Some smart souls from XDA Developers have managed to gain root on the Google Pixel and Pixel XL running the Android O Developer preview 1. The method is a little complicated, but it works and gives users root on Android O.
If you’ve been using the Android O DP1 on your Pixel or Pixel XL, and have been waiting to root it, you can now. According to the XDA member, the root was achieved by installing Android 7.1.2 on one partition, and Android O on another partition.
After doing that, SuperSU was installed, and that enabled root on Android O as well. How exactly this works is not known, but it does and that’s what matters. The user has provided a step by step guide on how to get this done.
The method involved in getting root on Android O on the Pixel smartphones isn’t for the faint of heart. Therefore, proceed with caution, and best of luck. Hit the source link for instructions.