Crash in QSGOpaqueTextureMaterial::setTexture when using Canvas

import QtQuick 2.2
import QtQuick.Controls 1.2

ApplicationWindow {
    id: window
    width: 640
    height: 480
    visible: true

    property real minimumValue: 0
    property real maximumValue: 100
    property real currentValue: 0

    Timer {
        interval: 500
        repeat: false
        running: true
        onTriggered: {
            var v = currentValue + 10
            if (v > maximumValue)
                v = minimumValue
            currentValue = v
        }
    }

    Canvas {
        id: theCanvas
        anchors.fill: parent

        property real radius: 100
        property real pct: (currentValue - minimumValue) / (maximumValue - minimumValue)

        onPctChanged: theCanvas.requestPaint()

        onPaint: {
            var ctx = theCanvas.getContext("2d")
            ctx.clearRect(0, 0, 2 * radius, 2 * radius)
        }
    }
}

0	??			0x70	
1	QSGOpaqueTextureMaterial::setTexture	qsgtexturematerial.cpp	195	0x7fffe7439b4b	
2	QSGSimpleTextureNode::setTexture	qsgsimpletexturenode.cpp	229	0x7fffe7438c15	
3	QQuickCanvasItem::updatePaintNode	qquickcanvasitem.cpp	765	0x7fffe75dfdee	
4	QQuickWindowPrivate::updateDirtyNode	qquickwindow.cpp	2984	0x7fffe74b5a70	
5	QQuickWindowPrivate::updateDirtyNodes	qquickwindow.cpp	2722	0x7fffe74b4731	
6	QQuickWindowPrivate::syncSceneGraph	qquickwindow.cpp	341	0x7fffe74a853a	
7	QSGRenderThread::sync	qsgthreadedrenderloop.cpp	515	0x7fffe74736e4	
8	QSGRenderThread::syncAndRender	qsgthreadedrenderloop.cpp	561	0x7fffe7473bac	
9	QSGRenderThread::run	qsgthreadedrenderloop.cpp	677	0x7fffe7474814	
10	QThreadPrivate::start	qthread_unix.cpp	331	0x7ffff695cc27	
11	start_thread	/usr/lib/debug/lib/x86_64-linux-gnu/libpthread-2.19.so	312	0x7ffff56ae182	
12	clone	/usr/lib/debug/lib/x86_64-linux-gnu/libc-2.19.so	111	0x7ffff60ba47d