        jom
        \endcode

        If you do not have \l{jom} installed, type:

        \badcode
        nmake
        \endcode

        For MinGW, type:

        \badcode
        mingw32-make
        \endcode

        If an installation prefix was given, type
        \c{jom install}, \c{nmake install} or \c{mingw32-make install}.

        \note If you later need to reconfigure and rebuild Qt from the
        same location, ensure that all traces of the previous configuration are
        removed by entering the build directory and typing \c{nmake distclean}
        before running \c configure again.

    \section1 Parallel Builds

        \l{jom} is a replacement for \c nmake which makes use of all CPU cores
        and thus speeds up building.

    \section1 Step 5: Build the Qt Documentation

        For the Qt reference documentation to be available in \l {Qt Assistant},
        you must build it separately:

        \badcode
        nmake docs
        \endcode

        This will build the documentation in the build folder. If you have
        installed Qt in a separate location, you will also need to install
        the documentation:

        \badcode
        nmake install_docs
        \endcode
*/
