Segmentation Fault on when trying to construct QApplication

Hi,

I am a complete beginner in Qt. I have just installed Qt, and tried to run a simple hello world application:

#include <QApplication>
#include <QPushButton>

int main(int argc, char* argv[])
{
QApplication app(argc, argv);
QPushButton hello("Hello World");
hello.resize(100,30);
hello.show();
return app.exec();

}

I have compiled it by doing the following:

qmake -project
qmake
make

The project compiles fine, but when I try to run it I get a segmentation fault.

If I replace the QApplication above with QCoreApplication, it works.

Can anyone tell me why this error might be occurring?
(As far as I can see, it is linking with -lQtGui fine).

Are you running the application with a user that has access to the X server (i.e. not as root)?

Yes, I am running the program with a standard user.

When I create a QtWidget application using QtCreator, and have exactly the same code. I can build and run it fine.

So it seems that the problem is with qmake when I try to compile it from the terminal.

If I create a project file called hello.pro using QtCreator, and have the file hello.cpp with the above code, if I build it using qmake, make (instead of QtCreator) it gives a segmentation fault.

But if I build it in QtCreator it will work fine.

Does anyone know why this may be occurring? Are there options that need to be specified to qmake or make?

---

Added after 16 minutes:

Hi, I found the solution to the problem.

In my .bashrc I had the PATH variable as:

export PATH=$PATH:/opt/QtSDK/Desktop/Qt/474/gcc/bin:/opt/QtSDK/QtCreator/bin

instead of

export PATH=/opt/QtSDK/Desktop/Qt/474/gcc/bin:/opt/QtSDK/QtCreator/bin:$PATH

so it was using the version of qmake in /usr/bin which was for Qt 4.3.4

instead of the version in

/opt/QtSDK/Desktop/Qt/474/gcc/bin

which was for version Qt 4.7.4.

Once I changed it around, it accessed the right version of qmake, and worked fine.