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How to run a C++ code in Qt?

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  • SGaistS SGaist

    You have two main functions that are being compiled. Aren't you trying to include too much files in your new project ?

    RelaR Offline
    RelaR Offline
    Rela
    wrote on last edited by Rela
    #18

    @SGaist
    I have these header and cpp files in my C++ code. C++ code
    and add these files to the PS4 Qt project using “Add existing Files”: PS4 Qt

    I also copy the text model (M7) file in the Qt directory and the code reads the data file. I gives the path of the model file using "Argument" in “Desktop Qt5.5 MinGW" run. Previously, I had Qt5.4 and MSVC 2010 and the results including some numbers appeared in "Application Output". Now, using Qt5.5 and MSVC 2013, the “Desktop Qt5.5 MinGW" works without error, but the "Application Output" shows this result, which are zero, instead of some non-zero numbers (cpu and z). Application output

    However, when I compile with "Desktop Qt MSVC2013 64bit", it gives these errors: Issues
    Compile output
    Even if it gives the results using “Desktop Qt5.5 MinGW", it is ok, but it does not.

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    • SGaistS Offline
      SGaistS Offline
      SGaist
      Lifetime Qt Champion
      wrote on last edited by
      #19

      Again, you have multiple main function, that's the first problem to solve. Why do you have more than one ?

      Interested in AI ? www.idiap.ch
      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

      RelaR 1 Reply Last reply
      0
      • SGaistS SGaist

        Again, you have multiple main function, that's the first problem to solve. Why do you have more than one ?

        RelaR Offline
        RelaR Offline
        Rela
        wrote on last edited by
        #20

        @SGaist
        You mean the "main.cpp" and "mainwindow.cpp" ?
        If so, this is the same I did before with Qt5.4.1. There were the same main functions and gave the results in "Application Output".
        I create a new project in Qt creator:
        “New Project” >> “Qt Widgets Application” >> (Class name) “MainWindow” & (Base class) "QMainWindow" >> "Next" and "Finish" this application window:New Project
        After that I added .cpp and .h files of the C++ code using “Add existing Files”.

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        • jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #21

          SGaist means the C/C++ main function:

          int main(int argc, char** argv)
          {
          ...
          }
          

          An application can only have one main function, as the compiler error says you have two of them.

          https://forum.qt.io/topic/113070/qt-code-of-conduct

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          • RelaR Offline
            RelaR Offline
            Rela
            wrote on last edited by Rela
            #22

            I have one "int main(int argc, char argv[])
            { ..."* function in "O_PS .cpp" file, and one main function in "main.cpp" file. Qt

            jsulmJ 1 Reply Last reply
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            • RelaR Rela

              I have one "int main(int argc, char argv[])
              { ..."* function in "O_PS .cpp" file, and one main function in "main.cpp" file. Qt

              jsulmJ Offline
              jsulmJ Offline
              jsulm
              Lifetime Qt Champion
              wrote on last edited by
              #23

              @Rela You should remove one of them.

              https://forum.qt.io/topic/113070/qt-code-of-conduct

              RelaR 1 Reply Last reply
              0
              • jsulmJ jsulm

                @Rela You should remove one of them.

                RelaR Offline
                RelaR Offline
                Rela
                wrote on last edited by Rela
                #24

                @jsulm
                Could you explain how? The main function of "O_PS .cpp" is my C++ code, do I delete:
                int main(int argc, char *argv[])
                {
                QApplication a(argc, argv);
                MainWindow w;
                w.show();

                return a.exec();
                

                } in "main.cpp" ?

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                • jsulmJ Offline
                  jsulmJ Offline
                  jsulm
                  Lifetime Qt Champion
                  wrote on last edited by
                  #25

                  I don't know which of them you have to remove. I don't know your code and I don't know what you want to do. You have to decide which of them is the right one and then just delete the other. You just cannot have more than one entry point (more than one main function) in a C/C++ program.

                  https://forum.qt.io/topic/113070/qt-code-of-conduct

                  RelaR 1 Reply Last reply
                  0
                  • jsulmJ jsulm

                    I don't know which of them you have to remove. I don't know your code and I don't know what you want to do. You have to decide which of them is the right one and then just delete the other. You just cannot have more than one entry point (more than one main function) in a C/C++ program.

                    RelaR Offline
                    RelaR Offline
                    Rela
                    wrote on last edited by
                    #26

                    @jsulm
                    I definitely need my C++ code, because everything to get the results is in the code, but when I create a new project in Qt, the "main.cpp" file is also created. If I right click on it and "Remove File" do I need add this code somewhere?

                    I had Qt5.4.1 before, and it gave results in "Application output" previously using “Desktop Qt5.4 MinGW” with the same main functions.

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                    • SGaistS Offline
                      SGaistS Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on last edited by
                      #27

                      If you already have a main function that does everything then no. Just keep this in mind: having your main function in a file not named main.cpp is pretty unusual for an application, not forbidden, just unusual. Beware of maintenance nightmare.

                      Interested in AI ? www.idiap.ch
                      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                      RelaR 1 Reply Last reply
                      0
                      • SGaistS SGaist

                        If you already have a main function that does everything then no. Just keep this in mind: having your main function in a file not named main.cpp is pretty unusual for an application, not forbidden, just unusual. Beware of maintenance nightmare.

                        RelaR Offline
                        RelaR Offline
                        Rela
                        wrote on last edited by Rela
                        #28

                        @SGaist

                        I created another project file, and added the C++ files, but instead of adding the code .cpp file I copied it in "main.cpp" file. The only change I made was that copied the

                        QApplication a(argc, argv);
                            MainWindow w;
                            w.show();
                        

                        After
                        int main(int argc, char *argv[])
                        {
                        . So, now there is only one main function in "main.cpp".

                        After that I added the text file by "Argument", using MinGW 32bit, gives this "Runtime Library" error: MinGW 32bit I read maybe its because MinGW is 32bit and I need to use 64 bit as compiler.
                        And used "Desktop Qt5.5.1 MSVC 2013 64 bit" , it gives this error: MSVC 64bit

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                        • SGaistS Offline
                          SGaistS Offline
                          SGaist
                          Lifetime Qt Champion
                          wrote on last edited by
                          #29

                          Run it through the debugger, you're doing something fishy in your code. Throwing a bad alloc means that you are trying to allocated more memory than it's available. It might pass on 64bit (not the same memory limits) but if it does, it means that you are doing something else that is wrong and makes your application crash.

                          Interested in AI ? www.idiap.ch
                          Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                          RelaR 2 Replies Last reply
                          0
                          • SGaistS SGaist

                            Run it through the debugger, you're doing something fishy in your code. Throwing a bad alloc means that you are trying to allocated more memory than it's available. It might pass on 64bit (not the same memory limits) but if it does, it means that you are doing something else that is wrong and makes your application crash.

                            RelaR Offline
                            RelaR Offline
                            Rela
                            wrote on last edited by
                            #30
                            This post is deleted!
                            1 Reply Last reply
                            0
                            • SGaistS SGaist

                              Run it through the debugger, you're doing something fishy in your code. Throwing a bad alloc means that you are trying to allocated more memory than it's available. It might pass on 64bit (not the same memory limits) but if it does, it means that you are doing something else that is wrong and makes your application crash.

                              RelaR Offline
                              RelaR Offline
                              Rela
                              wrote on last edited by
                              #31

                              @SGaist
                              When I click on MSVC to debug MSVC and "F5", it gives this error: No engine
                              When I use MinGW and "F5", it gives this error: MinGW

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                              • SGaistS Offline
                                SGaistS Offline
                                SGaist
                                Lifetime Qt Champion
                                wrote on last edited by
                                #32

                                You need to install the debugger for MSVC

                                Interested in AI ? www.idiap.ch
                                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                RelaR 1 Reply Last reply
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                                • SGaistS SGaist

                                  You need to install the debugger for MSVC

                                  RelaR Offline
                                  RelaR Offline
                                  Rela
                                  wrote on last edited by
                                  #33

                                  @SGaist
                                  In "Maintenance Tool.exe" these components were chosen. components Do I need to mark "Windows Runtime" also?
                                  In "Build & Run", there is one debugger, if it should be added manually, from which folder I have to select it? Debugger

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                                  • SGaistS Offline
                                    SGaistS Offline
                                    SGaist
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #34

                                    MSVC debugger can only be obtained from Microsoft website, here

                                    Interested in AI ? www.idiap.ch
                                    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                    RelaR 2 Replies Last reply
                                    0
                                    • SGaistS SGaist

                                      MSVC debugger can only be obtained from Microsoft website, here

                                      RelaR Offline
                                      RelaR Offline
                                      Rela
                                      wrote on last edited by
                                      #35

                                      @SGaist
                                      Thanks, should I install SDK or WDK?
                                      I did search,but it is said that CDB goes with Visual C++, but there is not download link for CDB.

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                                      • SGaistS SGaist

                                        MSVC debugger can only be obtained from Microsoft website, here

                                        RelaR Offline
                                        RelaR Offline
                                        Rela
                                        wrote on last edited by
                                        #36

                                        @SGaist
                                        I installed Windows SDK and chose all components including "debugging tools for windows". Now, in Tools -> Options -> Build & Run -> Debuggers, I see the two paths for CDB. In "Kit" I chose "Desktop Qt5.5.1 MSVC2013 64bit" and from "Debugger" combo, the CDB.
                                        I debug the program with it, and it doesn't give the previous error, but first open the mainwindow.ui and then shows "Debugging starts" in "Application Output" and Compile Output.
                                        As I wrote before, instead of adding the (C++code.cpp) file I copied the code in "main.cpp" file to have one main fucntion. The only change I made was that copied the

                                        QApplication a(argc, argv);
                                            MainWindow w;
                                            w.show();
                                        

                                        After
                                        int main(int argc, char *argv[])
                                        {
                                        in my C++ code. How can I see the results (which are some numbers) in mainwindow.ui?

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                                        • SGaistS Offline
                                          SGaistS Offline
                                          SGaist
                                          Lifetime Qt Champion
                                          wrote on last edited by
                                          #37

                                          Did you implement anything in MainWindow ?

                                          Interested in AI ? www.idiap.ch
                                          Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                          RelaR 1 Reply Last reply
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