Fighting linker errors when building Qt app manually

Question

Hi all,
some time I was using Qt and building apps in IDE (Code::Blocks). Now I need to find a way to build manually - an app must be built on a machine without IDE or anything similar. I followed official manual, but project failed at linking. I'm now using test project, it consists of two files, and still fails:
main.cpp:
#include <QApplication>
#include "header.hpp"
int main(int argc, char* argv[])
QApplication app(argc, argv);
TestClass asdf(0);
asdf.show();
return app.exec();
header.hpp:
#include <QWidget>
#include <QtGui>
class TestClass : public QWidget
Q_OBJECT
public:
TestClass(QWidget* parent);
protected:
void paintEvent(QPaintEvent* event);
TestClass::TestClass(QWidget* parent) : QWidget(parent)
setWindowTitle( tr("Testing window") );
resize(200, 200);
void TestClass::paintEvent(QPaintEvent* event)
QPainter ps(this);
ps.drawLine(10, 10, 100, 100);
Then I ran qmake -project; qmake test1.pro; make. The following error occured:
moc_header.o: In function `TestClass::paintEvent(QPaintEvent*)':
moc_header.cpp:(.text+0x80): multiple definition of `TestClass::paintEvent(QPaintEvent*)'
main.o:main.cpp:(.text+0xc0): first defined here
moc_header.o: In function `TestClass::TestClass(QWidget*)':
moc_header.cpp:(.text+0xf0): multiple definition of `TestClass::TestClass(QWidget*)'
main.o:main.cpp:(.text+0x0): first defined here
moc_header.o: In function `TestClass::TestClass(QWidget*)':
moc_header.cpp:(.text+0xf0): multiple definition of `TestClass::TestClass(QWidget*)'
main.o:main.cpp:(.text+0x0): first defined here
collect2: ld returned 1 exit status
make: *** [test1] Error 1
It generated the following test1.pro:
# Automatically generated by qmake (2.01a) Fri Sep 10 16:42:10 2010
TEMPLATE = app
TARGET =
DEPENDPATH += .
INCLUDEPATH += .
# Input
HEADERS += header.hpp
SOURCES += main.cpp
It's quite strange since in Code::Blocks it builds flawlessly. Is it error in code, or configs need to be corrected?

Answer 1

falconindy wrote:Add #include guards to header.hpp
Include guards made nothing. Still the same error.
stqn wrote:
I don't know why it builds in Code::Blocks, but I would do as the error message suggests and move the functions definitions from the header to a cpp file.
Or move them into the class declaration.
It solved the problem, but I simply can't understand, why definitions in header are causing an error. Basically it is correct, since in C99 aren't any rule rejecting it, only a recommendation. E.g., Boost is made the same way - definitions are put in headers.