Technique::Technique(const Technique& rhs, const osg::CopyOp& copyop) :
_contextMap(rhs._contextMap), _alwaysValid(rhs._alwaysValid),
- _shadowingStateSet(copyop(rhs._shadowingStateSet)),
+ _shadowingStateSet(copyop(rhs._shadowingStateSet.get())),
_validExpression(rhs._validExpression),
_contextIdLocation(rhs._contextIdLocation)
{