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Cannot mix incompatible Qt library

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  • JKSHJ JKSH

    @Tamfub said in Cannot mix incompatible Qt library:

    How do I rebuild the DLLs?

    See https://doc.qt.io/qt-5/sql-driver.html#how-to-build-the-qmysql-plugin-on-windows

    Should I remove them from my Qt 5.15 folder

    Yes, remove everything that you copied. They are incompatible with Qt 5.15.1, as mentioned in your original error message.

    add those in the 5.12.3 folder via the "Add libraries..." tool?

    No, you cannot add DLLs from Qt 5.12.3 into your Qt 5.15.1 project.

    T Offline
    T Offline
    Tamfub
    wrote on last edited by
    #13

    @JKSH
    I've read what's written here. This is my MySql conf folder:
    27d453bb-f335-46c1-ba47-c27cc0a2c84d-image.png
    The files

    • ./include/mysql.h
    • ./bin/libmysql.dll
    • /bin/libmysql.lib

    are present.

    As indicated in the link, I opened a terminal in Windows, in C:\Qt\5.15.1\Src\qtbase and typed
    qmake -- MYSQL_INCDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\include" MYSQL_LIBDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\lib"

    But I got this:
    0d2717b3-8dd4-4033-bb23-42fa49381aa9-image.png

    Instead, this worked:
    9f0342e3-864e-4e41-8f08-777c77418973-image.png

    C:/Qt/5.15.1/mingw81_64/lib is the value of my PATH env variable, and Qt Creator is running in the background. What am I missing/getting wrong?

    JKSHJ 1 Reply Last reply
    1
    • T Tamfub

      @JKSH
      I've read what's written here. This is my MySql conf folder:
      27d453bb-f335-46c1-ba47-c27cc0a2c84d-image.png
      The files

      • ./include/mysql.h
      • ./bin/libmysql.dll
      • /bin/libmysql.lib

      are present.

      As indicated in the link, I opened a terminal in Windows, in C:\Qt\5.15.1\Src\qtbase and typed
      qmake -- MYSQL_INCDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\include" MYSQL_LIBDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\lib"

      But I got this:
      0d2717b3-8dd4-4033-bb23-42fa49381aa9-image.png

      Instead, this worked:
      9f0342e3-864e-4e41-8f08-777c77418973-image.png

      C:/Qt/5.15.1/mingw81_64/lib is the value of my PATH env variable, and Qt Creator is running in the background. What am I missing/getting wrong?

      JKSHJ Offline
      JKSHJ Offline
      JKSH
      Moderators
      wrote on last edited by JKSH
      #14

      @Tamfub said in Cannot mix incompatible Qt library:

      I've read what's written here.

      ...

      The files

      • ./include/mysql.h
      • ./bin/libmysql.dll
      • /bin/libmysql.lib

      are present.

      ...

      As indicated in the link, I opened a terminal in Windows, in C:\Qt\5.15.1\Src\qtbase and typed

      qmake -- MYSQL_INCDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\include" MYSQL_LIBDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\lib"

      These are all very good. You are on the right track.

      EDIT: You are in the wrong folder. You should be in qtbase\src\plugins\sqldrivers\, not in qtbase\.

      What am I missing/getting wrong?

      Have a closer look at the error message. It says, "ERROR: Cannot run compiler 'g++'.... Maybe you forgot to setup the environment?"

      That means your compiler, g++.exe, is not found in your terminal's environment.

      Instead, this worked:
      9f0342e3-864e-4e41-8f08-777c77418973-image.png

      C:/Qt/5.15.1/mingw81_64/lib is the value of my PATH env variable,

      This shows that you have successfully added the Qt 5.15.1 DLLs and executables (like qmake.exe) to your environment.

      You must also add your compiler to your environment. When you do that, you should also get a valid output when you type g++ --version into your terminal.

      You can install the MinGW x64 compiler from the Qt online installer. The default folder is C:\Qt\Tools\mingw810_64\bin.

      Qt Creator is running in the background.

      Qt Creator has no effect on your terminal's environment. You can close Qt Creator.

      Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

      T 1 Reply Last reply
      1
      • JKSHJ JKSH

        @Tamfub said in Cannot mix incompatible Qt library:

        I've read what's written here.

        ...

        The files

        • ./include/mysql.h
        • ./bin/libmysql.dll
        • /bin/libmysql.lib

        are present.

        ...

        As indicated in the link, I opened a terminal in Windows, in C:\Qt\5.15.1\Src\qtbase and typed

        qmake -- MYSQL_INCDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\include" MYSQL_LIBDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\lib"

        These are all very good. You are on the right track.

        EDIT: You are in the wrong folder. You should be in qtbase\src\plugins\sqldrivers\, not in qtbase\.

        What am I missing/getting wrong?

        Have a closer look at the error message. It says, "ERROR: Cannot run compiler 'g++'.... Maybe you forgot to setup the environment?"

        That means your compiler, g++.exe, is not found in your terminal's environment.

        Instead, this worked:
        9f0342e3-864e-4e41-8f08-777c77418973-image.png

        C:/Qt/5.15.1/mingw81_64/lib is the value of my PATH env variable,

        This shows that you have successfully added the Qt 5.15.1 DLLs and executables (like qmake.exe) to your environment.

        You must also add your compiler to your environment. When you do that, you should also get a valid output when you type g++ --version into your terminal.

        You can install the MinGW x64 compiler from the Qt online installer. The default folder is C:\Qt\Tools\mingw810_64\bin.

        Qt Creator is running in the background.

        Qt Creator has no effect on your terminal's environment. You can close Qt Creator.

        T Offline
        T Offline
        Tamfub
        wrote on last edited by
        #15

        @JKSH
        Hi, I've managed to make my qmake command run
        568d7381-2012-451d-aa65-24398f737bbd-image.png
        It asked me which edition I would like to use. After that, I got:
        a7202ee2-acf7-4e2a-b636-0619e9336644-image.png
        If I run mingw32-make, will it install Qt from scratch and delete my Qt folder? Instead, if I run nmake sub-mysql, it says that nmake is not recognized. I tried to replace nmake with mingw32-make, but it says
        005afc67-dd30-4cd0-a5eb-f8770c8c26ce-image.png

        JKSHJ 1 Reply Last reply
        0
        • Christian EhrlicherC Offline
          Christian EhrlicherC Offline
          Christian Ehrlicher
          Lifetime Qt Champion
          wrote on last edited by
          #16

          Please follow the documentation (and start over with a clean source dir):
          C:\Qt5\5.13.2\Src\qtbase\src\plugins\sqldrivers>qmake -version

          Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
          Visit the Qt Academy at https://academy.qt.io/catalog

          1 Reply Last reply
          1
          • T Tamfub

            @JKSH
            Hi, I've managed to make my qmake command run
            568d7381-2012-451d-aa65-24398f737bbd-image.png
            It asked me which edition I would like to use. After that, I got:
            a7202ee2-acf7-4e2a-b636-0619e9336644-image.png
            If I run mingw32-make, will it install Qt from scratch and delete my Qt folder? Instead, if I run nmake sub-mysql, it says that nmake is not recognized. I tried to replace nmake with mingw32-make, but it says
            005afc67-dd30-4cd0-a5eb-f8770c8c26ce-image.png

            JKSHJ Offline
            JKSHJ Offline
            JKSH
            Moderators
            wrote on last edited by
            #17

            @Christian-Ehrlicher is right: You are in the wrong folder. You should be in qtbase\src\plugins\sqldrivers

            You should also clean out your source folders before trying again. (Delete all files that were generated by qmake)

            @Tamfub said in Cannot mix incompatible Qt library:

            Instead, if I run nmake sub-mysql, it says that nmake is not recognized.

            nmake is for MSVC, not MinGW.

            Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

            T 1 Reply Last reply
            1
            • JKSHJ JKSH

              @Christian-Ehrlicher is right: You are in the wrong folder. You should be in qtbase\src\plugins\sqldrivers

              You should also clean out your source folders before trying again. (Delete all files that were generated by qmake)

              @Tamfub said in Cannot mix incompatible Qt library:

              Instead, if I run nmake sub-mysql, it says that nmake is not recognized.

              nmake is for MSVC, not MinGW.

              T Offline
              T Offline
              Tamfub
              wrote on last edited by Tamfub
              #18

              @JKSH Ok, got it. Sorry for the silly question, but how do I clean out the source folders? From the terminal with a specific command in a specific folder? From Qt Creator (like this)?
              b45fc8bc-cff4-49ad-9612-690b97a3eb2a-image.png
              Also, I moved to qtbase\src\plugins\sqldrivers and re-typed (w/out cleaning) qmake -- MYSQL_INCDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\include" MYSQL_LIBDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\lib", but the usage for qmake appeared in the output.

              JKSHJ 1 Reply Last reply
              0
              • T Tamfub

                @JKSH Ok, got it. Sorry for the silly question, but how do I clean out the source folders? From the terminal with a specific command in a specific folder? From Qt Creator (like this)?
                b45fc8bc-cff4-49ad-9612-690b97a3eb2a-image.png
                Also, I moved to qtbase\src\plugins\sqldrivers and re-typed (w/out cleaning) qmake -- MYSQL_INCDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\include" MYSQL_LIBDIR="C:\Program Files (x86)\MySQL\MySQL Server 5.5\lib", but the usage for qmake appeared in the output.

                JKSHJ Offline
                JKSHJ Offline
                JKSH
                Moderators
                wrote on last edited by
                #19

                @Tamfub said in Cannot mix incompatible Qt library:

                how do I clean out the source folders? From the terminal with a specific command in a specific folder? From Qt Creator (like this)?

                It depends on how you got your source code.

                If you extracted it from a Zip file, the easiest thing to do is delete the source folders and extract it again.

                You can't use Qt Creator for this.

                the usage for qmake appeared in the output.

                It probably means you made a mistake while typing. Check again carefully after you clean your source folder.

                I just noticed something else: It looks like you are using 64-bit Qt and 64-bit MinGW. Therefore, you must also use the 64-bit MySQL C connector. (Your screenshots show that you've installed 32-bit MySQL)

                Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

                T 1 Reply Last reply
                1
                • JKSHJ JKSH

                  @Tamfub said in Cannot mix incompatible Qt library:

                  how do I clean out the source folders? From the terminal with a specific command in a specific folder? From Qt Creator (like this)?

                  It depends on how you got your source code.

                  If you extracted it from a Zip file, the easiest thing to do is delete the source folders and extract it again.

                  You can't use Qt Creator for this.

                  the usage for qmake appeared in the output.

                  It probably means you made a mistake while typing. Check again carefully after you clean your source folder.

                  I just noticed something else: It looks like you are using 64-bit Qt and 64-bit MinGW. Therefore, you must also use the 64-bit MySQL C connector. (Your screenshots show that you've installed 32-bit MySQL)

                  T Offline
                  T Offline
                  Tamfub
                  wrote on last edited by Tamfub
                  #20

                  @JKSH I made it work now, I have mistaken qtbase\src\plugins with qtbase\plugins. Back to my project now. My .pro file contains:

                  win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysql
                  else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysqld
                  
                  INCLUDEPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include
                  DEPENDPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include
                  

                  That is:
                  0ba17a74-572f-4250-ab40-1617448fbc26-image.png

                  ab1033f1-659e-41b2-b349-00e73c068ae4-image.png

                  c3786cea-672c-4d01-86a6-ff2a48d7910e-image.png

                  The kit is:
                  e4bbfd49-5e30-4b25-b682-fa2a0c156c3b-image.png

                  When I run my project from Qt Creator, it works! I would like to deploy my app, so I go to [build folder]/release, clean its content (except the executable), open a terminal and type
                  windeployqt.exe .

                  I launch the .exe, but the SQL-related part does not work... This is the output of the windeployqt command:

                  C:\Qt\Projects\tutorial\progettoMalnati\sharedtexteditor\build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release\release\progettoMalnati_srv_2.exe 64 bit, release executable
                  Adding Qt5Svg for qsvgicon.dll
                  Direct dependencies: Qt5Core Qt5Gui Qt5Network Qt5Sql Qt5Widgets
                  All dependencies   : Qt5Core Qt5Gui Qt5Network Qt5Sql Qt5Widgets
                  To be deployed     : Qt5Core Qt5Gui Qt5Network Qt5Sql Qt5Svg Qt5Widgets
                  Updating Qt5Core.dll.
                  Updating Qt5Gui.dll.
                  Updating Qt5Network.dll.
                  Updating Qt5Sql.dll.
                  Updating Qt5Svg.dll.
                  Updating Qt5Widgets.dll.
                  Updating libGLESv2.dll.
                  Updating libEGL.dll.
                  Updating D3Dcompiler_47.dll.
                  Updating opengl32sw.dll.
                  Updating libgcc_s_seh-1.dll.
                  Updating libstdc++-6.dll.
                  Updating libwinpthread-1.dll.
                  Creating directory C:/Qt/Projects/tutorial/progettoMalnati/sharedtexteditor/build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release/release/bearer.
                  Updating qgenericbearer.dll.
                  Creating directory C:/Qt/Projects/tutorial/progettoMalnati/sharedtexteditor/build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release/release/iconengines.
                  Updating qsvgicon.dll.
                  Creating directory C:/Qt/Projects/tutorial/progettoMalnati/sharedtexteditor/build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release/release/imageformats.
                  Updating qgif.dll.
                  Updating qicns.dll.
                  Updating qico.dll.
                  Updating qjpeg.dll.
                  Updating qsvg.dll.
                  Updating qtga.dll.
                  Updating qtiff.dll.
                  Updating qwbmp.dll.
                  Updating qwebp.dll.
                  Creating directory C:/Qt/Projects/tutorial/progettoMalnati/sharedtexteditor/build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release/release/platforms.
                  Updating qwindows.dll.
                  Creating directory C:/Qt/Projects/tutorial/progettoMalnati/sharedtexteditor/build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release/release/sqldrivers.
                  Updating qsqlite.dll.
                  Updating qsqlmysql.dll.
                  Updating qsqlodbc.dll.
                  Creating directory C:/Qt/Projects/tutorial/progettoMalnati/sharedtexteditor/build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release/release/styles.
                  Updating qwindowsvistastyle.dll.
                  Creating C:\Qt\Projects\tutorial\progettoMalnati\sharedtexteditor\build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release\release\translations...
                  Creating qt_ar.qm...
                  Creating qt_bg.qm...
                  Creating qt_ca.qm...
                  Creating qt_cs.qm...
                  Creating qt_da.qm...
                  Creating qt_de.qm...
                  Creating qt_en.qm...
                  Creating qt_es.qm...
                  Creating qt_fi.qm...
                  Creating qt_fr.qm...
                  Creating qt_gd.qm...
                  Creating qt_he.qm...
                  Creating qt_hu.qm...
                  Creating qt_it.qm...
                  Creating qt_ja.qm...
                  Creating qt_ko.qm...
                  Creating qt_lv.qm...
                  Creating qt_pl.qm...
                  Creating qt_ru.qm...
                  Creating qt_sk.qm...
                  Creating qt_tr.qm...
                  Creating qt_uk.qm...
                  Creating qt_zh_TW.qm...
                  
                  1 Reply Last reply
                  0
                  • Christian EhrlicherC Offline
                    Christian EhrlicherC Offline
                    Christian Ehrlicher
                    Lifetime Qt Champion
                    wrote on last edited by
                    #21

                    @Tamfub said in Cannot mix incompatible Qt library:

                    Updating qsqlmysql.dll.

                    As you can see the plugin is copied, you have to make sure that the dependencies are also available (search the forum, use Dependency Walker)

                    win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysql
                    else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysqld
                    
                    INCLUDEPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include
                    DEPENDPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include
                    

                    What do you think do gain with this? It's not needed at all.

                    Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                    Visit the Qt Academy at https://academy.qt.io/catalog

                    T 1 Reply Last reply
                    1
                    • Christian EhrlicherC Christian Ehrlicher

                      @Tamfub said in Cannot mix incompatible Qt library:

                      Updating qsqlmysql.dll.

                      As you can see the plugin is copied, you have to make sure that the dependencies are also available (search the forum, use Dependency Walker)

                      win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysql
                      else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysqld
                      
                      INCLUDEPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include
                      DEPENDPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include
                      

                      What do you think do gain with this? It's not needed at all.

                      T Offline
                      T Offline
                      Tamfub
                      wrote on last edited by Tamfub
                      #22

                      @Christian-Ehrlicher said in Cannot mix incompatible Qt library:

                      win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysql
                      else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/lib/ -llibmysqld

                      INCLUDEPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include
                      DEPENDPATH += $$PWD/../../../../../5.15.1/mingw81_64/plugins/sqldrivers/mysql-connector-c-6.1.11-winx64/include

                      What do you think do gain with this? It's not needed at all.
                      

                      If I don't include this, I get this while running my program in Qt:

                      QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers" ...
                      QFactoryLoader::QFactoryLoader() looking at "C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers/qsqlite.dll"
                      Found metadata in lib C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers/qsqlite.dll, metadata=
                      {
                          "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
                          "MetaData": {
                              "Keys": [
                                  "QSQLITE"
                              ]
                          },
                          "archreq": 0,
                          "className": "QSQLiteDriverPlugin",
                          "debug": false,
                          "version": 331520
                      }
                      
                      
                      Got keys from plugin meta data ("QSQLITE")
                      QFactoryLoader::QFactoryLoader() looking at "C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers/qsqlmysql.dll"
                      Found metadata in lib C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers/qsqlmysql.dll, metadata=
                      {
                          "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
                          "MetaData": {
                              "Keys": [
                                  "QMYSQL3",
                                  "QMYSQL",
                                  "QMARIADB"
                              ]
                          },
                          "archreq": 0,
                          "className": "QMYSQLDriverPlugin",
                          "debug": false,
                          "version": 331520
                      }
                      
                      
                      Got keys from plugin meta data ("QMYSQL3", "QMYSQL", "QMARIADB")
                      QFactoryLoader::QFactoryLoader() looking at "C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers/qsqlodbc.dll"
                      Found metadata in lib C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers/qsqlodbc.dll, metadata=
                      {
                          "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
                          "MetaData": {
                              "Keys": [
                                  "QODBC3",
                                  "QODBC"
                              ]
                          },
                          "archreq": 0,
                          "className": "QODBCDriverPlugin",
                          "debug": false,
                          "version": 331520
                      }
                      
                      
                      Got keys from plugin meta data ("QODBC3", "QODBC")
                      QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/Projects/tutorial/progettoMalnati/sharedtexteditor/build-progettoMalnati_srv_2-Desktop_Qt_5_15_1_MinGW_64_bit-Release/release/sqldrivers" ...
                      Cannot load library C:\Qt\5.15.1\mingw81_64\plugins\sqldrivers\qsqlmysql.dll: Impossibile trovare il modulo specificato.
                      QLibraryPrivate::loadPlugin failed on "C:/Qt/5.15.1/mingw81_64/plugins/sqldrivers/qsqlmysql.dll" : "Cannot load library C:\\Qt\\5.15.1\\mingw81_64\\plugins\\sqldrivers\\qsqlmysql.dll: Impossibile trovare il modulo specificato."
                      QSqlDatabase: QMYSQL driver not loaded
                      QSqlDatabase: available drivers: QSQLITE QMARIADB QMYSQL QMYSQL3 QODBC QODBC3
                      Errore nel collegamento al DB
                      "Driver not loaded Driver not loaded"
                      

                      i.e. it cannot load the MYSQL driver. Also, Dependency Walker is taking ages to analyze my .exe. They say it is a normal behaviour, but 5 minutes is too much I guess.

                      1 Reply Last reply
                      0
                      • Christian EhrlicherC Offline
                        Christian EhrlicherC Offline
                        Christian Ehrlicher
                        Lifetime Qt Champion
                        wrote on last edited by
                        #23

                        @Tamfub said in Cannot mix incompatible Qt library:

                        If I don't include this, I get this while running my program in Qt:

                        You're aware that some compiler options and loading a plugin has nothing to do with each other? It's not needed. The only thing you need is (as I already told you) that the program finds the dependencies for your plugin, for instance the mysql dll (search the forum)

                        Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                        Visit the Qt Academy at https://academy.qt.io/catalog

                        T Christian EhrlicherC 2 Replies Last reply
                        1
                        • Christian EhrlicherC Christian Ehrlicher

                          @Tamfub said in Cannot mix incompatible Qt library:

                          If I don't include this, I get this while running my program in Qt:

                          You're aware that some compiler options and loading a plugin has nothing to do with each other? It's not needed. The only thing you need is (as I already told you) that the program finds the dependencies for your plugin, for instance the mysql dll (search the forum)

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                          Tamfub
                          wrote on last edited by Tamfub
                          #24

                          @Christian-Ehrlicher
                          After a long time I managed to analyze the .exe on Dependency Walker, and I got this in the log window:

                          LoadLibraryW("C:\qt\projects\tutorial\progettomalnati\sharedtexteditor\build-progettomalnati_srv_2-desktop_qt_5_15_1_mingw_64_bit-release\release\sqldrivers\qsqlmysql.dll") called from "QT5CORE.DLL" at address 0x0000000068A61823.
                          Loaded "QSQLMYSQL.DLL" at address 0x000000006C5C0000.  Successfully hooked module.
                          Unloaded "QSQLMYSQL.DLL" at address 0x000000006C5C0000.
                          LoadLibraryW("C:\qt\projects\tutorial\progettomalnati\sharedtexteditor\build-progettomalnati_srv_2-desktop_qt_5_15_1_mingw_64_bit-release\release\sqldrivers\qsqlmysql.dll") returned NULL. Error: Impossibile trovare il modulo specificato (126).
                          QSqlDatabase: QMYSQL driver not loaded
                          QSqlDatabase: available drivers: QSQLITE QMARIADB QMYSQL QMYSQL3 QODBC QODBC3
                          Errore nel collegamento al DB
                          "Driver not loaded Driver not loaded"
                          

                          409b70c3-803c-4131-bfb0-db948bbcae23-image.png

                          But this file is in the folder!
                          236acba2-27f2-4132-8377-3bd18231ccc1-image.png

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                          • Christian EhrlicherC Offline
                            Christian EhrlicherC Offline
                            Christian Ehrlicher
                            Lifetime Qt Champion
                            wrote on last edited by
                            #25

                            @Tamfub said in Cannot mix incompatible Qt library:

                            But this file is in the folder!

                            I know, but you don't read what I tell you (already two times) - the plugins has some dependencies to other libraries which must be available... !

                            Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                            Visit the Qt Academy at https://academy.qt.io/catalog

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                            • Christian EhrlicherC Christian Ehrlicher

                              @Tamfub said in Cannot mix incompatible Qt library:

                              But this file is in the folder!

                              I know, but you don't read what I tell you (already two times) - the plugins has some dependencies to other libraries which must be available... !

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                              Tamfub
                              wrote on last edited by
                              #26

                              @Christian-Ehrlicher I actually read what you wrote. But I don't get which libraries must be available, then. Maybe I'm missing a LIBS directive in the .pro file?

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                              • Christian EhrlicherC Christian Ehrlicher

                                @Tamfub said in Cannot mix incompatible Qt library:

                                If I don't include this, I get this while running my program in Qt:

                                You're aware that some compiler options and loading a plugin has nothing to do with each other? It's not needed. The only thing you need is (as I already told you) that the program finds the dependencies for your plugin, for instance the mysql dll (search the forum)

                                Christian EhrlicherC Offline
                                Christian EhrlicherC Offline
                                Christian Ehrlicher
                                Lifetime Qt Champion
                                wrote on last edited by
                                #27

                                @Christian-Ehrlicher said in Cannot mix incompatible Qt library:

                                . The only thing you need is (as I already told you) that the program finds the dependencies for your plugin, for instance the mysql dll (search the forum)

                                ...

                                Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                                Visit the Qt Academy at https://academy.qt.io/catalog

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                                • Christian EhrlicherC Christian Ehrlicher

                                  @Christian-Ehrlicher said in Cannot mix incompatible Qt library:

                                  . The only thing you need is (as I already told you) that the program finds the dependencies for your plugin, for instance the mysql dll (search the forum)

                                  ...

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                                  Tamfub
                                  wrote on last edited by
                                  #28

                                  Hi.

                                  @JKSH said in Cannot mix incompatible Qt library:

                                  I just noticed something else: It looks like you are using 64-bit Qt and 64-bit MinGW. Therefore, you must also use the 64-bit MySQL C connector. (Your screenshots show that you've installed 32-bit MySQL)

                                  I missed this passage. At the moment, I have two choices:

                                  Install 32-bit MySQL - I visited this page but there's no 64-bit version.
                                  8b7915f3-1a2c-408a-a07a-89ee09db7da9-image.png

                                  Use 32-bit Qt and 32-bit MinGW (both are already installed on my PC) - Qt version can be changed from the "Manage kits" tool, but how do I change the qmake version?
                                  575e16c1-477b-4921-8435-9755588f3998-image.png

                                  JKSHJ 1 Reply Last reply
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                                  • T Tamfub

                                    Hi.

                                    @JKSH said in Cannot mix incompatible Qt library:

                                    I just noticed something else: It looks like you are using 64-bit Qt and 64-bit MinGW. Therefore, you must also use the 64-bit MySQL C connector. (Your screenshots show that you've installed 32-bit MySQL)

                                    I missed this passage. At the moment, I have two choices:

                                    Install 32-bit MySQL - I visited this page but there's no 64-bit version.
                                    8b7915f3-1a2c-408a-a07a-89ee09db7da9-image.png

                                    Use 32-bit Qt and 32-bit MinGW (both are already installed on my PC) - Qt version can be changed from the "Manage kits" tool, but how do I change the qmake version?
                                    575e16c1-477b-4921-8435-9755588f3998-image.png

                                    JKSHJ Offline
                                    JKSHJ Offline
                                    JKSH
                                    Moderators
                                    wrote on last edited by
                                    #29

                                    @Tamfub said in Cannot mix incompatible Qt library:

                                    @JKSH said in Cannot mix incompatible Qt library:

                                    I just noticed something else: It looks like you are using 64-bit Qt and 64-bit MinGW. Therefore, you must also use the 64-bit MySQL C connector. (Your screenshots show that you've installed 32-bit MySQL)

                                    I missed this passage.

                                    That's OK. mysql-connector-c-6.1.11-winx64 is 64-bit.

                                    After a long time I managed to analyze the .exe on Dependency Walker

                                    Ask Dependency Walker to open qsqlmysql.dll instead of your .exe.

                                    Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

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                                    • JKSHJ JKSH

                                      @Tamfub said in Cannot mix incompatible Qt library:

                                      @JKSH said in Cannot mix incompatible Qt library:

                                      I just noticed something else: It looks like you are using 64-bit Qt and 64-bit MinGW. Therefore, you must also use the 64-bit MySQL C connector. (Your screenshots show that you've installed 32-bit MySQL)

                                      I missed this passage.

                                      That's OK. mysql-connector-c-6.1.11-winx64 is 64-bit.

                                      After a long time I managed to analyze the .exe on Dependency Walker

                                      Ask Dependency Walker to open qsqlmysql.dll instead of your .exe.

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                                      Tamfub
                                      wrote on last edited by
                                      #30

                                      Ask Dependency Walker to open qsqlmysql.dll instead of your .exe.

                                      It seems there are a bunch problems...
                                      6f203713-711b-4f64-9e8a-5f9f1e9f8286-image.png

                                      What now?

                                      JKSHJ 1 Reply Last reply
                                      0
                                      • T Tamfub

                                        Ask Dependency Walker to open qsqlmysql.dll instead of your .exe.

                                        It seems there are a bunch problems...
                                        6f203713-711b-4f64-9e8a-5f9f1e9f8286-image.png

                                        What now?

                                        JKSHJ Offline
                                        JKSHJ Offline
                                        JKSH
                                        Moderators
                                        wrote on last edited by
                                        #31

                                        @Tamfub said in Cannot mix incompatible Qt library:

                                        It seems there are a bunch problems...

                                        Ignore API-MS-WIN-*.dll and EXT-MS-WIN-.dll. Those are not real problems.

                                        However, libmysql.dll is a real problem. If it is missing, your program cannot load qsqlmysql.dll.

                                        This is what @Christian-Ehrlicher meant by "dependency": qsqlmysql.dll depends on libmysql.dll. You must deploy all of your dependencies.

                                        Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

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                                        • JKSHJ JKSH

                                          @Tamfub said in Cannot mix incompatible Qt library:

                                          It seems there are a bunch problems...

                                          Ignore API-MS-WIN-*.dll and EXT-MS-WIN-.dll. Those are not real problems.

                                          However, libmysql.dll is a real problem. If it is missing, your program cannot load qsqlmysql.dll.

                                          This is what @Christian-Ehrlicher meant by "dependency": qsqlmysql.dll depends on libmysql.dll. You must deploy all of your dependencies.

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                                          Tamfub
                                          wrote on last edited by
                                          #32

                                          I finally managed to make it work now: I just copied libmysql.dll from C:\Program Files\MySQL\MySQL Connector C 6.1\lib into the release folder (the same of the .exe) :)

                                          Thank you all so much for your kind patience!

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