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Error Undefined reference when using shared lib
Hello everyone
I am having a problem converting a working project to separate shared libaries and application. I have created a shared libarary and added the code to make it a library:
In the library global:
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#include <QtCore/qglobal.h>
#if defined(OPENMODEM_LIBRARY)
# define OPENMODEMSHARED_EXPORT Q_DECL_EXPORT
#else
# define OPENMODEMSHARED_EXPORT Q_DECL_IMPORT
#endif
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In the library public interface:
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#include "openModem_global.h"
////// EXPORTED CLASS DEFINITION //////
class OPENMODEMSHARED_EXPORT openModem : public QObject
{
Q_OBJECT
public:
openModem(QObject *parent=0);
~openModem();
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When I try to use this library in the app I get this:
Error Undefined reference to _imp_ZN9openModemC1EP7QObject
What am I overlooking?
AD5XJ
need .pro files of both app and library to tell something
it seems that the lib is not loaded. Have you tried a static library or myabe a stub test function?
Error Undefined reference when using shared lib
Here is the .pro code from both lib and app
Library .pro:
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TEMPLATE = lib
DEFINES += OPENMODEM_LIBRARY
QT -= gui
CONFIG = qt thread warn_on debug
win32:CONFIG += dll windows
unix:CONFIG += shared x11
TARGET = openModem
MOC_DIR = moc
OBJECTS_DIR = obj
SOURCES += . . .
win32:SOURCES += . . .
HEADERS += . . .
win32:HEADERS += . . .
win32:LIBS += -lwinmm
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Application .pro
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TEMPLATE = app
TARGET = MultiQ
QT +=
DEPENDPATH = .
INCLUDEPATH = .
CONFIG = qt exceptions thread warn_on debug
win32:CONFIG += windows
unix:CONFIG += unix x11
MOC_DIR = moc
OBJECTS_DIR = obj
DESTDIR = debug
SOURCES += . . .
HEADERS += . . .
win32:LIBS += -L../openModem/openModem.dll
unix:LIBS += -llibopenModem.a
RESOURCES += application.qrc
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Hope this helps
The application is a working application and all modules are the same as in the working app. The only difference is the one noted. I am missing something where the exported symbols are concerned. The linker finds my DLL but the symbols are not resolved.
AD5XJ
RE: Error Undefined reference when using shared lib
try
Library .pro:
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TEMPLATE = lib
TARGET = openmodem
DEFINES += OPENMODEM_LIBRARY
QT -= gui
MOC_DIR = moc
OBJECTS_DIR = obj
SOURCES += ...
HEADERS += ...
win32: {
SOURCES += ...
HEADERS += ...
}
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Application .pro
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TEMPLATE = app
TARGET = multiq
DESTDIR = debug
MOC_DIR = moc
OBJECTS_DIR = obj
DEPENDPATH = .
INCLUDEPATH = .
SOURCES += ...
HEADERS += ...
RESOURCES += application.qrc
LIBS += -L../openmodem -lopenmodem
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Error Undefined reference when using shared lib
This yields more errors in every use of the library objects:
error: invalid use of undefined type `struct openModem'
AD5XJ
Error Undefined reference when using shared lib
Problem solved!
There was a small typo error (lower case where upper case was needed) in the app code that references the objects.
Thanks for your help!
AD5XJ
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