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c++qtdllqt5qmake

How to link external DLLs properly in Qt creator

Am trying to build the project found @ uconfig , the project requires poppler and the author provided pre-built links headers and DLLS

I have downloaded them and this is structure of the project

enter image description here

dll folder contains all the DLLS and poppler contains header files, the pdf_extract.pro has the following content

QT     += core gui widgets xml

TARGET = pdf_extract
TEMPLATE = lib
DEFINES += DATASHEET_EXTRACTOR_EXPORT_LIB
DESTDIR = "$$PWD/../../bin"

CONFIG(release, debug|release) {
    CONFIG += optimize_full
}

SOURCES += \
    $$PWD/datasheet.cpp \
    $$PWD/datasheetpackage.cpp \
    $$PWD/datasheetpin.cpp \
    $$PWD/datasheetbox.cpp \
    $$PWD/pdfdebugwidget/pdfdebugwidget.cpp \
    $$PWD/pdfdebugwidget/pdfdebugviewer.cpp \
    $$PWD/pdfdebugwidget/pdfdebugscene.cpp \
    $$PWD/pdfdebugwidget/pdfdebugitempage.cpp \
    $$PWD/pdfdebugwidget/pdfdebugitempin.cpp \
    $$PWD/pdfdebugwidget/pdfdebugitemtextbox.cpp \
    $$PWD/model/pdfdatasheet.cpp \
    $$PWD/model/pdfpage.cpp \
    $$PWD/model/pdftextbox.cpp \
    $$PWD/model/pdfpin.cpp \
    $$PWD/model/pdfcomponent.cpp \
    $$PWD/controller/pdfloader.cpp

HEADERS += \
    $$PWD/pdf_extract_common.h \
    $$PWD/datasheet.h \
    $$PWD/datasheetpackage.h \
    $$PWD/datasheetpin.h \
    $$PWD/datasheetbox.h \
    $$PWD/pdfdebugwidget/pdfdebugwidget.h \
    $$PWD/pdfdebugwidget/pdfdebugviewer.h \
    $$PWD/pdfdebugwidget/pdfdebugscene.h \
    $$PWD/pdfdebugwidget/pdfdebugitempage.h \
    $$PWD/pdfdebugwidget/pdfdebugitempin.h \
    $$PWD/pdfdebugwidget/pdfdebugitemtextbox.h \
    $$PWD/model/pdfdatasheet.h \
    $$PWD/model/pdfpage.h \
    $$PWD/model/pdftextbox.h \
    $$PWD/model/pdfpin.h \
    $$PWD/model/pdfcomponent.h \
    $$PWD/controller/pdfloader.h

LIBS += -L"$$PWD/../../bin"
LIBS += -L"$$PWD/dll/jpeg62.dll"
LIBS += -L"$$PWD/dll/libfreetype-6.dll"
LIBS += -L"$$PWD/dll/libopenjp2.dll"
LIBS += -L"$$PWD/dll/libpng12.dll"
LIBS += -L"$$PWD/dll/libpoppler-80.dll"
LIBS += -L"$$PWD/dll/libpoppler-qt5.dll"
LIBS += -L"$$PWD/dll/libtiff3.dll"
LIBS += -L"$$PWD/dll/zlib1.dll"

INCLUDEPATH += $$PWD/../../


LIBS += -lkicad

macx {
    LIBS += -L /usr/local/lib
    INCLUDEPATH += /usr/local/include 
}

yet when I try to build the project I get these errors... am not sure what am doing wrong or missing

enter image description here

Solution

  • According to qmake documentation, using unix standards to specify linked libraries will work on Windows, too. Anyway, instead of

    LIBS += -L"$$PWD/dll/jpeg62.dll"

    I would try

    LIBS += "-L$$PWD/dll" - ljpeg62

    or just use Windows style:

    LIBS += $$PWD/dll/jpeg62.dll