QT5 QGraphicalEffects 1.0 OpacityMask systematic Error at runtime

[billouparis]

Running this QML file:

@
import QtQuick 2.0
import QtGraphicalEffects 1.0
import "."

Item {
id: idRoot
width: 800
height: 480
Image {
id: idBackGround
x: 0
y: 0
width: 800
height: 480
source: "../../resource/_DSC7038.jpg"
visible: false
}
Image {
id: idMaskA
source: "../../resource/MASKA.png"
visible: false
}

OpacityMask {
    anchors.fill: idRoot
    source: idBackGround
    maskSource: idMaskB 
}

}
@

cause these errors:
file:///home/billouparis/Qt5.0.0/5.0.0/gcc_64/qml/QtGraphicalEffects/OpacityMask.qml:116:5: QML SourceProxy: Binding loop detected for property "output"
file:///home/billouparis/Qt5.0.0/5.0.0/gcc_64/qml/QtGraphicalEffects/OpacityMask.qml:111:5: QML SourceProxy: Binding loop detected for property "output"

The result is running fine, but I have doubts on these error lines though.

Do you think I should register a bug for this?

Regards,
Bill