Uncaught TypeError: React.__spread is not a function

I'm seeing this error in ./dist/Select.js:57  
Uncaught TypeError: React.__spread is not a function  

```
  render: function () {
    return (
      React.createElement(Input, React.__spread({},  this.props, {type: "select"}))
    );
  }
```

I'm using React v15. Any ideas?
