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Link external library - undefined reference to function



  • Hello,

    I would like to add an external library called pHash. I added this to .pro file :

    win32:CONFIG(release, debug|release): LIBS += -L$$PWD/Libs/pHash-0.9.4/release -lpHash
    else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/Libs/pHash-0.9.4/debug -lpHash
    
    INCLUDEPATH += $$PWD/Libs/pHash-0.9.4
    DEPENDPATH += $$PWD/Libs/pHash-0.9.4
    
    win32:CONFIG(release, debug|release): PRE_TARGETDEPS += $$PWD/Libs/pHash-0.9.4/release/pHash.lib
    else:win32:CONFIG(debug, debug|release): PRE_TARGETDEPS += $$PWD/Libs/pHash-0.9.4/debug/pHash.lib
    

    But no one function of the library is working. When I try to use one, I have build error "undefined reference to pHashFunction". There is an example of use :

    #include "myclass.h"
    
    #define HAVE_IMAGE_HASH 1 // config
    #include "pHash.h"
    
    void MyClass::perform() {
    	const char *msg = ph_about();
    	qDebug() << msg;
    }
    

    Then there is the build log :

    C:/Qt/Tools/mingw492_32/bin/mingw32-make -f Makefile.Debug clean
    mingw32-make[1]: Entering directory 'C:/Users/vi/Documents/Programmation/QtWorkspace/build-myProject-Desktop_Qt_5_5_0_MinGW_32bit-Debug'
    rm -f debug/qrc_qml.cpp
    rm -f debug/moc_myclass.cpp
    rm -f debug/main.o debug/myclass.o debug/qrc_qml.o debug/moc_myclass.o
    mingw32-make[1]: Leaving directory 'C:/Users/vi/Documents/Programmation/QtWorkspace/build-myProject-Desktop_Qt_5_5_0_MinGW_32bit-Debug'
    C:/Qt/Tools/mingw492_32/bin/mingw32-make -f Makefile.Release clean
    mingw32-make[1]: Entering directory 'C:/Users/vi/Documents/Programmation/QtWorkspace/build-myProject-Desktop_Qt_5_5_0_MinGW_32bit-Debug'
    rm -f release/qrc_qml.cpp
    rm -f release/moc_myclass.cpp
    rm -f release/main.o release/myclass.o release/qrc_qml.o release/moc_myclass.o
    mingw32-make[1]: Leaving directory 'C:/Users/vi/Documents/Programmation/QtWorkspace/build-myProject-Desktop_Qt_5_5_0_MinGW_32bit-Debug'
    01:31:34: Le processus "C:\Qt\Tools\mingw492_32\bin\mingw32-make.exe" s'est terminé normalement.
    01:31:34: Configuration inchangée, étape qmake sautée.
    01:31:34: Débute : "C:\Qt\Tools\mingw492_32\bin\mingw32-make.exe" 
    C:/Qt/Tools/mingw492_32/bin/mingw32-make -f Makefile.Debug
    mingw32-make[1]: Entering directory 'C:/Users/vi/Documents/Programmation/QtWorkspace/build-myProject-Desktop_Qt_5_5_0_MinGW_32bit-Debug'
    g++ -c -pipe -fno-keep-inline-dllexport -g -frtti -Wall -Wextra -fexceptions -mthreads -DUNICODE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -DQT_QUICK_LIB -DQT_GUI_LIB -DQT_QML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_NEEDS_QMAIN -I../myProject -I. -I../myProject/Libs/pHash-0.9.4 -IC:/Qt/5.5/mingw492_32/include -IC:/Qt/5.5/mingw492_32/include/QtQuick -IC:/Qt/5.5/mingw492_32/include/QtGui -IC:/Qt/5.5/mingw492_32/include/QtANGLE -IC:/Qt/5.5/mingw492_32/include/QtQml -IC:/Qt/5.5/mingw492_32/include/QtNetwork -IC:/Qt/5.5/mingw492_32/include/QtCore -Idebug -IC:/Qt/5.5/mingw492_32/mkspecs/win32-g++  -o debug/main.o ../myProject/main.cpp
    g++ -c -pipe -fno-keep-inline-dllexport -g -frtti -Wall -Wextra -fexceptions -mthreads -DUNICODE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -DQT_QUICK_LIB -DQT_GUI_LIB -DQT_QML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_NEEDS_QMAIN -I../myProject -I. -I../myProject/Libs/pHash-0.9.4 -IC:/Qt/5.5/mingw492_32/include -IC:/Qt/5.5/mingw492_32/include/QtQuick -IC:/Qt/5.5/mingw492_32/include/QtGui -IC:/Qt/5.5/mingw492_32/include/QtANGLE -IC:/Qt/5.5/mingw492_32/include/QtQml -IC:/Qt/5.5/mingw492_32/include/QtNetwork -IC:/Qt/5.5/mingw492_32/include/QtCore -Idebug -IC:/Qt/5.5/mingw492_32/mkspecs/win32-g++  -o debug/myclass.o ../myProject/myclass.cpp
    In file included from ../myProject/myclass.cpp:3:0:
    ../myProject/Libs/pHash-0.9.4/pHash.h:299:21: warning: 'cimg_library::CImg<float>* ph_dct_matrix(int)' declared 'static' but never defined [-Wunused-function]
     static CImg<float>* ph_dct_matrix(const int N);
    					 ^
    'C:\Qt\5.5\mingw492_32\bin\rcc.exe' -name qml ../myProject/qml.qrc -o debug/qrc_qml.cpp
    g++ -c -pipe -fno-keep-inline-dllexport -g -frtti -Wall -Wextra -fexceptions -mthreads -DUNICODE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -DQT_QUICK_LIB -DQT_GUI_LIB -DQT_QML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_NEEDS_QMAIN -I../myProject -I. -I../myProject/Libs/pHash-0.9.4 -IC:/Qt/5.5/mingw492_32/include -IC:/Qt/5.5/mingw492_32/include/QtQuick -IC:/Qt/5.5/mingw492_32/include/QtGui -IC:/Qt/5.5/mingw492_32/include/QtANGLE -IC:/Qt/5.5/mingw492_32/include/QtQml -IC:/Qt/5.5/mingw492_32/include/QtNetwork -IC:/Qt/5.5/mingw492_32/include/QtCore -Idebug -IC:/Qt/5.5/mingw492_32/mkspecs/win32-g++  -o debug/qrc_qml.o debug/qrc_qml.cpp
    'C:\Qt\5.5\mingw492_32\bin\moc.exe' -DUNICODE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -DQT_QUICK_LIB -DQT_GUI_LIB -DQT_QML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_NEEDS_QMAIN -D__GNUC__ -DWIN32 -IC:/Qt/5.5/mingw492_32/mkspecs/win32-g++ -IC:/Users/vi/Documents/Programmation/QtWorkspace/myProject -IC:/Users/vi/Documents/Programmation/QtWorkspace/myProject/Libs/pHash-0.9.4 -IC:/Qt/5.5/mingw492_32/include -IC:/Qt/5.5/mingw492_32/include/QtQuick -IC:/Qt/5.5/mingw492_32/include/QtGui -IC:/Qt/5.5/mingw492_32/include/QtANGLE -IC:/Qt/5.5/mingw492_32/include/QtQml -IC:/Qt/5.5/mingw492_32/include/QtNetwork -IC:/Qt/5.5/mingw492_32/include/QtCore -I. ../myProject/myclass.h -o debug/moc_myclass.cpp
    g++ -c -pipe -fno-keep-inline-dllexport -g -frtti -Wall -Wextra -fexceptions -mthreads -DUNICODE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -DQT_QUICK_LIB -DQT_GUI_LIB -DQT_QML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_NEEDS_QMAIN -I../myProject -I. -I../myProject/Libs/pHash-0.9.4 -IC:/Qt/5.5/mingw492_32/include -IC:/Qt/5.5/mingw492_32/include/QtQuick -IC:/Qt/5.5/mingw492_32/include/QtGui -IC:/Qt/5.5/mingw492_32/include/QtANGLE -IC:/Qt/5.5/mingw492_32/include/QtQml -IC:/Qt/5.5/mingw492_32/include/QtNetwork -IC:/Qt/5.5/mingw492_32/include/QtCore -Idebug -IC:/Qt/5.5/mingw492_32/mkspecs/win32-g++  -o debug/moc_myclass.o debug/moc_myclass.cpp
    g++ -Wl,-subsystem,windows -mthreads -o debug/myProject.exe debug/main.o debug/myclass.o debug/qrc_qml.o debug/moc_myclass.o  -lmingw32 -LC:/Qt/5.5/mingw492_32/lib -lqtmaind -lshell32 -LC:/Users/vi/Documents/Programmation/QtWorkspace/myProject/Libs/pHash-0.9.4/debug -lpHash -lQt5Quickd -lQt5Guid -lQt5Qmld -lQt5Networkd -lQt5Cored 
    debug/myclass.o: In function `ZN6myclass7performEv':
    C:\Users\vi\Documents\Programmation\QtWorkspace\build-myProject-Desktop_Qt_5_5_0_MinGW_32bit-Debug/../myProject/myclass.cpp:11: undefined reference to `ph_about'
    collect2.exe: error: ld returned 1 exit status
    Makefile.Debug:83: recipe for target 'debug/myProject.exe' failed
    mingw32-make[1]: *** [debug/myProject.exe] Error 1
    mingw32-make[1]: Leaving directory 'C:/Users/vi/Documents/Programmation/QtWorkspace/build-myProject-Desktop_Qt_5_5_0_MinGW_32bit-Debug'
    makefile:34: recipe for target 'debug' failed
    mingw32-make: *** [debug] Error 2
    

    Thank you in advance for your help :)


  • Lifetime Qt Champion

    Hi,

    What compiler was used to build pHash ?



  • Finally I used a similar library in server side.
    pHash library wasn't compatible with Qt5