How to build qt 5 project on mac - macos

Question

I try to build a simple Qt 5 program on Mac. But I failed.
The code is very simple:
#include <QtWidgets/QApplication>
int main(int argc, char *argv[])
{
QApplication app (argc, argv);
return app.exec();
}
I used:
clang++ -I ~/Qt5.0.0/5.0.0/clang_64/include -L/Users/crazylion/Qt5.0.0/5.0.0/clang_64/lib test.cpp
Then I got this error:
Undefined symbols for architecture x86_64:
"QApplication::exec()", referenced from:
_main in test-jPGORy.o
"QApplication::QApplication(int&, char**, int)", referenced from:
_main in test-jPGORy.o
"QApplication::~QApplication()", referenced from:
_main in test-jPGORy.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Is there anything i missing?

Answer 1

Firstly, don't compile and link Qt projects by hand; use qmake and project files.
Run qmake -project in your source directory to generate a basic project file.
Edit the project file and add the following line: QT += widgets
Now run qmake to generate a makefile.
Now run make to build your program.
Secondly, you can simply #include <QApplication>

Answer 2

If you want to use clang++ in favor of qmake, you need to specify libraries to link against to, along with the library directory (which you supplied).
clang++ -I ~/Qt5.0.0/5.0.0/clang_64/include -L/Users/crazylion/Qt5.0.0/5.0.0/clang_64/lib -lQtCore -lQtGui test.cpp

Answer 3

I had the same problems and it seems to me that there is some sort of bug in the release it gave me some errors because out of a fresh install (using qt creator) i didn't have some obscure qt library (not the normal qt5 modules but some sort of library in development) so I tend to think that it could be qt's problem
That said I have some questions to better understand:
-are you using a IDE?
-if you are using one which is it?
-are you including all the modules in the *.pro for quake?
-have you used 4.8 version, did you experienced these problems with that?
P.S. if you do not have any particular necessity I suggest you to stick to version 4.8 for some time (as I am doing without problem) since 5.0 is just been released