Suddenly getting 'undefined ref to 'WinMain@16'

[Doug Broadwell]

After doing a:

qmake -project "CONFIG += debug", "win32: CONFIG += console"
qmake n2.pro

(which I've done many times in the past, I'm getting:

make -f Makefile.Debug
make[1]: Entering directory `C:/Data/Qt/mverse/n2'
g++ -mthreads -Wl,-enable-stdcall-fixup -Wl,-enable-auto-import -Wl,-enable-runtime-pseudo-reloc -Wl,-subsystem,console -o "debug\n2.exe" debug\q
extserialbase.o debug\qextserialport.o debug\win_qextserialport.o -L"c:\Data\Qt\4.2.3\lib" -lQtGuid4 -lQtCored4
C:/Data/Qt/MinGW/bin/../lib/gcc/mingw32/3.4.2/../../../libmingw32.a(main.o)(.text+0x106):main.c: undefined reference to `WinMain@16'
collect2: ld returned 1 exit status
make[1]: *** [debug\n2.exe] Error 1

I'm not sure how to go about debugging this.

Thanks, Doug

[pgorszkowski]

Can you show us your main.c file?

[JPNaude]

Hi,

I've been getting similar types of errors, don't have a message now, but in my case the problems are also in mingw libraries or in qt libraries. I've only experienced this with Qt Creater 0.9 Alpha, so I assumed there's something wrong with the libraries shipped with it.

I haven't tried to solve it yet though,
Cheers
Jaco

[jpn]

Adding or removing "CONFIG += console" requires rebuilding the application (or at least the source file containing main() function). Unfortunately rebuilding doesn't happen automatically because the source file doesn't change.

[Doug Broadwell]

Here's the code for my main.cpp:



#include <QApplication>
#include <QtGui>
#include "MainWindow.h"
#include "comm.h"
#include "state.h"
#include "error.h"
#include "main.h"

#include "ctl_cfg_assoc.h"



//- GLOBAL OBJECT POINTERS -//

MainWindow* mw;
QScrollArea* sa;


QByteArray qbaEmpty;




//----------------------------------------------------------------------------------
// REIMPLEMENTATION OF QApplication::notify() TO CATCH OTHERWISE UNCAUGHT ERRORS |
//---------------------------------------------------------------------------------------------------------
// *FIXME* We want to remove this for production.

qMyApp::qMyApp( int argc, char* argv[] ) : QApplication( argc, argv ) {};

qMyApp::~qMyApp() {};

//---------------------------------------------------------------------------------------------------------

bool qMyApp::notify( QObject* qoReceiver, QEvent* qeEvent ) {

try {

return QApplication::notify( qoReceiver, qeEvent );

} catch( Fatal_Error& E ) {

qDebug() << "\n" << E.Error_String() << "\n";
throw;

} catch( Base_Error& E ) {

qDebug() << "\n" << E.Error_String() << "\n";
throw;

} catch( ... ) {

qDebug("\nUnknown Error Caught\n");
throw;
}
};
//---------------------------------------------------------------------------------------------------------







//---------
// MAIN |
//---------------------------------------------------------------------------------------------------------

int main(int argc, char *argv[]) {


//-- CREATE APPLICATION OBJECT --//

qMyApp app(argc, argv);

//-- CREATE STATE OBJECT --//

Init_State(); // Must come before creating the Serial Port.

//-- CREATE SERIAL PORT OBJECT --//

Init_SerialPort( 2 ); // Create COM2.

//-- CREATE CtlCfgAssoc OBJECT --//

Init_CtlCfgAssoc();

//-- CREATE MAIN WINDOW OBJECT WITH SCROLLBARS --//

mw = new MainWindow;
sa = new QScrollArea;
sa->setWidget( mw );
sa->show();

//-- RUN --//

return app.exec();
}
//---------------------------------------------------------------------------------------------------------


But I haven't changed anything in it from before when it was working. It seems to be an issue with 'main.c' in libmingw32.a but I don't know what it's doing.

Doug

[jpn]

As I told you, rebuild the application:

make clean
qmake
make

[Doug Broadwell]

Sorry if I wasn't clear; I have rebuilt the application and still get this error.

Doug

[Doug Broadwell]

Found the problem (but not what is causing it). For some reason the 'qmake -project' is making a project file with only a subset of the header and source files in it, when I add all the files (I assume that missing the file with main() in it was causing the error) and running qmake it seems to be fine again.

Doug

[jpn]

Well, "qmake -project" is supposed to be something that you run once in the beginning of a project to generate an initial project file. It's not intended to be used to maintain the project file.