Why does qDebug work in Release builds?

c++ qt qdebug
sashoalm picture sashoalm · Nov 21, 2012 · Viewed 15k times · Source

Coming from MFC, I treated qDebug() much like TRACE(), assuming that it is removed from Release builds by the preprocessor (in MFC it's done using #define TRACE 1 ? (void*) 0 : AfxTrace).

To my surprise, however, qDebug() is executed in Release builds as well. How do I change this? And also, why is this so, what was the reasoning of the developers of Qt behind this decision?

Answer

Angew is no longer proud of SO picture Angew is no longer proud of SO · Nov 21, 2012

qDebug is also preprocessor-controlled, but it has its own special macro, QT_NO_DEBUG_OUTPUT. If you add that to your Release build defines, it will be removed.

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