The bound method implementation is restricted to binding to void methods as return values are not supported. This complicates usage of bound methods, as non-void methods used a slots or Object::invokeMethod() targets need to be wrapped in a void method. Simplify this by supporting arbitrary return types and ignoring the return value. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>