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Installing QT module to use with QT 5.15

  • Hello I tried installing QT module using following steps
    To use a Qt module, it must be installed in the Qt lib directory.

    First, retrieve the lib directory path executing this command from a terminal:

    qmake -query QT_INSTALL_LIBS
    Cd into that directory and check if a file called Qt5Mqtt.dll is there: if not, you must build/install the module.

    To get the module source code, you can execute this git command:

    git clone git://
    Once you have the source files, cd into the source files directory containing the file and run these commands:

    mingw32-make install

    However after mingw32-make I am getting follwing error

    cd src/ && ( test -e Makefile || C:/Qt_5.15/5.15.2/mingw81_64/bin/qmake.exe -o Makefile C:/Qt_5.15/qtmqtt/src/ ) && mingw32-make -f Makefile
    mingw32-make[1]: Entering directory 'c:/Qt_5.15/qtmqtt/src'
    cd mqtt/ && ( test -e Makefile || c:/Qt_5.15/5.15.2/mingw81_64/bin/qmake.exe -o Makefile C:/Users/zbgtmn/qtmqtt/src/mqtt/ ) && C:/MinGW/bin/mingw32-make -f Makefile
    mingw32-make[2]: Entering directory 'c:/Qt_5.15/qtmqtt/src/mqtt'
    C:/MinGW/bin/mingw32-make -f Makefile.Release
    mingw32-make[3]: Entering directory 'c:/Qt_5.15/qtmqtt/src/mqtt'
    g++ -c -fno-keep-inline-dllexport -O2 -g -std=c++1z -fno-exceptions -Wall -Wextra -Wextra -Wvla -Wdate-time -Wshift-overflow=2 -Wduplicated-cond -Wno-stringop-overflow -DUNICODE -D_UNICODE -DWIN32 -DMINGW_HAS_SECURE_API=1 -DWINVER=0x0601 -D_WIN32_WINNT=0x0601 -DQT_NO_LINKED_LIST -DQT_NO_FOREACH -DQT_NO_JAVA_STYLE_ITERATORS -DQT_NO_NARROWING_CONVERSIONS_IN_CONNECT -DQT_BUILD_MQTT_LIB -DQT_BUILDING_QT -D_CRT_SECURE_NO_WARNINGS -D_USE_MATH_DEFINES -DQT_NO_CAST_TO_ASCII -DQT_ASCII_CAST_WARNINGS -DQT_MOC_COMPAT -DQT_USE_QSTRINGBUILDER -DQT_DEPRECATED_WARNINGS -DQT_DISABLE_DEPRECATED_BEFORE=0x040800 -DQT_DEPRECATED_WARNINGS_SINCE=0x060000 -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_NETWORK_LIB -DQT_CORE_LIB -I. -I../../include -I../../include/QtMqtt -I../../include/QtMqtt/6.1.0 -I../../include/QtMqtt/6.1.0/QtMqtt -Itmp -IC:/Qt_5.15/5.15.2/mingw81_64/include -IC:/Qt_5.15/5.15.2/mingw81_64/include/QtNetwork -IC:/Qt_5.15/5.15.2/mingw81_64/include/QtCore/5.15.2 -IC:/Qt_5.15/5.15.2/mingw81_64/include/QtCore/5.15.2/QtCore -IC:/Qt_5.15/5.15.2/mingw81_64/include/QtCore -I.moc/release -IC:\openssl\include -IC:\Utils\my_sql\mysql-5.7.25-winx64\include -IC:\Utils\postgresql\pgsql\include -IC:/Qt_5.15/5.15.2/mingw81_64/mkspecs/win32-g++ -o .obj/release/qmqttconnection.o qmqttconnection.cpp
    qmqttconnection.cpp: In member function 'void QMqttConnection::finalize_connack()':
    qmqttconnection.cpp:1452:26: error: 'class QList<QMqttTopicName>' has no member named 'resize'; did you mean 'size'?
    qmqttconnection.cpp:1453:26: error: 'class QList<QMqttTopicName>' has no member named 'resize'; did you mean 'size'?
    At global scope:
    cc1plus.exe: warning: unrecognized command line option '-Wno-stringop-overflow'
    Makefile.Release:991: recipe for target '.obj/release/qmqttconnection.o' failed
    mingw32-make[3]: *** [.obj/release/qmqttconnection.o] Error 1
    mingw32-make[3]: Leaving directory 'c:/Qt_5.15/qtmqtt/src/mqtt'
    Makefile:45: recipe for target 'release' failed
    mingw32-make[2]: *** [release] Error 2
    mingw32-make[2]: Leaving directory 'c:/Qt_5.15/qtmqtt/src/mqtt'
    Makefile:49: recipe for target 'sub-mqtt-make_first' failed
    mingw32-make[1]: *** [sub-mqtt-make_first] Error 2
    mingw32-make[1]: Leaving directory 'c:/Qt_5.15/qtmqtt/src'
    Makefile:51: recipe for target 'sub-src-make_first' failed
    mingw32-make: *** [sub-src-make_first] Error 2

    Any help is appreciated. I want to use MQTT with QT 5.15

  • Lifetime Qt Champion

    The dev branch can not be compiled with Qt5 - make sure to use the correct Qt5 branch (e.g. 5.15)

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