diff --git a/src/gui/opengl/qopenglframebufferobject.cpp b/src/gui/opengl/qopenglframebufferobject.cpp
index cd6468cccdf..3102e1ecd24 100644
--- a/src/gui/opengl/qopenglframebufferobject.cpp
+++ b/src/gui/opengl/qopenglframebufferobject.cpp
@@ -436,6 +436,7 @@ void QOpenGLFramebufferObjectPrivate::init(QOpenGLFramebufferObject *, const QSi
     samples = qBound(0, int(samples), int(maxSamples));
 #endif
 
+    samples = qMax(0, samples);
     requestedSamples = samples;
     size = sz;
     target = texture_target;