qt with glut on windows 10

[d_stranz]

Your GLWidget class shows two constructors in its header:

GLWidget();
 
// and
 
explicit GLWidget( QWidget * parent = 0 );

GLWidget();

// and

explicit GLWidget( QWidget * parent = 0 );

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These two are indistinguishable to the compiler when used as you are doing ("GLWidget w;"). Get rid of the first constructor (GLWidget()) and the warning will go away.